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Gastric teratoma is a very rare benign tumor. Fifty-three cases, only two of which were females, have previously been reported. This report concerns two cases of teratoma arising from stomach. One of them is the third female case described in the literature.  相似文献   
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Administration of caffeine (1,3,7-trimethylxanthine), a major component of coffee, to Swiss mice at doses of 80 or 100 mg/kg body weight 60 min prior to whole-body lethal dose of gamma-irradiation (7.5 Gy) resulted in the survival of 70 and 63% of animals, respectively, at the above doses in contrast to absolutely no survivors (LD-100/25 days) in the group exposed to radiation alone. Pre-treatment with a lower concentration of caffeine (50 mg/kg) did not confer any radioprotection. The protection exerted by caffeine (80 mg/kg), however, was reduced from 70 to 50% if administered 30 min prior to irradiation. The trend statistics reveal that a dose of 80 mg/kg administered 60 min before whole-body exposure to 7.5 Gy is optimal for maximal radioprotection. However, caffeine (80 mg/kg) administered within 3 min after irradiation offered no protection. While there is documentation in the literature that caffeine is an antioxidant and radioprotector against the oxic pathway of radiation damage in a wide range of cells and organisms, this is the first report demonstrating unequivocally its potent radioprotective action in terms of survival of lethally whole-body irradiated mice.  相似文献   
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Guineaworm control case study: planning a multi-strategy approach   总被引:2,自引:0,他引:2  
The planned global eradication of guineaworm (dracunculiasis) offers opportunities to learn about relatively complicated disease control situations. Unlike smallpox, which was eradicated over 10 years ago through immunization, the guineaworm problem has no one solution, but must rely on a variety of technologies to protect, treat or replace existing unsafe community water supplies which harbour the disease. Experiences in rural Nigeria have shown that a multi-strategy approach is necessary to account for differences in geographical settlement patterns, local culture and beliefs, geology of the area, economy of the villages and political clout of town leaders among the five major segments of the community. Through a self-help primary health care programme, residents of the Idere community were able to dig wells, produce and distribute cloth water filters bringing a reduction in disease incidence in some areas. It was also seen that generally low standards of living exacerbated by scattered outlying settlements made self-help difficult. Unfortunately occasional government and private efforts did not succeed because of a lack of community participation. Programme planners must involve the consumers in diagnosing these community characteristics and in planning, supervising and maintaining the resulting projects. The multi-strategy approach will help avoid wasted resources and false expectations that arise when project staff attempt to apply a "magic bullet" solution to a complex problem.  相似文献   
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Objective. To review imaging studies of isolated involvement of the sacrum due to tuberculosis and determine the role of imaging in the diagnosis and management of these patients. Design and patients. A retrospective analysis of 15 cases of isolated sacral tuberculosis imaged with MR imaging was performed. The CT images were also reviewed where available, and the various lesion characteristics were identified. We also reviewed the medical records in an attempt to determine the impact of the imaging studies on the management of these patients. Results. Fifteen patients (5 male, 10 female) presented with symptoms of 3–15 months’ duration. Chronic localized backache with muscle spasm was the commonest presenting symptom; discharging sinuses with abscess formation was found in six patients, five of whom were children. MR imaging of the sacrum revealed a hypointense marrow signal on T1-weighted images and hyperintense signal on T2-weighted images in 14 of 15 patients, the S2 vertebra being always involved. CT revealed osteolytic changes in the sacrum in all the five patients in whom CT was performed. All patients showed marked clinical improvement within 1 year of anti-tuberculous chemotherapy. Conclusion. Isolated tuberculosis of the sacrum is uncommon but should be suspected in patients presenting with chronic low backache or children with discharging sinuses/abscesses and showing sacral destruction on CT or MR imaging. MR imaging can identify cases and enables early institution of anti- tuberculous chemotherapy. Received: 31 August 1999 Revision requested: 1 November 1999 Revision received: 27 March 2000 Accepted: 14 April 2000  相似文献   
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The influence of natural beta-cyclodextrin and its hydrophilic derivatives (HPbetaCd and SBE7betaCd) on the in vitro dissolution rate, in vivo absorption and oral bioavailability of a poorly water soluble anti-inflammatory agent, valdecoxib (VALD) was studied. Equimolar drug-cyclodextrin solid complexes were prepared by kneading and coevaporation methods and characterized by infrared spectroscopy, differential scanning calorimetry, X-ray diffraction. In the liquid state, the cyclodextrin complexes were studied using phase solubility analysis, (1)H nuclear magnetic resonance and circular dichroism spectroscopy. Drug solubility and dissolution rate in distilled water were notably improved by employing the betaCds. The DP(15) (i.e. percent of dissolved VALD at 15 min) was 10.5% for the pure drug and 50, 91 and 93% for VALD-betaCd, VALD-HPbetaCd and VALD-SBE7betaCd complexes, respectively. Moreover, it was found that in the, the cyclodextrin complexes of drug showed significant improvement in the anti-inflammatory activity.  相似文献   
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BACKGROUND: Duplicated collecting systems comprises renal units containing two pyelocalyceal systems associated with a single ureter or double ureters and is the most common upper tract anomaly. CASE: This report presents a rare entity: an adult woman who had giant hydroureter of upper-pole moiety of the duplex kidney, which was an incidental finding during cesarean section. Heminephroureterectomy was done containing 2 L of fluid. This case is the first of its kind during cesarean section. CONCLUSION: The cause of this unusually massive degree of dilatation of the upper-pole moiety of the duplicated collecting system is uncertain, but may have resulted from an error in the development or because of VUR. We suggest mandatory intraabdominal examination after delivering uterus while conducting a cesarean section.  相似文献   
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A major complication of L-asparaginase used in the treatment of paediatric malignancies in children is pancreatitis (2%-16%). However, only seven paediatric cases of pancreatic pseudocyst caused by the utilization of the agent have been reported in literature. We present the case of a 5-year old girl who had abdominal pain and epigastric dullness after the third course of BMF-95 protocol with a diagnosis of ALL. A pancreatic pseudocyst of 10 χ 10 cm size was found by abdominal tomography. The cyst was treated by percutaneous external drainage, total parenteral nutrition (TPN), administration of octreotide and antibiotherapy for one month. Percutaneous external drainage has proven to be an effective, noninvasive method in this special case with a systemic disorder and the high risk of mortality should a surgical intervention have been performed.  相似文献   
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