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91.
The epithelium in kidneys and urinary bladders contain CK18 as in liver cells. The modulation of cytokeratin 18 during tumor transformation in hepatoma had been previously recognized through a series of biochemical and immunological approaches. A 14 KD hepatoma related molecules was found in the previous studies. We would like to utilize the hepatoma transformation model to study the changes in CK18 in transitional cell carcinoma, using immunoblotting and western blotting techniques. The result is that transitional cell carcinoma retain their CK18 molecule. Furthermore, CK18 related molecules similar to those seen in hepatoma also present in transitional cell carcinoma. The conclusions are transitional cell carcinoma contains CK18 related proteins similar to those seen in hepatoma tissues. We suggest that this element would be responsible for the change during the malignant transformation processes.  相似文献   
92.
A stratified, unselected sample of 30 patients who underwent revision total hip arthroplasty between 1990 and 1992 for whom complete clinical and financial data were available was studied. Clinical data included age, gender, diagnosis, length of stay, operative time and blood loss. Financial data included cost of implants, bone graft and accessories, hospital charge, and surgeon reimbursement. Results were compared with the results of an analogous group of 50 patients who underwent revision total hip arthroplasty at the same institution between 1995 and 1997. Cases were classified as simple (involving revision of only acetabular liner and/or femoral head), routine (revision of acetabular and/or femoral components), or complex (major structural graft, antiprotrusio cage, impacted grafting). For patients undergoing routine revision total hip arthroplasty, a dramatic decline of 52% occurred in length of stay during the 5-year span (10.7 days to 5.1 days). The average operative time also declined significantly (238 minutes to 199 minutes) as did the average implant cost ($4349 to $2827). Despite this, the average hospital charge increased 16% ($29,666 to $34,328). There was a significant and dramatic 35% decline in surgeon reimbursement ($3240 to $2178). There was no significant difference in surgeon reimbursement between simple, routine, and complex total hip arthroplasty. Patients who underwent complex procedures had a significantly greater length of stay (7.3 versus 5.1 days) and operative time (297 versus 199 minutes). The hospital charge was dramatically higher for patients undergoing complex procedures ($51,290 versus $34,328) but the surgeon reimbursement was lower on average, although not statistically significant ($1926 versus $2178). There was a significant increase in the number and complexity of revision total hip arthroplasties between the two periods. Significant decreases were achieved in length of stay, operating room time, and implant cost. Benefits from these changes were accrued to the hospital but not the surgeon because hospital costs decreased significantly whereas surgeon reimbursements declined dramatically.  相似文献   
93.
BACKGROUND: Controversies regarding how urgent bowel perforation should be diagnosed and treated exist in recent reports. The approach for early diagnosis is also debatable. The purposes of this study were to evaluate the relationship between treatment delay and outcome of small bowel perforation after blunt abdominal trauma and to determine the best assessment plan for the diagnosis of this injury. METHODS: One hundred eleven consecutive patients with small bowel perforations caused by blunt abdominal trauma were retrospectively reviewed. The patients were divided into four groups according to the time interval between injury and surgery. Hospital stay, time to resume oral intake, and mortality and morbidity rates were compared between groups. Physical signs, laboratory and computed tomographic findings, and the results of diagnostic peritoneal lavage were analyzed to find the most sensitive and specific test for early diagnosis of small bowel perforation. RESULTS: Delay in surgery for more than 24 hours did not significantly increase the mortality with modern method of treatment; however, complications increased dramatically. Hospital stay and time to resume oral intake increased significantly when surgery was delayed for more than 24 hours. Abdominal tenderness was a common finding, but it was not specific for bowel perforation. Only 40% of the computed tomographic scans were diagnostic for bowel perforations: 50% of them showed suggestive signs, and 10% were considered as negative. Persistence of abdominal signs indicated peritoneal lavage. By using cell count ratio in diagnostic peritoneal lavage and/or increased lavage amylase activity, presence of particulate matter and/or bacteria in the lavage fluid, all patients with intraperitoneal bowel perforation were diagnosed accurately before operation. CONCLUSION: Small bowel perforation has low mortality and complication rates if it is treated earlier than 24 hours after injury. The principle of "rushing to the operation suite" for a stable blunt abdominal trauma patients without detailed systemic examination is not justified. The priority of treatment for the small bowel perforation should be lower than the limb-threatening injuries. Diagnostic peritoneal lavage provides high sensitivity and specificity rates for the diagnosis of small bowel perforation if a specially designed positive criterion is applied.  相似文献   
94.
Knee dislocation: treatment of high-velocity knee dislocation   总被引:9,自引:0,他引:9  
Yeh WL  Tu YK  Su JY  Hsu RW 《The Journal of trauma》1999,46(4):693-701
BACKGROUND: We report the outcomes of patients treated with a new arthroscopic treatment modality for knee dislocation after high-velocity trauma. METHODS: Twenty-three patients (12 men, 11 women; 25 knees) with traumatic knee dislocation were treated with this technique. Under arthroscopy with gravity inflow irrigation, the ruptured posterior cruciate ligament was reconstructed with a patellar bone-tendon-bone graft, and the anterior cruciate ligament was debrided subacutely. The collateral ligament, meniscus, and capsules were repaired through additional incisions. RESULTS: The average interval between injury and surgery was 11.1+/-5 days (range, 5 to 25 days). After a mean follow-up period of 27.2+/-7.86 months, the mean extension was 1+/-2 degrees and the average flexion was 129.6+/-4.91 degrees. The mean Lysholm score was 84. There were no major complications. CONCLUSION: Arthroscopic posterior cruciate ligament reconstruction seems to be an effective treatment for traumatic knee dislocation.  相似文献   
95.
Hsu L  Aragaki C  Quiaoit F  Wang X  Xu X  Zhao LP 《Genetic epidemiology》1999,17(Z1):S621-S626
A genome-wide scan of a simulated data set for fictitious disease genes was conducted using both semiparametric and nonparametric methods. The semiparametric model-based method, which tests for linkage/linkage disequilibrium separately and together, correctly identified all three underlying disease loci along with two false positives through the linkage analysis. However, the nonparametric model-free method which tests combined linkage/linkage disequilibrium, failed to yield any results due to the lack of linkage disequilibrium information in the data.  相似文献   
96.
PURPOSE: Previous studies suggest that proteins associated with the apical junctional complex (AJC) play essential roles in the development, maintenance and regulation of barrier function in transport epithelium and vascular endothelium. The goal of this study is to identify and determine the spatial organization of several major AJC-associated proteins in normal human and feline corneal endothelium. METHODS: Fresh corneal tissue was obtained from 4 recipient buttons removed during penetrating keratoplasty (two from keratoconus patients, and two from patients with post-traumatic stromal scarring) as well as from 16 cat eyes. En bloc double- and triple-labeling of corneas was performed using phalloidin, and mouse, rat or rabbit antibodies to ZO-1, occludin, pan-cadherin, alpha-catenin, beta-catenin and plakoglobin (gamma-catenin). The 3-D localization of the proteins was then determined in situ using laser confocal microscopy. RESULTS: Similar staining patterns were obtained for the corneal endothelium of normal cat corneas and fresh human buttons. Apically, f-actin was arranged into dense peripheral bands (DPB) in individual cells that were separated from those in adjacent cells. Diffuse phalloidin staining also extended from the DPB into the cytoplasm apically. Although weaker, phalloidin staining also appeared to be associated with the basolateral cell borders. The adherens junction protein, cadherin, formed a thin pericellular band at the apical cell junctions between the DPB. In addition, cadherin staining also appeared to extend along the basolateral cell borders in a convoluted pattern. Staining for alpha-catenin, beta-catenin and plakoglobin each showed a nearly identical organization as cadherin. ZO-1 formed a single apical band that was localized between the DPB; however, no basolateral ZO-1 staining was detected. Interestingly, the distribution of ZO-1 was discontinuous around the cell, with the largest gaps occurring at the Y-junctions between adjacent endothelial cells. Positive staining for occludin was not detected in either human or feline corneal endothelium. CONCLUSIONS: The composition and organization of the AJC of corneal endothelium appears to be different from that of classical transport epithelia; these findings may be related to functional differences between these two cell types.  相似文献   
97.
It has been reported that nonsteroidal anti-inflammatory drugs (NSAIDs) suppress bone repair and bone remodeling but only mildly inhibit bone mineralization at the earlier stage of the repair process. We proposed that the proliferation and/or the earlier stage of differentiation of osteoblasts may be affected by NSAIDs. This study was designed to investigate whether NSAIDs affect the proliferation and/or differentiation of osteoblasts and whether these effects are prostaglandin (PG) mediated. The effects of PGE1 and PGE2, indomethacin, and ketorolac on thymidine incorporation, cell count, intracellular alkaline phosphatase (ALP) activity, and Type I collagen content in osteoblast-enriched cultures derived from fetal calvaria were evaluated. The results showed that both PGs and NSAIDs inhibited DNA synthesis and cell mitosis in a time- and concentration-dependent manner. However, intracellular ALP activity and Type I collagen content were stimulated at an earlier stage of differentiation in osteoblasts. These results suggested that (i) the inhibitory effect of ketorolac on osteoblastic proliferation contributes to its suppressive effects on bone repair and remodeling in vivo; (ii) PGEs and NSAIDs may be involved in matrix maturation and biologic bone mineralization in the earlier stage of osteoblast differentiation; and (iii) the effects of ketorolac and indomethacin on cell proliferation and differentiation may not be through the inhibition of the synthesis of PGE1 or PGE2.  相似文献   
98.
The present study characterized Chinese hamster ovary cells overexpressing a human intestinal peptide transporter, CHO/hPEPT1 cells, as an in vitro model for peptidomimetic drugs. The kinetic parameters of Gly-Sar uptake were determined in three different cell culture systems such as untransfected CHO cells (CHO-K1), transfected CHO cells (CHO/hPEPT1) and Caco-2 cells. Vmax in CHO/hPEPT1 cells was approximately 3-fold higher than those in Caco-2 cells and CHO-K1 cells, while Km values were similar in all cases. The uptake of beta-lactam antibiotics in CHO/hPEPT1 cells was three to twelve fold higher than that in CHO-K1 cells, indicating that CHO/hPEPT1 cells significantly enhanced the peptide transport activity. However, amino acid drugs also exhibited high cellular uptake in both CHO-K1 and CHO/hPEPT1 cells due to the high background level of amino acid transporters. Thus, cellular uptake study in CHO/hPEPT1 cells is not sensitive enough to distinguish the peptidyl drugs from amino acid drugs. The potential of CHO/hPEPT1 cells as an in vitro model for peptidomimetic drugs was also examined through the inhibition study on Gly-Sar uptake. Peptidomimetic drugs such as beta-lactam antibiotics and enalapril significantly inhibited Gly-Sar uptake whereas the nonpeptidyl compounds, L-dopa and alpha-methyldopa, did not compete with Gly-Sar for cellular uptake within the therapeutic concentrations. In conclusion, the present study demonstrates the further characterization of CHO/hPEPT1 cells as an uptake model as well as inhibition study and suggests their utility as an alternative in vitro model for drug candidates targeting the hPEPT1 transporter.  相似文献   
99.
Y.-T. Chung  W. Hsu 《Archives of virology》1996,141(12):2457-2464
Summary Sequence analysis within the unique long segment of the bovine herpesvirus 1 (BHV-1; infectious bovine rhinotracheitis virus) genome identified an open reading frame whose deduced protein product of 487 amino acids exhibited homology to alkaline deoxyribonucleases (DNases) of other herpesviruses. To determine this BHV-1 gene product has nuclease activity, the gene designated UL12 was inserted into the vector pET-28a(+) and expressed inEscherichia coli as an oligohistidine-tagged protein. Upon induction with isopropyl -D-thiogalactopyranosideE. coli BL21 (DE3) [pLysS] cells carrying this recombinant plasmid produced a 57-kDa protein, the molecular mass of which was in accordance with the prediction from the DNA sequence. The recombinant UL12 protein purified by nickel-chelating affinity chromatography exhibited both exonuclease and endonuclease activity, each with an alkaline pH optimum.  相似文献   
100.
Degeneration within the hippocampus was examined at the light microscopic level using the Gallyas silver stain two, four or nine months after bilateral transection of the fimbria-fornix and commissural connections. At two or four months after the lesion the strata oriens and radiatum of the subicular end of the CA1 subfields were strongly argyrophilic as was the inner third of the molecular layer of the dentate gyrus. At nine months post-lesion argyrophilia diminished but clearly persisted in the same layers. Electron microscopic examination revealed a large number of electron-dense axon terminals in the argyrophilic areas, most of them making asymmetric synaptic contacts with dendritic spines. These findings suggest that at least a portion of the Schaffer collaterals of the CA3 pyramidal cells and associational collaterals of hilar neurons were in a process of acute degeneration at all time points after the initial surgical trauma. This persistent synaptic reorganization of intrahippocampal circuits may be related to abnormal electrical activity observed several months after fimbria-fornix transection.  相似文献   
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