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141.
Cigarette smoking and ulcerative colitis. A case control study   总被引:1,自引:0,他引:1  
In order to examine the relationship between cigarette smoking and ulcerative colitis (UC), we carried out a case-control study of smoking habits in 84 patients with UC and in two different types of controls: 84 taken from a hospital population and 84 from the general population, matched to the cases for age, sex, school education and social class. Non-smokers were found to have a greater UC risk than smokers in both internal controls (Odds ratio = 4.6, 95% CL = 1.8-11.7) and external controls (OR = 10, 95% CL = 3.6-26.9). There was a larger number of ex-smokers among patients with UC than among the controls. Evaluations at the time of disease onset also demonstrated that ex-smokers had a greater relative risk. Furthermore, 84% of the ex-smoker patients had stopped smoking before the onset of symptoms. Conditional multiple logistic regression with the introduction of alcohol (wine) and coffee as additional variable factors to age, sex, education and social class confirmed the independent protective effect of smoking on UC (OR for internal controls = 4.2, 95% CL = 1.7-10.2, OR for external controls = 5.7, 95% CL = 2.3-14.1). These results indicate that non-smokers and especially ex-smokers of cigarettes have a greater risk of UC, and thus confirm the results of other studies.  相似文献   
142.
Inhibins in childhood and puberty   总被引:7,自引:0,他引:7  
Inhibin is a heterodimeric glycoprotein that consists of an alpha-subunit linked to either a betaA subunit (inhibin A) or to a betaB subunit (inhibin B) and it exists in at least six different isoforms. These isoforms can not be measured separately by immunoassays. In boys, serum inhibin B levels change in concert with the increase in gonadotrophins. Associated with the postnatal activation of gonadotrophin secretion, the early inhibin B secretion is sustained until the age of 18-24 months; thereafter serum concentrations subside. In boys, between Tanner stages G1 and G2, serum inhibin B concentration again increases, but then plateaus. Inhibin A levels in human males are below the detection limit, but in girls, during the postnatal activation of gonadotrophin secretion, both serum inhibin A and inhibin B concentrations are measurable. Serum inhibin B levels correlate positively with age several years before the clinical onset of puberty, suggesting increasing follicular activity in late prepuberty. During female puberty, the inhibin B level increases from Tanner stage B1 through stage B3, suggesting high follicular activity before the development of ovulatory menstrual cycles, but serum inhibin A levels become measurable later in puberty, in agreement with the idea that inhibin A is mainly produced by the corpus luteum.  相似文献   
143.
Congenital coronary artery fistulas are important coronary artery anomalies. Bilateral coronary artery fistulas are very rare and coronary artery to left ventricular communications are even more infrequent. This report describes a patient with bilateral right and left coronary artery fistulas draining into a common channel and emptying into the left ventricular cavity.  相似文献   
144.
Leo A  Schraven B 《Platelets》2000,11(8):429-445
In multicellular organisms, the translation of externally applied signals into appropriate cellular responses is mediated by a multitude of complex intracellular signalling cascades. The accurate function of these signalling pathways is based on the sound interaction of proteins of different categories such as transmembrane receptors, protein kinases, protein phosphatases and g-proteins in three-dimensional signalling complexes. During the past 10 years it has became evident that a new class of proteins termed adaptor proteins is indispensable for the assembly of these intracellular signalling scaffolds. The primary function of adaptor proteins is to mediate protein-protein and protein-lipid interactions and thus to integrate receptor-mediated signals at the intracellular level and to couple signalling receptors to cytosolic signalling pathways. In order to perform this task, adapter proteins are equipped with particular protein-protein and/or protein-lipid interaction modules allowing them to communicate with other signalling proteins. While the essential function of adaptor proteins is clearly established in a variety of cell types (e.g. immune cells), the current knowledge about their role in platelet activation is still in the beginning. Numerous adaptor proteins have been shown to be expressed in platelets and many of them seem to be involved in the assembly of signalling complexes after engagement of platelet receptors such as the collagen receptor glycoprotein VI (GPVI), thrombin receptors, integrin receptors and the GP Ib receptor. This review will focus on the functional role of the most extensively studied adaptor proteins during platelet activation.  相似文献   
145.
Inflammation Research - Allergic rhinitis (AR) is characterized by typical symptoms that are dependent on inflammation. Poly-allergy is a frequent phenomenon. Phenotyping AR represents an...  相似文献   
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148.
Colovesical fistulae typically present with pneumaturia and/or fecaluria. Diverticulitis, inflammatory bowel disease, and malignancies of the colon are the commonest causes. The fistulous tract and adjacent organs are best demonstrated by contrast‐enhanced CT scan with rectal contrast or MRI. Biopsy at cystoscopy/colonoscopy is necessary for complete evaluation and treatment planning.  相似文献   
149.
Objectives

The objective of our study was to systematically review the evidence about synchronous colorectal cancer diagnosed with or without computed tomography colonography (CTC).

Materials and methods

Two systematic searches were performed (PubMed and EMBASE) for studies reporting the prevalence of synchronous colorectal cancer (CRC): one considering patients who underwent CTC and the another one considering patients who did not undergo CTC. A three-level analysis was performed to determine the prevalence of patients with synchronous CRC in both groups of studies. Heterogeneity was explored for multiple variables. Pooled prevalence and 95% confidence interval (CI) were calculated. A quality assessment (STROBE) was done for the studies.

Results

For CTC studies, among 2645 articles initially found, 21 including 1673 patients, published from 1997 to 2018, met the inclusion criteria. For non-CTC studies, among 6192 articles initially found, 27 including 111,873 patients published from 1974 to 2015 met the inclusion criteria. The pooled synchronous CRC prevalence was 5.7% (95% CI 4.7%–7.1%) for CTC studies, and 3.9% (95% CI 3.3%–4.4%) for non-CTC studies, with a significant difference (p = 0.004). A low heterogeneity was found for the CTC group (I2 = 10.3%), whereas a high heterogeneity was found in the non-CTC group of studies (I2 = 93.5%), and no significant explanatory variables were found. Of the 22 STROBE items, a mean of 18 (82%) was fulfilled by CTC studies, and a mean of 16 (73%) by non-CTC studies.

Conclusions

The prevalence of synchronous CRC was about 4–6%. The introduction of CTC is associated with a significant increase of the prevalence of synchronous CRCs.

  相似文献   
150.

Context

The need for hospice and palliative care is growing rapidly as the population increases and ages and as both hospice and palliative care become more accepted. Hospice and palliative medicine (HPM) is a relatively new physician specialty, currently training 325 new fellows annually. Given the time needed to increase the supply of specialty-trained physicians, it is important to assess future needs to guide planning for future training capacity.

Objectives

We modeled the need for and supply of specialist HPM physicians through the year 2040 to determine whether training capacity should continue growing.

Methods

To create a benchmark for need, we used a population-based approach to look at the current geographic distribution of the HPM physician supply. To model future supply, we calculated the annual change in current supply by adding newly trained physicians and subtracting physicians leaving the labor force.

Results

The current U.S. supply of HPM specialists is 13.35 per 100,000 adults 65 and older. This ratio varies greatly across the country. Using alternate assumptions for future supply and demand, we project that need in 2040 will range from 10,640 to almost 24,000 HPM specialist physicians. Supply will range from 8100 to 19,000.

Conclusion

Current training capacity is insufficient to keep up with population growth and demand for services. HPM fellowships would need to grow from the current 325 graduates annually to between 500 and 600 per year by 2030 to assure sufficient physician workforce for hospice and palliative care services given current service provision patterns.  相似文献   
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