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Many of the white dot syndromes are considered to have a granulomatous pathogenesis. The histopathologic characteristics of this case of multifocal choroiditis seen within 15 months of apparent clinical onset show that the white dot lesions were nongranulomatous perivascular choroidal infiltrates, consisting mainly of B lymphocytes. Early choroidal neovascularization was also seen.  相似文献   
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Between September 1987 and April 1995, 33 totally implantable venous access devices (TIVADs) were implanted at the Cardiff Adult Cystic Fibrosis Centre, U.K., for the purpose of intermittent antibiotic therapy, including 22 PORT-A-CATH (Simcare Ltd.) devices (PCs) to 18 patients, and 11 P.A.S.PORT (Simcare Ltd.) devices (PPs) to nine patients. There were 50 complications during 25 824 days of catheter function which were severe enough to lead to removal of the devices in eight patients (six PCs and four PPs). Overall, patients' acceptance of these devices was excellent. Despite a shorter functional time and a higher rate of complications in PPs compared with PCs, PPs were preferred by many patients for cosmetic reasons. Totally implantable venous access devices provide safe, effective and convenient means of venous access in cystic fibrosis patients requiring intermittent antibiotic therapy.  相似文献   
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OBJECTIVE: To calculate and compare the costs of the treatment of varicocele by antegrade scrotal sclerotherapy with other modalities. PATIENTS AND METHODS: A total of 2305 operations using antegrade scrotal sclerotherapy to treat varicocele in childhood and adolescence were analysed for cost factors and compared with different surgical treatment methods for varicocele. RESULTS: Calculation of the pre-, intra- and post-operative costs showed that antegrade scrotal sclerotherapy was the most economically effective of all forms of surgical management for varicocele. CONCLUSIONS: Because antegrade scrotal sclerotherapy is a cost-effective treatment for varicocele, the indications for treatment may be widened to include more men with potential infertility, and thus avoid the need for expensive methods of artificial fertilization.  相似文献   
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On the basis of literature data and personal investigations the authors elaborated a scheme of detection of the causative agent of melioidosis in the objects of external environment, including fluorescent microscopy of crude material, seeding on meat-peptone agar with crystal violet, seeding material treated with penicillin on fluid medium with subsequent transfer on solid Levin medium and infection of animals, seeding on a medium with beta-alanine and neonmycin and infection of sensitive animals with crude material.  相似文献   
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Rapid sodium and slow input and output currents were studied by the double saccharose bridge method on isolated atrial trabeculae of Rana ridibunda under the effect of aconitin (100 mg/l). It is shown that the ptroperties of rapid sodium channels change under the effect of aconitin. As the result of this, activation of the input sodium current begins at potentials which are close to the rest potential, the maximum value of sodium conduction reduces, while the reverse potential for sodium current is shifted in the direction of lower potentials. Despite the effect of aconitin, the sodium current is blocked by tetrodotoxin (10-6M). Aconitin causes reversible reduction of the input calcium current but has no effect on the output current.  相似文献   
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