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991.
Ensuring data quality in a multicenter clinical trial: remote site data entry, central coordination and feedback 总被引:1,自引:0,他引:1
J B Severe N R Schooler J H Lee G Haas K T Mueser P Rosen D Shortell M Shumway 《Psychopharmacology bulletin》1989,25(3):488-490
In an ongoing multicenter clinical trial, "Treatment Strategies in Schizophrenia," the five participating sites have the capacity to perform a variety of tasks or study functions independently. These tasks include (a) verification of diagnostic eligibility through the use of computerized decision algorithms; (b) assignment of patients to treatment based on prognostic indicators using a computerized randomization algorithm; (c) entry of data into a microcomputer using a clinical trial data management system that performs simple range and missing data item checks; and (d) regular transfer of all data to the central coordinating team. The clinical trial data management system employed allows for both independent site functioning and assurance of consistency across sites. The integration of a variety of software outside the main data management system provides the central coordinators with the tools to monitor critical data as it is collected, as well as the capacity to assess the flow, quality, and uniformity of the ongoing trial. 相似文献
992.
Yu Y Harris RI Yang JL Anderson HC Walsh WR 《Journal of biomedical materials research. Part A》2004,70(1):122-128
Differential expression of multiple osteogenic factors may be responsible for the different osteoinductivity of osteosarcoma cell lines. We compared in vivo osteoinductivity of human osteosarcoma cell lines (Saos-2 vs. U-2 OS) in nude mice, and their in vitro expression of various osteogenic factors of protein level by quantitative immunocytochemistry and mRNA level by RT-PCR and/or in situ hybridization. Saos-2 cells, but not U-2 OS, were osteoinductive in vivo. Significantly higher expression (independent t-test, all p < 0.005) of osteogenic factors were observed in Saos-2 cells compared with U-2 OS, which included bone morphogenetic proteins (particularly BMPs-2, 3, 4, and 7), transforming growth factor-beta (TGF-beta), BMP receptor (BMPR)-1A, receptor-regulated Smads (R-Smads), Smads 1, 2, and 5, and common-mediator Smad (Co-Smad), Smad 4. In contrast, U-2 OS cells expressed higher levels of inhibitory Smad 6 (I-Smad) protein than Saos-2 cells (p < 0.001). These results suggest that a combination of osteogenic factors (BMPs, TGF-beta, BMPRs, and R/Co-Smads) against I-Smad may play important roles in the Saos-2 cell osteoinductivity. This may have a clinical implication in selecting key osteogenic factors for combined therapy for bone defect diseases. The characterized cell lines can be used as positive and negative controls for the assessments of both in vitro and in vivo bone formation capabilities of designed tissues or biomaterials. 相似文献
993.
Füst G Arason GJ Kramer J Szalai C Duba J Yang Y Chung EK Zhou B Blanchong CA Lokki ML Bödvarsson S Prohászka Z Karádi I Vatay A Kovács M Romics L Thorgeirsson G Yu CY 《International immunology》2004,16(10):1507-1514
The genetic basis for addiction to tobacco smoking--particularly that of the perception of olfactory stimuli that may be important in reinforcing smoking addiction--is largely unknown. A cluster of genes for olfactory receptors is in close proximity to the MHC region on chromosome 6. Polymorphisms of MHC class III genes (RCCX modules, TNFA promoter polymorphisms) were determined in 101 healthy subjects and 232 coronary artery disease (CAD) patients from Hungary with defined tobacco smoking habits. A highly significant association between ever smoking (past + current smokers) and a specific MHC haplotype was observed (odds ratios = 2.14-4.13; P-values = 0.012 to <0.001). This haplotype is characterized by the presence of C4A null alleles and a solitary short C4B gene linked to the TNF2 allele of the promoter for TNFA gene. This haplotype occurred more frequently in the ever smokers than in the never smokers [odds ratio: 4.97 (1.96-12.62); P = 0.001], and such associations were stronger in women (odds ratio = 13.6) than in men (odds ratio = 2.79). An independent study of complement C4 protein polymorphism and smoking habits in Icelandic subjects (n = 351) yielded similar and confirmative results. Considering the documented link between olfactory stimuli and smoking in females, and the presence of a cluster of odorant receptor genes close to the MHC class I region, our findings implicate a potential role of the MHC-linked olfactory receptor genes in the initiation of smoking. 相似文献
994.
In the adult forebrain, new neuroblasts constantly migrate from the subventricular zone along the rostral migratory stream to the olfactory bulb, where many become neurons. It is unclear whether this process is different in commonly used mouse strains and whether it is related to olfactory function. Adult male BALB/c, C57BL/6, and 129/S1 (formerly 129SV) mice were tested for olfactory sensitivity plus discrimination, using male mouse urine from the two other strains. BALB/c mice had the greatest olfactory sensitivity, followed by 129/S1, and C57BL/6 mice, by an order of magnitude each. Newly formed cells were pulse-labeled for 3 h with i.p. 5-bromo-2'-deoxyuridine (BrdU) injections and the animals analyzed 24 h later. In 129/S1 mice, a greater proportion of neuroblasts were present closer to the olfactory bulb than in BALB/c mice, followed by C57BL/6 mice. The total number of BrdU-labeled cells did not differ, suggesting differences in migration and not proliferation. The impaired olfactory function in C57BL/6 mice might be caused by the reduced number of neuroblasts that reach the olfactory bulbs. However, olfactory function in BALB/c and 129/S1 mice did not correlate with their putative migration speed, suggesting a more complex nature of cellular processes that contribute to olfactory function. These results caution against comparing studies of olfactory function or neural precursors that use different strains of mice, and question the use of C57BL/6 mice as a "normal" strain or as transgenic background. Perhaps more importantly, the results point to an opportunity to identify genes that regulate olfactory function and neuroblast behavior. 相似文献
995.
Cytomegaloviruses encode homologs of cellular immune effector proteins, including chemokines (CKs) and CK receptor-like G protein-coupled receptors (GPCRs). Sequence of the guinea pig cytomegalovirus (GPCMV) genome identified an open reading frame (ORF) which predicted a 101 amino acid (aa) protein with homology to the macrophage inflammatory protein (MIP) subfamily of CC (β) CKs, designated GPCMV-MIP. To assess functionality of this CK, recombinant GPCMV-MIP was expressed in HEK293 cells and assayed for its ability to bind to and functionally interact with a variety of GPCRs. Specific signaling was observed with the hCCR1 receptor, which could be blocked with hMIP −1α in competition experiments. Migration assays revealed that GPCMV-MIP was able to induce chemotaxis in hCCR1-L1.2 cells. Antisera raised against a GST-MIP fusion protein immunoprecipitated species of ∼12 and 10 kDa from GPCMV-inoculated tissue culture lysates, and convalescent antiserum from GPCMV-infected animals was immunoreactive with GST-MIP by ELISA assay. These results represent the first substantive in vitro characterization of a functional CC CK encoded by a cytomegalovirus. 相似文献
996.
997.
Background
The effect of the changes in the femoral posterior condylar offset (PCO) on anterior–posterior (AP) translation and internal–external (IE) rotation in cruciate-retaining (CR) and posterior-stabilized (PS) total knee arthroplasty (TKA) remains unknown. The purpose of this study was to compare the kinematics in CR and PS TKA with respect to the difference in prosthetic design and PCO change through a computational simulation.Methods
We developed three-dimensional finite element models with the different PCOs of ± 1, ± 2 and ± 3?mm in the posterior direction using CR and PS TKA. We performed the simulation with different PCOs under a deep knee bend condition and evaluated the kinematics for the AP and IE in CR and PS TKA.Results
The more tibiofemoral (TF) translation in the posterior direction was found as PCO translated in posterior direction for both CR and PS TKA compared to the neutral position. However, the change of the AP translation with respect to the PCO change in CR TKA was greater than PS TKA. The more TF external rotation was found as PCO translated in the anterior direction for both CR and PS TKA compared to the neutral position. However, unlike the TF translation, the TF rotation was not influenced by the PCO change in both CR and PS TKA.Conclusion
The PCO magnitude was influenced by a postoperative change in the kinematics in CR TKA although a relatively smaller effect was observed in PS TKA. Hence, surgeons should be aware of the PCO change, especially for CR TKA. 相似文献998.
Overexpression of S100A4 is closely related to the aggressiveness of gastric cancer 总被引:25,自引:0,他引:25
Cho YG Nam SW Kim TY Kim YS Kim CJ Park JY Lee JH Kim HS Lee JW Park CH Song YH Lee SH Yoo NJ Lee JY Park WS 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(5):539-545
Elevated levels of the calcium-binding protein S100A4 cause metastasis of benign rat mammary tumor cells. To investigate whether S100A4 plays an important role in the invasion and metastasis of gastric cancers, we examined the gene mutations in the coding regions and expression patterns of the S100A4 in gastric adenocarcinoma in Korea. Moderate to strong expression of S100A4 was found in 53 (68.8%) of the 77 gastric adenocarcinomas, whilst normal gastric epithelium either failed to stain or showed weak staining. Interestingly, S100A4 expression was more frequently observed in gastric cancer patients with advanced gastric cancer (p=0.039), positive lymph node metastasis (p=0.001), and peritoneal dissemination (p=0.022). No gene mutations were found in the analyzed genomic area in 77 gastric adenocarcinomas and 15 gastric cancer cell lines. We found one single nucleotide polymorphism without an amino acid change, A99G, in two cases. These data suggest that the overexpression of S100A4 may be closely related to the aggressiveness of gastric cancer in Korea. 相似文献
999.
Perivascular epithelioid cell tumor of the uterus: immunohistochemical, ultrastructural and molecular study 总被引:1,自引:0,他引:1
A case of perivascular epithelioid cell tumor of the uterus is reported, occurring in a 32-year-old woman. The tumor (8.0 cm in dimension) showed exophytic growth from the outer half of the myometrium. Histopathologically, the tumor was composed of thick blood vessels and perivascular epithelioid cells. The neoplastic cells were strongly immunoreactive for HMB45 antigen, CD117 (c-kit), vimentin and the progesterone receptor, but completely negative for S-100 protein, smooth muscle actin, desmin, CD34, the estrogen receptor and p16. The Ki-67 labeling index was low (1.25%). Ultrastructurally, the neoplastic cells had numerous premelanosomes with some glycogen deposits. Single-stranded DNA conformational polymorphism of p53 and methylation-specific polymerase chain reaction of p16 revealed negative results. Definite melanosomes on electron microscopic analysis and coexpression of HMB45 antigen and stem cell factor receptor (CD117) may provide the clue to understanding perivascular epithelioid cell tumor because angiomyolipoma also coexpresses HMB45 antigen and CD117. 相似文献
1000.