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991.
Angiographic and clinical predictors of acute closure after native vessel coronary angioplasty 总被引:7,自引:0,他引:7
S G Ellis G S Roubin S B King J S Douglas W S Weintraub R G Thomas W R Cox 《Circulation》1988,77(2):372-379
To determine predictors of acute coronary closure after PTCA performed with steerable catheter systems, we compared 140 procedures complicated by acute closure and 311 representative successful attempts from 4,772 procedures performed between April 1982 and March 1986. Sixteen clinical, 35 angiographic, and seven procedural variables were analyzed. Multivariate analysis found seven independent preprocedural factors related to closure: stenosis length of 2 or more luminal diameters, female gender, stenosis at a bend point of 45 degrees or more, stenosis at a branch point, stenosis-associated thrombus (filling defect or staining), other stenoses in the same vessel, and multivessel disease. In addition, four procedural factors were found to be associated with closure by univariate analysis: post-PTCA percent stenosis (p less than .001), intimal tear or dissection (p less than .001), use of prolonged heparin infusion (p less than .001), and post-PTCA gradient of 20 mm Hg or more (p = .004). Multivariate analysis of both preprocedural and procedural variables found six factors independently related to closure: post-PTCA percent stenosis, dissection, prolonged post-PTCA use of heparin, branch point location, fixed bend point location, and other stenoses in the vessel dilated. The risk of coronary closure after PTCA has many determinants. While an estimation of risk can be made before performing PTCA, the most powerful predictors of closure can only be assessed during the procedure itself. 相似文献
992.
Dr. Jorge E. Valenzuela MD Robert B. Strecker MD Adrian P. Douglas MD 《Digestive diseases and sciences》1981,26(5):433-437
The efficacy of tiotidine, a new H2-receptor antagonist, in reducing nocturnal acid secretion of duodenal ulcer patients (N=12, ages 21–60 years) was investigated. Different doses of tiotidine, 25, 50, 100, and 150 mg or placebo, were given as a single oral dose and acid secretion collected overnight. Tiotidine produced a significant, prolonged, and dose-related reduction of the nocturnal acid secretion without important side effects. The inhibition of cumulative H+ secretion after 25, 50, 100, and 150 mg tiotidine was 80, 89, 96, and 98% of that observed after placebo, while 300 mg of cimetidine caused an 87% inhibition. Compared to cimetidine, tiotidine appears to be approximately eight times more potent on a molar basis than cimetidine as an inhibitor of acid secretion, and the tiotidine effect is more prolonged. This strong and safe H2-receptor antagonist may be an important addition to the treatment of acid hypersecretory states. 相似文献
993.
Purpose of Review
We provide an overview of our current understanding of combination lipid-lowering therapies intended for dyslipidemia treatment and cardiovascular disease prevention. First, we analyze recent statin and non-statin combination therapy guidelines and clinical studies since the publication of 2013 American College of Cardiology Cholesterol Guidelines. Second, we examine the clinical utility of non-statin agents alone and in combination in terms of LDL-C lowering and ASCVD risk reduction.Recent Findings
Medical societies, including the American College of Cardiology (ACC), National Lipid Association (NLA), and American Association of Clinical Endocrinologists (AACE), have released guidelines to address the appropriate use of non-statin therapies. The guidelines incorporated new evidence, including the IMPROVE-IT and FOURIER clinical trials, which demonstrate that the combination of statin therapy with other non-statin agents such as ezetimibe and PCSK9 inhibitors has a significant clinical benefit. Increasing evidence that aggressive low-density lipoprotein cholesterol (LDL-C) lowering leads to lower cardiovascular disease risk supports the need for continued exploration of the role of combination lipid-lowering therapies.Summary
A review of guidelines and clinical trials evaluating non-statin agents illuminates the growing base of evidence and expert opinion supporting the use of combination lipid-lowering therapies. While the majority of clinical trial data utilizes dyslipidemia monotherapy, especially statins, combination therapies represent an opportunity for individualized, patient-centered approach to LDL-C lowering and atherosclerotic cardiovascular disease (ASCVD) risk reduction. The overview provides a perspective on lipid management intended for clinicians who seek additional information and guidance on the use of combination therapies.994.
Nelson HD Rizzo J Harris E Cauley J Ensrud K Bauer DC Orwoll E;Study of Osteoporotic Fractures Research Group 《Archives of internal medicine》2002,162(20):2278-2284
BACKGROUND: Previous studies demonstrate that postmenopausal women who use estrogen are somewhat protected from bone loss and fractures compared with nonusers, but the extent to which estrogen users remain at risk for osteoporosis and fractures is uncertain. OBJECTIVE: To determine long-term probabilities for incident fractures among postmenopausal estrogen users. METHODS: We examined data from the Study of Osteoporotic Fractures, a prospective cohort study with 10 years of follow-up (1986-1999). This cohort includes 8816 women 65 years and older from community settings in 4 areas of the United States. MAIN OUTCOME MEASURES: Hip, wrist, vertebral, and nonvertebral fractures. RESULTS: At baseline, using criteria developed by the World Health Organization, 40% of continuous estrogen users were osteopenic and 13% were osteoporotic at the hip or spine. Although women currently using estrogen lost less bone density than past users or those who never used estrogen, all user groups on average lost bone from the hip and calcaneus. During 10 years of observation, the adjusted probability of nonvertebral fractures was 19.6% for continuous estrogen users, similar to current partial users and lower than past users and those who never used estrogen (P<.05). These comparisons were similar for hip, wrist, and vertebral fractures. CONCLUSIONS: Although estrogen use is associated with reduced prevalence of low bone density, less bone loss, and lower probabilities for fractures, osteoporosis and fractures are common in older women who used estrogen continuously since menopause. Estrogen users should be considered in strategies designed to detect, prevent, and treat osteoporosis. 相似文献
995.
Impact of HIV infection on meningitis in Harare, Zimbabwe: a prospective study of 406 predominantly adult patients 总被引:6,自引:0,他引:6
Hakim JG Gangaidzo IT Heyderman RS Mielke J Mushangi E Taziwa A Robertson VJ Musvaire P Mason PR 《AIDS (London, England)》2000,14(10):1401-1407
OBJECTIVE: To determine the causative organisms and characteristics of patients presenting with features of meningitis. DESIGN: A prospective cross-sectional study. SETTING: Two tertiary university-affiliated hospitals in Harare, Zimbabwe. PATIENTS: Four-hundred and six patients clinically suspected to have meningitis. MAIN OUTCOME MEASURES: Causative organisms of meningitis; clinical and cerebrospinal fluid characteristics. RESULTS: Four-hundred and six predominantly adult (95% were aged > or = 18 years) patients were suspected to have meningitis. Of the 200 patients confirmed to have meningitis, 89 (45%) had cryptococcal meningitis (CM), 54 (27%) had mononuclear meningitis (MM), 31 (16%) had pyogenic meningitis (PM), 24 (12%) had tuberculous meningitis (TBM) and 2 (1%) had undefined meningitis. HIV seropositivity was 100% in CM, 83% in MM, 81% in PM and 88% in TBM patients. In-hospital mortality rate was 38.8% for CM, 34.9% for MM, 68% for PM and 66.7% for TBM. HIV seropositivity was 80% in the 206 patients not found to have meningitis. CONCLUSIONS: All patients suspected to have meningitis had a high HIV sero positivity irrespective of whether they were later confirmed to have meningitis or not. CM was the most common type of meningitis seen. In-hospital mortality was high irrespective of the cause of meningitis. 相似文献
996.
Central memory self/tumor-reactive CD8+ T cells confer superior antitumor immunity compared with effector memory T cells 总被引:8,自引:0,他引:8 下载免费PDF全文
Klebanoff CA Gattinoni L Torabi-Parizi P Kerstann K Cardones AR Finkelstein SE Palmer DC Antony PA Hwang ST Rosenberg SA Waldmann TA Restifo NP 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(27):9571-9576
Central memory CD8+ T cells (T(CM)) and effector memory CD8+ T cells (T(EM)) are found in humans and mice; however, their relative contributions to host immunity have only recently been examined in vivo. Further, the ability of T(CM) to treat an established tumor or infection has yet to be evaluated. To address the therapeutic potential of different tumor-reactive CD8+ T cell memory subsets, we used an established model for the in vitro generation of T(CM) and T(EM) by using IL-15 and IL-2, respectively. Adoptively transferred T(CM) exhibited a potent in vivo recall response when combined with tumor-antigen vaccination and exogenous IL-2, leading to the eradication of large established tumors. By contrast, T(EM) were far less effective on a per-cell basis. Microarray analysis revealed that the signature of highly in vivo effective antitumor T cells included the overexpression of genes responsible for trafficking to secondary lymphoid tissues. This gene expression profile correctly predicted the in vitro and in vivo lymphoid-homing attributes of tumor-reactive T cells. Furthermore, we found that homing to secondary lymphoid tissue is required for optimal tumor treatment. Our findings indicated that highly in vivo effective antitumor T cells were those that initially targeted secondary lymphoid tissue, rather than tumor sites, as had previously been postulated. Thus, tumor-reactive CD8+ T cell populations with the phenotypic and functional attributes of T(CM) may be superior to T(EM)/effector T cells for adoptive immunotherapies using concomitant tumor-antigen vaccination. 相似文献
997.
998.
Relationship of systolic BP to obstructive sleep apnea in patients with heart failure 总被引:10,自引:0,他引:10
STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is an independent risk factor for hypertension in the general population. Hypertension is, in turn, an important risk factor for the development and progression of congestive heart failure (CHF). Our objective was to determine whether OSA would be associated with elevated daytime BP in medically treated patients with CHF. DESIGN: Cross-sectional study. SETTING: Tertiary care, university-affiliated sleep disorders and heart failure clinics. PATIENTS: Three hundred one consecutive patients with CHF. MEASUREMENTS AND RESULTS: We measured daytime BP and performed overnight sleep studies to assess for the presence of OSA. Among these patients, OSA was present in 121 patients (40%) and their systolic BP was significantly higher than in patients without OSA. Patients with OSA were 2.89 times (95% confidence interval, 1.25 to 6.73) more likely to have systolic hypertension (ie, BP > or = 140 mm Hg) than those without OSA after controlling for other risk factors, including obesity. The degree of systolic BP elevation was directly related to the frequency of obstructive apneas and hypopneas. CONCLUSIONS: In medically treated patients with CHF, daytime systolic BP and the prevalence of systolic hypertension are significantly increased in patients with OSA, compared to those without OSA, independent of other potentially confounding factors. OSA may therefore have contributed to the presence of systolic hypertension in some of these patients. 相似文献
999.
Dieterich DT Wasserman R Bräu N Hassanein TI Bini EJ Bowers PJ Sulkowski MS 《The American journal of gastroenterology》2003,98(11):2491-2499
OBJECTIVE: The aim of this study was to determine the efficacy of epoetin alfa in alleviating anemia and minimizing ribavirin (RBV) dose reductions in patients with chronic hepatitis C virus (HCV) infection receiving combination RBV/interferon alfa (IFN) therapy. METHODS: HCV-infected patients who had Hb levels of 12 g/dl or less during the first 24 wk of combination RBV/IFN therapy (n=64) were randomized to treatment with epoetin alfa (40,000 units) s.c. q.w. or to standard of care (SOC) for anemia management (RBV dose reduction or discontinuation, transfusions). Primary and secondary efficacy endpoints were changes in Hb level and RBV dosage, respectively, from baseline to week 16 of epoetin alfa therapy.Based on intent-to-treat analysis, the mean changes from baseline Hb levels at week 16 were +2.8 g/dl for epoetin alfa versus +0.4 g/dl for SOC (p<0.0001), and the mean changes in RBV dosage were -34 mg/day for epoetin alfa versus -146 mg/day (p=0.060) for SOC. The mean Hb level at week 16 in the epoetin alfa group (13.8 g/dl) was significantly (p<0.0001) higher than that of the SOC group (11.4 g/dl). At week 4 and subsequently, significantly more patients in the epoetin alfa group did not have RBV dosage reductions (p<0.011). At study end, 83% of epoetin alfa-treated patients maintained RBV dosages of at least 800 mg/day, compared with 54% of patients receiving SOC (p=0.022). Epoetin alfa was well tolerated. CONCLUSIONS: In anemic HCV-infected patients treated with RBV/IFN, epoetin alfa increases Hb levels and maintains RBV dosing. Based on these results, epoetin alfa seems to be promising in the treatment of HCV treatment-related anemia. Further research is warranted to determine the potential impact on outcomes, including quality of life and sustained viral response rate. 相似文献
1000.
Kes Aslihan Ogwang Sheila Pande Rohini Prabha Douglas Zayid Karuga Robinson Odhiambo Frank O Laserson Kayla Schaffer Kathleen 《Reproductive health》2015,13(1):1-7
This study explores the consequences of a maternal death to households in rural Western Kenya focusing particularly on the immediate financial and economic impacts. Between September 2011 and March 2013 all households in the study area with a maternal death were surveyed. Data were collected on the demographic characteristics of the deceased woman; household socio-economic status; a history of the pregnancy and health care access and utilization; and disruption to household functioning due to the maternal death. These data were supplemented by in-depth and focus group discussions. The health service utilization costs associated with maternal deaths were significantly higher, due to more frequent service utilization as well as due to the higher cost of each visit suggesting more involved treatments and interventions were sought with these women. The already high costs incurred by cases during pregnancy were further increased during delivery and postpartum mainly a result of higher facility-based fees and expenses. Households who experienced a maternal death spent about one-third of their annual per capita consumption expenditure on healthcare access and use as opposed to at most 12% among households who had a health pregnancy and delivery. Funeral costs were often higher than the healthcare costs and altogether forced households to dis-save, liquidate assets and borrow money. What is more, the surviving members of the households had significant redistribution of labor and responsibilities to make up for the lost contributions of the deceased women. Kenya is in the process of instituting free maternity services in all public facilities. Effectively implemented, this policy can lift a major economic burden experienced by a very large number of household who seek maternal health services which can be catastrophic in complicated cases that result in maternal death. There needs to be further emphasis on insurance schemes that can support households through catastrophic health spending. 相似文献