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Background  

The objective of this study was to examine missed opportunities for participation in a prevention of mother-to-child transmission (PMTCT) programme in three sites in South Africa. A rapid anthropological assessment was used to collect in-depth data from 58 HIV-positive women who were enrolled in a larger cohort study to assess mother-to-child HIV transmission. Semi-structured interviews were conducted with the women in order to gain an understanding of their experiences of antenatal care and to identify missed opportunities for participation in PMTCT.  相似文献   
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We used a quantitative immunoassay to examine the effects of human serum and immunoglobulins on neurofilament protein expression in cultures of chick spinal neurons. Compared with cultures grown in the presence of serum from healthy controls or patients with other neurologic disorders, ALS serum lowered the level of neurofilament proteins. Effects were similar with or without muscle-derived neurotrophic factors; there was no specificity for motor neurons. No neurotoxic activity was found in immunoglobulin fractions, and there was no evidence of circulating antibodies that might neutralize muscle-derived neurotrophic factors or induce cytolysis of spinal neurons.  相似文献   
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One hundred patients with malignant biliary obstruction underwent palliative therapy by means of percutaneous transhepatic placement of 114 biliary endoprostheses. All patients were then followed up for at least 18 months or until death. Retrospective evaluation of the 95 patients who died showed an average survival time of 5.0 months. The five remaining patients have survived an average of 29.8 months. During the 1st week after stent insertion, a second manipulation was performed to improve stent function in nine patients. Overall, 14 (12.3%) of the stents became obstructed and six (5.2%) migrated; 86 patients required no further therapy for biliary obstruction or stent malfunction. The 30-day mortality rate was 12%; none of the deaths were directly attributable to a complication of the stent placement procedure.  相似文献   
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Needle core biopsy guided with mammography: a study of cost- effectiveness   总被引:2,自引:0,他引:2  
Lindfors  KK; Rosenquist  CJ 《Radiology》1994,190(1):217
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INTRODUCTION: Levetiracetam (LEV) is approved for use as add-on therapy in adult patients with partial epilepsy. It is apparent from clinical trials that up to 8% of previously drug-resistant patients may be rendered seizure-free by adding-on levetiracetam. As yet there is no way of predicting these unexpectedly responsive patients. We set out to identify our previously refractory patients who had demonstrated unexpected responsiveness to add-on therapy with levetiracetam, and compared these to patients who had not responded to the drug. We then attempted to characterise any clinical features that differentiated these groups of patients. METHODS: We included all patients with a history of present or previous exposure to levetiracetam who had been unresponsive to at least two other prior anti-epileptic drugs (AEDs) and recorded their demographic and clinical data. We divided response into (a) 'seizure-free' (seizure-free for a minimum of 6 months after commencing LEV); (b) 'partial > 50%' (greater than 50% reduction in seizures for a minimum of 6 months after commencing LEV); (c) 'honeymoon' (seizure-free for less than 6 months after commencing LEV and then returned towards baseline frequency); and (d) 'no-response'. For the purpose of analysis we considered the 'seizure-free' and 'partial > 50%' groups as 'responders', and the 'no response' group as 'non responders'. RESULTS: 344 patients were included in the analysis. Fifty-six patients (16.3%) were rendered seizure-free on levetiracetam. Idiopathic generalised epilepsy and post-traumatic partial epilepsy were more common in the responder than the non-responder group (p = 0.005 and 0.05 respectively). Lamotrigine was used significantly more often in combination with levetiracetam in responders than non-responders (p = 0.003). The mean daily dose of levetiracetam was lower in responders than non-responders. DISCUSSION: A higher than expected number of previously drug resistant patients was rendered seizure-free by add-on therapy with levetiracetam. Those who respond best appear to do so at relatively low doses and our data suggest the possibility of a beneficial pharmacodynamic interaction between levetiracetam and lamotrigine. We were unable to identify any clinical factors that clearly predicted which patients would become seizure-free and we hypothesise that response may be determined by genetic or molecular factors. All drug-resistant patients, including those being assessed for surgery, should be considered for a trial of levetiracetam, regardless of their epilepsy classification.  相似文献   
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Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy.  相似文献   
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Administration of repetitive sublethal doses of either recombinant human tumor necrosis factor (TNF) or recombinant murine gamma-interferon (IFN) to non-tumor-bearing (NTB) rats caused a significant decline in food intake and body weight. After 3 days rats became resistant to the anorectic and weight loss effects of TNF but maintained persistent diminished food intake and diminished body weight gain while receiving recombinant murine IFN. Passive immunization against recombinant rat gamma-interferon allowed cachectic tumor-bearing (TB) rats to eat more food, have a lesser decline in body weight, live longer, and tolerate larger tumors than similar TB rats given nonspecific control antibody. TB rats treated with an antisera to recombinant murine TNF, which was 100% protective when given to NTB rats 6 h before a lethal endotoxin challenge, did not differ significantly from TB rats treated with control antibody with respect to food intake, body weight, survival, or tumor size. Serum levels of TNF or IFN were not detectable in cachectic tumor-bearing rats. The data indicate that the administration of exogenous IFN can simulate cachexia in NTB rats and that passive immunization against it can partially reverse the cachectic changes associated with cancer and prolong survival. These findings suggest that gamma-interferon may be an important mediator of cachexia in this rat tumor model.  相似文献   
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