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991.
Abstract The purpose of the study was to validate an instrument that measures health counseling practices of occupational health nurses. The measure, the health habits counseling questionnaire (HHCQ), was derived from a model of physician counseling practices. The health habits included smoking, alcohol, weight management, and exercise. Safety at work was added for this random sample of California occupational health nurses. Reliability was comparable to original findings for a random sample of physicians drawn from the roster of a western medical society. The validity of the hypothesized global constructs of aggressiveness and indications was not supported. Physicians in the normative sample were more likely to use primary prevention as an indication for counseling. Overall, occupational health nurses and medical society physician members were similar on many aspects of their counseling, although some significant differences did exist.  相似文献   
992.
993.
Computed tomography was used to evaluate mediastinal lymph nodes in 97 patients with nonsmall cell lung cancer. All patients had thorough surgical-pathological determination of mediastinal node status. Twenty-three patients were found to have metastatic lymph nodes. The usual lymphatic pathways of tumor spread into the mediastinum were defined using the node mapping scheme suggested by the American Thoracic Society. We considered mediastinal nodes abnormal when the short axis of the largest mediastinal node in the lymphatic drainage territory of the cancer was greater than or equal to 10 mm and the difference between this node and the largest node in the other territories is greater than 5 mm. The sensitivity was 78%, the specificity 99%, the positive predictive value 95%, the negative predictive value 94%, and the accuracy 94%. Comparing our method to those that used the size criterion alone, the number of false positives was reduced.  相似文献   
994.
995.
本文根据Svennerholm和蒋谷人等的方法略加改良,测定了蚌埠地区113例正常人,71例恶性肿瘤患者和82例非肿瘤疾病患者血清脂质结合唾液酸(LSA)的含量。正常值为12.4mg/dl(SD=±3.6mg/dl),71例不同肿瘤患者的平均值为28.2mg/dl(SD=±9.7mg/dl),阳性率为88.7%,82例非肿瘤疾病患者的平均值为16.82mg/dl(SD=±5.4mg/dl),假阳性率为17%。方法的灵敏度,重复性(平均CV=3.6%)和回收率(平均回收率=101.4%)测定结果是满意的。本研究的初步结果表明,血清LSA测定对肺癌、白血病、胃癌和食管癌具有一定的临床诊断价值。  相似文献   
996.
997.
A retrospective study on the value of magnetic resonance imaging (MRI) in replacing contrast studies of the lumbar spine has been undertaken. Studying pre- and postoperative conditions, the authors attempted to answer the question, Will MRI replace myelography? In this retrospective study, comparison is made in 20 patients between MRI and myelography and with 12 intra-operative findings. The overall impression was that MRI is equally sensitive as the invasive myelogram in diagnosing both protruded lumbar discs and postoperative fibrosis. The practical conclusion was an almost complete abandonment of myelography.  相似文献   
998.
999.
1000.
The optimal conditions for inactivation of Bordetella pertussis organisms with glutaraldehyde for the production of a safe and potent whole cell pertussis vaccine were investigated. Two bacterial harvests from B. pertussis strain 10536 were treated with glutaraldehyde, each with 0.025, 0.05 and 0.1% concentrations of glutaraldehyde for 10, 60 and 120 min. The nine types of glutaraldehyde-inactivated pertussis vaccine (GIPV) and conventional heat-inactivated pertussis vaccine (HIPV) preparations made from two bacterial harvests were comparatively evaluated for the mouse weight gain test (MWGT), potency, and the histamine-sensitization (HS) and leucocytosis-promoting-factor (LPF) tests. The minimum period for killing the B. pertussis organisms with glutaraldehyde was>10 min for 0.025%, 10 min for 0.05% and 5 min for 0.1% concentration. The average loss in opacity varied from 5 to 10% for GIPV preparations and was 14% for HIPV preparations. The GIPV preparations except those inactivated with 0.025% glutaraldehyde for 10 min (GIPV-A) were much less toxic than the HIPV preparations in the MWGT. The GIPV-A preparations did not pass the MWGT. The GIPV preparations were also much less toxic in HS and LPF tests than the HIPV preparation. The potency of GIPV preparations inactivated with 0.05% glutaraldehyde for 10 min (GIPV-D) was similar to that of HIPV preparations. The prolonged treatments with glutaraldehyde reduced the potency. The GIPV-D preparation with good potency and less toxicity was found to be inactivated with glutaraldehyde under optimal conditions. All the preparations were innocuous in the abnormal toxicity test.  相似文献   
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