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31.
We have evaluated the fibrinogen/fibrin fragment E antigen assay as a diagnostic test in patients with clinically suspected venous thrombosis by comparing the results of this assay with venography in 272 patients. The result of the fragment E antigen assay was elevated in 79 of 80 patients with positive venograms for recent venous thrombosis (sensitivity 99%) and within the normal range in 161 of 192 patients with normal venograms (specificity 84%). The fragment E assay was also evaluated in 130 medical and surgical controls without evidence of venous thrombosis by leg scanning and the test was found to be relatively nonspecific. However, in the patient group under study, a correct clinical diagnosis of no thrombosis, based on a normal fragment E result, was made in 161 of 162 cases (negative predictive value of 99%). Therefore, a normal test result effectively excludes a diagnosis of venous thrombosis in clinically symptomatic patients. The assay, as currently performed, is technically demanding and takes 24 hr to complete. Therefore, it will have to be simplified before it can be applied to clinical practice.  相似文献   
32.
Cirrhosis contributes significantly to morbidity and mortality worldwide. Infections in patients with cirrhosis are common and significantly impact health-related quality of life. As our understanding of immune dysfunction associated with cirrhosis grows and as rates of drug-resistant organisms increase, the management of infections in cirrhosis has become increasingly nuanced. In this review, we discuss the current understanding of cirrhosis-associated immune deficiency, review the most common infections in patients with cirrhosis, and highlight techniques for the general clinician in the prevention and treatment of infections in this high-risk population.  相似文献   
33.
The digoxin-quinidine interaction was studied in nine healthy human subjects aged 26 to 31 years. A single oral dose (400 mg) of quinidine sulfate administered to subjects taking digoxin resulted in a mean (± standard error of the mean) increase within 1 to 6 hours in the serum digoxin concentration of 0.12 ± 0.01 ng/ml (p <0.0001), an increase of 21 percent. Continued quinidine administration for 24 hours resulted in a 59 percent increase in the mean serum digoxin concentration from 0.68 ± 0.04 to 1.04 ± 0.06 ng/ml (alpha = 0.05). At the same time, however, systolic time intervals demonstrated a lengthening of the mean left ventricular ejection time index from 406 ± 4 to 419 ± 2 ms (alpha = 0.05) and the mean Q?S2 Index from 524 ± 6 to 532 ± 7 ms (difference not significant [NS]). When compared with the shortening of these intervals predicted from the digoxin dose-response curve if digoxin were the only variable, the lengthening actually observed for both intervals was highly significant. The negative inotropic effect of quinidine administration alone was assessed with systolic time intervals in four subjects. The left ventricular ejection time index lengthened from 419 ± 3 to 425 ± 6 ms (NS) and the Q?S2 index from 541 ± 6 to 550 ± 7 ms (NS). Therefore, the lengthening of these intervals in subjects taking digitalis after the addition of quinidine represents more than just the negative inotropic effect of quinidine, and occurs despite the increase in serum digoxin concentration.The results of this study support the view that quinidine displaces digoxin from tissue-binding sites as a major mechanism of the interaction. Furthermore, it appears that quinidine may specifically displace digoxin from cardiac-binding sites. These results raise important questions concerning the recommendation to reduce the maintenance digoxin dose when concomitant quinidine therapy is initiated.  相似文献   
34.
A non-human primate antiserum was prepared to acute lymphoblastic leukemia of T-cell phenotype (T-ALL) and, after absorptions with normal blood elements, reacted by immunofluorescence and microcytotoxicity to all the T-ALL tested. In addition, the antiserum reacted with cells from about 70% of the common ALL studied and immunoprecipitated the common ALL antigen of 100,000 daltons. However, when the anti-T-ALL serum was absorbed with with lymphoblasts from common ALL, it failed to react with common ALL lymphoblasts, yet reacted significantly with cells from patients with T-ALL phenotype and defined a 100,000-dalton membrane component not found on common ALL lymphoblasts. In addition, sequential immunoprecipitation of 125I-labeled T-ALL membranes by anti- common-ALL serum followed by anti-T-ALL serum detected the T-ALL membrane component of 100,000 daltons that was not found on common ALL. Thus, our results demonstrate the presence of of a unique human T-ALL antigen present on all T-ALL distinct from the common ALL antigen.  相似文献   
35.
作为标准化的非手术治疗,诱导化疗(ICT)在治疗局部晚期头颈鳞癌已有几十年的历史,但是关于其作用尚存争议。同期放化疗(CRT)是目前标准化的非手术治疗,然而由于ICT能够使肿瘤体积缩小,提高放疗的可行性,改善患者对放疗的耐受力,增加放疗后器官功能保留的可能性及降低远处转移率。所以,对ICT的研究从未停止。该文对近期随机试验进行回顾分析,与手术或单独CRT比较,评估ICT中紫杉醇的价值。Meta分析比较ICT中紫杉醇和顺铂及5氟尿嘧啶的作用。之前的随机试验中,并没有ICT提高生存率的报道。但  相似文献   
36.
37.
Modern population based oral health management requires a complete understanding of the impact of disease in order to provide efficient and effective oral health care and guidance. Periodontitis is an important cause of tooth loss and has been shown to be associated with a number of systemic conditions. The impact of oral conditions and disorders on quality of life has been extensively studied. However, the impact of periodontitis on quality of life has received less attention. This review summarizes the literature on the impact of periodontitis on oral health‐related quality of life (OHRQoL). Relevant publications were identified after searching the MEDLINE and EMBASE electronic databases. Screening of titles and abstracts and data extraction was conducted. Only observational studies were included in this review. Most of the reviewed studies reported a negative impact of periodontitis on OHRQoL. However, the reporting standards varied across studies. Moreover, most of the studies were conducted in developed countries.  相似文献   
38.
In previous studies, we have reported that standard heparin (SH) was cleared by two mechanisms, a saturable mechanism which predominated at low doses (<100 anti-factor Xa U/kg) and a non-saturable mechanism which predominated at higher doses, when the first mechanism became saturated. In this study, we examined the importance of these two mechanisms in the disappearance of a low molecular weight heparin fraction (LMWH) (CY 216), by comparing the pharmacokinetics and the pharmacodyna-mics of a wide range of doses of SH and CY 216 (1.5 to 500 anti-factor Xa U/kg) Pharmacokinetics was measured as the disappearance of 125I-radiolabelled SH or CY 216. Pharmacodynamics was measured as the disappearance of the anti-factor Xa activity of SH and CY 216. We found that the saturable mechanism contributed little to the disappearance of CY 216 and that it was cleared predominantly by the non-saturable mechanism at all doses tested. Thus, at low doses (<100 anti-factor Xa U/kg), SH was cleared more rapidly than CY 216, whereas at higher doses, CY 216 was cleared more rapidly than SH. We conclude that the mechanism of disappearance of LMWH's differ significantly from those of SH, and that this difference may explain the apparent prolonged anticoagulant activity of LMWH's within the therapeutic range doses.  相似文献   
39.

Background

Because neprilysin is involved in the degradation of amyloid-beta, there is concern that the angiotensin-neprilysin inhibitor sacubitril-valsartan could increase the risk for dementia.

Methods

We analyzed adverse event cases submitted to the Food and Drug Administration Adverse Event Report System from July 2015 to March 2017. Cognition- and dementia-related adverse event cases were defined with the use of broad and narrow structured medical queries.

Results

During the period evaluated, 9,004 adverse event reports (out of a total of 2,249,479) involved the use of sacubitril-valsartan. Based on the broad definition, sacubitril-valsartan was associated with cognition- and dementia-related adverse events in 459 reports (5.1%), but this was lower than the proportion of these reports among other medications (6.6%, reporting odds ratio [ROR] 0.72, 95% confidence interval [CI] 0.65–0.79). Restricting the comparison to cases with age >60 years and with the use of a comparator group with heart failure resulted in no association between sacubitril-valsartan and dementia-related adverse events, with the use of both the broad and the narrow definitions (ROR 0.87, 95% CI 0.76–1.02, and ROR 1.06, 95% CI 0.4–3.16, respectively).

Conclusion

Sacubitril-valsartan is not associated with a disproportionately high rate of short-term dementia-related adverse effect reports. Long-term studies assessing cognitive outcomes are required to better establish the medication's cognition effects.  相似文献   
40.
BACKGROUND: Patients who have a first episode of venous thromboembolism in the absence of known risk factors for thrombosis (idiopathic thrombosis) are often treated with anticoagulant therapy for three months. Such patients may benefit from longer treatment, however, because they appear to have an increased risk of recurrence after anticoagulant therapy is stopped. METHODS: In this double-blind study, we randomly assigned patients who had completed 3 months of anticoagulant therapy for a first episode of idiopathic venous thromboembolism to continue receiving warfarin, with the dose adjusted to achieve an international normalized ratio of 2.0 to 3.0, or to receive placebo for a further 24 months. Our goal was to determine the effects of extended anticoagulant therapy on rates of recurrent symptomatic venous thromboembolism and bleeding. RESULTS: A prespecified interim analysis of efficacy led to the early termination of the trial after 162 patients had been enrolled and followed for an average of 10 months. Of 83 patients assigned to continue to receive placebo, 17 had a recurrent episode of venous thromboembolism (27.4 percent per patient-year), as compared with 1 of 79 patients assigned to receive warfarin (1.3 percent per patient-year, P<0.001). Warfarin resulted in a 95 percent reduction in the risk of recurrent venous thromboembolism (95 percent confidence interval, 63 to 99 percent). Three patients assigned to the warfarin group had nonfatal major bleeding (two had gastrointestinal bleeding and one genitourinary bleeding), as compared with none of those assigned to the placebo group (3.8 vs. 0 percent per patient-year, P=0.09). CONCLUSIONS: Patients with a first episode of idiopathic venous thromboembolism should be treated with anticoagulant agents for longer than three months.  相似文献   
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