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71.
Adenomatous lesions of the large bowel: an autopsy survey.   总被引:12,自引:0,他引:12  
A comprehensive autopsy survey of the large bowel showed that adenomas were very common lesions occurring in about one-half of the 518 cases studied. The great majority were small adenomatous polyps (tubular adenomas), 86.7% measuring less than 10 mm in diameter. Adenomas with a more complex tubulovillous pattern were larger with a mean diameter of 19.0 mm. There was no apparent incresae in mean size of adenomas with age. Nineteen clinically unsuspected cancers were discovered. Fourteen (8 in situ and 6 invasive) cancers had areas of residual benign adenoma. Five invasive cancers had no residual benign component. No in situ carcinomas or small (less than 10 mm) invasive cancers not containing residual adenoma were found. The results suggest that, although adenomas of the large bowel are very common, the vast majority are simple adenomatous polyps which do not undergo progressive growth and malignant change. Conversely, it appears that cancers may arise from benign adenomas which have the characteristics of large size and a more complex villous architecture.  相似文献   
72.
BACKGROUND: Neutropenia is a common side effect of chemotherapy, often requiring hospitalization for treatment of severe cases. Neutropenia hospitalization (NH) rates have been reported in individual studies, but national estimates are needed. METHODS: Chemotherapy-induced NHs were identified in the 1999 hospital discharge data bases from 7 states. Cancer and chemotherapy prevalence data from the National Cancer Institute's Surveillance, Epidemiology, and End Results Program and the National Cancer Data Base were used to calculate national NH rates for 13 cancer types. NH cost was estimated by multiplying charges by institution-specific, cost-to-charge ratios from the 1999 Centers for Medicare and Medicaid Services Hospital Cost Report. NH incidence was projected to national levels using population data from the United States Census and the Centers for Disease Control and Prevention. RESULTS: There were 20,780 discharges with documentation of cancer, chemotherapy, and neutropenia identified. Projecting to national levels, NH incidence was estimated at 60,294 cases (7.83 cases per 1000 cancer patients). The mean NH cost was 13,372 dollars. The mortality rate among patients with NH was estimated at 6.8% or 1 death for every 14 hospitalized patients. Among 13 selected cancer types, the NH rate was 34.20 cases per 1000 patients receiving chemotherapy (1 in 29 patients). NH was particularly common in patients with hematologic tumors, with an incidence of 43.3 cases per 1000 patients with such tumors (1 in 23 patients). The average NH cost for hematologic malignancies was 20,400 dollars, more than double the cost of NH for solid tumors. CONCLUSIONS: According to the current study, NH affects > 60,000 patients with cancer each year in the United States, with an average cost of 13,372 dollars per hospitalization and an associated inpatient mortality rate of 6.8%.  相似文献   
73.
BACKGROUND: According to the 2002 National Immunization Survey (NIS), vaccination coverage with recommended vaccines among U.S. children aged 19 to 35 months remained near all-time highs. Sustaining this high coverage requires significant effort, including consideration of parental vaccine safety concerns that have led to decreasing coverage in other countries. METHODS: The Parental Knowledge and Experiences module was administered to a random subset of NIS respondents from July 2001 to December 2002. The module included questions regarding attitudes toward vaccine safety and side effects, simultaneous vaccine administration, and acceptance of new vaccines. Multivariate logistic regression analyses examined associations between attitudes and up-to-date (UTD) vaccination coverage (four or more doses of diphtheria and tetanus toxoids and pertussis vaccine, three or more doses of poliovirus vaccine, one or more doses of any measles-containing vaccine, three or more doses of Haemophilus influenzae type b vaccine, and three or more doses of hepatitis B vaccine), while controlling for demographics. RESULTS: Ninety-three percent of parents rated vaccines as safe, 6% as neither safe nor unsafe, and 1% as unsafe. After adjusting for demographics, parental safety belief was significantly associated with the child's vaccination status. For children whose parents believed vaccines are safe, the odds of being UTD were 2.9 times the odds of being UTD for children of parents who believed vaccines are unsafe (75% vs 53%, respectively). Children whose parents were neutral about the safety of vaccines had vaccination coverage similar to children whose parents believed vaccines are unsafe. CONCLUSIONS: A significant association with vaccine coverage was found for a small group of parents with high vaccine safety concerns. Strategies focused on safety concerns may yield better protection for these children.  相似文献   
74.
Herpetic esophagitis   总被引:1,自引:0,他引:1  
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75.
76.
Studies were conducted to elucidate the processes involved in the biological disposition of diethylstilbestrol (DES). The apparent biological half-life of [14C] DES decreased with increasing age in immature rats. The half-life of DES in adult rats (14 min) was reached between the 15th and 25th day after birth. Comparison of the intestinal absorption of [14C] DES and [14C]DES monoglucuronide showed the unconjugated drug to be absorbed much more rapidly. Hydrolysis of the conjugate took place in the lower intestine, and this permitted the drug to undergo enterohepatic cycling.  相似文献   
77.
Two patients had colonic perforation as a result of percutaneous nephrostomy placement followed by track dilatation and renal calculus removal. We present the technical aspects of nephrostomy placement and stone removal, as well as the clinical diagnosis and management of these cases. Both patients recovered well with conservative therapy and required no surgical intervention. This report reviews the anatomic considerations for percutaneous nephrostomy in patients undergoing renal stone removal.  相似文献   
78.
79.
A series of N-(1,3-thiazol-2-yl)pyridin-2-amine KDR kinase inhibitors have been developed that possess optimal properties. Compounds have been discovered that exhibit excellent in vivo potency. The particular challenges of overcoming hERG binding activity and QTc increases in vivo in addition to achieving good pharmacokinetics have been acomplished by discovering a unique class of amine substituents. These compounds have a favorable kinase selectivity profile that can be accentuated with appropriate substitution.  相似文献   
80.
Treatment of palmar hyperhidrosis with intracutaneous injections of botulinum toxin type A is painful, making anesthesia desirable. However, nerve blocks may be associated with reduced efficacy. In 20 patients with idiopathic palmar hyperhidrosis both palms were treated with intracutaneous injections of botulinum toxin type A after having randomly chosen one hand for anesthesia by median und ulnar nerve block and the other hand for cooling. There was no difference in efficacy of botulinum toxin A treatment between both palms but significantly greater injection pain after cooling compared with nerve block.  相似文献   
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