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161.
We used a Chinese hamster ovary cell line that had been transfected with the human tumor necrosis factor (TNF) gene and constitutively produced TNF when transplanted in nude mice to study the effects of continuous production of TNF on calcium homeostasis. Continuous exposure to TNF caused increased osteoclastic bone resorption and humoral hypercalcemia in these animals. The mice bearing TNF-producing tumors were significantly hypercalcuric compared to mice bearing control tumors, but urinary cAMP excretion was unchanged. Mice bearing Chinese hamster ovary cell tumors containing the empty vector did not demonstrate hypercalcemia or increased bone resorption. This model system using transfected cells to continuously produce cytokines in vivo is more analogous to the pathophysiological conditions present in patients than intermittent injections and can produce much longer exposures than infusion pumps. Such model systems should allow a better understanding of the role of factors involved in humoral hypercalcemia.  相似文献   
162.
The clinical-pathologic records of 178 women with stage IB squamous cell carcinoma treated by radical hysterectomy and pelvic node dissection were reviewed to assess prognostic factors and outcome in relation to adjunctive pelvic radiation. Among 32 women with pelvic nodes metastases, 19 treated with adjunctive radiation had longer recurrence-free intervals and more extrapelvic metastases than 13 nonirradiated women. However, among irradiated women recurrences were more rapidly fatal, so that the survival of the two groups was similar. Among 54 women with deeply invading (10 mm or more) carcinomas confined to the uterus, 17 with adjunctive radiation had recurrence-free intervals and survivals similar to 37 women without radiation, despite more high-risk factors in the irradiated group. The findings suggest that adjunctive pelvic radiation may control pelvic recurrence but not extend survival.  相似文献   
163.
Papillary villoglandular carcinoma of the cervix   总被引:1,自引:0,他引:1  
Three cases of papillary villoglandular carcinoma of the cervix are presented. Each patient was multiparous and presented with abnormal vaginal bleeding. The mean age at presentation was 35 years (range 28-42 years). All patients were staged as FIGO IB and underwent radical Wertheim hysterectomy and bilateral pelvic lymphadenectomy. Disease was limited to the cervix in two patients and extended to involve the lower uterine segment in one patient. There was no evidence of microscopic spread to the lymph nodes. Previous reports that examined patients with papillary villoglandular carcinoma of the cervix found them to have a favorable prognosis. Treatment implications are discussed.  相似文献   
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165.
This study evaluated the prevalence of upper respiratory symptoms (URS) among patients with symptomatic gastroesophageal reflux disease (GERD). Seventy-four subjects with heartburn completed a URS questionnaire before dual-probe, 24-h esophageal pH monitoring. The URS questionnaire was also completed by 74 normal volunteers without previous or current symptoms of GERD. Esophageal pH monitoring results were classified as normal, distal, or proximal and distal gastroesophageal reflux using standardized criteria. Mean URS scores (+/- SD) were 8.31 +/- 3.98 in the 52 subjects with GERD and 4.57 +/- 3.57 in the 22 subjects with negative pH probe studies, p = 0.02. Subjects with negative pH probe studies and normal volunteers scored similarly on the URS questionnaire. Reflux episodes/24 h correlated with URS scores, r = 0.47, p = 0.0001. Seventy-five percent of subjects with upper reflux, 68% of subjects with lower reflux, 36% of subjects with normal esophageal pH studies, and 9% of normal volunteers reported laryngeal symptoms for at least 5 d/mo. Sixty-nine percent of subjects with upper reflux, 50% of subjects with lower reflux, 31% of subjects with normal pH studies, and 14% of normal volunteers reported nasal symptoms for at least 5 d/mo. URS are frequent among subjects with GERD. Keywords: rhinitis; upper airway; gastroesophageal reflux  相似文献   
166.
Purpose: To assess whether alcohol, tobacco, and other drug (ATOD) use in elementary school may have serious implications for continued ATOD use in middle school and beyond.

Methods: Longitudinal analyses were conducted on questionnaire data from 331 middle school students who had previously provided ATOD-use data during elementary school. Non-school personnel administered questionnaires in three participating school districts in three different states. The sample of students was ethnically and geographically diverse, including students from a range of low socioeconomic status backgrounds living in rural, urban or inner-city environments.

Results: Middle school alcohol use was almost three times as likely to occur if alcohol use had occurred in elementary school (OR = 2.94, p < .001). Elementary school use of tobacco and marijuana also greatly increased the likelihood of middle school use (OR = 5.35, p < .001 and OR = 4.25, p < .05, respectively).

Conclusions: Early use of ATOD is associated with greatly increased odds of later use, which has important implications for the timing of drug prevention programs. Preventive interventions designed for use in pediatric practice settings should commence no later than elementary school, during the middle childhood years.  相似文献   

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