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21.
HLA-D/DR (Ia) glycoproteins were identified in human breast carcinoma and normal mammary gland cells by means of an anti-Ia monoclonal antibody. Two techniques were used: (1) immunoperoxidase staining performed on histological sections and (2) Ia glycoproteins were isolated as follows: firstly by radioactive labelling of isolated cells, then by filtration on Sephadex G25, followed by Lens culinaris chromatography, and immune complex formation and then elution on protein A-Sepharose. Lastly, the immune complex was studied by chromatofocusing. Both techniques revealed that Ia expression was found in carcinoma cells, but not in normal cells.  相似文献   
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A pilot study was designed to examine whether the outcome of embryo transfer in women with a hydrosalpinx might be improved by surgical drainage of the hydrosalpinx at the time of oocyte collection for in- vitro fertilization treatment. A comparative, controlled but retrospective analysis of the results was performed of all women with infective tubal damage aged <40 years old, who had ovulatory cycles, a normal uterus and a partner with normal spermatozoa. A standardized treatment regimen was used. A maximum of three embryos were transferred. Hydrosalpinx was defined by prior hysterosalpingography and/or laparoscopy with transcervical dye injection. A total of 237 embryo transfer cycles in women with hydrosalpinges (tubal distension not visible in 151, visible but not drained in 30 and drained in 56) were compared with 705 embryo transfer cycles in women with tubal disease but no hydrosalpinx. Results were analysed in the first three cycles but also separately in the first cycle to check for bias. Success rates were higher in the first cycle, but did not significantly influence overall differences. Implantation rates were significantly reduced overall in the hydrosalpinx group (8.0 versus 13.2% for controls; P < 0.001), being 8.3% (P < 0.01) in the subgroup without evident tubal distension and 7.5% (not significant) in the drained hydrosalpinx group. This study shows that tubal damage with distal occlusion is associated with a marked reduction in embryo implantation, even in the absence of obvious fluid distension. Surgical drainage of distended hydrosalpinges appears to offer no benefit.   相似文献   
24.
Low affinity FcR are a heterogeneous group of glycoproteinswhich exist in transmembrane (TM) as well as in soluble forms.Two membrane isoforms of the murine type II FcR, FcRilb1 andFc;Rilb2, have been described. They result from the translationof alternatively spliced premRNA, FcRilb2 lacking sequencesof the first intracytoplasmic domain (IC1). Soluble forms ofFcR (sFcR) have previously been shown to result from proteolysisof membrane receptors. We report here the identification, inmacrophages, of a mRNA derived from the FCRll gene by splicingexons encoding the TM and IC1 domains, i.e. corresponding toa TM-deleted FcRllb2 mRNA. A soluble protein possibly encodedby this mRNA was identified in macrophage supernatants. In accordancewith FcR nomenclature, we propose to name this new FcRll IsoformFcRllb3. It is the most abundant 8FcR present in serum, as comparedwith 8FcR resulting from cleavage of membrane FcR.  相似文献   
25.
The fructose analogue 2,5-anhydro-D-mannitol (2,5-AM) has been shown to act specifically in liver by decreasing liver ATP and by blocking glycogenolysis and gluconeogenesis. The present investigation was designed to determine the effects of the administration of 2,5-AM on pancreatic hormone responses during a situation of increased energy demand such as physical exercise, and by comparison to the resting response, to test the possibility that the hormonal effects of 2,5-AM during exercise may be dissociated from a decrease in blood glucose levels. Adrenodemedullated rats were injected intraportally with a dose of 200 mg/kg of 2,5-AM (50 mg/ml) or by an equivalent volume of saline (0.9% NaCl) before being submitted to a 30-min treadmill run (26 m/min, 0% grade). Administration of 2,5-AM at rest resulted in a significant (P < 0.05) decrease of plasma glucose and insulin levels and an increase in beta-hydroxybutyrate concentrations. During exercise, administration of 2,5-AM, as compared to resting values, resulted in a larger decrease in glucose, a similar decrease in insulin, and a much larger increase in glucagon, glucagon/insulin molar ratio, and beta-hydroxybutyrate concentrations. It is concluded that exercise amplifies some of the metabolic and hormonal effects of 2,5-AM, and that these effects cannot all be explained by the decrease in blood glucose levels.  相似文献   
26.
OBJECTIVE: To report a family with X-linked Charcot-Marie-Tooth disease (CMTX) with proven connexin 32 (Cx32) mutation associated with deafness. METHODS: Twelve members of a CMTX family were examined clinically. Electromyography and sensory and motor conduction studies were performed in three men, two women, and a 7-year-old boy. Audiometric testing was carried out in the three men, one woman, and an 8-year-old girl. Molecular genetic analysis was performed in six men and five women. RESULTS: The three men and the 7-year-old boy had the usual sensorimotor deficit and pronounced reduction of motor nerve conduction velocity. A 15-year-old boy was asymptomatic and had only areflexia. The women had impairment of vibratory sensation and slight slowing of nerve conduction velocities. Sensorineural deafness was observed in the three men and in an 8-year-old girl without any motor or sensory deficit. Molecular genetic analysis revealed a new missense mutation located in codon 142 of the Cx32 gene leading to the substitution of an arginine by a glutamine. CONCLUSION: CMTX due to Cx32 mutations often shows interfamilial and intrafamilial phenotypic variation, which is also the hallmark of this family. The sensorineural deafness observed in this family suggests that Cx32 could play an important role in the auditory pathway.  相似文献   
27.
The selectin family of cell-adhesion molecules contributes to the interactions of leukocytes and platelets at the site of vascular injury. Such interactions enhance inflammatory reactions and thrombus formation during the arterial response to injury. In this study, we investigated the effects of a selectin inhibitor (Fucoidan) on platelet and neutrophil interactions after arterial injury produced by angioplasty in pigs. [51Cr]-platelet deposition and [111In]-neutrophil adhesion were quantified on intact, mildly, and deeply injured carotid arterial segments, produced by balloon dilation in control (saline, n = 7) and Fucoidan-treated (i.v.; 1 mg/kg, n = 6; 5 mg/kg, n = 5) pigs. In the control group, platelet deposition (x10(6)/cm2) was influenced by the severity of injury and increased significantly (p < 0.05) from 0.06+/-0.06 on intact endothelium to 3.8+/-0.6 and 33.6+/-4.9 on mildly and deeply injured segments, respectively. Fucoidan, 1 mg/kg, had no significant effect, although doses of 5 mg/kg reduced platelet deposition by 73% on deeply injured segments. The level of neutrophil adhesion (x10(3)/cm2) was also influenced by the severity of injury: it increased in the control group from 8.8+/-2.5 on intact endothelium to 226.6+/-45.5 and 397.4+/-61.3 on mildly and deeply injured arterial segments, respectively (p < 0.05). Again, 1 mg/kg Fucoidan had no effect, although doses of 5 mg/kg reduced neutrophil adhesion by 92% and by 84% on mildly and deeply injured segments, respectively. The effects of Fucoidan were associated with a 51% decrease in the vasoconstrictive response at the site of arterial injury. However, Fucoidan had no significant effect on either platelet aggregation or activated clotting time (ACT). In the in vitro perfusion experiments, Fucoidan inhibited both isolated platelet, and neutrophil, adhesion to damaged arterial surfaces. This inhibition was more pronounced in experiments using mixed cell preparations, indicating that Fucoidan interferes with platelet and neutrophil interactions. These results highlight the importance of selectins in the acute physiopathologic reactions related to platelet-neutrophil interactions after arterial injury.  相似文献   
28.
The classification of hypertrophic cardiomyopathies remains a thorny nosological problem. Within this extensive diagnostic group, it is felt that the very special sub-group of "Japanese" apical hypertrophic forms must be subject to the strictest possible criteria in order to avoid improper use. The case reported here of biventricular apical hypertrophic cardiomyopathy in a 60-year-old woman with a family history of HCM, in whom the clinical, ECG and above all angiographic features were typically those of AHCM but where the existence of an intraventricular gradient was found during challenge manoeuvres emphasises this classification problem. Pseudo-AHCM in a context of OCM or pseudo-OCM in a context of AHCM? The discussion is not merely of nosological interest in view of the recently documented clear prognostic differences between these two conditions. Main series from the literature are reviewed.  相似文献   
29.
Acute respiratory failure and infectious pneumonia are the major causes of death during induction chemotherapy of acute leukemia. However, the causes, incidence and prognostic value of all respiratory events (REs) occurring in this context have never been assessed prospectively. We recruited 65 consecutive patients with newly diagnosed acute leukemia into a 1-year prospective study (December 2000-November 2001) to evaluate the incidence and prognostic value of these events. REs were frequent: 38 were recorded in 30 patients. There was a significant relationship between REs and pre-existing respiratory disease and/or smoking. REs were caused by infection in 34% of cases, by an established cause other than infection in 42% and had an undetermined cause in 24%. Poor early outcome (death within 45 days of starting induction chemotherapy) in patients experiencing an RE was independently associated with a >25/min respiratory rate (P=0.003) and the nonachievement of complete remission (CR) (P<0.0001). Predictors of overall survival in the entire patient population were the absence of CR (P<0.0001), REs (P=0.02) and a > or =2 performance status (P=0.03). In conclusion, REs are frequent during induction chemotherapy of acute leukemia and represent an independent prognostic factor of poor outcome, regardless of their cause.  相似文献   
30.
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