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Vascularization is a prominent event during corpus luteum formation, providing low density lipoproteins for steroid biosynthesis and enabling transport of secreted steroids. The process of vascularization is controlled by specific regulators. Vascular endothelial growth factor (VEGF), otherwise named vascular permeability factor (VPF), induces endothelial cell proliferation as well as angiogenesis in vivo and increases capillary permeability. Here we report the expression of VEGF/VPF mRNA by cultured human luteinized granulosa cells (GC) for at least 10 days. Without HCG VEGF/VPF expression declined after day 4 and by day 10 was reduced to approximately 30% of the value at day 4. However, after culture in the presence of 1 U/ml human chorionic gonadotrophin (HCG), expression of VEGF/VPF mRNA by GC was four times greater than control experiments by day 10, and increased 100% from day 4 to day 10. Simultaneously, HCG supplementation increased VEGF/VPF secretion by GC. Medium VEGF/VPF on day 3 was 13 pM without and 11 pM with HCG. Medium VEGF/VPF on day 10 was 6 pM without HCG and 29 pM with HCG. These results suggest that vascularization of the corpus luteum is induced by HCG-mediated effects of VEGF/VPF.   相似文献   
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The intermediate filament proteins nestin, vimentin, and desmin show a specific temporal expression pattern during the development of myofibers from myogenic precursor cells. Nestin and vimentin are actively expressed during early developmental stages to be later down-regulated, vimentin completely and nestin to minimal levels, whereas desmin expression begins later and is maintained in mature myofibers, in which desmin participates in maintaining structural integrity. In this study we have analyzed the expression levels and distribution pattern of nestin in intact and denervated muscle in rat and in human. Nestin immunoreactivity was specifically and focally localized in the sarcoplasm underneath neuromuscular junctions (NMJs) and in the vicinity of the myotendinous junctions (MTJs), ie, in regions associated with acetylcholine receptors (AChRs). This association prompted us to analyze nestin in neurogenically and myogenically denervated muscle. Immunoblot analysis disclosed a marked overall increase of accumulated nestin protein. Similar to the extrajunctional redistribution of AChRs in denervated myofibers, nestin immunoreactivity extended widely beyond the NMJ region. Re-innervation caused complete reversion of these changes. Our study demonstrates that the expression levels and distribution pattern of nestin are regulated by innervation, ie, signal transduction into myofibers.  相似文献   
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Lesions of the articular surfaces of the knee have been managed by various techniques over the last 50 years. Surgical management has involved: excising the damaged area, refashioning the underlying bone to produce a fibrous response, and introducing allograft, autograft and synthetic materials to encourage a repair matrix. The techniques and their pitfalls are reviewed and discussed, and suggestions made as to the direction of future studies for the repair of osteochondral lesions in the painful knee.  相似文献   
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Renal transplant (RT) is now a therapy of choice for end stage renal disease (ESRD). The Nephrology Unit, Asvini started functioning in Dec 90 and to date 1298 sittings of hemodialysis have been given to 45 patients. Of these, 35 were in ESRD and 11 patients underwent renal transplantation at this hospital during the period Jan 91 – Dec 93. One patient expired after 18 months of transplantation due to infection. Early experience in screening patients for RT, use of immunosuppression, management of rejection episodes and protocol are presented with special emphasis on its relevance to the Armed Forces.KEY WORDS: Transplantation, Renal Failure, Immunosuppression, Rejection  相似文献   
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OBJECTIVE: To compare the results of open and laparoscopic fundoplication. DESIGN: Nonrandomized controlled study with a 3-year follow-up. PATIENTS AND METHODS: Fifty-seven consecutive patients with erosive reflux esophagitis underwent laparoscopic (30 patients) or open (27 patients) fundoplication. INTERVENTIONS: Interview by an independent person. In addition, 52 patients (91%) underwent postoperative endoscopy, and 38 patients (67%) underwent esophageal 24-hour pH recording. RESULTS: Temporary dysphagia was reported by 20 patients (67%) after laparoscopic and by 11 (41%) after open fundoplication (P = .05). There were no differences between groups concerning incidence of persistent dysphagia (20% vs 18%, respectively) and mild to no reflux symptoms (97% vs 100%, respectively). In addition, bloating (50% vs 63%, respectively) and increased flatus (77% vs 78%, respectively) were equally common. Visual analog scale scores for dysphagia, bloating, and increased flatus were 0.6, 2.4, and 4.3, respectively, in the laparoscopic and 0.6, 3.5, and 3.4, respectively, in the open groups. Normal belching ability was reported by 12 patients (40%) after laparoscopic and by 20 (74%) after open fundoplication (P = .01). Visick grade 1 or 2 was reported by 21 patients (70%) after laparoscopic and by 24 (89%) after open fundoplication (P = .08). Defective fundic wrap was detected in 4 patients (13%) in the laparoscopic and in none in the open group. In addition, abnormal results of 24-hour pH recording were found in 4 patients (22%) after laparoscopic and in 2 (10.5%) after open fundoplication. CONCLUSION: From a functional point of view, both techniques were equally effective except concerning belching ability and temporary dysphagia.  相似文献   
10.
We present a series of 19 avulsions of the distal tendon of the biceps brachii muscle after a follow-up of 2 to 11 years. Ten patients with delayed diagnosis and treatment (3 weeks to 5 months) were compared with nine patients treated early (within 8 days after injury). Excellent or good results at follow-up were obtained in 9 of 10 patients in the delayed-treatment group and in all 9 patients in the early-treatment group. Nine of 10 patients in the delayed-treatment group and all patients in the early-treatment group had been able to return to their preinjury levels of activity. For reference, a meta-analysis of 147 cases reported previously was performed. Ninety percent of the patients treated with an anatomic reinsertion had excellent or good results after an average follow-up of 3 years, while similar results after 3 years were seen in 60% of the patients who had nonanatomic tendon reinsertion and in 14% of the patients who were treated nonoperatively. The delay of up to 3 years between injury and anatomic reinsertion had not compromised the result. From these data we concluded that anatomic reinsertion of the avulsed distal biceps tendon to the radius is the preferred treatment in acute as well as chronic injuries.  相似文献   
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