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991.
Different T-cell subsets participating in immune responses were detected at a high frequency by a modified virus plaque assay (VPA). By using the modified VPA, different activated T-cell subsets generated in primary immune responses, helper and suppressor T cells participating in antibody formation, and effector T cells involved in the delayed-type hypersensitivity (DTH) reaction were enumerated directly without in vitro antigen stimulation. The frequency of detection in immune systems used was 7.5-17.7 V-PFC/10(3) spleen cells. Although neither helper T cells for antibody formation nor effector T cells for DTH reaction were detected as V-PFC at a high frequency by the original VPA, it was also found in secondary immune response that Lyt 1 positive, antigen-specific helper and effector T-cell subsets, and cyclophosphamide (CY)-resistant precursors were enumerated at a high frequency by the modified VPA when the received in vitro antigen stimulation, and that the proliferative stage of these cells was critical for the development of V-PFC.  相似文献   
992.
What is known and Objective: Miconazole is a strong inhibitor of CYP2C9, one of the main enzymes involved in the metabolism of warfarin. Concurrent use of the two drugs leads to potentially serious adverse effects. Although it is often assumed that use of the oral miconazole gel is acceptable with concomitant warfarin, because of the low bioavailability following buccal administration, drug–drug interactions have been reported following such use. We aimed to investigate case reports of such interactions and develop a pharmacokinetic model to model such interactions. Methods: The Medline database from 1966 to October 2010 was used for literature search. Case reports of the potentiation of the anticoagulant effects of warfarin, such as the elevation of prothrombin time (INR), by concomitant administration of warfarin and miconazole oral gel were collected. We quantitatively estimated the extent of inhibition of warfarin metabolism by orally administered miconazole gel and compared our findings with case reports. Results and Discussion: Metabolism of (S)‐warfarin is inhibited potently following administration of a standard dose (200–400 mg/day in Japan) of miconazole gel. This may lead to in an increase in the blood concentration of warfarin and lead to serious adverse effects. The literature reports of clinical interactions with concomitant use of those drugs show that other factors may amplify the effects of any increase in blood concentration. What is new and Conclusion: We summarize all reported, clinically significant, cases of drug interaction between miconazole oral gel and warfarin. Pharmacokinetic modelling shows that concomitant administration of warfarin and miconazole oral gel can lead to substantial increase in warfarin concentration. However, our PK/PD model fails to capture the dramatic increases seen in INR values, and hence bleeding complications, reported in the literature. Taken together, the evidence suggests that concomitant use of miconazole gel and warfarin should be avoided. Even over‐the‐counter products containing miconazole should be used with caution by patients receiving warfarin.  相似文献   
993.
Circadian timing largely modifies efficacy of many medicinal drugs. This viewpoint has been applied in the clinical medicine, known as chronotherapy. We think this viewpoint should also be introduced into toxicology as "chronotoxicology", however, information about the diurnal variation in toxicant sensitivity is still very scarce. We present here a clear and reproducible diurnal variation of cadmium (Cd)-induced mortality in mice. Male ICR mice kept under standard condition (12 hr light/dark cycle, lights on at 08:00) were injected with CdCl(2) (7.2 mg/kg, one shot) intraperitoneally at different time points in the day (zeitgeber time (ZT) 0, 4, 8, 12, 16 or 20). Survival number was determined at 14 days after injection. Interestingly, mice were sensitive to Cd acute toxicity at ZT8, while tolerant at mid-dark to early-light phase (ZT16, ZT20 and ZT0). Hepatic GSH level showed small daily fluctuation, lowest at ZT8 and highest at ZT20, and this fluctuation was similar to the diurnal variation of Cd sensitivity. In contrast, hepatic metallothionein (MT) level was not significant in these time points, although their level also showed small daily fluctuation. Our results indicated that Cd-induced mortality had clear diurnal variation, and suggested that the hepatic GSH level was one of the important factors for determination of this Cd-induced diurnal mortality.  相似文献   
994.
In the present case study, the patient was a 65-year-old man who suddenly developed purpuric and necrotic lesions with severe pain in his fingers and toes. Laboratory investigations revealed marked eosinophilia (77.9%), but there was no evidence to support a diagnosis of parasitic infections, allergic disease, neoplasm or connective tissue disorder. The histopathological findings did not show any distinct vasculitis, but there were obliterative changes of the arterioles. The digital gangrene gradually progressed and was unresponsive to corticosteroid therapy. The patient eventually underwent amputation of the distal phalanges. We applied allogeneic cultured dermal substitute (CDS) to the skin defect. The allogeneic CDS was prepared by culturing fibroblasts on a two-layered sponge of hyaluronic acid and atelo-collagen. This CDS is able to release a number of cytokines including VEGF. The present case had a good clinical result.  相似文献   
995.
Hemodialysis (HD) patients frequently have an elevated left ventricular mass index (LVMI). Currently, left ventricular (LV) hypertrophy and dysfunction are considered to be the strongest predictors of cardiovascular mortality in dialysis patients. The objectives of the present study are to investigate the factors associated with elevated LVMI and to discuss therapeutic implications for the treatment strategy for pre‐dialysis and HD patients. The correlation among biochemical values, physical specimens, and LVMI using echocardiography was prospectively analyzed in 30 non‐diabetic HD patients in the Juntendo University Hospital. Measurement of these parameters was performed at 0, 12, and 24 months after initiation of HD. Systolic blood pressure (SP), human atrial natriuretic peptide (hANP), and hemoglobin (Hb) levels were significantly correlated with LVMI. SBP, residual glomerular filtration rate (rGFR), and serum albumin levels were identified as independent risk factors for LVMI in multivariate regression analysis at initiation of HD. SBP, hANP, and Hb levels were identified as independent risk factors for LVMI in multivariate regression analysis after 24 months. SBP, rGFR, and serum albumin levels were predictive factors for LVMI at initiation of HD. SBP, hANP, and Hb levels were also predictive factors for LVMI after initiation of HD.  相似文献   
996.
Pancreatic endocrine tumors (PETs) rarely involve the main pancreatic duct. We report a case of malignant nonfunctioning pancreatic endocrine tumor (NFPET) with prevalent intraductal growth. A 47-year-old woman was referred to us after ultrasonography at a routine health check showed diffuse swelling of the pancreas. Preoperative imaging showed a solid mass in the tail of the pancreas and a bulging intraductal mass in the main pancreatic duct. We performed total pancreatectomy because the tumor occupied almost the entire lumen of the main pancreatic duct. Histological examination confirmed well-differentiated endocrine carcinoma. We review reported cases of the intraductal growth of NFPETs and discuss the pathogenesis of these unusual tumors.  相似文献   
997.
998.
In this prospective multicenter study, we investigated the changes in serum prostate-specific antigen (PSA) and testosterone levels after treatment with antiandrogen chlormadinone acetate (CMA) in patients with benign prostatic hyperplasia (BPH). The inclusion criteria for the patients were as follows : PSA value of C10 ng/ml, maximum urine flow rate of <15 ml/s, estimated prostate volume of B20 ml, International Prostate System Score (IPSS) of B8, and IPSS-quality of life (QOL) index of B2. Of the 115 patients who registered, 114 qualified for this study. The patients were treated with CMA (50 mg/day) for 16 weeks ; this was followed by a no-CMA phase of 32 weeks. When compared with the baseline PSA level, the levels at 8 and 16 weeks of treatment had decreased by 56.4% (95% confidence interval [CI], 51.1-1.2) and 57.6% (95% CI, 52.3-62.4), respectively. Similarly, when compared with the baseline testosterone level, the levels at 8 and 16 weeks of treatment had decreased by 90.1% (95% CI, 87.8-91.9) and 84.4% (95% CI, 80.7-87.4), respectively. After treatment discontinuation, the PSA levels gradually increased and returned to baseline in 32 weeks. However, the testosterone levels returned to baseline in only 8 weeks. Although patients over 80 years of age showed a gradual decrease in these levels when compared with younger patients, the changes in the levels of PSA and testosterone were not affected by age. Thus, in order to use antiandrogen agents including CMA for treating BPH, we need to determine the PSA value that converted it into double.  相似文献   
999.
A 64-year-old woman presented with advanced gastric cancer (signet ring cell carcinoma) and underwent total gastrectomy in 1996. Postoperative recovery was good, and she was monitored regularly on an outpatient basis. Abdominal computed tomography in 1999 revealed a soft tissue shadow ventral to the origin of the celiac artery. Careful monitoring was continued on an outpatient basis. The patient began to experience gluteal swelling and pain in April 2008. Symptoms rapidly exacerbated and the patient was hospitalized for further examination. Gluteal muscle biopsy revealed signet ring cell carcinoma and bilateral hydronephrosis. Gluteal recurrence of the original gastric cancer was suggested, and systemic chemotherapy consisting of S-1 at 100 mg/day (3 weeks on, 1 week off) and CDDP (day 8) was started. Following the 6th cycle of chemotherapy, gluteal symptoms disappeared and the patient was judged to have achieved clinical complete response (CR). No adverse events or image findings suggesting new recurrence have since been identified. The patient received a total CDDP dose of 585 mg and clinical CR has been maintained as of 14 years after total gastrectomy and 18 months after recurrence.  相似文献   
1000.
The incidence of gastric cancer is higher in men than women. Epidemiological studies suggest that female hormones reduce gastric cancer risk. We examined the effect of ovarian-dependent female hormones on Helicobacter pylori-induced gastric cancer in hypergastrinemic INS-GAS mice. Male and female sexually intact or ovariectomized (OVX) mice were inoculated with H.pylori SS1 or vehicle-only at 10 weeks of age, and tissues were evaluated at 16 or 28 weeks post-infection (WPI). A subset of OVX females were supplemented with 17beta-estradiol (E2), beginning at 16 WPI. Stomachs were evaluated by histopathology, Ki-67 proliferation index, H.pylori quantitative culture and quantitative polymerase chain reaction for messenger RNA expression of inducible nitric oxide synthase (iNOS) and inflammatory cytokines. Infected OVX females developed significantly more severe gastritis (P < 0.05) than infected intact females at both time points. E2 treatment in infected OVX females attenuated the severity of gastritis. Gastrointestinal intraepithelial neoplasia (GIN) developed in 42% of infected males and 10% of infected OVX females by 28 WPI, whereas infected intact females and E2-treated OVX females did not develop GIN. Infected OVX females showed significantly increased iNOS expression and epithelial cell proliferation when compared with intact, infected females. Likewise, interferon-gamma, tumor necrosis factor-alpha and interleukin-1beta (IL-1beta) expression in infected OVX females were significantly increased at 28 WPI when compared with intact counterparts. E2 treatment in infected OVX females significantly decreased IL-1beta expression, increased IL-10 expression and reduced epithelial cell proliferation. These results demonstrate a protective effect of E2 in H.pylori-induced gastric cancer in a mouse model.  相似文献   
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