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61.
62.
This study deals with the quantification of mRNA of basement membrane components (laminin, type IV collagen, heparan sulfate proteoglycan) and type I collagen in focal glomerular sclerosis induced by the aminonucleoside of puromycin (PAN) in rats. PAN (15 mg/100 g B.W.) was injected intraperitoneally to male Sprague-Dawley rats on day 0. On day 22, the right kidney was removed from group II and III. Rats in group III received injections of PAN (5 mg/100 g B.W.) on day 27, 34 and 41. Rats in group II received injections of 0.9% NaCl instead of PAN. Remnant kidneys were removed on days 48, 60 and 80 and processed for RNA isolation and histopathological study. Glomerular RNAs were isolated using guanidinium thiocyanate and then dotted onto nylon membrane. Filters were hybridized with specific cDNA probes and exposed to film for analysis by densitometer. FGS was detected in 70% of glomeruli on day 80 in group II. All the basement membrane components and type I collagen were accumulated in the sclerotic areas. The mRNA coding for laminin and type IV collagen continued to increase in group III till day 80. The mRNA for HSPG decreased when the urinary protein excretion was maximum on day 48, then increased with the remission of proteinuria. The type I collagen mRNA also increased during the course of the FGS. We suggest that decrease of mRNA for HSPG may play an important role in the development of proteinuria in PAN nephrosis and increase of mRNA coding for laminin, type IV collagen and type I collagen may be involved in focal glomerular sclerosis.  相似文献   
63.
BACKGROUND AND METHODS. It is not certain whether patients with Kawasaki disease have a higher death rate than the age-matched healthy population. We therefore undertook a study to investigate this question. Between July 1982 and December 1988, 53 collaborating treatment centers collected data on all patients who had an unequivocal new diagnosis of Kawasaki disease; patients who had recurrent disease or whose first visit to the treatment center occurred more than 14 days after the onset of symptoms were excluded. Patients were followed from the time of the first visit to the treatment center until December 31, 1989, or until death, whichever occurred first. The expected number of deaths was calculated from Japanese vital-statistics data and compared with the number observed. RESULTS. Of 4676 patients who met the eligibility criteria, 4608 (98.5 percent) were followed through either the end of the study or the date of death. Thirteen patients (10 boys and 3 girls) died during the study period. The number of deaths expected was 7.61 (ratio of observed to expected deaths, 1.71; 95 percent confidence interval, 0.91 to 2.92). The ratio was 2.04 (95 percent confidence interval, 0.98 to 3.76) for boys and 1.11 (95 percent confidence interval, 0.23 to 3.23) for girls. During the acute phase of the disease (the first two months after onset), the ratios of observed to expected deaths were higher: 9.86 overall (95 percent confidence interval, 3.95 to 20.31), 13.33 for boys (95 percent confidence interval, 4.89 to 29.07), and 3.85 for girls (95 percent confidence interval, 0.10 to 21.42). After the acute phase, however, both sexes had ratios of observed to expected deaths that were lower than 1, and the difference from the control population was not statistically significant. CONCLUSIONS. The mortality rate among boys with Kawasaki disease in Japan is twice that among healthy boys of the same age, and most deaths occur within two months of diagnosis. The mortality rate among girls with the disease appears similar to that among healthy girls, although the numbers are very small.  相似文献   
64.
Human gastric carcinoma cells from one of three long-term cultured cell lines (HPE-GAC-T) were injected into peritoneal cavities of BALB/c mice. The surviving celss in vivo were collected 3 days later. Following brief cultivation in vitro, those cells were reinjected into mice by the same route. This procedure was repeated 3 times. The cultured cancer cells recovered from the mice on the 3rd passage, at a 92.5% recovery rate, showed xenotransplantability in BALB/C nu/nu mice by subcutaneous injection. This subline (GAC-T.M-2) can be maintained in vitro but not in vivo while maintaining heterotransplantability. Three original cancer cell lines did not show tumorigenicity in nude mice. Animal passages by the same protocol failed to select tumorigenic sublines from the other cell lines (HPE-GAC-2 and -3). Factors affecting tumorigenic capacity of cancer cells in nude mice were studied in vivo and in vitro by comparing the properties of GAC-T.M-2 and parental cancer cells (GAC-T.O). Treatment of the hosts by injection of anti-asialoGM1 antibody or cyclophosphamide, adult thymectomy of BALB/c mice, and 400 rads whole body irradiation did not enhance the growth of either GAC-T.M-2 or -T.O cells. There was no detectable difference between in vitro growth properties of the original and variant cells at a rather high cell density. However, at a low cell density GAC-T.M-2 cells showed a higher cell growth rate and increased [3H] thymidine incorporation and possessed higher colony forming activity in the liquid medium than their parental cells. High dense expression of epidermal growth factor (EGF) receptors was evident equally in both GAC-T cells, however, GAC-T.M-2 cells were more sensitive to down-regulation by EGF in culture. Tumor cells of HPE-GAC-2 and -3 lines expressed minimum amount of EGF receptors on their cell surfaces and were refractory to additional EGF in culture. The results indicate that growth factors and their receptors are responsible for tumorigenicity in nude mice.  相似文献   
65.
We successfully performed arterial embolization of an arteriovenous fistula between the left gastric artery and vein. The increased blood flow in the portal vein via the left gastric vein and the arteriovenous fistula induced severe portal hypertension. After obliteration of the left gastric artery, the arteriovenous fistula was not opacified on angiography and the portal hypertension improved.  相似文献   
66.
To examine the effects of transient hyperprolactinemia on in vitro fertilization and embryo transfer, 61 cycles in 50 euprolactinemic ovulatory women with irreparable tubal diseases were stimulated with clomiphene (CC) alone or CC and human menopausal gonadotropin followed by human chorionic gonadotropin (hCG). Serum prolactin (PRL) increased after hCG administration with peak values of 45.4 +/- 4.2 ng/ml on the day of laparoscopic oocyte aspiration. The highest serum estradiol (E2) concentration was found on the day before PRL peak and serum progesterone (P) began to increase after hCG injection concomitant with the PRL rise. The group having 50 ng/ml or more of PRL (34 cycles) had significantly higher levels of E2 during preovulatory and early luteal phase compared to those of the group having less than 50 ng/ml of PRL (27 cycles) but there was no significant difference between the P levels in the two groups. In the higher PRL group 72 (62.1%) of 116 collected oocytes were fertilized and 6 (20.0%) conceived. In the lower PRL group 45 oocytes (58.4%) of 77 were fertilized and 3 (12.5%) became pregnant. These data suggest that elevated serum PRL concentrations may have no effect on fertilization of oocytes in vitro or embryonic development.  相似文献   
67.
To investigate the relationship between the effects of bone turnover and bone marrow cell development in bone cells, we developed a mouse voluntary climbing exercise model. Climbing exercise increased bone volume and transient osteogenic potential of bone marrow. This model would be suitable for investigating the mechanistic roles of mechanical loading. INTRODUCTION: The relationship between bone mass gain and local bone formation and resorption in mechanically loaded bone is not well understood. MATERIALS AND METHODS: Sixty-five C57BL/6J mice, 8 weeks of age, were assigned to five groups: a baseline control and two groups each of ground control and climbing exercise mice for 2 and 4 weeks. Mice were housed in a 100-cm tower and had to climb toward a bottle placed at the top to drink water. RESULTS: Compared with the ground control, bone mineral density of the left femur increased in the climbing mice at 4 weeks. At 2 and 4 weeks, bone formation rate (BFR/BS) of periosteal surface, the cross-sectional area, and moment of inertia were increased in the climbing mice, whereas BFR/BS and eroded surface (ES/BS) of endosteal surface did not differ. The trabecular bone volume (BV/TV) of the proximal tibia increased in climbing mice, and osteoclast surface (Oc.S/BS) and osteoclast number decreased at 2 weeks. At 4 weeks, there were increases in BV/TV and parameters of bone formation, including mineralized surface, mineral apposition rate, and bone formation rate. In marrow cell cultures from the tibia, the number of alkaline phosphatase+ colony forming units-fibroblastic and the area of mineralized nodule formation in climbing mice were increased, and the number of osteoclast-like TRACP+ multinucleated cells was lower at 2 weeks. At 4 weeks, these parameters recovered to the levels of the ground controls. CONCLUSION: Our results indicate that climbing increased trabecular bone volume and reduced bone resorption, with a subsequent increase in bone formation. Intermittent climbing downregulates marrow osteoclastogenic cells and upregulates osteogenic cells initially, but further exercise seemed to desensitize them. Cortical envelopes were enlarged earlier, but the response seems to differ from trabecular bone.  相似文献   
68.
69.
Leiomyoblastoma has been regarded as a neoplasm of smooth muscle origin. With recent progress in immunohistostaining techniques, many clinicopathological discrepancies have been pointed out about the origin of leiomyoblastoma. It has been claimed that gastrointestinal non-epithelial tumors should be regarded as stromal tumors in order to study their origin. In the present study, we performed various forms of immunohistostaining in seven cases of leiomyoblastoma to determine their origin. One case expressed desmine and muscle specific actin and was considered to be derived from smooth muscle. Four neoplasms expressed X-100 protein (two cases were also NSE positive) and were thought to be derived from the nerve. Two cases were of unknown derivation. These results suggest that the cells of leiomyoblastoma may arise from a primitive to totipotential cell of neural lineages that may anomalously express smooth muscle filaments.  相似文献   
70.
Endoscopic resection has been accepted as the standard treatment for intramucosal gastric tumors of differentiated type. However, the indication was limited to small tumors to achieve en bloc resection and prevent local recurrence in cases of conventional endoscopic mucosal resection (EMR) such as the strip biopsy and the cap technique. To avoid multi‐fragmental resection, we have developed endoscopic submucosal dissection (ESD) as a new endoscopic resection technique. ESD is a remarkable technique, because we make it possible to remove the lesions en bloc regardless of size, shape, coexisting ulcer, and location. However, it is difficult or impossible to resect recurrent tumors en bloc in conventional EMR owing to hard fibrosis, and some patients need laparotomy. Using ESD, we can dissect the submucosal layer as we directly look at the submucosa, and remove the lesion safely and reliably even in cases of hard fibrosis. The key to treatment of recurrent tumors in ESD are as follows: (i) using enough submucosal injection solution (we use a mixture of Glyceol and 1% 1900 kDa hyaluronic acid preparation); (ii) incising the mucosa without fibrosis; (iii) understanding characteristics of various cutting devices, and changing other devices in difficult situations. In these ways we can remove the majority of the recurrent tumors en bloc. Hence, we consider that ESD is a very effective treatment which achieves excellent en bloc and complete resection rates and enables patients with intramucosal gastric tumors to a recurrent‐free survival even in recurrent tumors.  相似文献   
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