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41.
In contrast to the dramatic decrease in the overall incidence of gastric cancer, there has been a reported increase in the incidence of cases located in the gastric cardia. The aim of this study was to identify changes in site- and histology-specific incidence rates of gastric adenocarcinoma during a 50-year period. The Rochester Epidemiology Project medical records linkage system was used to identify all cases of gastric adenocarcinoma among residents of Olmsted County, Minnesota, between 1941 and 1990 (n = 342). Each patient's complete (inpatient and outpatient) medical records were reviewed and tumor location determined from pathological, surgical, endoscopic, and radiological reports. All available histological specimens (n = 246) were reviewed independently. The overall incidence of gastric cancer decreased from 48.8 per 100,000 person-years in the 1940s to 11.6 per 100,000 in the 1980s, whereas the incidence of adenocarcinoma of the cardia did not change significantly during the 50-year period. The incidence of adenocarcinoma of the esophagogastric junction increased from 0.0 to 1.9 per 100,000 person-years, but the number of cases was small. The incidence of adenocarcinoma of the gastric cardia has not increased in this population. The reported increase in cardia cancer in other populations may be due to an increasing incidence of adenocarcinoma of the esophagogastric junction.  相似文献   
42.
Lack of objective evidence of efficacy of laxatives in chronic constipation   总被引:6,自引:0,他引:6  
Laxatives are commonly used to treat constipation and can be bought over-the-counter in many countries, although some preparations need to be prescribed by physicians. A meta-analysis was conducted to quantitatively evaluate the published evidence on the efficacy of laxatives in constipation. We found that large, well-controlled, published studies whose data were comparable were lacking. Of 250 articles, 35 met the inclusion criteria but only 11 yielded usable data (N = 375 patients on laxatives, 174 on placebo). There was an effect of laxatives on stool frequency (mean increase 1.9 stools per week) and stool weight (mean increase 476 g) but this was not clearly distinguishable from that of placebo therapies (1 stool and 434 g, respectively) in studies up to 4 weeks in duration. Similarly, studies of 5–12 weeks yielded no differences overall. These results cannot definitively rule out laxatives as an effective treatment, due to the poor published evidence. Better evidence is required to justify the continued expenditure of funds on laxatives by both patients and formularies.  相似文献   
43.
The solubility and heat stability of surfactants are the prerequisites for their oilfield applications. Most commercial surfactants undergo hydrolysis at high temperature and prolonged heating at 40 °C or above leads to decomposition. In this report, three cationic poly(ethylene oxide) gemini surfactants (GSs) containing flexible and rigid spacers were synthesized for oilfield applications. The chemical structures of the GSs were elucidated with the aid of 13C NMR, 1H NMR, FT-IR, and MALDI-TOF MS. The GSs exhibit pronounced solubility in deionized water, seawater, and formation brine and no cloudiness, phase separation, or precipitation were detected after keeping GS solutions in an oven at 90 °C for three weeks. According to thermal gravimetric analysis, the degradation temperature of all the GSs was above 240 °C, which is higher than the existing oilfield temperature (≥90 °C). The critical micelle concentration (CMC) of the synthesized GSs decreases upon increasing the temperature. Additionally, CMC values were observed to increase even further with increasing salinity. The low CMC values of gemini surfactants containing a flexible structure indicate that they create a more closely packed micelle structure compared with gemini surfactants with a rigid structure. The distinct surface and thermal features of the synthesized GSs reveal them to be appropriate materials for high salinity and elevated temperature reservoirs.

Synthesis of new cationic poly(ethylene oxide) gemini surfactants containing flexible and rigid spacer groups to tolerate harsh reservoir condition.  相似文献   
44.
The present article reports a case involving an immunocompetent, previously well child who, despite two previous doses of inactivated poliovirus vaccine, developed severe flaccid paralysis consistent with polio after receiving oral polio vaccine.  相似文献   
45.

Background

Smaller studies have evaluated SLC6A4 5-HTTLPR and GNβ3 825C>T polymorphisms in IBS, and interactions between 5-HTT LPR with life events have been reported in the psychiatric literature, but gene–environment studies in IBS are lacking.

Aims

The purpose of this study was to assess the association of two polymorphisms with IBS and age of onset, and whether there are gene–environment interactions with IBS.

Methods

Outpatients with IBS and controls completed a validated questionnaire and provided blood for DNA. Comparisons of genotype/allele frequencies between cases and controls were performed with logistic regression. Linear regression was used to evaluate the association between the variants and age of onset. Environmental variables tested included abuse, parental alcohol abuse, parental psychiatric disorders, and gastrointestinal infections.

Results

Genotyping was performed in 385 cases and 262 controls with median age of 50 years (range, 18.0–70.0) and 498 (77 %) females. The IBS subtype distribution among cases was: 102 (26 %) D-IBS, 40 (10 %) C-IBS, 125 (32 %) M-IBS, 118 (31 %) other. No association was observed between IBS or age of onset and both variants. Significant interactions were observed between GI infection and the GNβ3 825T allele. For those reporting gastrointestinal infection, the OR for IBS was 3.9 (95 % CI 1.2–12.7) whereas the OR was 0.86 (95 % CI 0.65–1.13) for those without prior infection.

Conclusions

There was a significant interaction between the GNβ3 polymorphism and infection in the development of IBS, suggesting that its etiology is the result of a combination of specific genetic and environmental risk factors.  相似文献   
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48.
Frailty is a known risk factor for those aged 65 and over, and its prevalence increases with age. Definitions of frailty vary widely, and prevalence estimates are affected by the way frailty is defined. Systematic reviews have yet to examine the literature on the association between definitions of frailty and mortality.We examined the definitions and prevalence of frailty and its association with survival in older community-dwelling adults. We conducted a systematic review of observational population-based studies published in English. We calculated pooled prevalence of frailty with a random effects model.We identified 24 population-based studies that examined frailty in community-dwelling older adults. The pooled prevalence was 14% when frailty was defined as a phenotype exhibiting three or more of the following: weight loss, fatigue/exhaustion, weakness, low physical activity/slowness, and mobility impairment. The pooled prevalence was 24% when frailty was defined by accumulation of deficits indices that included up to 75 diseases and impairments. The prevalence of frailty increased with age and was greater in women and in African Americans. Frailty in older adults was associated with poor survival with a dose–responsive reduction in survival per increasing number of frailty criteria. Taking into account population prevalence and multivariate adjusted relative risks, we estimated that 3–5% of deaths among older adults could be delayed if frailty was prevented.Frailty is a prevalent and important geriatric syndrome associated with decreased survival. Geriatric assessment of frailty provides clinically important information about functional status and survival of older adults.  相似文献   
49.
Complex thoraco-abdominal wall defects following tumor resection create a unique reconstructive challenge, which centers on anatomically re-establishing the thoracic and abdominal compartments to prevent visceral herniation. Autologous tissue may not be available or adequate to reconstruct these defects; therefore, the use of alternative options, such as non-autologous material, is often necessary. To our knowledge, very little has been described about the use of biologic mesh for the reconstruction of large thoracic defects. We present a review of the literature and present a novel approach to address a difficult defect with the use of cross-linked porcine dermal collagen (Permacol) to bridge a thoraco-abdominal defect while stabilizing the diaphragm. Level of Evidence: Level V, therapeutic study.  相似文献   
50.
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