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OBJECTIVE: Existing literature indicates that the mortality rate with each variceal bleeding episode is 30-50%. Over the past 2 decades, there have been significant developments in the management of variceal bleeding. The effect of these developments on the natural history of variceal bleeding is unclear. Therefore, a retrospective, multicenter study was conducted to define the outcomes of variceal bleeding and to describe the patterns of current practice in the management of variceal bleeding. METHODS: All patients with documented variceal bleeding hospitalized at four large county hospitals from January 1, 1997, to June 30, 2000, were included. Study outcomes were in-hospital, 6-wk, and overall mortality, rate of rebleeding, transfusion requirement, and length of stay. After discharge, patients were followed until death or study closure date, on June 30, 2000. RESULTS: A total of 231 subjects were included, and their in-hospital, 6-wk, and overall mortality rates were 14.2%, 17.5%, and 33.5%, respectively. The frequency of rebleeding during follow-up was 29%. Median length of total hospital stay was 8 days (0-34 days). Median number of packed red cell units transfused was 4 U (0-60 U). Upper endoscopy was performed in 95% of patients within 24 h, and endoscopic therapy was done in all but eight patients (ligation 64%, sclerotherapy 33%). Octreotide was administered in 74% of the patients. Portasystemic shunts were performed in 7.5% of the patients for controlling acute variceal bleeding. CONCLUSIONS: The mortality rate after variceal bleeding in this study was substantially lower than previously reported. This suggests that advances made in the management of variceal bleeding have improved outcomes after variceal bleeding.  相似文献   
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CONTEXT: Genetic aberration in phosphatidylinositol 3-kinase (PI3K)/AKT pathway has been detected in numerous and diverse human cancers. PIK3CA, which encodes for the catalytic subunit of p110alpha of PI3K, is amplified in some cases of papillary thyroid cancer (PTC). Mutations in the PIK3CA have also been identified in thyroid cancers and, although relatively common in anaplastic thyroid carcinoma, are uncommon in PTC. OBJECTIVE: The objective of the study was to investigate genetic alterations like PIK3CA gene mutation, PIK3CA amplification, RAS, and RAF mutations and to further explore the relationship of these genetic alterations with various clinicopathological characteristics in Middle Eastern PTC. DESIGN: We used the fluorescence in situ hybridization technique for analysis of PIK3CA amplification from 536 PTC cases, and selected amplified samples were further validated by real-time quantitative PCR. Mutation analysis was done by direct DNA sequencing of PIK3CA, N2-RAS, and BRAF genes. RESULTS: PIK3CA amplification was seen in 265 of 499 PTC cases analyzed (53.1%); PIK3CA gene mutations in four of 207 PTC (1.9%); N2-RAS mutations in 16 of 265 PTC (6%); and BRAF mutations in 153 of 296 PTC (51.7%). N-RAS mutations were-associated with an early stage (P = 0.0465) and lower incidence of extrathyroidal extension (P = 0.027), whereas BRAF mutations were-associated with metastasis (P = 0.0274) and poor disease-free survival (P = 0.0121) in PTCs. CONCLUSION: A higher incidence of PIK3CA alterations and the possible synergistic effect of PIK3CA alterations and BRAF mutations suggest their major role in Middle Eastern PTC tumorigenesis and argue for therapeutic targeting of PI3K/AKT and MAPK pathways.  相似文献   
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BackgroundCardiovascular disease is the leading cause of death in India. Our aim is to study the clinical, epidemiological profile and in-hospital outcomes of patients presenting with acute coronary syndrome.MethodsWe did a prospective single center observational study of the 1203 patients presenting with ACS to a tertiary referral center in North India over a period of one year (July 2018–June 2019).ResultsThe mean age of study population was 58.4 ± 12.5 years. STEMI and NSTE-ACS accounted for 69.9% and 31.1% respectively. 62.1% of our patients were from rural background. The median time to hospital admission was 600 min for STEMI patients, thrombolysis was performed in 52% of cases. Cardiogenic shock at presentation was noted in 18%. Coronary angiography and percutaneous coronary intervention were done in 1062 (88.3%) and 733 (60.9%) patients respectively. The overall in-hospital mortality was 7.6%. STEMI patients had higher mortality than NSTE-ACS (8.9% vs 4.5% p < 0.001). Female gender (OR?3.306 C.I. 1.87–5.845), severe MR (OR?4.65, C.I.?1.187–18.18), acute kidney injury (AKI) at admission (OR-5.15, C.I.?2.5–10.63), higher Killip class (class III/IV) (OR?3.378,C.I.?1.292–8.849), AF (OR?3.25, C.I.?1,18–8.92), complete heart block (CHB) (OR?4.44,C.I.?2.09–9.43) and right bundle branch block (RBBB) (OR?2.86, C.I.?1.2–6.8) were significant predictors of in hospital mortality.ConclusionsOur study represents the predominance of STEMI as the initial ACS presentation with a considerable delay in first medical contact and higher prevalence of cardiogenic shock (CS). STEMI patients had higher mortality. Female sex, severe MR, AKI, higher Killips class, AF, CHB, RBBB being predictors of high in-hospital mortality in ACS patients.  相似文献   
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Ce4+ and Zn2+ co-doped barium hexaferrites (BFO) have been synthesized via a citrate-nitrate autocombustion route. Phase purity has been confirmed by high resolution (HR) powder X-ray diffraction analysis. Rietveld refinement on HR-XRD data has been carried out to reveal the crystal structure, bond angles and bond lengths. High-resolution scanning electron microscope (HR-SEM) has been used to study the effect of Ce4+ and Zn2+ on microstructure. Magnetic behavior of co-doped barium hexaferrites in the low temperature regime, 2–300 K has been studied. Further, it has been explained on the basis of superexchange interactions and formation of Bloch walls due to the presence of imperfections in the doped samples. It has been found that BFO changes hard to soft magnetic behavior when the temperature is decreased from 300 K to 2 K. Moreover, doping of Ce4+ and Zn2+ at Fe3+ site also brings similar effects which strengthens with decreasing temperature.

Preparation of Ce–Zn substituted barium hexaferrites and investigation of their magnetic behavior in low temperature regime (2–300 K).  相似文献   
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Celiac disease (CeD) is a chronic gluten-induced enteropathy with plethoric manifestations. The typical manifestations of CeD such as chronic diarrhea and malabsorption are widely recognized, however, many patients have atypical manifestations like iron deficiency anemia, idiopathic short stature, hypertransaminesemia or infertility, etc. These patients often present to the primary care physicians and/or non-gastrointestinal specialties. However, due to a lack of awareness among the healthcare professionals about the various atypical manifestations, many patients are not screened for CeD. In this review, we have summarized the available literature about the prevalence of CeD in various gastrointestinal (chronic diarrhea) and non-gastrointestinal conditions (iron deficiency anemia, short stature, cryptogenic hypertransaminesemia, cryptogenic cirrhosis or idiopathic ataxia etc.) where the diagnosis of CeD should be con-sidered. In addition, we also discuss special scenarios where screening for CeD should be considered even in absence of symptoms such as patients with type 1 diabetes, Down’s syndrome, and first-degree relatives of patients with CeD. Further, we discuss the diagnostic performance and limitations of various screening tests for CeD such as IgA anti-tissue transglutaminase antibodies, anti-endomysial antibodies and anti-deamidated gliadin antibodies. Based on the current recommendations, we propose a diagnostic algorithm for patients with suspected CeD.  相似文献   
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Background and objectives: No studies have evaluated the relationship among spirituality, social support, and survival in patients with ESRD. This study assessed whether spirituality was an independent predictor of survival in dialysis patients with ESRD after controlling for age, diabetes, albumin, and social support.Design, setting, participants, & measurements: A total of 166 patients who had ESRD and were treated with hemodialysis completed questionnaires on psychosocial variables, quality of life, and religious and spiritual beliefs. The religious variables were categorized into three scores on a 0 to 20 scale (low to high levels): Spirituality, religious involvement, and religion as coping. Social support was assessed using the Multidimensional Scale for Perceived Social Support. Analyses were also performed including and excluding patients with HIV infection. Religious variables were categorized on the basis of means, medians, and tertiles.Results: In analyses that used religious variables, only the responses on the spirituality scale split at the mean were associated with survival. The association of other religious variables with survival did not reach significance. Social support correlated with spirituality, religion as coping, and religious involvement measures. Only social support and age were associated with survival when controlling for diabetes, albumin concentration, HIV infection, and spirituality.Conclusions: These data suggest that the effects of spirituality may be mediated by social support. Larger, multicenter, prospective studies that use well-validated tools to measure religiosity and spirituality are needed to determine whether there is an independent association of spirituality variables with survival in patients with ESRD.Relationships between spirituality and mortality have been investigated in medical populations but remain controversial (113). Variable associations have been found depending on definitions of spirituality and patient populations studied (111). Miller and Thoreson (12) explored nine different hypotheses regarding the relationship among religious beliefs, spirituality, and mortality. The only hypothesis that they found to be supported by persuasive evidence stated that “church/service attendance protects [only] healthy people against death.” Studies supporting a similar link in patients with chronic illnesses have also shown mixed results. Koenig et al. (14) evaluated approximately 4000 elderly patients to determine whether attendance at religious services during a 6-yr period was associated with survival. In adjusted analyses, there was a significantly lower mortality in patients who frequently attended church services.Many researchers have suggested a publication bias, whereby only the studies that indicate a significant relationship are published (13). Most studies cited the need for more research on the relationship between spirituality and mortality before any firm conclusions can be reached. In addition, the health dimensions of lack of belief have not been well explored.There also exists considerable debate on how to operationalize religiosity and spirituality. Whereas the first term often is associated with participation in social institutions and adherence to specific beliefs and practices, the latter is a broader term that typically pertains to life''s vital qualities and an overall broad belief in the immaterial features of life (12). Spirituality relates to transcendent values and relationships and the way people find meaning, purpose, and hope in life and in the midst of suffering (15). A person may be spiritual and not religiously observant or observe rituals without a spiritual focus.Few studies have specifically evaluated the potential association between spirituality and survival in patients with ESRD (16,17). We (18) previously showed that religious and spiritual beliefs are associated with decreased perception of burden of illness, decreased depressive affect, increased perception of social support, and higher satisfaction with life and perception of quality of life in an urban, predominantly black ESRD population. We also found that a “spiritual beliefs scale” correlated with several quality-of-life measures in patients with ESRD (19). Even though many of these psychosocial measures have been shown to be related to survival independently, no study to our knowledge has demonstrated a link between spirituality and survival in this population.We determined whether three variables related to spirituality, religious beliefs, and practices and faith (spirituality, religious involvement, and religion as a coping measure) were independently associated with survival in hemodialysis patients with ESRD. We then assessed the relationship between social support and survival, regardless of whether the spiritual variables were included in analyses. We hypothesized that spiritual variables would be associated with survival in patients with ESRD.  相似文献   
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Cardiovascular computed tomography (CCT) is a well-validated non-invasive imaging tool with an ever-expanding array of applications beyond the assessment of coronary artery disease. These include the evaluation of structural heart diseases, congenital heart diseases, peri-procedural electrophysiology applications, and the functional evaluation of ischemia. This breadth requires a robust and diverse training curriculum to ensure graduates of CCT training programs meet minimum competency standards for independent CCT interpretation. This statement from the Society of Cardiovascular Computed Tomography aims to supplement existing societal training guidelines by providing a curriculum and competency framework to inform the development of a comprehensive, integrated training experience for cardiology and radiology trainees in CCT.  相似文献   
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