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81.
82.
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   
83.
OBJECTIVE: Nutcracker esophagus (NE) is defined as the presence of peristaltic contractions in which the average distal esophageal amplitude is greater than 180 mm Hg. The underlying mechanism responsible for these abnormalities is not known. The aim of this study was to test the hypothesis that NE might be caused by a defect in the inhibitory pathway controlling esophageal peristalsis. METHODS: Eight patients with NE (seven women, 1 man, mean age 50 yr) and eight age- and sex-matched normal volunteers (seven women, 1 man, mean age 48 yr) underwent a special protocol using three-channel (3, 8, and 16 cm above the lower esophageal sphincter) solid state esophageal manometry to evaluate deglutitive inhibition. Ten pairs of 5 ml of wet swallows were given at each of five different time intervals (30, 20, 15, 10, and 5 s). Pairs of swallows were spaced by 30 s, and different time intervals were spaced by 1 min. Tracings were recorded using a computer program and blindly automatically analyzed for both amplitude and duration of the contraction separately for the first and second swallow of each pair. Presence of deglutitive inhibition or muscle refractoriness was assessed according to interactions between the first and second swallow of the pair. Results were found abnormal when larger than the mean percent variation of the second and first swallow calculated for the 30-s interval, considered as baseline for each participant. Statistics included paired and nonpaired nonparametrical comparisons as appropriate. RESULTS: The median amplitude for the NE was 202 mm Hg (range 186-376) and for the controls was 118 mm Hg (range 64-167) (p = 0.0002). The median duration in the NE group was 5.1 s (range 4-9.3) versus 4.1 (range 3.3-5.0) for the controls (p = 0.02). The percent variation in duration (p = 0.31), amplitude (p = 0.42), and propagation velocity of the peristaltic waves (p = 0.69) did not differ between the control and NE groups. Peristalsis frequency dropped at the 5-s interval for both studied groups (p = 0.84). CONCLUSION: Central and local inhibitory mechanisms induced by closely timed swallows are preserved in the NE and do not explain the mechanism of the high amplitude and long duration contractions.  相似文献   
84.
Amyloidosis is a disease resulting from extracellular deposition of fibrillar protein in various organs. AA amyloidosis may complicate chronic inflammatory diseases, chronic infections and another chronic diseases. We review 31 patients (13 males and 18 females) with biopsy proven renal or rectal AA amyloidosis, referred to out hospital between january 1999 and november 2002. Renal failure was defined as serum creatinine > or = 1.5 mg/dl. Mean age was 58.4 +/- 15.7 years. The causes of AA amyloidosis were an underlying chronic rheumatologic disease (51.6%), chronic infection (41.9%) and a chronic inflammatory intestinal disorder (6.5%). Renal failure (RF) was detected in 20 patients (61.2%) and proteinuria and hematuria were found in 90.3% and 45.5 respectively. Proteinuria at diagnosis was 5.2 +/- 3.9 g/24 h and mean serum creatinine 3.5 +/- 3.7 mg/dl. Survival of patients without dialysis was 66.8 (51.1% RF, 90.9% non-RF) and 53.4% (38.2 RF, 77.9% non-RF) at 12 and 24 months respectively (p = 0.017). End-stage renal disease developed in 13 patients (41.9%). Ten patients were maintained on hemodialysis and 3 on CAD. Survival in dialysis at 6 and 12 months was 68.3% and 42.7% respectively. Fifteen patients died and the main causes of death were: infections (46.6) haemorrhagic complications (33.3%), cardiovascular events (13.3%) and cachexia (6.6%).  相似文献   
85.
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   
86.
87.
Background:Although non-ischemic troponin elevation is frequently seen in patients admitted to the emergency department (ED), consensus regarding its management is lacking.Objectives:This study aimed to characterize patients admitted to the ED with non-ischemic troponin elevation and to identify potential mortality predictors in this population.Methods:This retrospective observational study included ED patients with a positive troponin test result between June and July of 2015. Patients with a clinical diagnosis of acute coronary syndrome (ACS) were excluded. Data on patient demographics and clinical and laboratory variables were extracted from medical records. Follow-up data were obtained for 16 months or until death occurred. The statistical significance level was 5%.Results:Troponin elevation without ACS was found in 153 ED patients. The median (IQR) patient age was 78 (19) years, 80 (52.3%) were female and 59(38.6%) died during follow-up. The median (IQR) follow-up period was 477(316) days. Survivors were significantly younger 76 (24) vs. 84 (13) years; p=0.004) and featured a higher proportion of isolated troponin elevation (without creatine kinase or myoglobin elevation) in two consecutive evaluations: 48 (53.9%) vs. 8 (17.4%), p<0.001. Survivors also presented a lower rate of antiplatelet treatment and same-day hospitalization. In the multivariate logistic regression with adjustment for significant variables in the univariate analysis, isolated troponin elevation in two consecutive evaluations showed a hazard ratio= 0.43 (95%CI 0.17–0.96, p=0.039); hospitalization, previous antiplatelet treatment and age remained independently associated with mortality.Conclusions:Isolated troponin elevation in two consecutive measurements was a strong predictor of survival in ED patients with troponin elevation but without ACS.  相似文献   
88.
splenectomy is usually followed by a mild, symptomless thrombocytosis which reaches a peak at about the end of the second week and gradually subsides within 3 months (Evans, 1928; Doan, Curtis and Wiseman, 1935; Wollstein and Kreidel, 1936; Ek and Rayner, 1950; Welch and Dameshek, 1950; Sedgwick and Hume, 1960). Occasionally, however, post-splenectomy thrombocytosis persists (Rosenthal, 1925; Chesner, 1946; Mills and Lucia, 1949; Green, Conley, Ashburn and Peters, 1953; Merskey and Budtz-Olsen, 1953; Gelpi and Ende, 1958; Byrd and Cooper, 1961; Barry and Day, 1962; Hayes, Spurr, Hutaff and Sheets, 1963; Dacie, Grimes, Meisler, Steingold, Hemsted, Beaven and White, 1964; Grimes, Meisler and Dacie, 1964; Losowsky and Hall, 1965) and may be associated with thrombo-embolic complications (Rosenthal, 1925; Chesner, 1946; Mills and Lucia, 1949; Gelpi and Ende, 1958; Byrd and Cooper, 1961; Barry and Day, 1962; Hayes et al. , 1963). However, although per-sistent post-splenectomy thrombocytosis has thus been recognized for many years, the underlying cause is poorly understood and has seldom been discussed. A consideration of the mechanism of post-splenectomy thrombocytosis and its possible bearing on post-splenectomy thrombo-embolism forms the basis of this report.
The present findings, based on a study of patients with a variety of anaemias and haematologically normal controls, suggest that persistence of thrombosytosis after splenectomy can usually be predicted: this happens when anaemia continues after splenectomy in association with active haemopoiesis.  相似文献   
89.
ABM: To assess long-term effects of Helicobacter pylori (H pylori) eradication on antral G cell morphology and function in patients with and without duodenal ulcer (DU). METHODS: Consecutive dyspeptic patients referred to the endoscopy entered the study. Out of 39 H pylori positive patients, 8 had DU (Hpylori+DU) and 31 gastritis (Hpylori +G). Control groups consisted of 11 uninfected dyspeptic patients (CG1) and 7 healthy volunteers (CG2). Basal plasma gastrin (PGL), antral tissue gastrin concentrations (ATGC), immunohistochemical and electron microscopic characteristics of G cells were determined, prior to and 6 mo after therapy. RESULTS: We demonstrated elevated PGL in infected patients compared to uninfected controls prior to therapy. Elevated PGL were registered in all H pylori+patients (H pylori +DU: 106.78±22.72 pg/mL, H pylori+G: 74.95±15.63, CG1: 68.59±17.97, CG2: 39.24±5.59 pg/mL, P<0.01). Successful eradication (e) therapy in H pylori+patients lead to significant decrease in PGL (H pylori+DU:59.93±9.40 and H pylori+Ge: 42.36±10.28 pg/mL, P<0.001). ATGC at the beginning of the study were similar in infected and uninfected patients and eradication therapy lead to significant decrease in ATGC in H pylori+gastritis, but not in DU patients. In the H pylori+DU patients, the mean number of antral G cells was significantly lower in comparison with all other groups (P<0.01), but after successful eradication was close to normal values found in controls. By contrast, G cell number and volume density were significantly decreased (P<0.01) in H pylori+Ge group after successful eradication therapy (294±32 and 0.31±0.02, respectively), in comparison to values before eradication (416±40 and 0.48±0.09). No significant change of the G cell/total endocrine cell ratio was observed during the 6 mo of follow up in any of the groups. A reversible increase in G cell secretory function was seen in all infected individuals, demonstrated by a more prominent secretory apparatus. However, differences between DU and gastritis group were identified. CONCLUSION: H pylori infection induces antral G cell hyperfunction resulting in increased gastrin synthesis and secretion. After eradication therapy complete morphological and functional recovery is observed in patients with gastritis. In the DU patients some other factors unrelated to the H pylori infection influence antral G cell morphology and function.  相似文献   
90.
One of the obstacles to AIDS vaccine development is the variability of HIV-1 within individuals and within infected populations, enabling viral escape from highly specific vaccine induced immune responses. An understanding of the different immune mechanisms capable of inhibiting HIV infection may be of benefit in the eventual design of vaccines effective against HIV-1 variants. To study this we first compared the immune responses induced in Rhesus monkeys by using two different immunization strategies based on the same vaccine strain of HIV-1. We then utilized a chimeric simian/HIV that expressed the envelope of a dual tropic HIV-1 escape variant isolated from a later time point from the same patient from which the vaccine strain was isolated. Upon challenge, one vaccine group was completely protected from infection, whereas all of the other vaccinees and controls became infected. Protected macaques developed highest titers of heterologous neutralizing antibodies, and consistently elevated HIV-1-specific T helper responses. Furthermore, only protected animals had markedly increased concentrations of RANTES, macrophage inflammatory proteins 1α and 1β produced by circulating CD8+ T cells. These results suggest that vaccine strategies that induce multiple effector mechanisms in concert with β-chemokines may be desired in the generation of protective immune responses by HIV-1 vaccines.  相似文献   
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