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In mouse, oral administration of the benzene extract of Hibiscus rosa-sinensis flowers at a dose level of 1 gm/kg body weight/day from day 5-8 of gestation led to termination of pregnancy in about 92% of the animals. The effect was associated with a significant fall in peripheral level of progesterone and increase in uterine acid phosphatase activity, as measured on day 10. The ovary exhibited signs of luteolysis, and the corpus luteal delta 5-3 beta -hydroxysteroid dehydrogenase activity decreased markedly. The interceptive effect of the extract was prevented completely by exogenous progesterone (1 mg/mouse/day) or chorionic gonadotropin (1 I.U./mouse/day) and partially (62.5%) by exogenous prolactin (500 micrograms/mouse/day). In unilaterally pregnant mouse having trauma-induced deciduomata in the sterile horn, the extract caused resorption of the fetuses, and regression of the deciduomata accompanied by reduction in weight of the ovaries. Luteolysis, may be due to interference with the luteotropic influence, and a consequent fall in plasma level of progesterone have been suggested as the plausible cause of termination of pregnancy.  相似文献   
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Drug resistance—arising from the misuse and overuse of antimicrobial agents—is becoming a major concern as new strains of resistant microorganisms are emerging and fewer new antimicrobial drugs are in development. This paper presents an idea of implementing a Real Time Web Based Information System to monitor changes in the antibiotic sensitivity of microorganisms, located at different areas and time periods based on data collected from accredited laboratories. This pattern can be mapped over geographical map of the area and can be interpreted by clinicians/policy makers. The authors demonstrate the use of such information system using cross sectional data obtained from a nasopharyngeal swab survey of 151 children affected with HIV. Such system can aid physicians to improve the choice of antibiotic to be administered using real time data.  相似文献   
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Background:

Management of femoral diaphyseal fractures in the age group of 6-16 years is controversial. There has been a resurgence worldwide for operative fixation.

Materials and Methods:

Twenty-two children (18 boys, 4 girls) aged 6-16 years with recent (> 3 days) femoral diaphyseal fractures (20 closed, 2 open) were stabilized with Titanium Elastic Nail (TEN). These fractures were in proximal third (n=3), middle third (n=15) and in the distal third (n=4) 17 patients underwent surgery within seven days of their injury. The results were evaluated using Flynn''s scoring criteria. Statistical analysis was done using Fischer''s exact test.

Results:

All 22 patients were available for evaluation after a mean of 26 months (14-36 months) of followup. Radiological union in all cases were achieved in a mean time of 8.7 weeks. Full weight bearing was possible in a mean time of 8.8 weeks. Mean duration of hospital stay was 9.8 days. The results were excellent in 13 patients (59.0%), successful in six (27.2%) and poor in three patients (13.6%). All patients had early return to school.

Conclusion:

Intramedullary fixation titanium elastic nailing is an effective treatment of diaphyseal fractures of the femur in properly selected patients of the 6-16 years age group.  相似文献   
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Defects involving the distal leg and foot are frequently encountered following various aetiological factors. Paucity of local tissue causes surgeons to resort to the retrograde peninsular flap, the cross leg flap or the free flap. With specific knowledge of perforators, the fasciocutaneous flap from the calf area can be transferred to the defect in a single stage based on skeletonised distal perforators. The surgical anatomy, flap planning and procedure have been detailed. Nineteen patients were treated during the period 1995 to 2005. The perforators were identified preoperatively by audio Doppler. The flaps were marked and dissected proximal to the defect skeletonising the distal perforators under loupe magnification and transferred to the defect in a single stage. The donor site was skin grafted. Out of 19 cases, 16 flaps healed uneventfully, one flap necrosed completely and in two cases there was marginal necrosis. The cases were followed up for 2-10 years with an average of 6 years. With detailed knowledge of perforators one can safely reconstruct distal moderate-size defects of the lower limb in a single stage, thus having the benefits of free tissue transfer without resorting to microsurgery. This technique has proved to be an advancement in the reconstructive repertoire allowing flaps of non conventional dimensions to be perfused by skeletonised perforators.  相似文献   
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Introduction The purpose of this study was to identify radiological predictors of early and late instability following conservative treatment of extra-articular distal radius fractures.Materials and methods An observational study design was employed using patient records and standardized radiological follow-up examinations as data sources. The database at a single institution was used to identify all patients with extra-articular distal radius fractures over the course of 1 year. A total of 71 patients with extra-articular distal radius fractures (50 dorsally displaced, 21 undisplaced) fulfilled the inclusion criteria. Patients were predominantly female (87%) with a pooled mean age of 64.9 years. All patients with displaced extra-articular distal radius fractures underwent closed reduction with subsequent cast immobilization. Undisplaced fractures were simply treated with cast immobilization. The primary outcomes were early (1 week) and late (6 weeks) instability of the fracture. Instability was defined as: (1) dorsal tilt >15°, (2) volar tilt >20°, (3) ulnar variance >4 mm, (4) radial inclination <10°.Results Degree of radial shortening and volar tilt were predictive of early instability (p<0.05), with dorsal comminution also approaching statistical significance (p=0.06). Radial inclination, age, radial shortening, and volar tilt were predictive of late failure (p<0.05). An unexpected result showed that one-third of undisplaced fractures went on to fail, most of which occurred in those patients over the age of 65 years.Conclusion An awareness of independent predictors of instability in extra-articular distal radius fractures is helpful in anticipating the final alignment outcome.  相似文献   
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