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Cell-CAM 105 has been identified as a cell adhesion molecule based on the ability of anti-cell-CAM 105 monospecific Fab fragments to inhibit the reaggregation of rat hepatocytes. Because of its adhesive properties, it was expected that cell-CAM 105 would be present on the lateral cell surface where adhesive interactions predominate. Paradoxically, however, immunofluorescence analysis of frozen sections of rat liver using specific monoclonal antibodies indicated that cell-CAM 105 was present exclusively in the bile canalicular domain of the rat hepatocyte where there is no intercellular adhesion. To more precisely define the in situ localization of cell-CAM 105, immunoperoxidase labeling and electron microscopy were used to examine intact and mechanically dissociated liver tissue. Results showed that when accessibility was provided by mechanical dissociation of perfusion fixed liver tissue, cell-CAM 105 could be detected in the pericanalicular region of lateral membranes. In contrast, when hepatocytes were labeled after incubation in vitro under conditions used during adhesion assays to induce reaggregation, cell-CAM 105 rapidly redistributed to all areas of the plasma membrane. Immunofluorescence analysis of primary hepatocyte cultures further revealed that cell-CAM 105 and two other bile canalicular proteins relocalized to discrete domains reminiscent of bile canaliculi, whereas cell-CAM 105 was also present in areas of intercellular contact. Serial section electron microscopy analysis of well-defined, cross-sectional profiles of bile canaliculi suggested the presence of cell-CAM 105-positive membrane folds that extended along the length of the bile canalicular border. In sections from livers in which calcium-dependent adhesive contacts had been disrupted by treatment with ethylenediamine tetraacetate, intact bile canaliculi were found that remained attached only by these border folds. The implications of these results are discussed with regard to a possible role for cell-CAM 105 in bile canalicular formation.  相似文献   
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OBJECTIVES: This study examined whether there are systematic differences between the Behavioral Risk Factor Surveillance System (BRFSS) and the Current Population Survey (CPS) for state cigarette smoking prevalence estimates. METHODS: BRFSS telephone survey estimates were compared with estimates from the US Census CPS tobacco-use supplements (the CPS sample frame includes persons in households without telephones). Weighted overall and sex- and race-specific BRFSS and CPS state estimates of adults smoking were analyzed for 1985, 1989, and 1992/1993. RESULTS: Overall estimates of smoking prevalence from the BRFSS were slightly lower than estimates from CPS (median difference: -2.0 percentage points in 1985, -0.7 in 1989, and -1.9 in 1992/1993; P < .05 for all comparisons), but there was variation among states. Differences between BRFSS and CPS estimates were larger among men than among women and larger among Blacks than among Hispanics or Whites; for most states, these differences were not significant. CONCLUSIONS: The BRFSS generally provides state estimates of smoking prevalence similar to those obtained from CPS, and these are appropriate for ongoing state surveillance of smoking prevalence.  相似文献   
4.
C Mowery  M Botte  G Bradley 《Orthopedics》1987,10(2):309-313
Aseptic loosening is the most common mode of failure for total knee replacements. Component breakage is rare, usually attributable to errors of design or manufacture. A case is presented in which rotational malplacement of the femoral component resulted in accelerated wear and eventual fracture of the polyethylene tibial component.  相似文献   
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PURPOSE: To estimate the independent effect of cigarette smoking on respiratory tract symptoms and health status indicators among high school seniors. DESIGN: Consolidated data sets from one-time cross-sectional survey designs. SETTING: High schools in the United States, 1982-1989. SAMPLE: A total of 26,504 high school seniors, with an 83% response rate. MEASURES: Odds ratios for respiratory tract symptoms and health status indicators for cigarette smokers compared with nonsmokers, while controlling for sex, socioeconomic status, and use of other drugs. RESULTS: High school seniors who were regular cigarette smokers and who began smoking by grade nine were significantly more likely than never smokers to report shortness of breath when not exercising (adjusted odds ratio [OR] = 2.7), coughing spells (OR = 2.1), productive cough (OR = 2.4), and wheezing or gasping (OR = 2.6). These smokers were also more likely to have seen a doctor or other health professional for an emotional or psychologic complaint (OR = 3.0) and to rate their overall health as poorer than average (OR = 2.4). We found strong dose-response relationships for most outcome measures. CONCLUSIONS: Cigarette smoking among high school seniors is associated with respiratory tract symptoms and poorer overall physical health and may be a marker for underlying mental health problems. Smoking prevention activities directed at adolescents should include information on the early adverse health consequences of cigarette smoking.  相似文献   
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Introduction

The high mortality and morbidity associated with resection for oesophagogastric malignancy has resulted in a conservative approach to the postoperative management of this patient group. In August 2009 we introduced an enhanced recovery after surgery (ERAS) pathway tailored to patients undergoing resection for oesophagogastric malignancy. We aimed to assess the impact of this change in practice on standard clinical outcomes.

Methods

Two cohorts were studied of patients undergoing resection for oesophagogastric malignancy before (August 2008 – July 2009) and after (August 2009 – July 2010) the implementation of the ERAS pathway. Data were collected on demographics, interventions, length of stay, morbidity and in-hospital mortality.

Results

There were 53 and 55 oesophagogastric resections undertaken respectively for malignant disease in each of the study periods. The median length of stay for both gastric and oesophageal resection decreased from 15 to 11 days (Mann– Whitney U, p<0.001) following implementation of the ERAS pathway. There was no significant increase in morbidity (gastric resection 23.1% vs 5.3% and oesophageal resection 25.9% vs 16.7%) or mortality (gastric resection no deaths and oesophageal resection 1.8% vs 3.6%) associated with the changes. There was a significant decrease in the number of oral contrast studies used following oesophageal resection, with a reduction from 21 (77.8%) in 2008–2009 to 6 (16.7%) in 2009–2010 (chi-squared test, p<0.0001).

Conclusions

The introduction of an enhanced recovery programme following oesophagogastric surgery resulted in a significant decrease in length of median patient stay in hospital without a significant increase in associated morbidity and mortality.  相似文献   
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Objective: To report ventilation strategies, survival and complications in 39 outborn infants treated with high frequency oscillatory ventilation (HFOV).
Methodology Data were collected prospectively between 1 May 1992 and 31 December 1993 on all infants treated with HFOV who had severe respiratory failure despite optimal conventional ventilation.
Results Twenty-eight out of 39 (72%) survived. Of the 15 infants with birthweights <1500g, eight survived. Best survival rates were for infants with pulmonary interstitial emphysema with air leak (4/5) and for infants of birthweight >1500g with hyaline membrane disease (8/8), and meconium aspiration syndrome (7/7). Three infants deteriorated while on HFOV and required extracorporeal membrane oxygenation. Complications were: (i) development of pulmonary interstitial emphysema (1); (ii) recurrence of pneumothorax (3); (iii) hypotension (2); and (iv) bronchopulmonary dysplasia (9). One of the eight infants weighing <1500g who received HFOV in the first week of life developed periventricular haemorrhage.
Conclusion The initial results of HFOV for severe respiratory failure were encouraging although a learning curve was encountered with its introduction.  相似文献   
10.
OBJECTIVES: This study compared trends in adult cigarette smoking prevalence in California and the remainder of the United States between 1978 and 1994. METHODS: We used data from National Health Interview Surveys and Behavioral Risk Factor Surveillance System surveys to compare trends in smoking prevalence among persons 18 years and older. RESULTS: In both California and the remainder of the United States, the estimated annual rate of decline in adult smoking prevalence accelerated significantly from 1985 to 1990: to -1.22 percentage points per year (95% confidence interval [CI] = -1.51, -0.93) in California and to -0.93 percentage points per year (95% CI = -1.13, -0.73) in the remainder of the nation. The rate of decline slowed significantly from 1990 to 1994: to -0.39 percentage points per year (95% CI = -0.76, -0.03) in California and to -0.05 percentage points per year (95% CI = -0.34, 0.24) in the remainder of the United States. CONCLUSIONS: The presence of an aggressive tobacco control intervention has supported a significant decline in adult smoking prevalence in California from 1985 to 1990 and a slower but still significant decline from 1990 to 1994, a period in which there was no significant decline in the remainder of the nation. To restore nationwide progress in reducing smoking prevalence, other states should consider similar interventions.  相似文献   
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