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1. The aim of this study was to assess the role of endothelial cells in the modulation of vasocontractile responses to endothelin-1 (ET-1) of human placental vasculature. 2. Isolated stem villi small arteries (diameter = 170-250 microns) were obtained from healthy parturients who underwent caesarean surgery during the 39th week of pregnancy for cephalo-pelvic disproportion. Isometric tension was measured in vascular rings mounted in a myograph system and challenged with ET-1 (10(-12) to 10(-6) M). 3. The vasocontractile response to ET-1 was significantly (P < 0.001) increased in endothelial-denuded (active tension = 1156 +/- 214 mN mm-1) as compared with endothelial-preserved vascular rings (active tension = 458 +/- 48 mN mm-1). This difference was significantly (P < 0.05) but only partly abolished by the NO synthase inhibitor N omega-nitro-L-arginine (L-NOARG, 10(-4) M). 4. In endothelial-preserved rings submaximally precontracted with 5-hydroxytryptamine (10(-6) M), ET-1 (10(-12) to 10(-9) M) induced dose-dependent relaxation (maximum relaxation = 70 +/- 7%) at 10(-9) M, which was followed, at higher doses (10(-8) to 10(-6) M), by a contraction. In contrast, no relaxation was seen in endothelial-denuded rings. The relaxation in rings with endothelium was significantly (P < 0.001) reduced by L-NOARG (10(-4) M. Moreover, it was totally abolished by combined pretreatment with L-NOARG (10(-4) M) and the sulphonylurea glibenclamide (10(-5) M).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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We describe 2 unrelated Bedouin girls who met the criteria for the diagnosis of Kenny-Caffey syndrome. The girls had some unusual features--microcephaly and psychomotor retardation--that distinguish the Kenny-Caffey syndrome profile in Arab children from the classical Kenny-Caffey syndrome phenotype characterized by macrocephaly and normal intelligence. The 2 girls did not harbor the 22q11 microdeletion (the hallmark of the DiGeorge cluster of diseases) that we previously reported in another Bedouin family with the Kenny-Caffey syndrome (Sabry et al. J Med Genet 1998: 35(1): 31-36). This indicates considerable genetic heterogeneity for this syndrome. We also review previously reported 44 Arab/Bedouin patients with the same profile of hypoparathyroidism, short stature, seizures, mental retardation and microcephaly. Our results suggest that these patients represent an Arab variant of Kenny-Caffey syndrome with characteristic microcephaly and psychomotor retardation. We suggest that all patients with Kenny-Caffey syndrome should be investigated for the 22q11 microdeletion. Other possible genetic causes for the Kenny-Caffey syndrome or its Arab variant include chromosome 10p abnormalities.  相似文献   
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The internal architecture of the talus has not previously been well described even though the morphological anatomy and the blood supply have been studied extensively. This study describes the internal architecture of the talus regarding its trabecular orientation, using high-resolution x-ray images of 13 dry tali and thick sections in the coronal, sagittal, and axial planes. The trabecular arrays and their relationship to talar fractures are described. The trabecular content of the neck of the talus is less than that of the head or the body. The direction of the trabecula in the neck is different from the orientation of the talar body trabeculae.  相似文献   
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Three serological tests: Immunodiffusion (ID), Counterimmunoelectrophoresis (CIEP) and Enzyme-linked immunosorbent assay (ELISA) were used to study the role of crude adult worm antigen (CAWA) of Toxocara canis and each of its purified fractions in the serodiagnosis of human toxocariasis. Sensitivities of the three tests were lower in the ocular than in the visceral group, using different antigens. Purified fraction 1 showed more sensitive and specific reactions in the three tests, compared to CAWA or purified fraction 2 (P-F2) antigen. The other purified fractions (P-F3, P-F4 and P-F5) gave no positive reactions in any of the three tests. Using P-F1 antigen, ELISA was the most sensitive technique for diagnosis of both visceral and ocular toxocariasis followed by CIEP and then ID and the difference was statistically significant. However, CIEP was the most specific test followed by ELISA and lastly ID test. The ELISA test using Excretory-Secretory (E-S) larval antigen of Toxocara canis was less sensitive than the ELISA test using P-F1, although it was 100% specific. Thus, ELISA test using P-F1 is the test of choice for diagnosis of human toxocariasis, but when the specificity of a reaction is in doubt, CIEP test using the same antigen can be of value.  相似文献   
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The charts and radiographs of 118 patients with 126 intraarticular fractures of the calcaneus were reviewed retrospectively. Eleven of 126 (8.7%) calcaneal fractures had injuries consisting of intraarticular calcaneal fracture, lateral subluxation or dislocation of the posterior facet, fracture extension into the calcaneocuboid joint, peroneal tendon subluxation, subluxation of the talus in the ankle mortise, and complete disruption of the anterior talofibular and calcaneal fibular ligaments or fracture of the lateral malleolus. There were six women and five men. The average age was 40 years (range, 17-65 years). The mechanism of injury was a motor vehicle accident in eight and a fall from a height in three. According to the classification of Sanders et al eight fractures were Type II, one was Type III, and two were Type IV. Followup at an average of 26 months (range, 14-38 months) showed that eight of 11 patients (72.7%) had either good or excellent results. When lateral subluxation of the posterior facet of the calcaneus is identified with a preoperative computed tomography scan, operative management is indicated, and the surgeon should search for associated injuries that should be addressed at the time of surgery.  相似文献   
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Background and study aimsBleeding internal haemorrhoids are common and used to be treated surgically with too many complications. Endoscopic therapy is trying to take the lead. Sclerotherapy and rubber band ligation are the candidates to replace surgical therapy especially in patients with liver cirrhosis. The aim of this study was to compare endoscopic injection sclerotherapy (EIS) to endoscopic rubber band ligation (EBL) regarding effectiveness and complications in the treatment of bleeding internal haemorrhoids in Egyptian patients with liver cirrhosis.Patients and methodsOne hundred and twenty adult patients with liver cirrhosis and bleeding internal haemorrhoids were randomised into two equal groups; the first treated with EBL using Saeed multiband ligator, and the second with EIS using either ethanolamine oleate 5% or N-butyl cyanoacrylate. All groups were matched as regards age, sex, Child score and pre-procedure Doppler values. Patients were followed up clinically and with abdominal ultrasound/Doppler for 6 months. Endoscopic and endosonography/Doppler was done before and one month after the procedure. Pre and post-procedure data were recorded and analysed.ResultsBoth techniques were highly effective in the control of bleeding from internal haemorrhoids with a low rebleeding [10% in the EBL group and 13.33% in the EIS group] and recurrence [20% in the EBL group 20% in the EIS group] rates. Child score had a positive correlation with rebleeding and recurrence in EIS group only.Pain score and need for analgesia were significantly higher while patient satisfaction was significantly lower in EIS compared to EBL [p < 0.05]. No significant difference between ethanolamine and cyanoacrylate subgroups was found [p > 0.05].ConclusionsBoth EBL and EIS were effective in the treatment of bleeding internal haemorrhoids in patients with liver cirrhosis. EBL had significantly less pain and higher patient satisfaction than EIS. EBL was also safer in patients with advanced cirrhosis.  相似文献   
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