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51.
HIV‐related benign esophageal strictures have been reported secondary to idiopathic esophageal ulceration, cytomegalovirus (CMV) esophagitis, herpetic esophagitis, and increased sensitivity to radiation therapy. Despite extensive and deep nature of CMV ulceration, stricture formation is uncommon. There have been anecdotal reports of esophageal strictures secondary to CMV infection in HIV patients. Esophageal stricture has been reported during active CMV ulceration as well as subsequent to successful treatment. Esophageal strictures secondary to CMV have also been reported without prior ulceration. We report a patient with CMV esophagitis presenting with ulceration and stricture who developed total obliteration of esophageal lumen following treatment with gancyclovir.  相似文献   
52.
Inhibin from human seminal plasma is structurally identical to sperm coating antigen. Using the flow cytometric technique it has been demonstrated that there is a positive correlation between initial motility of sperm and the amount of inhibin coated on the spermatozoal surface.  相似文献   
53.
The possible role of inhibin in the etiology of polycystic ovarian syndrome (PCO) was studied. In rats PCO was induced by thiouracil and human chorionic gonadotropin (hCG). These animals were grouped under different treatment schedules: inhibin; antibodies to inhibin; ovine follicle stimulating hormone (FSH). In rats treated with antibodies to inhibin, there was a decrease in ovarian weight concomitant with specific increase in serum FSH levels. No changes in serum luteinizing hormone (LH) and prolactin levels were observed. However, testosterone levels were significantly decreased. Histological examination of the ovaries showed a marked arrest in the cyst formation with new growing follicles. In animals treated with inhibin, testosterone levels increased without any accompanying changes in ovarian weight. The circulating levels of prolactin and LH were unaffected. A decrease in serum FSH levels was accompanied by an increase in the number of cysts. The study corroborates the hypothesis that inhibin is involved in the development of PCO syndrome. Hence, an antagonist to inhibin may prove useful for the treatment of women with this condition.  相似文献   
54.
Neonatal screening in India poses more organisational and socio-economic rather than medical challenges. Based on the pilot study of 450 cord sera, the plan for screening considered cord TSH<30 μU/ml as normal, 30 to 80 as borderline with recall by letters and >80 as indicative of hypothyroid state, with recall by home visits. Of the 17,240 live births only 12,407 cord sera were collected. Envisaging follow-up difficulties, T4 was assayed in cord sera when TSH was>30 μ U/ml. 2·81% (350) babies needed recall. Only 30% of 302 (2·43%) babies with cord TSG 30 to 80 responded, to recall letters and were normal; availability of both cord TSH and T4 helped in excluding hypothyroidism in majority of non-respondents. Forty-eight (0·38%) newborns had TSH>90 μU/ml; 80% of this group and 100% with TSH> 100 μU/ml were traced by home visits. Hypothyroidism was confirmed in 5/48, biochemically and by thyroid scan. All five hypothyroids had cord TSH>300 μU/ml. The incidence in this nonendemic region of India was 1∶2481. Thus false elevation of cord TSH 30 to 300 μU/ml was noted in 0·34% with a chance of detecting a hypothyroid 1 in 10 when TSH>80 μU/ml. Screening strategies in a developing country must ensure meticulous clerical assistance, co-operation and education of nurses and parents, precise and cost effective technics and facilities for continued surveilance of detected hypothyroids.  相似文献   
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56.
Crystal structure of neotame anhydrate polymorph G   总被引:1,自引:0,他引:1  
Purpose. To determine the crystal structure of the neotame anhydrate polymorph G and to evaluate X-ray powder diffractometry (XRPD) with molecular modeling as an alternative method for determining the crystal structure of this conformationally flexible dipeptide. Methods. The crystal structure of polymorph G was determined by single crystal X-ray crystallography (SCXRD) and also from the X-ray powder diffraction (XRPD) pattern using molecular modeling (Cerius2 , Powder Solve module). Results. From SCXRD, polymorph G crystals are orthorhombic with space group of P212121 with Z = 4, unit cell constants: a = 5.5999(4), b = 11.8921(8), c = 30.917(2) Å, and one neotame molecule per asymmetric unit. The XRPD pattern of polymorph G, analyzed by Cerius2 software, led to the same P212121 space group and almost identical unit cell dimensions. However, with 13 rigid bodies defined, Cerius2 gives a conformation of the neotame molecule, which is different from that determined by SCXRD. Conclusions. For neotame anhydrate polymorph G, the unit cell dimensions calculated from XRPD were almost identical to those determined by SCXRD. However, the crystal structure determined by XRPD closely resembled that determined by SCXRD, only when the correct conformation of the neotame molecule had been chosen before detailed analysis of the XRPD pattern.  相似文献   
57.
Approximately one third of new cases of epilepsy have their onset before age 20 years. Many children will enter adolescence with epilepsy or have an onset of seizures during adolescence. Adolescence is a time of dramatic change in growth, hormonal, psychologic, and social situations. Seizure frequency, teenage pregnancy, driving, and alcohol and drug use often become major issues during the adolescent years. Furthermore, adolescents often have difficulty accepting the chronicity of epilepsy and complying with medications, which can result in physical injury and perceived or real obstacles to employment, thereby contributing to low morale. Both pediatricians and neurologists should be aware of adolescent issues in epilepsy.  相似文献   
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59.
Topical steroids play an extremely important role in the treatment of various dermatologic conditions. Use of topical steroids must be approached with caution, however, as they can have serious side effects. We report a case of iatrogenic perianal ulcers caused by twice-daily application of Lotrisone (clotrimazole and betamethasone dipropionate) in the perianal region. High-potency topical steroids should be used sparingly and briefly in intertriginous areas.  相似文献   
60.
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