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971.
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973.
Vertical thickness of cutaneous and subcutaneous lesions cannot be assessed accurately by simple examination. To achieve this ultrasonography was performed preoperatively and ruler assessment postoperatively. These measurements were then compared and evaluated using the Wilcoxon test. The results were not statistically significant (p=0.6592, z=0.4410). Cutaneous and subcutaneous ultrasonography is a simple, quick, accurate method of assessing lesion thickness. Received: 29 April 1997 / Accepted: 7 July 1997  相似文献   
974.
The effect of temperature and pregnant mare's serum gonadotropin (PMSG) was observed on the testes of Uromastix hardwicki at a time of the year (November) when the seminiferous epithelium contained abundant proliferating spermatogonia and some primary spermatocytes. This recrudescent state of the testes was maintained by keeping the animals at 20° for 10 days. But, in lizards kept at 35°, there was a marked decrease in the testis weight. The seminiferous tubules were lined mostly with Sertoli cells and a few resting types of spermatogonia. The interstitial cells were only slightly affected and there was no reduction in androgen concentrations in the testicular tissue or plasma, as measured by testosterone radioimmunoassay. At 20°, injections of 20 IU of PMSG daily for 10 days induced an increase in the number of primary spermatocytes and production of spermatids in certain regions of the tubules. In the PMSG-treated lizards kept at 35° the testes contained a single layer of resting spermatogonia placed along the basement membrane. Under these conditions PMSG failed to maintain the active state of the seminiferous epithelium. Unlike the germinal cells, the interstitial cells were markedly stimulated by PMSG at 20 or 35°. Testicular and plasma androgen levels were increased severalfold in gonadotropin-treated lizards. The elevation of androgen levels as a result of PMSG stimulation was higher in lizards kept at 35°. It is suggested that in Uromastix hardwicki, the germinal epithelium responds differentially to PMSG treatment at the two different temperatures and that the activity of the interstitial cells is not inhibited by hyperthermia.  相似文献   
975.
976.
A series of 22 benzimidazoles, having several substituents on the azole and benzene nuclei, were prepared and evaluated in vitro for antimicrobial activity. At first 2-chloro or 2-chloromethyl-5(6)-substituted-1H-benzimidazoles were synthesized, which were then substituted at C-2 with several piperazine or piperidine derivatives. The antibacterial activity of these compounds against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa, and the antifungal activity against Candida albicans, Candida stellatoidea, Candida parapsilosis, and Candida pseudotropicalis were determined as the MIC values. Since compound 12 exhibits good activity, in order to clarify the effect of substituents at C-1 on the activity, benzimidazole derivatives having ethyl, allyl, benzyl, and p-fluorobenzyl substituents at C-1 were prepared, and slightly increased activity was seen.  相似文献   
977.
Extra-skeletal Ewing's sarcoma (EES) is an uncommon malignancy, especially in the head and neck region that may arise in various extra-osseous tissues. We report a 22-year-old male with an EES of the submandibular gland, which to the best of our knowledge, has not been described previously. The patient who underwent combined treatment with surgical resection and chemo-irradiation was disease free for 22 months but succumbed to multi-organ metastases 14 months later. This case highlights the combined diagnostic role of immunohistochemical, cytogenetic and radiological evaluation of EES. EES is an aggressive cancer that requires multidisciplinary management with wide surgical excision and adjunctive chemo-irradiation for the best outcome.  相似文献   
978.
OBJECTIVES: We used dual energy x-ray absorptiometry (DEXA) and periapical radiography to assess bone density differences after conventional and bone-condensing dental implant techniques. STUDY DESIGN: Single-tooth dental implants were placed by both conventional and bone-condensing techniques in 14 patients with bilateral missing teeth. Dual energy x-ray absorptiometry was used to calculate bone mineral density (BMD) and bone mineral content (BMC) before and 6 and 12 months after implant placement. Furthermore, photodensitometry of periapical radiographs was also assessed. RESULTS: The success rate was 92.9% for the conventional technique and 71.5% for the bone-condensing technique. The BMD was observed to be significantly higher 6 and 12 months after implant placement. The BMC and photodensitometry were significantly increased 6 months after implant placement but showed no further after 12 months. CONCLUSIONS: There were no significant differences in BMD, BMC, and photodensitometry between the two implant placement techniques. However, success rate of the conventional technique was greater than the bone-condensing technique, which may be the result of trabecular fracture associated with the bone-condensing.  相似文献   
979.
BACKGROUND/AIMS: A significant association between variations in amino acid sequences resides between 2209-2248 nucleotides of HCV non-structural 5A (NS5A) gene, and response to interferon treatment has been proposed. The aim of this study was to determine whether the amino acid sequence changes in ISDR could be correlated to response to alpha interferon treatment in Turkish patients infected with HCV genotypes 1b and 1a. METHODS: Thirty-nine patients with chronic C virus infection (35 and 4 patients with genotype 1b and 1a, respectively), receiving 3x3-5 MU of interferon a-2b for six months were included in the study. Following PCR amplification of the region from pre-treatment serum samples, the products were directly sequenced. The amino acid sequence of NS5A was compared with the published sequence for HCV-J (AA 2209-2248). Mutant type was defined as three or more amino acid mutations, and intermediate type as 1-3 amino acids in this region. Otherwise, they were defined as the wild type (no amino acid mutations). HCV RNA serum viremia levels were analyzed by branched DNA assay. RESULTS: Eighteen patients were responders (R; 46%), whereas 21 patients were non-responders (NR; 54%). Amino acid changes in both R and NR groups did not show significant difference. Intermediate or wild type strains were detected in both groups. CONCLUSIONS: In this study, we could not determine a significant association between number of amino acid changes in NS5A2209-2248 and response to interferon treatment. In the majority of the patients, it seems that amino acid sequences in this region are well conserved.  相似文献   
980.
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