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11.
We conducted a study of the basal levels of gonadotropins in 38 patients with Turner's syndrome, 14 of whom were using hormone replacement therapy (HRT). The gonadotropin levels were compared with pubertal development and HRT. Seven patients had presented spontaneous menarche; five patients maintained their periods and normal gonadotropin levels, and two developed secondary amenorrhea and high gonadotropin levels. The majority of patients on HRT had high gonadotropin levels. Follicle stimulating hormone (FSH) levels were significantly lower (p = 0.001) in patients with breast development at stage 5, regardless of whether the patient had undergone a spontaneous or a hormonally induced puberty. We concluded that gonadotropin levels are normal in those patients with spontaneous periods, and are high in most patients on HRT; and that FSH levels are significantly lower in those patients with breasts at stage 5.  相似文献   
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INTRODUCTION: The biological activity of the natriuretic peptide (NP) system is dependent on the balance between NP tissue levels and the local expression of their receptors. In the kidney, the natriuretic peptide receptor type A (NPR-A) is the principal receptor mediating NP activity and is mainly expressed in the renal medulla. An increase in circulating NP levels is well documented in chronic renal failure (CRF); however, the renal expression of NPR-A has not been evaluated in this condition. METHODS: Wistar-Han rats were submitted to right nephrectomy plus ablation of both poles of the left kidney (3/4nx; n=27) or were sham operated (Sham; n=22) and followed for up to 26 weeks post surgery. Blood pressure measurements were performed weekly. Two, 10 and 26 weeks after surgery, renal sodium and creatinine excretion were evaluated and the kidneys removed for NPR-A mRNA quantification by real-time PCR. The results of mRNA quantification are expressed in arbitrary units (AU) set as the mean value of the Sham group (Sham=1 AU), after normalization for GAPDH (p<0.05). weeks after surgery) and in elevated fractional sodium excretion (+270%, 26 weeks after surgery). Although sodium intake was similar in 3/4nx and Sham rats, blood pressure was higher in 3/4nx rats and increased progressively throughout the study. This was accompanied by a marked decrease in NPR-A mRNA levels in the renal medulla from 3/4nx animals at 2, 10 and 26 weeks post surgery. Conclusion: In 3/4nx rats, the expression of NPR-A in the renal medulla of the remnant kidney is markedly reduced from 2 weeks up to 26 weeks post surgery. It is suggested that this may contribute to the progressive increase in blood pressure, as well as to the renal fibrosis observed in 3/4nx rats.  相似文献   
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The presence of vascular permeability factors in the extracellular products (ECP) of 10 strains of Renibacterium salmoninarum with different geographical origin and serological characteristics are reported. All the ECP produced haemorrhagic and/or oedematous zones at the injection site with a diameter ranging from 10-30 mm. However, the ECP samples did not display toxic effect in fish at the same dose as inoculated in rabbit (180-400 micrograms protein/0.1 ml). No differences were observed in the production of this dermatotoxic factor between the two antigenic groups found in this microorganism. Whereas heating (80 and 100 degrees C/15 min) the ECP samples resulted in a complete loss of their proteolytic activity, only a decrease (but not total inactivation) of the dermatotoxic effects was detected. Therefore, although proteases could be implicated in the permeability factor, they are not totally responsible for this activity.  相似文献   
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Inherited defects of the natural coagulation inhibitors predispose patients to thrombosis. These disorders have similar clinical presentations with a strong family history of thrombosis, episodes of recurrent venous thromboembolism, beginning in early adulthood. We report a case of upper gastrointestinal bleeding in a patient with portal hypertension due to portal-vein thrombosis secondary to hereditary protein C deficiency, an association that has seldom been reported.  相似文献   
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A new technique of choledochoenterostomy was devised to solve some of the problems of enterobiliary anastomosis with a normal calibre. The distal extremity of the common bile duct is completely surrounded by the bowel mucosa to a length of 3 cm after seromyectomy of a bowel wall rectangle of 4 × 1 cm. Experimental studies in rats and dogs demonstrated that this procedure prevents the risks of anastomotic disruption and functions like a mechanical unidirectional valve, which has great efficacy in stopping enterobiliary reflux. Studies in ten patients with obstructive jaundice with an extrahepatic biliary dilation less than 1.2 cm diameter submitted to this procedure Confirmed the experimental results. All patients were asymptomatic, without jaundice and with normalization of the liver enzymes after 2 months. The permeability of the valvular anastomosis studied by cholangiography, the HIDA 99mTc test and manometry was quite similar to other classical biliary-enteric anastomosis. In contrast, anti-reflux efficacy was only demonstrated in patients with a valvular anastomosis.  相似文献   
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From September 1984 to December 1989, 38 patients of pediatric age with localized bone sarcomas received intraoperative radiotherapy (IORT) as part of a multidisci plinary treatment program. The age ranged from 6 to 21 years. The tumor histologies were 22 osteosarcomas and 16 Ewing's sarcomas. Thirty-four had initial primary disease (90%) and 4 were treated for local recurrence (10%). IORT was used on 32 untreated patients and in 6 previously treated with external beam radiotherapy (EBR). The IORT field included the surgically exposed tumor bed area. Single radiation doses ranging from 10 to 20 Gy were delivered, using 6–20 MeV electron beams. The median follow-up time for the entire group is 25 months (2–65+ months). The projected 5-year disease-free and overall survival rates are 65% and 69%, respectively. One patient developed a local recurrence in each histological group: one chondroblastic osteosarcoma and one cervical Ewing's sarcoma. Six patients died from metastatic progression: 3 initially recurrent tumors and three primary disease cases. Severe neuropathy and soft tissue necrosis were seen in some patients as IORT related complications. IORT is a feasible technique to be integrated in multidisciplinary programs that may promote local control in pediatric and adolescent patients with bone sarcomas. Peripheral nerves are dose-limiting tissue structures for IORT.  相似文献   
19.
INTRODUCTION: In patients (pts) with atrial fibrillation (AF) of more than 48 hours' duration, electrical cardioversion (ECV) should only be performed after 3 weeks of effective anticoagulation. Transesophageal echocardiography (TEE) allows earlier ECV; however, despite exclusion of thrombi in the atrium and left atrial appendage (LAA), cases of thromboembolism related to ECV have been documented in AF. To define a low-risk group for cardioversion without previous anticoagulation, pts were selected for immediate ECV if no thrombi or dynamic spontaneous echo contrast (auto-contrast) were found after TEE and if LAA velocity was more than 0.25 m/sec. METHODS AND RESULTS: We performed TEE in 31 consecutive pts referred for ECV for AF of more than 48 hours' duration and without previous anticoagulation. After TEE the pts eligible for immediate ECV began anticoagulation with low molecular weight heparin (enoxaparin), subcutaneously in therapeutic doses, together with warfarin immediately before cardioversion. Enoxaparin was continued until an INR of over 2 was reached. Based on the TEE findings, the pts were divided in 2 groups: immediate ECV, group A, 20 pts with a mean age of 62 +/- 13 years, 6 female; and conventional therapy with warfarin before ECV, group B, 11 pts, mean age of 67 +/- 10 years (p < 0.05), 2 female. None of the pts in either group had mitral stenosis or previous episodes of thromboembolism. The mean transverse diameter of the left atrium in the 31 pts was 47 +/- 4.5 mm, without statistically significant differences between the 2 groups. Of the 11 pts in group B, 3 had a thrombus in the LAA, 6 dynamic spontaneous echo contrast and the remainder LAA velocities of less than 0.25 m/sec. ECV was achieved in all the pts, with no complications. Oral anticoagulation was maintained for at least a month. At one month, sinus rhythm was maintained in 75% of group A and 45% of group B (p < 0.01). CONCLUSION: In pts with AF of more than 48 hours' duration and no previous history of thromboembolism, the use of our exclusion criteria during TEE enabled stratification of a low-risk population for immediate ECV, which was accomplished effectively and safely in 2/3 of the pts. This strategy is associated with early symptomatic improvement, and may contribute to maintenance of sinus rhythm after one month, which was significantly better than in the pts who had prolonged therapy with warfarin before ECV, despite the differences found in age and left ventricular function.  相似文献   
20.
This study was designed to verify the safety and efficacy of botulinum toxin type A (BTX-A) used as a neuromuscular block on spastic masticatory musculature of children with cerebral palsy. Six patients who had spastic-tetraplegic cerebral-palsy, aged 5 to 20 years were selected. All patients had spasticity of the jaw muscles, bruxism, lower lip trauma, limited mouth opening, and difficulties in cleaning the oral cavity. The patients were sedated under general anesthesia, while the dentist injected the masseter and temporalis muscles bilaterally with 150 and 75 units of BTX-A each. Clinical examinations were conducted at 7, 14, 30, and 90 days after the initial appointment. We found statistically significant decreases in muscle spasticity and bruxism ( p = 0.002), improved inter-incisal opening ( p = 0.002), improved oral hygiene ( p = 0.031), and less lower lip trauma ( p = 0.060) after the neuromuscular blocking.  相似文献   
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