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991.
992.
Forty-two evaluable endomyocardial biopsies were obtained from 29 patients treated with epirubicin, the 4'-epimer of doxorubicin in cumulative doses ranging from 147 mg/m2 to 888 mg/m2. In this study of the Northern California Oncology Group, myofibrillar loss and sarcoplasmic vacuolization were identified and shown to be identical to those previously described for doxorubicin. However, when these biopsies were compared to 119 biopsies obtained from 98 patients treated with doxorubicin, milligram for milligram, epirubicin caused less endomyocardial injury than doxorubicin (P = 0.0013). Age, sex, type of primary malignancy, prior cardiac disease, and hypertension did not influence the degree of histologically demonstrated anthracycline injury induced by epirubicin.  相似文献   
993.
994.
Oxacillin susceptibility of coagulase negative staphylococci as assessed by conventional methods was confirmed by a modified Etest method, extended to detect heteroresistance. Verification of susceptibility was followed by successful treatment for six consecutive children with deep seated infections. Physicians' trust in such a validated method will contribute to the appropriate use of antibiotics.  相似文献   
995.
Cobb  SR; Mehringer  CM 《Radiology》1987,162(2):521-522
Wallerian degeneration in the corticospinal tract was demonstrated by magnetic resonance (MR) imaging in a patient with Schilder disease. The histochemical stages of myelin breakdown that allow its demonstration by MR imaging are reviewed.  相似文献   
996.
Evidence supporting a broad role for the inactivation of the p53 gene in human tumorigenesis has been provided by studies showing that the p53 gene is mutated in many human cancers. In this study, we report on the mutational status of the p53 gene in prostate cancer cells and provide functional evidence that the wild-type p53 gene may have a role in suppressing prostatic tumorigenesis. Sequence analysis of exons 5-8 of the p53 gene reveals that three of five prostate cancer cell lines (TSUPr-1, PC3, DU145) contain mutations which alter the amino acid sequence of this most highly conserved portion of the gene. One of two primary prostatic cancer specimens examined also contained a mutation in this region. Transfection of the wild-type p53 gene versus a mutated p53 gene into two cell lines with p53 mutations results in reduced colony formation. Wild-type p53 gene expression is apparently incompatible with continued growth of these tumor cells inasmuch as none of the colonies which formed after wild-type transfections retain the transfected p53 sequences. Immunocytochemical data indicate that prostate carcinoma cells expressing the transfected wild-type p53 gene are growth arrested because they exhibit a reduced level of thymidine incorporation into DNA. This study is the first report of p53 gene mutations in prostate cancer cells and suggests a functional role for the p53 gene in suppressing prostatic tumorigenesis.  相似文献   
997.
OBJECTIVE: Patients must remain immobile for magnetoencephalography (MEG) and MRI recordings to allow precise localization of brain function for pre-surgical functional mapping. In young children with epilepsy, this is accomplished with recordings during sleep or with anesthesia. This paper demonstrates that MEG can detect, characterize and localize somatosensory-evoked fields (SEF) in infants younger than 4 years of age with or without total intravenous anesthesia (TIVA). METHODS: We investigated the latency, amplitude, residual error (RE) and location of the N20m of the SEF in 26 infants (mean age=2.6 years). Seventeen patients underwent TIVA and 9 patients were tested while asleep, without TIVA. RESULTS: MEG detected 44 reliable SEFs (77%) in 52 median nerve stimulations. We found 27 reliable SEFs (79%) with TIVA and 13 reliable SEFs (72%) without TIVA. TIVA effects included longer latencies (p<0.001) and lower RE (p<0.05) compared to those without TIVA. Older patients and larger head circumferences also showed significantly shorter latencies (p<0.01). CONCLUSIONS: TIVA resulted in reliable SEFs with lower RE and longer latencies. SIGNIFICANCE: MEG can detect reliable SEFs in infants younger than 4 years old. When infants require TIVA for MEG and MRI acquisition, SEFs can still be reliably observed.  相似文献   
998.
An assessment of the three part differential provided by the Coulter STKR blood counter showed good correlation when compared with an 800 cell manual differential. Satisfactory flagging of eosinophilia, basophilia, and the presence of immature cells was found. The use of variables derived from the STKR in conjunction with interpretive reporting and user-defined flagging enabled this department to reduce considerably the numbers of films requiring manual differential counts.  相似文献   
999.
We investigated the relation between alcohol consumption and breast cancer in the Epidemiologic Follow-up Study of the first National Health and Nutrition Examination Survey, a cohort study based on sample of the U.S. population. A total of 7188 women 25 to 74 years of age who were examined during the period 1971 through 1975 were included in the analysis. Information about alcohol consumption was obtained during the base-line interview. The median follow-up period for this cohort was 10 years. One hundred twenty-one cases of breast cancer that developed after the baseline examination were identified through hospital records or death certificates. The relative-risk estimate for any amount of drinking relative to no drinking was 1.5 (95 percent confidence interval, 1.1 to 2.2). The estimates for three levels of consumption, from the lowest to the highest, were 1.4 (confidence interval, 0.9 to 2.3), 1.5 (0.9 to 2.6), and 1.6 (1.0 to 2.7), in comparison to no drinking at all. These relative-risk estimates were not materially affected by adjustment for known risk factors for breast cancer or for several dietary factors. The results of this study, consistent with those of two other cohort studies and a number of case-control studies, suggest that moderate alcohol consumption is associated with an elevation in the risk of breast cancer of 50 to 100 percent.  相似文献   
1000.
A questionnaire survey of 562 physicians in Manitoba who had graduated from the University of Manitoba was carried out to assess the effect of personal characteristics on choosing a practice location. The results closely resemble those of studies performed in the United States: the choice of a nonurban practice location is significantly more likely if the physicians and their spouses have nonurban backgrounds and if the physicians have had a nonurban preceptorship during undergraduate medical education. In this study practitioners who were male and whose fathers were farmers or health care professionals were also more likely to practise in nonurban areas. These findings will help in making physician distribution more equitable.  相似文献   
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