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Prostaglandin E1-induced hypotension (25% reduction from the preadministration level in mean arterial pressure) was applied to thirteen patients. Eight patients among them were operated in the supine position (group I) and other five in the prone position (group II). The maintenance dose of PGE1 was considerably lower in group II than in group I (0.067µg·kg–1·min–1 vs. 0.119µg·kg–1·min–1). In group I, there was a significant increase in CI, with a significant decrease in SVRI and PVRI during PGE1-induced hypotension. Such a high dose of PGE1 (0.119µg·kg–1·min–1) was considered to have a direct dilating action on the systemic resistance bed as well as on the pulmonary vasculature. It was considered that the suppression of hypoxic pulmonary vasoconstriction could be a mechanism to increase venous admixture during PGE1-induced hypotension. In group II, there was no significant increase in CI, and no significant decrease in SVRI and PVRI. PGE1-induced hypotension can be safely applied to the anesthetized patients, but we should be careful to apply it to the patients in the prone position, because lower dose of PGE1 can induce severe hypotension, which is not accompanied by the increase in CI as occures in the patients in the supine position.(Hirose M, Yoda K, Sakai K, et al.: Comparative Study on the cardio-respiratory change during prostaglandin E1-induced hypotention in the patients in the supine and prone position. J Anesth 5: 30–35, 1991)  相似文献   
94.
PURPOSE: To evaluate the prognostic value of vascular endothelial growth factor (VEGF)-D and VEGF receptor (VEGFR)-3 in endometrial carcinoma. EXPERIMENTAL DESIGN: We assessed the levels of immunoreactivity for VEGF-D and VEGFR-3 in 71 endometrial carcinomas, 14 complex atypical endometrial hyperplasias, and 16 normal endometria by immunohistochemistry. RESULTS: VEGF-D was stained in both tumor cells and adjacent stromal cells. VEGFR-3 was stained in both tumor cells and adjacent endothelial cells. Immunoreactivity for VEGF-D in tumor cells and adjacent stromal cells became significantly stronger as lesions progressed from normal endometrium to advanced carcinoma. Similarly, immunoreactivity for VEGFR-3 in tumor cells and adjacent endothelial cells was significantly greater as lesions progressed from normal endometrium to advanced carcinoma. A strong correlation was found between high levels of VEGF-D immunoreactivity in carcinoma cells and VEGFR-3 in both carcinoma cells and adjacent endothelial cells. Similarly, high levels of VEGF-D immunoreactivity in stromal cells were significantly correlated with those of VEGFR-3 in both carcinoma cells and endothelial cells. High levels of VEGF-D in carcinoma cells and stromal cells, as well as those of VEGFR-3 in carcinoma cells and endothelial cells, were significantly related to myometrial invasion and lymph node metastasis. A strong correlation was found between poor survival and high levels of VEGF-D in both carcinoma cells and stromal cells and between poor survival and high levels of VEGFR-3 in carcinoma cells. Moreover, the high levels of VEGF-D in stromal cells and VEGFR-3 in carcinoma cells were independent prognostic factors in endometrial carcinoma. CONCLUSIONS: The presence of VEGF-D and VEGFR-3 in endometrial carcinoma may predict myometrial invasion and lymph node metastasis and may prospectively identify patients who are at increased risk for poor outcome. In addition, VEGF-D and VEGFR-3 may be promising targets for new therapeutic strategies in endometrial carcinoma.  相似文献   
95.
Plasticity of polypoidal lesions in polypoidal choroidal vasculopathy   总被引:2,自引:0,他引:2  
Purpose The aim of this study was to describe the clinical course in a patient with polypoidal choroidal vasculopathy (PCV).Methods A 68-year-old man with PCV in the left eye was followed up by means of routine examinations including fluorescein angiography and indocyanine green angiography for over 60 months.Results Throughout the follow-up period, the patient experienced repeated lesions in the macula, such as serosanguineous detachment of the retinal pigment epithelium and neurosensory retina, but retained good visual acuity. Indocyanine green angiography disclosed spontaneous regression of polypoidal vessels followed by significant changes in the choroidal circulation: a group of polypoidal structures disappeared, and after several months a small choroidal vessel became apparent that was distant from the previously observed polypoidal structure rather than representing an extension of the original lesion.Conclusion The clinical observation suggests that in some cases of PCV the choroidal vasculature may be altered with time, in that some vessels in the inner choroid and even the choriocapillaris may close and collateral vessels and/or new vessels may develop to form complex such as that described here.  相似文献   
96.
We investigated influx and efflux transporters involved in blood-brain barrier transport of the nonsedative H1-antagonist epinastine. The basal-to-apical transport of [14C]epinastine was markedly higher than that in the opposite direction in LLC-GA5-COL150 cells stably transfected with human multidrug resistance (MDR)1 gene. The brain-to-plasma concentration ratio of [14C]epinastine in mdr1a/b(-/-) mice was 3.2 times higher than that in wild-type mice. The uptake of both [3H]mepyramine and [14C]epinastine into immortalized rat brain capillary endothelial cells (RBEC)1 showed temperature and concentration dependence. The kinetic parameters, K(m), V(max), and uptake clearance (V(max)/K(m)), of the initial uptake of [3H]mepyramine and [14C]epinastine by RBEC1 were 150 microM, 41.8 nmol/min/mg protein, and 279 microl/min/mg protein for mepyramine and 10.0 mM, 339 nmol/min/mg protein, and 33.9 microl/min/mg protein for epinastine, respectively. The uptake of [3H]mepyramine and [14C]epinastine by RBEC1 was inhibited by organic cations such as quinidine, amantadine, and verapamil, but not by other organic cations, tetraethyl ammonium, guanidine, and carnitine. Organic anions such as benzoic acid, estrone-3-sulfate, taurocholate, and neutral digoxin were not inhibitory. Furthermore, some cationic H1 antagonists (chlorpheniramine, cyproheptadine, ketotifen, and desloratadine) inhibited the [3H]mepyramine and [14C]epinastine uptake into RBEC1. In conclusion, the present study demonstrated that the combination of efficient efflux transport by P-glycoprotein and poor uptake by the influx transporter, which is identical with that responsible for the uptake of mepyramine, account for the low brain distribution of epinastine.  相似文献   
97.
To determine the reversibility of hematological and pathological changes in spleen induced by sub-chronic administration of chlorpropham (CIPC), male F344 rats were given CIPC in the diet at 0, 600, 3000 or 15,000 ppm for 13 weeks (administration period) and then were given standard (0 ppm) diet for 10 weeks (recovery period). At 0, 1, 2, 4 or 10 weeks in the recovery period, 5 rats in each groups were examined for hematology and pathology. At the end of CIPC administration, dose-dependent and significant methemoglobinemia, anemia, splenomegaly and pathological lesions indicating hemolytic anemia were observed in all the treated groups. The hematological changes, congestion of red pulp, lymphoid atrophy, increased extramedullary hematopoiesis in spleen and hematopoietic cell hyperplasia in bone marrow were diminished during the 10 weeks recovery period. However, increased hemosiderin deposition and capsular fibrosis in spleen of the treated groups remained at the end of recovery period. The results indicated that hematological changes induced by sub-chronic administration of CIPC were reversible but hemosiderin deposition and fibrosis in spleen were not reversible in the recovery period examined, suggesting the significance of splenic lesion in CIPC-toxicity.  相似文献   
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99.
To examine the possible association of dietary fat and fatty acids with breast cancer risk in a population with a low total fat intake and a high consumption of fish, we analyzed data from the Japan Collaborative Cohort (JACC) Study. From 1988 to 1990, 26 291 women aged 40-79 years completed a questionnaire on dietary and other factors. Intakes of fat or fatty acids were estimated by using a food frequency questionnaire. Rate ratios (RR) were computed by fitting proportional hazards models. During the mean follow-up of 7.6 years, 129 breast cancer cases were documented. We found no clear association of total fat intake with breast cancer risk; the multivariate-adjusted RR across quartiles were 1.00, 1.29, 0.95, and 0.80 (95% confidence interval [CI] 0.46-1.38). A significant decrease in the risk was detected for the highest quartile of intake compared with the lowest for fish fat and long-chain n-3 fatty acids; the RR were 0.56 (95% CI 0.33-0.94) and 0.50 (0.30-0.85), respectively. A decreasing trend in risk was also suggested with an increasing intake of saturated fatty acids (trend P = 0.066). Among postmenopausal women at baseline, the highest quartile of vegetable fat intake was associated with a 2.08-fold increase in risk (95% CI 1.05-4.13). This prospective study did not support any increase in the risk of breast cancer associated with total or saturated fat intake, but it suggested the protective effects of the long-chain n-3 fatty acids that are abundant in fish.  相似文献   
100.
Accumulating evidence suggests that post‐diagnostic insulin levels may influence colorectal cancer (CRC) survival. Yet, no previous study has examined CRC survival in relation to a post‐diagnostic diet rich in foods that increase post‐prandial insulin levels. We hypothesized that glycemic and insulin scores (index or load; derived from food frequency questionnaire data) may be associated with survival from specific CRC subtypes sensitive to the insulin signaling pathway. We prospectively followed 1,160 CRC patients from the Nurses' Health Study (1980–2012) and Health Professionals Follow‐Up Study (1986–2012), resulting in 266 CRC deaths in 10,235 person‐years. CRC subtypes were defined by seven tumor biomarkers (KRAS, BRAF, PIK3CA mutations, and IRS1, IRS2, FASN and CTNNB1 expression) implicated in the insulin signaling pathway. For overall CRC and each subtype, hazard ratio (HR) and 95% confidence interval (95% CI) for an increase of one standard deviation in each of glycemic and insulin scores were estimated using time‐dependent Cox proportional hazards model. We found that insulin scores, but not glycemic scores, were positively associated with CRC mortality (HR = 1.19, 95% CI = 1.02–1.38 for index; HR = 1.23, 95% CI = 1.04–1.47 for load). The significant positive associations appeared more pronounced among PIK3CA wild‐type cases and FASN‐negative cases, with HR ranging from 1.36 to 1.60 across insulin scores. However, we did not observe statistically significant interactions of insulin scores with PIK3CA, FASN, or any other tumor marker (p interaction > 0.12). While additional studies are needed for definitive evidence, a high‐insulinogenic diet after CRC diagnosis may contribute to worse CRC survival.  相似文献   
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