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101.
The purpose of this study was to assess the influence of male, female and fetal cord sera, follicular fluid, and seminal plasma on human sperm-zona pellucida binding, using the hemizona assay. Steroids, gonadotrophins, growth hormone and prolactin concentrations in follicular fluid and sera were also analysed. The influence of follicular fluid (10 or 50%, v/v) and sera (10%) on sperm-zona pellucida binding was investigated by supplementing the sperm processing medium as well as the sperm-hemizona incubation medium. Different seminal plasma concentrations (1 or 10%) were added to the sperm-hemizona incubation medium. Supplementation with 10% day 3 donor serum was used as a control throughout experimentation. Although supplementation with male sera and fetal cord serum exerted a stimulatory effect (36 and 90% respectively; P < 0.029) on sperm-zona pellucida binding, hemizona indices obtained with addition of male sera, fetal cord serum and sera obtained from sub-fertile in-vitro fertilization (IVF) patients on day 12 of their menstrual cycle did not differ significantly (P > 0.05). Final progesterone concentrations in sperm-zona pellucida incubation media (10% follicular fluid supplementation), which ranged from 0.788 to 3.85 microg/ml, enhanced sperm binding to the zonae by >100% (P < 0.02). The utilization of follicular fluid (10%) as a natural physiological stimulus to enhance sperm-zona pellucida binding in an IVF setting is recommended. The presence of seminal plasma in the spermzona pellucida incubation media showed no beneficial effect on the binding ability of sperm, and can be viewed as an unfavourable substance in the proximity of the oocyte.   相似文献   
102.
A good result was achieved by treating ureteric perforation conservatively following ureteroscopy.  相似文献   
103.
The development of antibodies to factor VIII (inhibitors) in response to clotting-factor concentrates administration in hemophilia is common during the first few years of treatment but rare in multitransfused patients. We have investigated the possible association of a recently introduced factor VIII concentrate (Factor VIII CPS-P) in The Netherlands with the occurrence of inhibitors. To this effect, we conducted two studies. First, we performed a national multicenter study in which clinical information and inhibitor test results were obtained for 447 hemophilia A patients over the period 1988 through 1991. Secondly, for a baseline comparison we estimated the frequency of inhibitor development in a closely followed cohort of 144 patients, from 1984 through 1989. Before the introduction of Factor VIII CPS-P, the incidence of new inhibitors was 4.4/1,000 patient-years in the national study from March 1988 through May 1990, and 3.9/1,000 patient- years in the cohort followed from 1984 through 1989. These figures are similar to the incidence of new inhibitors that was found in a large cohort of patients in the United States followed in the 1970s. In the period that the new concentrate Factor VIII CPS-P was on the market, from June 1990 through November 1991, 11 clinically relevant inhibitors were detected, which yielded an incidence over this interval of 20.1/1,000 patient-years, a 4.5-fold increase compared with the previous interval (C195: 1.4 to 14.3). Nine of these 11 patients had in their lifetime received over 250 infusions with factor VIII preparations. whereas all of the inhibitors detected in the previous time interval, and all of the 24 inhibitor patients described in the US study, had received less than 250 infusions in their lifetime. All patients who developed inhibitors after June 1990 had been exposed to Factor VIII CPS-P, whereas only 75% of the patients who did not develop an inhibitor had been exposed to this product. In a prospective extension of the study, with a second inhibitor measurement after 3 months, we found that one additional inhibitor had developed during 52.5 patient-years of Factor VIII CPS-P use. In conclusion, there has been a sudden increase in the frequency of inhibitor patients, for a large part among multitransfused patients. It seems more than likely that this increase is associated with the introduction of a new factor VIII concentrate in The Netherlands.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
104.
105.
Matzinger  FR; Ho  CS; Yee  AC; Gray  RR 《Radiology》1988,167(2):431-434
Percutaneous transgastric placement of a drainage catheter under ultrasonographic and fluoroscopic guidance was performed in 12 patients with pancreatic pseudocysts. Complete resolution of the pseudocysts was obtained in eight patients, and the result was indeterminate in one patient due to early death from unrelated causes. Surgical intervention followed in two patients, one with a multiloculated pseudocyst that was incompletely drained and another with a pseudocyst that became infected following drainage. In one patient with metastatic tumor to the head of the pancreas the pseudocyst resolved initially, but a pseudocyst later recurred. There were no pancreaticocutaneous fistulas or other major complications. The transgastric route of pseudocyst drainage is safe and effective, and it offers a low risk of recurrence and fistula formation.  相似文献   
106.
The ultimate fate of T cells undergoing antigen-induced cell death in vivo remains controversial. Whereas apoptosis of CD4+ T cells driven by superantigen is readily detectable in lymphoid organs, CD8+ T cells have been reported to disappear from the lymphoid organs and accumulate in the liver where they undergo apoptosis. Using transgenic mice that produce large numbers of ovalbumin-specific CD8+ T cells (OT-I cells), we were able to investigate the events that follow soluble peptide administration in an independent CD8+ T cell system. Here we show that the OT-I cells undergo proliferation and apoptosis in situ in lymphoid organs in response to antigenic stimulation with no evidence for liver involvement. This is similar to the course of events found for CD4+ T cell activation and counters the view that the liver is a general site for CD8+ T cell clearance following antigen-specific activation.   相似文献   
107.
Thirty-four patients aged 4-67 yr (median 17) with acute lymphocytic leukemia (ALL) (18 patients) or acute nonlymphocytic leukemia (ANL) (16 patients) who failed to enter complete remission (CR) or relapsed on conventional chemotherapy were treated with cyclophosphamide (CY), 60 mg/kg/day for 2 days, 1000 rad total body irradiation, and a marrow transplant from a genotypically identical normal twin. Sixteen of the patients received additional chemotherapy within the week before CY. After the transplant, 23 patients received immunotherapy consisting of killed autologous leukemic cells and/or normal twin peripheral blood lymphocytes, 16 as part of a prospectively randomized study. One moribund patient died before engraftment. Nine patients (6 ALL, 3 ANL) continued to have detectable leukemic cells. Twenty-four patients (70%) achieved CR. One of them died of viral hepatitis at 1 mo and another of viral interstitial pneumonitis at 4 mo in CR. Fourteen patients (7 ALL, 7 ANL) relapsed 2-16 mo (median 4) after transplantation. However, 8 patients (24%) (3 ALL, 5 ANL) remain in CR without any maintenance chemotherapy at 29-103 mo (median 80) after the transplant. The end results were not signficantly influenced by the type of leukemia, the immediated pre-CY chemotherapy, or the immunotherapy. The results show that this approach, even when applied to endstage patients with acute leukemia in relapse, causes tolerable morbidity, rare nonleukemic deaths, and frequent remissions, some of which represent cures.  相似文献   
108.
The transfusion of blood may suppress the immune responses of patients with renal transplants and with malignant disorders. To study the in vitro suppressive effects of banked blood, 4 units of blood were stored in CPDA-1 and ADSOL at 4 degrees C for 14 days. Lymphocytes and plasma or ADSOL supernatants were harvested on Days 0, 4, 7, 10, and 14. Subpopulations of lymphocytes were enumerated by flow cytometry. Recalcified and heat-treated plasma and supernatants from the units of blood were added to mixed lymphocyte cultures (MLC) composed of cells from normal individuals. No significant changes were noted in the proportions of T or B cells from blood stored under these conditions. A 60 +/− 3 percent inhibition in the proliferative response was observed when plasma from CPDA-1 units was added to MLCs (p less than 0.02). Supernatants from ADSOL units demonstrated a 29 +/− 4 percent inhibition (p less than 0.10) of the proliferative response, and this inhibition of response was observed on all 14 days of the study. When appropriate concentrations of dextrose or adenine were added to other MLCs, adenine (at the concentration found in ADSOL) caused a significant inhibition of the proliferative response. This inhibition was not, however, as marked as that observed with recalcified, heat- treated plasma from CPDA-1 units. We conclude that adenine plus some additional factor(s) found in the liquid portion of stored blood inhibits the proliferative response of normal lymphocytes. It is possible that these factors contribute to the immune suppression observed in vivo in some patients who receive blood transfusions.  相似文献   
109.
Bicuspid aortic valve (BAV) disease remains the most common congenital cardiac disease and is associated with an increased risk of potentially fatal aortopathy including aortic aneurysm and dissection. Mutations in the NOTCH1 gene are one of only a few genetic anomalies identified in BAV disease; however evidence for defective NOTCH signaling, and its involvement in the characteristic histological changes of VSMC apoptosis and differentiation in ascending aortae of BAV patients is lacking. This review scrutinizes the evidence for the interactions of NOTCH signaling, cellular differentiation and apoptosis in the context of aortic VSMCs and provides focus for future research efforts in the diagnosis of BAV aortopathy and prevention of catastrophic complications through NOTCH signaling manipulation.  相似文献   
110.

Introduction

Fulvestrant shows dose-dependent biological activity. Greater estrogen-receptor (ER) blockade may feasibly be achieved by combining fulvestrant with anastrozole. This pre-surgical study compared fulvestrant plus anastrozole versus either agent alone in patients with ER-positive breast cancer.

Methods

In this double-blind, multicenter trial, 121 patients received fulvestrant 500 mg on Day 1 plus anastrozole 1 mg/day for 14 to 21 days (F + A); fulvestrant plus anastrozole placebo (F); or fulvestrant placebo plus anastrozole (A), 2 to 3 weeks before surgery. ER, progesterone-receptor (PgR) and Ki67 expression were determined from tumor biopsies before treatment and at surgery.

Results

A total of 103 paired samples were available (F, n = 35; F+A, n = 31; A, n = 37). All treatments significantly reduced mean ER expression from baseline (F: -41%, P = 0.0001; F + A: -39%, P = 0.0001; A: -13%, P = 0.0034). F and F + A led to greater reductions in ER versus A (both P = 0.0001); F + A did not lead to additional reductions versus F. PgR and Ki67 expression were significantly reduced with all treatments (means were -34% to -45%, and -75% to -85%, respectively; all P = 0.0001), with no differences between groups.

Conclusions

In this short-term study, all treatments reduced ER expression, although F and F + A showed greater reductions than A. No significant differences were detected between the treatment groups in terms of PgR and Ki67 expression. No additional reduction in tumor biomarkers with combination treatment was observed, suggesting that F + A is unlikely to have further clinical benefit over F alone.

Trial registration

Clinicaltrials.gov NCT00259090.  相似文献   
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