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51.
52.
A laparoscopic cholecystectomy (LC) was successfully performed on a 61-year-old man who had undergone coronary artery bypass grafting (CABG) using the right gastroepiploic artery (RGEA). He complained of right hypochondralgia 20 days after CABG. Gallstones were diagnosed and a cholecystectomy was performed 9 months after CABG. Under general anesthesia, the operation was performed using a pneumoperitonium. When a laparoscope was inserted, the RGEA pedicle could be clearly recognized. The pedicle obstructed the operating field and made the working space narrower than usual. No ST changes on the electrocardiogram were seen during LC, especially during the initiation of pneumoperitonium, the insertion of the ports, or when retracting the gallbladder. The postoperative course was uneventful. To avoid complications, care should be taken not to stretch the RGEA pedicle during LC, and careful monitoring of the electrocardiogram is also necessary. It is difficult to view the operating field and the RGEA pedicle together. It is therefore better to insert another laparoscope for concomitant monitoring of the RGEA pedicle. Received: June 25, 2001 / Accepted: January 8, 2002  相似文献   
53.
Background/Purpose: Mucins are high molecular weight glycoproteins that have oligosaccharides attached to the apomucin protein backbone by O-glycosidic linkages. Here, we report the expression of MUC1 mucin (membrane-bound mucin), MUC2 mucin (intestinal-type secretory mucin), and MUC5AC mucin (gastric-type secretory mucin) in invasive ductal carcinomas (IDCs; n= 46) and intraductal papillary-mucinous neoplasms (IPMNs; n= 33) of the pancreas, and the relationship of this expression with malignant potential. Methods: To clarify the precise expression pattern of mucins in IPMNs, we classified IPMNs into three histologic subtypes; IPMN-dark cell type (n= 19), IPMN-clear cell type (n= 10), and IPMN-compact cell type (n= 4). Results: IDC, with a poor outcome, showed a pattern of MUC1(+), MUC2(−), and MUC5AC(+ or −). In contrast, IPMN-dark cell type tumors, with a fairly favorable outcome, showed a pattern of MUC1(−), MUC2(+), and MUC5AC(+), and IPMN-clear cell type tumors, with a favorable outcome, showed a pattern of MUC1(−), MUC2(−), and MUC5AC(+). On the other hand, IPMN-compact cell type tumors showed a pattern of MUC1(+), MUC2(−), and MUC5AC(+). In IPMN-dark cell type tumors with carcinomatous change showing invasive growth, the invasive areas acquired a characteristic of MUC1 expression that was usually seen in IDC, although their main noninvasive lesions showed no MUC1 expression. The IPMN-compact cell type tumors usually showed high cellular atypia and frequent MUC1 expression, even in the noninvasive areas. Conclusions: Our study of the mucin expression pattern in IDC and IPMN shows that this pattern may be related to the biological behavior of pancreatic tumors and their malignant potential. Received: May 11, 2001 / Accepted: September 26, 2001  相似文献   
54.
We have developed a liver metastatic model of human colon cancer using severe combined immunodeficient (SCID) mice. Liver metastases were observed in all the SCID mice on day 28 after intrasplenic injection with 5 × 106 dissociated tumor cells of COL-2-JCK, a human colon cancer strain serially transplanted in nude mice. When this model was applied for chemotherapeutic experiments, 5-fluorouracil (5-FU) demonstrated significant antitumor effects in preventing liver metastases, whereas the efficacy of 5-FU was limited in the currently used sc-ip chemosensitivity assay in nude mice. When the human LDH-5 isozyme was evaluated in the homogenized metastatic liver tissue of SCID mice, a good correlation was obtained between the liver tumor weights and LDH-5 isozyme, suggesting that it could be a promising quantitative indicator for metastases. This model would be useful for further studies on the treatment of liver metastases of colon cancer. © 1993 Wiley-Liss, Inc.  相似文献   
55.
We measured bone mineral density (BMD) in the radius by dual energy X-ray absorptiometry in 34 patients with rheumatoid arthritis (RA) and in 40 healthy controls. The BMD in RA patients in their fifties and sixties, but not in their forties and seventies, was significantly lower than that in the control subjects. The decrease in total radial BMD correlated with grip strength, RA activity and RA stage. The de crease in distal radial BMD correlated with RA activity, but not with grip strength. The levels of serum parathyroid hormone, alkaline phosphatase, and urinary hydroxyproline/creatinine were significantly higher in the patients. From these findings, we suggest that the bone loss in RA patients is affected by severity of inflammation, disuse, postmenopausal osteoporosis and secondary hyperparathyroidism.  相似文献   
56.
Background. 5-Fluorouracil remains a key drug in the treatment of colorectal cancer, and the development of a simple and effective test for selecting patients likely to benefit from postoperative adjuvant chemotherapy is an important objective. Aim of the Study. This study aimed to clarify the feasibility of measuring apoptotic cell rate (AI%) in tumor after short-term oral 5-fluorouracil administration prior to surgery with the objective of establishing a simpler method to test for sensitivity. Methods. Forty-five colorectal cancer patients were allocated to two groups, and 21 patients were given oral 5-FU for 3 d prior to surgery. The AI% in surgical specimen, detected by TUNEL staining, was compared in the 5-FU-loaded and control groups. The correlation of AI% with 5-FU metabolic enzyme mRNA levels in tumor was also evaluated. Results. The AI% was significantly higher in the tumor tissue of patients receiving 5-FU than in the control group (p<0.0005). Although insignificant, thymidylate synthase mRNA level and orotate phosphoribosyl transferase mRNA demonstrated a weak positive correlation with AI%. Conclusions. The AI% measurement in tumor tissue following a 5-FU oral load for 3 d prior to surgery was feasible. It remains to be elucidated if this measurement as a new 5-FU sensitivity test reflects the prognosis with 5-FU-based postoperative adjuvant chemotherapy.  相似文献   
57.
Pulmonary vascular resistance drops sharply within a few minutes after birth for the survival of neonates. A majority of this resistance is caused by "pulmonary vascular bed" or vessel lacking smooth muscle cells. Heparin is known to promote proliferation and development of endothelial cells and to subsequently decrease their overall vascular resistance, but its detailed features remained unknown. Therefore, in this study we treated neonatal rabbits with heparin, protamine (antagonist of heparin), or saline, and evaluated histopathological features of vascular endothelial cells using two different types of computer assisted image analysis, i.e., CAS200 and NIH image. These two systems detected the percentage of vascular endothelial area per fields (VA) and CD31-positive area per total area of tissue following subtraction of background stain. CD31 was used as an endothelial cell marker. Heparin treated rabbits were associated with significant decrement of pulmonary/systemic artery pressure (Pp/Ps) (21.0 +/- 6.0%) compared to protamine (29.9 +/- 6.1%) or saline (29.4 +/- 3.0%) treated animals. The values of VA obtained by the two image analyses (CAS200 and NIH image) were significantly increased in heparin treated animals (38.4 +/- 3.2% determined by CAS200 and 24.0 +/- 1.3% by NIH image) compared to protamine (30.2 +/- 3.9% and 19.2 +/- 1.8%) or saline (33.2 +/- 1.5% and 20.8 +/- 3.8%) treated animals on 14th day of treatment. The present study indicates that heparin accelerates pulmonary vascular bed development probably by increasing the number and volume of endothelial cells, which subsequently contributes to the decrease in pulmonary vascular resistance.  相似文献   
58.
59.
We examined the effect of tributyltin (TBT) on reproduction of the pearl oyster (Pinctada fucata martensii). In a maternal exposure test, five female pearl oysters were exposed to TBT at measured concentrations of 0 (control), 0.092, or 0.191 microg/L at 25 degreesC for one week, and the embryo developmental success (the ratio of normal D-larvae to all larvae) was measured. The embryo developmental success was significantly decreased in the 0.191-microg/L treatment group (65.5%) compared to that in the control group (82.5%; p = 0.031). Concentrations of TBT in the ovary reached 0.088 microg/g in the 0.191-microg/L treatment group. In a waterborne exposure test, inseminated eggs were exposed to TBT at measured concentrations of 0 (control), 0.020, 0.045, 0.091, 0.192, or 0.374 microg/L for 24 h. The embryo developmental success also was significantly decreased in the 0.192-microg/L treatment group (78.3%; p = 0.020) and no development at all was observed in the 0.374-microg/L treatment group compared with that in the control group (95.4%). These results clearly demonstrate that TBT accumulating in the bodies of bivalves has the potential to inhibit reproduction.  相似文献   
60.
BACKGROUND: Although several kinds of evidence suggest that glycosaminoglycans (GAGs) and proteoglycans (PGs) may contribute to the development of beta2-microglobulin-related (Abeta2m) amyloidosis, the precise roles of these molecules for the development of Abeta2m amyloidosis are poorly understood. METHODS: We investigated the effects of GAGs and PGs on the depolymerization of Abeta2m amyloid fibrils at a neutral pH, as well as on the formation of the fibrils at an acidic pH in vitro, using fluorescence spectroscopy with thioflavin T and electron microscopy. RESULTS: Depolymerization of Abeta2m amyloid fibrils at pH 7.5 at 37 degrees C was inhibited dose-dependently by the presence of some GAGs (heparin, dermatan sulfate, or heparan sulfate) or PGs (biglycan, decorin, or keratan sulfate proteoglycan). Electron microscopy revealed that a significant amount of Abeta2m amyloid fibrils remained in the reaction mixture with some lateral aggregation. Second, when monomeric beta2m was incubated with aggrecan, biglycan, decorin, or heparin at pH 2.5 at 37 degrees C for up to 21 days, the thioflavin T fluorescence increased depending on dose and time. Electron microscopy revealed the formation of rigid and straight fibrils similar to Abeta2m amyloid fibrils in beta2m incubated with biglycan for 21 days. CONCLUSION: These results suggest that some GAGs and PGs could enhance the deposition of Abeta2m amyloid fibrils in vivo, possibly by binding directly to the surface of the fibrils and stabilizing the conformation of beta2m in the fibrils, as well as by acting as a scaffold for the polymerization of beta2m into the fibrils.  相似文献   
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