Subjects: Psychology >> Cognitive Psychology submitted time 2017-12-29
Abstract： Numerous evidence has indicated that the high-level cognitive functions are not carried out by isolated operation of single brain area, but through the dynamic interactions between multiple large-scale brain networks. Among them, frontoparietal control network plays a pivotal gate-keeping role in goal-directed cognition, modulating the dynamic balance between the dorsal attention network and default network. Dorsal attention network is mainly responsible for the external top-down attention-oriented and visual space perception. The default network is considered to support internally oriented and self-referential mental processes. By selectively cooperating with the default network or dorsal attention network according to the attentional demands of the task, the frontoparietal control network may serve as a cortical mediator linking the two networks to support adaptive cognitive processes. Regarding these three large-scale brain networks, there are still some debates in the nodes (regions), the functional characterization and interactive relationship. Future research needs to further explore the functional roles of the subsystems within each network, and use the effective connectivity method to examine the direction and dynamics of the information transmission within and between networks.
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Subjects: Library Science，Information Science >> Library Science submitted time 2017-12-29 Cooperative journals: 《知识管理论坛》
Abstract：
Subjects: Library Science，Information Science >> Library Science submitted time 2017-12-29 Cooperative journals: 《知识管理论坛》
Abstract：[目的/意义]科技新媒体是科技信息服务和新媒体传播手段结合的产物，在内容、模式和载体的创新等方面都值得各类知识服务平台借鉴学习。[方法/过程] 选取《2016中国科技新媒体排行榜》中影响力排名前10名的科技新媒体，对其内容来源、传播渠道、线上与线下活动开展情况及盈利模式进行梳理和分析，揭示科技新媒体呈现的特点及存在问题。[结果/结论]图书馆移动知识服务平台应借鉴科技新媒体，在保证内容质量的基础上吸引更多的用户参与内容建设，形成传播资讯、线上服务与线下活动三位一体的平台，形成自己的市场竞争力 。
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To prepare a drug-loading film using chitosan and carboxymethyl chitosan as the carrier materials for delivering matrine to oral ulcers. Methods Matrine-loading films using chitosan or carboxymethyl chitosan as the carrier materials were prepared by solution casting method and orthogonal experiment at room temperature. The mechanical properties, surface morphology and drug-loading capacity of the drug-loading film were characterized using tensile test, scanning electron microscopy (SEM), swelling test and in vitro drug release test. Results When the molecular weight of chitosan was 650 000 and the mass ratio of chitosan/glycerol was 1∶1.4, the prepared film had the maximum mechanical strength and tensile modulus reaching 0.7875 MPa. SEM observation showed that matrine aggregated at the bottom of the drug-loading film with an asymmetrical distribution. The in vitro drug release test showed that the film had a high drug-loading capacity and a sustained drug release property. The duration of drug release from the drug-loading film was prolonged as the molecular weight of chitosan increased, reaching 23 h when the molecular weight of chitosan was 650 000. The duration of drug release was further increased to 108 h when the bottom of the drug-loading film was coated with a layer of 1% carboxymethyl chitosan. Conclusion The matrix materials of the drug-loading film are natural, green, nontoxic and biodegradable, and the preparation of the film is simple without using large quantities of organic solvents. The novel drug-loading film can obviously prolong the duration of drugs release for better local drug delivery to oral ulcers in a sustained manner.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To study the actual glomerular filtration rates (GFR) in patients with nonfunctioning kidneys as shown by intravenous pyelography (IVP) using single photon emission computed tomography (SPECT) dynamic renal scintigraphy and dual-plasma sample clearance method. Methods We retrospectively analyzed 107 patients with nonfunctioning kidneys shown by IVP who underwent renal dynamic 99Tcm-DTPA SPECT imaging. GFR was measured by Gates' methods (GFRGates') and dual-plasma sample clearance method (GFRdual-plasma). Based on the dynamic functional images and GFRdual-plasma measurements, the patients were categorized into mild renal impairment (GFRdual-plasma≥30 mL/min), moderate renal impairment group (GFRdual-plasma of 20-30 mL/min), severe renal impairment group (GFRdual-plasma of 10 to 20 mL/min), and nonfunctioning kidney group (GFRdual-plasma≤10 mL/min), and GFRGates' were compared among the groups. Results According to GFRdual-plasma, the numbers of patients having mild, moderate, and severe renal impairment and nonfunctioning kidneys were 12(11.2% ), 33 (30.8%), 41(38.3%), and 21(19.6%), respectively. GFRdual-plasma and GFRGates' were not significantly different in mild and moderate renal impairment groups, but in patients with severe renal impairment, GFRdual-plasma was significantly lower than GFRGates' (13.9± 6.2 vs 18.8±4.2 mL/min; t=-2.73, P=0.03), which was also the case with patients with nonfunctinging kidneys (4.5±2.1 vs 7.2±3.2 ml/min; t=-3.81, P=0.005). Conclusion Of the patients with nonfunctinging kidneys shown by IVP, only 58% of them actually have severe renal impairment or worse, and further SPECT dynamic renal scintigraphy is necessary to assess the actual risk of renal function impairment before operation.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： An esophageal squamous cell carcinoma measuring 18.3 cm in length and 5 cm in diameter was found in the mediastinum of a 53-year man. The patient underwent a modified 3-stage esophagectomy and an esophagogastrostomy at the cervical level (Wu's method). The operation was performed smoothly and the patient recovered uneventfully after the operation. The patient was followed up for 6 months after discharge and reported no difficulties in eating with improved quality of life. This case represents the world's longest esophageal cancer that had been surgically removed. Local advanced esophageal cancer should be removed immediately to prevent potential occurrence of esophageal obstruction, tracheoesophageal fistula or aorto-esophageal fistula.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To evaluate the therapeutic effect of three-dimensional digital orthopedic techniques in treatment of acetabular fractures. Methods We retrospectively analyzed 50 cases of acetabular fracture treated between March, 2007 and December, 2013. The lamellar CT scanning data were imported into Mimics software, and 3D anatomical models of the pelvic and proximal femur were reconstructed. Computer-assisted analysis was carried out to understand the condition of fractures and simulate fracture reduction. The pelvic models were manufactured by rapid prototyping technique for definite diagnosis and typing of acetabular fractures and subsequent surgical treatment. Results Three-dimensional reconstruction images and rapid prototyping pelvic models faithfully represented the findings in operations. Preoperative simulation of the operation shortened the time of operation and reduced the volume of bleeding in the operation. All the patients were followed up for 6 to 24 months. According to Matta imaging score, anatomical reduction was achieved in 41 cases and satisfactory reduction in 9 cases. According to the Harris functional criteria, 32 patients had excellent, 12 had good and 6 had acceptable outcomes with a rate of excellent and good outcomes of 88% . Conclusion Three-dimensional digital orthopedic techniques allow accurate display of the acetabulum and the spatial relation of the anatomic structures to assist in fracture diagnosis, typing and treatment.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To improve Luo-Ye pump-based stress-forming system and optimize the stimulating effect on smooth muscle cells during cultivation of tissue-engineered blood vessels (TEBV). Methods A new Luo-Ye pump-based TEBV 3D culture system was developed by adding an air pump to the output of the bioreactor. A pressure guide wire was used to measure the stress at different points of the silicone tube inside the TEBV bio-reactor, and fitting curves of the stress changes over time was created using Origin 8.0 software. The TEBVs were constructed by seeding vascular smooth muscle cells (VSMCs) isolated from human umbilical artery on polyglycolic acid (PGA) and cultured under dynamic conditions with 40 mmHg resistance (improved group), dynamic conditions without resistance (control group) or static condition (static group) for 4 weeks. The harvested TEBVs were then examined with HE staining, masson staining, α-SMA immunohistochemical staining, and scanning and transmission electron microscopy with semi-quantitative analysis of collagen content and α-SMA expression. Results The measured stress values and the fitting curves showed that the stress stimuli from the Luo-Ye pump were enhanced by adding an air pump to the output of the bioreactor. Histological analysis revealed improved VSMC density, collagen content and α-SMA expression in the TEBVs constructed with the improved method as compared with those in the control and static groups. Conclusion Adding an air pump to the Luo-Ye pump significantly enhances the stress stimulation in the TEBV 3-D culture system to promote the secretion function of VSMCs.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To investigate the relationship between polymorphisms of surfactant protein D (rs3088308 and rs721917) and the susceptibility to silicosis. Methods This case-control study included 125 silicosis patients and 125 individuals exposed to industrial dust but without silicosis (control group), who were strictly matched with the case group for age, gender, work type and cumulative length of dust exposure. The rs3088308 and rs721917 polymorphisms of surfactant protein-D were detected in all the participants using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results The frequencies of T/T, T/A and A/A genotypes of surfactant protein-D rs3088308 locus were 22.2%, 71.2% and 5.6% in the case group, significantly different from the frequencies of 17.6%, 58.4% and 24.0% in the control group, respectively (P< 0.05). The frequencies of C/C, C/T and T/T genotypes of rs721917 locus were 17.6%, 56.8% and 25.6% in the case group, similar to the frequencies of 15.2% , 60.0% and 24.8% in the control group, respectively (P>0.05). Conclusion Surfactant protein-D rs3088308 polymorphism is significantly associated with silicosis, and the T allele may be a risk factor for silicosis in individuals exposed to industrial dust.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To investigate the relationship between polymorphisms of surfactant protein D (rs3088308 and rs721917) and the susceptibility to silicosis. Methods This case-control study included 125 silicosis patients and 125 individuals exposed to industrial dust but without silicosis (control group), who were strictly matched with the case group for age, gender, work type and cumulative length of dust exposure. The rs3088308 and rs721917 polymorphisms of surfactant protein-D were detected in all the participants using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results The frequencies of T/T, T/A and A/A genotypes of surfactant protein-D rs3088308 locus were 22.2%, 71.2% and 5.6% in the case group, significantly different from the frequencies of 17.6%, 58.4% and 24.0% in the control group, respectively (P< 0.05). The frequencies of C/C, C/T and T/T genotypes of rs721917 locus were 17.6%, 56.8% and 25.6% in the case group, similar to the frequencies of 15.2% , 60.0% and 24.8% in the control group, respectively (P>0.05). Conclusion Surfactant protein-D rs3088308 polymorphism is significantly associated with silicosis, and the T allele may be a risk factor for silicosis in individuals exposed to industrial dust.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To investigate the effect of miR-101 on biological behaviors of colorectal cancer cell line SW620. Methods CCK-8 method, colony formation assay, cell cycle analysis and apoptosis analysis were applied to assess the effects of miR-101 on cell proliferation, invasion and apoptosis of SW620 cells. Results Over-expression of miR-101 in SW620 cells significantly suppressed the cell proliferation and attenuated the colony-forming ability of the cells. Flow cytometry showed that over-expression of miR-101 in SW620 cells caused obvious cell cycle arrest in G2/M and G1 phases, and significantly increased the cell apoptosis rate. Conclusion Over-expression of miR-101 can inhibit the proliferation, cause cell cycle arrest and promote apoptosis of colorectal cancer SW620 cells.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To observe the effect of parathyroid hormone (PTH)(1-34) on the expression of matrix Gla protein (MGP) and Wnt/β-catenin signaling pathway and elucidate the possible molecular mechanism of PTH (1-34) in the prevention and treatment of osteoporosis. Methods MG63 cells treated with PTH (1-34) at 10-9, 10-8, and 10-7 mol/L, alone or in combination with Wnt/beta-catenin signaling pathway inhibitors DKK-1 (200 ng/ml) were examined for mRNA and protein expressions related with Wnt/β-catenin signaling with real-time PCR and Western blotting. The cell differentiation after the treatment was assessed with alkaline phosphatase (ALP) staining and cell viability assay. Results PTH (1-34) significantly increased the expression of MGP in a dose-dependent manner in MG63 cells (P<0.05 or P<0.01). PTH treatment obviously enhanced ALP activity in the cells, and this effect was suppressed by DKK-1. Combined treatment with DKK-1 partially blocked PTH-induced enhancement of ALP activity (P<0.05). PTH promoted the expression of MGP and enhanced LRP5, β-catenin, and Runx2 expressions in Wnt/β-catenin signaling pathway at both protein and mRNA levels (P<0.05 or P<0.01). DKK-1 partially blocked the effect of PTH (1-34) on Wnt/β-catenin signaling pathway (P<0.05) without affecting MGP expression. Conclusion PTH (1-34) significantly increases the expressions of MGP and proteins in the Wnt/β-catenin signaling pathway. Wnt/β-catenin signaling pathway and MGP mediate the regulation of osteogenosis by PTH.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To explore a new method for finite element modeling to achieve material property assignment based on in situ CT gray value in simulated osteotomies for deformities. Methods A CT scan dataset of the lower limb of a patient with extorsion deformity was obtained for three-dimensional reconstruction using Mimics software and preparing a solid model. In the CAD software, the parameters for osteotomy simulation were defined including the navigation axis, rotation angle and reference plane. The tibia model was imported to the FEA pre-processing software for meshing procedure and then exported to Mimics. All the segments of the tibia meshed model were assigned uneven material properties based on the relationship between CT gray values and material properties in the Mimics software. Finally, all the segments of the tibia model, reference axis and reference plane were assembled in the pre-processing software to form a full finite element model of a corrected tibia, which was submitted to resolver for biomechanical analysis. Results The tibia model established using our modeling method had inhomogeneous material properties based on CT gray values, and was available for finite element analysis for the simulation of osteotomy. Conclusions The proposed finite element modeling method, which retains the accuracy of the material property assignment based on CT gray value, can solve the reposition problem commonly seen in modeling via the routine method of property assignment and provides an efficient, flexible and accurate computational biomechanical analysis method for orthopedic surgery.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To investigate the expression of microRNA-107 (miR-107) and its functional role in hepatocellular carcinoma (HCC). Methods The gene chip data of HCC obtained from the Gene Expression Omnibus (GEO) database and the Cancer Genome Atlas (TCGA) database were used to analyze the expression levels of miR-107 in liver cancer. Twenty-two pairs of fresh surgical specimens of HCC and adjacent tissues and 53 paraffin-embedded specimens of HCC were examined for miR-107 expression by qRT-PCR. The correlation of the expression levels of miR-107 with the clinicopathologic characteristics of the patients were analyzed. The role of miR-107 in regulating the proliferation of hepatocellular carcinoma cells were determined by MTT assay in Huh7 cells transfected with a miR-107 mimic or inhibitor. Results The expression levels of miR-107 were significantly up-regulated in HCC tissues as compared to the adjacent tissues (P<0.05) in positive correlation with the tumor size (P<0.032). Transfection with miR-107 mimics significantly promoted the cell proliferation (P< 0.0001) while miR-107 inhibitor inhibited the cell proliferation (P<0.0001). Conclusion The expression of miR-107 is upregulated in HCC tissues and its expression levels are correlated with HCC cell proliferation, suggesting its role as a potential oncogene in liver cancer.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Restriction by hardware caused the very low projection number at a single phase for 4-dimensional cone beam (4D-CBCT) CT imaging, and reconstruction using conventional reconstruction algorithms is thus constrained by serious streak artifacts and noises. To address this problem, we propose an approach to reconstructing 4D-CBCT images with multi-phase projections based on the assumption that the image at one phase can be viewed as the motion-compensated image at another phase. Specifically, we formulated a cost function using multi-phase projections to construct the fidelity term and the TV regularization method. For fidelity term construction, the projection data of the current phase and those at other phases were jointly used by reformulating the imaging model. The Gradient-Projection-Barzilai-Line search (GPBL) method was used to optimize the complex cost function. Physical phantom and patient data results showed that the proposed approach could effectively reduce the noise and artifacts, and the introduction of additional temporal correlation did not introduce new artifacts or motion blur.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To explore the race- and gender-specific distribution characteristics of rs1891385A/C and rs10975519C/T polymorphism of interleukin-33 (IL-33) gene in Zhuang and Han populations. Methods The polymorphisms of rs1891385A/C and rs10975519C/T of IL-33 gene in 283 subjects from Guangxi Zhuang Autonomous Region were analyzed with single base extension (PCR-SEB) and DNA sequencing to analyze the differences in their distribution frequencies between genders and between Zhuang and Han populations. Results Three genotypes (AA, AC and CC) were found in rs1891385A/C with frequencies of 64.3% , 32.5% and 3.2% , respectively. The genotype and allele frequencies of rs1891385A/C in this Guangxi population showed no significant difference between Zhuang and Han subpopulations and between genders (P>0.05), but differed significantly from those in European and African black populations (P<0.01). Three genotypes (CC, CT and TT) were identified in rs10975519C/T with frequencies of 34.3% , 53.0% , and 12.7% , respectively, showing no significant ethnic or gender-specific differences in this population (P>0.05). The genotype frequency of rs10975519C/T in this population differed significantly from those in the European and Japanese populations (P<0.01), but the allele frequencies only showed significant differences from those in the European population (P<0.01). Conclusion rs1891385A/C and rs10975519C/T polymorphisms of IL-33 gene show a race-specific difference.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To investigate the function of AT motif binding factor 1 (ATBF1) in colorectal cancer. Methods ATBF1 protein expression was detected in 146 pairs of colorectal cancer tissues and the adjacent tissues using immunohistochemistry. ATBF1 protein expression was also examined in colorectal cell lines with laser confocal microscopy. ATBF1-A protein expression in colorectal cancer tissues of different differentiation grades and in the colorectal cancer cell lines were detected with estern blotting. The expressions of ATBF1 mRNA in 38 moderately differentiated colorectal cancer tissues and the paired adjacent tissues and in the colorectal cancer cell lines were tested using RT-PCR. Results ATBF1 protein expression levels in colorectal cancer tissues and adjacent tissues differed significantly (P<0.001), and its expression increased significantly in positive correlation with the grade of tumor differentiation (P<0.001) but in negative correlation with tumor metastasis. ATBF1 mRNA expression and ATBF1 protein expression were significantly correlated (P=0.100). The ATBF1 protein and mRNA expressions also differed significantly among different colorectal cancer cell lines. Conclusion ATBF1 executes the role of a tumor suppressor gene in colorectal cancer, and its protein expression is associated with tumor differentiation and lymph node metastases.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To investigate the effect of docosahexaenoic acid (DHA) on invasiveness of aflatoxin B1 (AFB1)-induced hepatocellular carcinoma cells in vitro. Methods HepG2.2.15 cells were exposed to different concentrations of AFB1 and DHA plus AFB1. The cell migration and invasion were assessed using wound-healing and Transwell assay, and flow cytometry was used to analyze the cell cycle changes. The ultrastructural changes of the cells were observed by transmission electron microscopy. Results Compared with the control group, the cells exposed to2 μmol/L AFB1 showed obviously enhanced migration and invasion with decreased cell ratio in G0/G1 phase and increased cell ratio in G2/M phase but no changes in S phase cells; transmission electron microscopy revealed the presence of multiple nucleoli and significantly increased mitochondria and Golgi apparatus in the exposed cells. Compared with AFB1-exposed cells, the cells treated with DHA and AFB1 showed decreased migration and invasion abilities, and the G0/G1 phase cells increased and G2/M phase cells decreased significantly; ultrastructurally, the cells contained single nucleoli with decreased mitochondria and vacuolization occurred in the cytoplasm. Conclusion DHA can significantly inhibit AFB1-induced enhancement of cell migration and invasion in hepatocellular carcinoma cells in vitro.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To prepare a novel strontium-containing calcium sulfate and assess its and biocompatibility. Methods A novel strontium-containing α-calcium sulfate hemihydrate (Sr-caS) bone substitute as prepared with hydrothermal reaction and examined for X-ray diffraction (XRD), Fourier transform infrared (FTIR) and thermogravimetric differential scanning calorimetric (TG-DSC) patterns. The biocompatibility of the material was evaluated by in vitro cytotoxicity test in L-929 cells, hemolysis test of blood, and in vivo implantation test in SD rats. Results The XRD spectra of the prepared Sr-CaS powder highlighted 3 strong characteristic peaks of α-CaSO4 at 14.63°, 25.72° and 29.80° with a strontium-specific peak at 24.78°. The FTIR patterns of Sr-CaS resembled those of CaS. TG-DSC results showed that the material contained a non-evaporable water content of 6.03%. In vitro cytotoxicity test in L-929 cells suggested that the material had a class 1 cytotoxicity, and the hemolysis rate of its aqueous extract was 4.3%. The material implanted in the muscular tissues of SD rats maintained a steady state in the surrounding tissues. Conclusion This strontium-containing calcium sulfate material we prepared shows an excellent biocompatibility for potential use as a novel artificial bone material.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-27 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To investigate the impact of heart valve calcification (HVC) on cardiovascular outcomes in patients on maintenance hemodialysis (MHD). Methods We enrolled 302 Chinese patients on MHD between 2009 and 2011 including 99 with HVC identified by echocardiography screening. All the patients were followed up for 2 years and survival analysis was performed with all-cause mortality, cardiovascular mortality and new onset cardiovascular events as the endpoints. Cox regression analysis was used for analyzing the impact of heart valve calcification on the cardiovascular outcomes of the patients. Results The mean age of the total patients was 58.2�5.0 years when receiving the initial MHD, and 53.6% were male patients. The overall mortality, cardiovascular mortality and new on-set cardiovascular events in HVC and non-HVC groups were 30.3% vs 16.3% , 22.2% vs 6.9% , and 48.5% vs 25.6% , respectively (P<0.05). Kaplan-Meier survival analysis showed a significant difference in all-cause mortality (P=0.006), cardiovascular mortality (P<0.001) and new-onset cardiovascular events (P<0.001) between HVC and non-HVC groups. After adjustment, Cox regression analysis identified HVC as a risk factor for increased all-cause mortality (HR=1.88; 95% CI: 1.11-3.19), cardiovascular mortality (HR=3.47, 95% CI: 1.76-6.84) and cardiovascular events (HR=1.64, 95% CI: 1.09-2.47). Conclusions HVC is an independent risk factor for increased cardiovascular mortality and new cardiovascular events in patients on MHD.
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