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If proven effective, vaginal microbicides and diaphragms will likely be part of a larger HIV prevention model that includes condoms and other prevention strategies. It is, therefore, important to understand how introducing new prevention methods may affect overall patterns of sexual risk behavior. Data presented were collected as part of a safety and feasibility study of ACIDFORM gel with a diaphragm among 120 women in South Africa. Interviews were administered at enrollment and months 1, 3, 5, and 6 of the trial. Focus groups were conducted at trial exit. Frequency of sex increased significantly after enrollment. This increase appears to be owing to perceived protection from HIV and greater sexual pleasure afforded by the gel. Male condom use was high overall but increased significantly from enrollment. Data suggest this is because of increased partner involvement, increased negotiating power afforded by study participation, and provision of free condoms perceived to be of high quality.  相似文献   
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Summary This paper deals with a particular aspect of speech motor control in patients suffering from apraxia of speech. Three experiments are reported concerning the phase relations between individual speech gestures. These include the timing of laryngeal, velar and labial movements relative to lingual gestures.A total of 8 patients and 12 normal controls were examined using speech material which was designed according to appropriate phonetic paradigms. Evaluation was performed on the basis of speech signal parameters referring to the kinematics of inter-articulatory phasing. Deviations of the patient group were found in all three experiments. This suggests that disturbed phase relations of individual speech movements are a general feature of apraxic speech. It is further hypothesized that the described motor symptoms are the origin of a variety of phonemic errors. Support for this view is provided by appropriate examples which refer to the examined paradigms. By this argument, much of the disturbed phonemic structure of apraxic speech may be accounted for by timing deficits.  相似文献   
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Ohne ZusammenfassungDie vorstehende Arbeit ist im Laboratorium des Herrn Prof. Cyon in der medicinischen Academie in St. Petersburg ausgeführt.  相似文献   
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Management of upper gastrointestinal bleeding because of erosion of vessels by esophageal cancer may be challenging. We present herein the angiographic images of a 49-year-old patient who was admitted with massive bleeding from a tumor-eroded inferior thyroid artery. Attempts to control the bleeding by means of flexible endoscopy and insertion of a Sengstaken–Blakemore tube had failed. The diagnosis was impressively demonstrated by multislice computed tomography with intravenous contrast in the arterial phase and multiplanar reconstructions (computed tomography angiography) and by digital subtraction angiography. The bleeding was successfully treated with superselective catheterization and coiling of the eroded vessel.  相似文献   
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Humoral immune aberrations may occur in the cerebrospinal fluid (CSF) of patients with lymphoproliferative and other neoplastic diseases infiltrating the central nervous system (CNS). Such aberrations may be of diagnostic importance. We therefore studied CSF and serum from 47 patients with lymphoproliferative diseases and from 16 patients with various nonlymphoid neoplasias; 17 patients and 12 patients, respectively, had neoplastic CNS involvement. Elevated CSF IgM index and oligoclonal IgG bands in CSF and serum were commonly found, especially in patients with CNS involvement. Cerebrospinal fluid IgG and IgA indexes were usually normal. Increased CSF to serum albumin ratio, reflecting blood-brain barrier dysfunction, and increased CSF beta 2-microglobulin concentration were most common in patients with CNS involvement. The results indicate that neoplastic CNS disease should be borne in mind when CSF humoral immune aberrations are found.  相似文献   
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