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941.
Radioactive strontium-90 concentrations in baby teeth obtained from Suffolk County, New York, rose steadily during the 1980s. Recent levels of strontium-90 are similar to those reported for babies born in the late 1950s-at the height of atmospheric nuclear weapons testing in Nevada. Strontium-90 concentrations increased concomitantly with increases in cancer incidence among Suffolk children under the age of 5 y, a result that mimicked parallel trends observed in the 1950s and early 1960s. Given that effects of strontium-90 on developing cells are most pronounced during the fetal and infant periods, escalating levels should be viewed as a factor in the recent decline in various child health status measures.  相似文献   
942.
943.
A retrospective review of patients in our practice who underwent abdominal panniculectomy to facilitate gynecologic cancer surgerywas performed. The objective of the study was to determine if pannicu-lectomy was a safe and useful procedure in the morbidly obese gyneco-logic cancer patient. A total of 12 patients underwent the procedure between 1992 and 1996. Optimal pelvic oncologic surgery was accom-plished in all 12 patients. All aspects of those procedures were per-formed by gynecologic oncologists. The Buchwalter retractor was usedin all cases. The patients' weights ranged from 170 to 429 pounds, with a mean of 275 pounds. The mean body mass index was 48, with a range from 37 to 67. Four patients had a history of diabetes mellitus. Nine patients healed without wound complications. Three patients developed superficial subcutaneous wound infections/necrosis that were successfully managed with office debridement. Abdominal panniculectomy is a reasonably safe procedure that makes radical pelvic surgery possible regardless of the patient's weight. Prolonged wound bulb suction drainage may decrease the incidence of wound necrosis/infection in these high-risk patients.  相似文献   
944.
945.
Patients with sickle cell disease (SCD) are predisposed to infections. There is a paucity of recent information on the incidence of post-splenectomy infectious complications in these patients. The purpose of this study was to determine whether splenectomy increases infectious complications in SCD. Twenty-nine patients with SCD had splenectomy for sequestration crises at our hospital between 1988 and 1992; 16 of them received all of their follow-up care at our institution. These 16 charts were reviewed for infectious-related admissions, hospital days, days of IV antibiotics, positive cultures, and episodes of sepsis. For each patient, these parameters in the pre- and postoperative period were compared and expressed as number per year. The mean age at time of splenectomy was 2.5 ± 0.4 years and the mean follow-up was 4.5 ± 0.4 years. There was no significant difference in the pre- and postoperative periods for admissions, hospital days, days of IV antibiotics, positive cultures, or episodes of sepsis per year. There were also no operative deaths. The incidence of pre-splenectomy sepsis was 0.04 ± 0.03 episodes per year compared to 0.09 ± 0.04 (P = ns) episodes/year after splenectomy. Sepsis occurred at an average of 20.8 (range 2–30) months postoperatively; Streptococcus pneumoniae was the most common causative organism. The total mortality after splenectomy in SCD patients was 3.4% (1/29) over a nearly 5-year period. Although infections are common in children with SCD, there was no increase in infections or episodes of sepsis in SCD patients who underwent splenectomy. Accepted: 6 March 1997  相似文献   
946.
Four novel zinc (II)-substituted phthalocyanines, varying in charge and hydrophobicity, were evaluated in vivo as new photosensitizers for photodynamic therapy. Two rat tumours with differing vascularity were used: a mammary carcinoma (LMC1) and a fibrosarcoma (LSBD1), with vascular components six times higher in the latter (10.8%+/-1.5) than in the former (1.8%+/-1.4). Each sensitizer was assessed for tumour response relative to normal tissue damage, and optimum doses were selected for further study, ranging from 0.5 to 20 mg kg(-1). Interstitial illumination of the tumours was carried out using a 200-microm-core optical fibre with a 0.5 cm length of diffusing tip, at either 680 or 692 nm, depending on the sensitizer. Light doses of between 200 and 600 J were delivered at a rate of 100 mW from the 0.5-cm diffusing section of the fibre. Maximum mean growth delays ranged from 9 to 13.5 days depending on sensitizer and type of tumour, with the most potent photosensitizer appearing to be the cationic compound. Histopathological changes were investigated after treatment to determine the mechanism by which tumour necrosis was effected. The tumours had the appearance of an infarct and, under the conditions used, the observed damage was shown to be mainly due to ischaemic processes, although some direct tumour cell damage could not be ruled out.  相似文献   
947.
The results of radiotherapy for brainstem tumors   总被引:2,自引:0,他引:2  
Objective: This analysis was performed to examine the outcome of adult and pediatric patients with brainstem tumors. Methods and materials: Forty patients with brainstem glioma were evaluated retrospectively. Included were 24 females and 16 males ranging in age from 3 to 81 years (median, 29.5 years). These patients were treated with various combinations of surgery, chemotherapy, and ratiotherapy (RT). The length of follow-up in survivors ranged from 0.6 to 20 years (median: 3.2 years, mean: 6 years). Survival rates were calculated with the Kaplan Meier method and differences between survival curves were calculated using the log-rank test. Results: The overall 2 and 5-year survival rates were 44% and 34%, respectively. The median survival time was 19 months. The 5-year survival rate was 54% for patients with tumors outside the pons compared to 21% for those with tumors involving the pons (p=0.04). The 5-year survival rate was 59% for patients with exophytic tumors as compared to 23% for those with intrinsic tumors (p=0.05). Patients undergoing subtotal resection had a 5-year survival rate of 53% compared to 28% for those having only a biopsy or no surgical intervention (p=0.04). None of the other potential prognostic or treatment related factors evaluated [patient age, tumor grade, tumor histology, radiotherapy parameters (including BID fractionation, 3-D treatment planning, or the use of doses > 55 Gy), or the administration of adjuvant chemotherapy] evaluated were associated with patient survival. Conclusions: Brainstem gliomas generally occur in younger individuals. The survival rates were better for patients with exophytic tumors, those involving sites other than the pons, and tumors amenable to subtotal resection. Improvements in the outcome of patients with brainstem gliomas will require new therapeutic approaches.  相似文献   
948.
Objectives: To investigate dietary factors for squamous cell esophageal cancer and whether these factors may contribute to the five-fold higher incidence of this cancer in the black versus white population of the United States.Methods: Data from a food frequency questionnaire were analyzed for 114 white men and 219 black men with squamous cell esophageal cancer, and 681 white and 557 black male controls from three areas of the United States who participated in a population-based case-control study of esophageal cancer.Results: Protective effects were associated with intake of raw fruits and vegetables (odds ratio for high versus low consumers=0.3 in both white and black men) and use of vitamin supplements (especially vitamin C; odds ratio for high versus low consumers=0.4 in both races), with the frequency of consumption of raw fruits and vegetables and vitamin supplements being greater for white than black controls. In addition, elevated risks were associated with high versus low intake of red meat (OR=2.7 for blacks and 1.5 for whites) and processed meat (OR=1.6 for blacks and 1.7 for whites), with the levels of consumption being greater for black than white controls.Conclusions: In the United States, these dietary factors may contribute in part to the much higher incidence of squamous cell esophageal cancer among black compared to white men.  相似文献   
949.
Objective To assess the impact of pregnancy upon continence and constipation.
Design A questionnaire survey.
Setting Maternity wards in the Rotunda Lying In Hospital, Dublin, Republic of Ireland.
Population 7771 women who were delivered of liveborn infants.
Methods Questionnaires were delivered and collected by physiotherapy staff as part of routine postnatal care.
Results Analysis of data using χ2 tests showed significant differences between three parity groups [primigravidae, multigravidae (2–4) and multigravidae (5+)] for symptoms of both urinary incontinence (  χ2= 119.54  , df = 2, P = 0.000) and constipation (  χ2= 12.53  , df = 3, P = 0.002); the incidence of both constipation and urinary incontinence increased with parity.
Conclusion The results of this survey have emphasised the relation between parity and postpartum incontinence which stresses the importance of early diagnosis and intervention.  相似文献   
950.
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