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991.
Lakshmi V Kumar R Gupta P Varshney V Srivastava MN Dikshit M Murthy PK Misra-Bhattacharya S 《Parasitology research》2004,93(6):468-474
The antifilarial activity of the marine red alga Botryocladia leptopoda against rodent and human lymphatic filarial parasites is described. The animal filarial species included Litomosoides sigmodontis and Acanthocheilonema viteae maintained in cotton rats and Mastomys coucha, respectively, while a subperiodic strain of the human lymphatic filarial parasite Brugia malayi was maintained in M. coucha. The crude extract and its hexane fraction brought about a marked reduction in the peripheral microfilarial level in both of the rodent filarial parasites L. sigmodontis and A. viteae. The microfilaricidal effect began slowly from day 8 or 15 after initiation of treatment and increased with time with a very high efficacy at the end of the observation period against both rodent filariids. The microfilaricidal efficacy was, however, not as prominent in the case of B. malayi. The antifilarial activity, which occurred in the hexane fraction, exerted action at a much lower dose. The product killed a significant proportion of A. viteae and L. sigmodontis adult parasites. In the case of B. malayi, although the macrofilaricidal efficacy was much less than that of the rodent parasites, it (hexane fraction) caused sterilization of a significant proportion of the surviving female parasites. The present findings indicate the possibility of developing an adulticidal and female sterilizing agent against filarial parasites from a marine red alga. 相似文献
992.
993.
994.
A high resolution computer model for sound propagation in the human thorax based on the Visible Human data set 总被引:1,自引:0,他引:1
Narasimhan C Ward R Kruse KL Guddati M Mahinthakumar G 《Computers in biology and medicine》2004,34(2):177-192
A parallel supercomputer model based on realistic tissue data is developed for sound propagation in the human thorax and the sound propagation behavior is analyzed under various conditions using artificial sound sources. The model uses the Visible Human male data set for a realistic representation of the human thorax. The results were analyzed in time and frequency domains. The analysis suggests that lower frequencies of around 100 Hz are more effectively transmitted through the thorax and that the spatial confinement of sound waves within the thorax results in a resonance effect at around 1500 Hz. The results confirm previous studies that show the size of the thorax plays a significant role in the type of sound generated at the chest wall. 相似文献
995.
Two novel and simple methods have been developed for detecting monoclonal antibodies (MAbs) with identical epitope specificities from a large population of MAbs against human chorionic gonadotropin (hCG). The first method was based on the observation that following radioiodination many molecules of an antigen are altered in such a manner that they cannot be recognized by MAbs. The proportion of radiolabelled antigen (Bmax) able to bind to a MAb was characteristic of that MAb and MAbs having identical specificities showed identical Bmax values. Using this principle it was possible to identify MAbs having identical epitope specificities within a large population of MAbs against hCG. In the second method one test MAb was immobilized on a plastic surface through an immunochemical bridge. This MAb was then incubated with 125I-hCG previously complexed with a second MAb. Such a complex could bind to the solid phase MAb only if the two MAbs were not identical. The results obtained with both methods were concordant. With such methods it is possible to identify MAbs with identical epitope specificities immediately after the initial screening of the fusion. These methods do not require subcloning, ascites production, or the purification and iodination of large number of MAbs. 相似文献
996.
U K Luthra P Bhatnagar D K Das B K Sharma V Kashyap I U Khan V Singh N S Murthy 《Annales de biologie clinique》1989,47(5):283-286
43, patients, subjected to cervical cytology, colposcopy and colposcopic directed biopsy, were found to have lesions suggestive of human Papillomavirus (HPV) infection by one or more parameters. Immunohistochemical staining for HPV antigen yielded positive results in 23 (53.5 p. cent) cases. Amongst 30 cases with HPV lesions both in cytology and histopathology, 19 (63.3 p. cent) were positive for the HPV antigen. This was significantly higher as compared to the groups where HPV lesion was observed in cytology or histology alone (p = 0.05). The rate of positivity was the highest (81.3 p. cent) in a group of 16 patients having low grade dysplasia (mild to moderate) and both cytology and histologic evidence of koilocytotic changes. Presence or absence of HPV lesion by colposcopic examination in these 43 cases did not make any significant difference in rate of antigen positivity. 相似文献
997.
Naoko Kobayashi R James Barnard Susanne M Henning David Elashoff Srinivasa T Reddy Pinchas Cohen Pak Leung Jenny Hong-Gonzalez Stephen J Freedland Jonathan Said Dorina Gui Navindra P Seeram Laura M Popoviciu Dilprit Bagga David Heber John A Glaspy William J Aronson 《Clinical cancer research》2006,12(15):4662-4670
PURPOSE: To determine whether altering the dietary content of omega-6 (n-6) and omega-3 (n-3) polyunsaturated fatty acids affects the growth of androgen-sensitive prostate cancer xenografts, tumor membrane fatty acid composition, and tumor cyclooxygenase-2 and prostaglandin E(2) (PGE(2)) levels. EXPERIMENTAL DESIGN: Individually caged male severe combined immunodeficiency mice were fed isocaloric 20% kcal fat diets with the fat derived either primarily from n-6 fatty acids (n-6 group) or with the fat consisting of n-6 and n-3 fatty acids in a ratio of 1:1 (n-3 group), and injected s.c. with Los Angeles Prostate Cancer 4 (LAPC-4) cells. Tumor volumes and mouse weights were measured weekly, caloric intake was measured 3 days per week, and tumors and serum were harvested at 8 weeks postinjection. RESULTS: Tumor growth rates, final tumor volumes, and serum prostate-specific antigen levels were reduced in the n-3 group relative to the n-6 group. The n-3 group tumors had decreased proliferation (Ki67 staining) and increased apoptosis (terminal nucleotidyl transferase-mediated nick end labeling staining). In vitro proliferation of LAPC-4 cells in medium containing n-3 group serum was reduced by 22% relative to LAPC-4 cells cultured in medium containing serum from the n-6 group. The n-6/n-3 fatty acid ratios in serum and tumor membranes were lower in the n-3 group relative to the n-6 group. In addition, n-3 group tumors had decreased cyclooxygenase-2 protein and mRNA levels, an 83% reduction in PGE(2) levels, and decreased vascular endothelial growth factor expression. CONCLUSION: These results provide a sound basis for clinical trials evaluating the effect of dietary n-3 fatty acids from fish oil on tumor PGE(2) and membrane fatty acid composition, and serum and tumor biomarkers of progression in men with prostate cancer. 相似文献
998.
Is there a simpler method for predicting lower pole stone clearance after shockwave lithotripsy than measuring infundibulopelvic angle? 总被引:2,自引:0,他引:2
Tuckey J Devasia A Murthy L Ramsden P Thomas D 《Journal of endourology / Endourological Society》2000,14(6):475-478
BACKGROUND AND PURPOSE: Several anatomic factors influence the clearance of lower pole stones treated with shockwave lithotripsy (SWL). One of these is the infundibulopelvic angle, but its measurement is complex. METHODS: We proposed a more simple measure of caliceal dependence, the caliceal pelvic height (CPH), which we defined as the distance between a horizontal line from the lowermost point of the calix containing the stone to the highest point of the lower lip of the renal pelvis. RESULTS: In 62 patients who had SWL for solitary lower pole stones, a CPH < 15 mm was associated with a stone clearance rate of 92%, whereas with a CPH > or = 15 mm, the clearance rate was only 52% (p < 0.05). A majority (74%) of the patients with an infundibular width of > or = 5 mm were rendered stone free compared with 40% of those with a width of < 5 mm (p < 0.05). CONCLUSION: Measurement of the CPH, in conjunction with other anatomic factors, may more accurately predict the outcome of SWL in patients with lower pole stones. 相似文献
999.
1000.
Srinivasa Prasad Sanjay Gupta Tufail Patankar Atul Goel 《Journal of Medical Imaging and Radiation Oncology》1999,43(4):529-531
Intracranial cystic neurogenic tumours constitute an uncommon subset of tumours with a distinct clinico-biological behaviour. The presence of fluid–fluid levels within the tumours, although rare, confirms the cystic nature of the neoplasms. Barring the acoustic schwannomas, cystic cranial nerve schwannomas are exceptionally uncommon. Imaging findings of fluid–fluid levels in two non-acoustic cranial nerve schwannomas are described; one was a cystic trigeminal schwannoma and the other was a glossopharyngeal nerve schwannoma. The causes of the fluid–fluid level and its implications are analysed. 相似文献