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131.
OBJECTIVE: To review the validity of the clinical assessment and diagnostic tests in patients with suspected deep vein thrombosis (DVT). METHODS: A comprehensive review of the literature was conducted by searching MEDLINE from 1966 to April 1997. RESULTS: Individual symptoms and signs alone do not reliably predict which patients have DVT. Overall, the diagnostic properties of the clinical examination are poor; the sensitivity of the clinical examination ranges from 60% to 96%, and the specificity ranges from 20% to 72%. However, using specific combinations of risk factors, symptoms, and physical signs for DVT, clinicians can reliably stratify patients with suspected DVT into low, moderate, or high pretest probability categories of actually suffering from DVT. This stratification process in combination with noninvasive testing, such as compression ultrasonography, simplifies the management strategies for patients with suspected DVT. CONCLUSIONS: Use of a clinical prediction guide that includes specific factors from both the history and physical examination in combination with noninvasive tests simplifies management strategies for patients with suspected DVT.  相似文献   
132.
For evaluation of the efficacy and the safety of specific sublingual immunotherapy with high allergen dose, 66 children with seasonal asthma, rhinitis, and conjunctivitis due to sensitization to olive pollen were enrolled in a double-blind, randomized, placebo-controlled study between October 1994 and October 1996 in Greece. Thirty-four patients were randomly allocated to the active group, and 32 received placebo. Immunotherapy consisted of olive-allergen extracts (Stallergènes SA) administered sublingually pre- and coseasonally from January to July for 2 consecutive years. Serial concentrations from 1 to 300 IR. were used up to the maintenance dose of 20 drops of 300 IR daily. The cumulative dose for each patient was 300 times higher than in parenteral immunotherapy, and the cumulative dose of the major allergen Ole e 1 was 8.1 mg/2 years. The patients were assessed by clinical parameters (symptom and medication scores from patients' daily diaries) and immunologic measurements (specific IgE, IgG4, eosinophil cationic protein [ECP]) were performed. The actively treated patients had a significantly lower score for dyspnea (P<0.04 during the first season; P<0.03 during the second season). At the pollinic peak during the second year, a lower score of conjunctivitis was recorded (P<0.05) in the actively treated patients. The analysis of intragroup evolution showed that the total score of rhinitis increased significantly during the pollinic peak in the group under placebo, whereas there was no symptomatic peak for the same period in the group under active treatment. However, the difference between the groups was not significant. The medication score did not differ significantly between the groups. Oral steroids were the only variables with a P value near the significance level (P=0.06) in favor of the actively treated group. A significant decrease in skin reactivity was recorded in the active group after 2 years of treatment. No significant variation in specific IgE and IgG4 was detected. A significantly lower level of serum ECP was observed at the pollinic peak in the actively treated patients during the first pollen season (P=0.01), but this was not confirmed the second year when the ECP levels doubled in both groups without correlation to the clinical findings. Tolerance was excellent with only a few minor side-effects reported. In conclusion, high-dose specific sublingual immunotherapy appears to be safe and effective in improving mild seasonal asthma and conjunctivitis linked to olive-pollen sensitization.  相似文献   
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After cardioversion from atrial fibrillation (AF) many patients develop early recurrence of the arrhythmia. While these patients may be appropriate for immediate prophylaxis against AF recurrence their identification at the time of cardioversion is not possible. Since the signal-averaged P wave (SAPW) is abnormal in individuals with atrial arrhythmia, we assessed its utility for predicting early AF recurrence after cardioversion. Seventy-five cardioversions in 31 patients were evaluated. The mean age was 59 (range 28-79) years; 26 were male. Fifty-eight cardioversions were internal using low energy biphasic DC shocks delivered via electrodes placed in the right atrial appendage and coronary sinus. P wave specific signal averaging was performed at 3 and 24 hours after each cardioversion to estimate filtered P wave duration and energy from 20, 40, and 60 to 150 Hz. Follow-up was by regular clinic visits and transtelephonic ECG monitoring. Early recurrence of AF (prospectively defined as sinus rhythm duration < 1 week) occurred after 30 cardioversions. No differences were found in any P wave variable measured at 3 hours between these cardioversions and those that resulted in a longer duration of sinus rhythm. Paired 3- and 24-hour signal-averaged data were available in 47 cardioversions. There were significant falls in P wave energy from 3 to 24 hours after 31 cardioversions that resulted in sinus rhythm for > 1 week, (P40: 3 hours 11.2 [+/- 1.5] micro V2.s, 24 hours 8.6 [+/- 1.2] micro V2.s, P < 0.001), but not following the 16 after which AF returned within 1 week (P40: 3 hours 9.0 [+/- 1.2] micro V2.s, 24 hours 8.5 [+/- 1.2 micro V2.s, P = NS). A fall in P40 of > 25% had a positive predictive accuracy for maintenance of sinus rhythm of 87%; negative predictive accuracy was only 37%. Similar falls in P wave energy occurred after cardioversions that resulted in longer term (> 4 weeks) sinus rhythm, but not in those that did not. However, the predictive accuracy of a fall in P40 was less (positive predictive accuracy 38%, negative predictive accuracy 62%). Patients with relapsing permanent AF who remain in sinus rhythm for at least 1 week after cardioversion show a fall in P wave energy within the first 24 hours. However, in these patients the technique does not predict recurrent AF within 1 week nor sinus rhythm > 4 weeks. These observations suggest persistent disordered atrial activation as a mechanism for early recurrence of AF after cardioversion.  相似文献   
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136.
Allosensitization is a fundamental problem that limits the effectiveness of blood transfusions. Patients who receive multiple transfusions of blood or blood components frequently develop alloantibodies against donor alloantigens. Allosensitized patients are refractory to further transfusion and difficult to transplant successfully. CTLA4Ig fusion protein, which blocks the CD28-B7 costimulatory pathway in T-lymphocyte activation, was tested for its capacity to inhibit allosensitization to blood transfusions. Groups of LEW (RT1') rats were transfused with ACI blood (RT1a) together with L6 (a human immunoglobulin G1 [IgG1] antibody as isotype control) or CTLA4Ig in different doses (0.004, 0.02, 0.1, and 0.5 mg). Rats were retransfused with ACI blood after 28 and 84 days without any additional CTLA4Ig therapy. Weekly sera samples were tested for alloantibody against donor leukocytes using flow cytometry. CTLA4Ig caused a dose-dependent decrease in the IgM alloantibody response against donor major histocompatibility complex (MHC) class I antigens. In addition, 0.02-, 0.1-, and 0.50-mg doses of CTLA4Ig totally inhibited the IgG responses to the first transfusion, and this immunosuppressive effect persisted for the second and third transfusions. To study the capacity of CTLA4Ig to prevent a secondary immune response, three groups of LEW rats were transfused with ACI blood with no accompanying treatment. Animals were retransfused 28 days later with ACI blood together with L6 control antibody or 0.5 or 2.5 mg CTLA4Ig. CTLA4Ig, but not L6, prevented an increase in IgG alloantibody response despite repeated transfusions. The effects of CTLA4Ig treatment on helper T-lymphocyte proliferation was tested by limiting dilution analysis (LDA). Peripheral blood cells taken 30 days after blood transfusion and CTLA4Ig treatment contained significantly decreased donor-specific T-lymphocyte precursors compared with L6-treated rats. These data support the idea that blocking the B7/CD28 signal of T-lymphocyte activation by CTLA4Ig treatment at the time of transfusion may be an important therapeutic tool to inhibit alloantibody responses to blood transfusions.  相似文献   
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OBJECTIVE: To identify exposures to etiologic agents and to identify characteristics that could explain risk of disease for adult cattle in herds affected by winter dysentery (WD). ANIMALS: 229 lactating and nonlactating adult cattle (125 case and 104 control cattle) selected from 12 dairy herds. PROCEDURE: A case-control study, using multivariate conditional logistic regression and controlling for herd effects, was used to develop a model for risk factors associated with disease for each cow. RESULTS: Likelihood of developing disease increased as the ELISA value for bovine coronavirus (BCV) antigen detectable in feces increased (odds ratio [OR] = 2.94 for each 0.100 increase in BCV antigen ELISA value). Pregnant cattle were less likely to develop WD, compared with nonpregnant herdmates. Cows with high acute BCV antibody titers that seroresponded had greater odds of developing disease, compared with seroresponding cows with low acute titers. However, among those cows that did not serorespond, high acute antibody titers were associated with lower odds of developing the disease. CONCLUSION: In herds affected by WD, ill cows were more likely to shed detectable amounts of BCV antigen in their feces, and pregnancy appeared to protect cattle from the disease. The measured interaction between BCV seroresponse and acute BCV antibody titer may be evidence of an immunopathologic condition, but could also have been attributable to dynamics of the ELISA or study design. CLINICAL RELEVANCE: Factors that explained a cow's risk for illness within WD-affected herds may have been surrogate measures for that cow's nonspecific and BCV-specific immune profile.  相似文献   
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140.
This study investigated the actual growth rate of 30 low stage operable non-small cell lung carcinomas, including disease-free surviving and deceased patients. The actual growth rate was defined as the cell production rate and was calculated from the growth fraction and the cell cycle time of each tumor at the time of surgical resection. The growth fraction was assessed by the Ki67 index while the cell cycle time was assumed to be reflected by the AgNORs content in the cells positive for Ki67. AgNORs content was evaluated by means of image analysis of double-stained AgNOR-Ki67 tissue section. The actual growth rate did not discriminate between the disease-free surviving and deceased patients but the AgNORs content in Ki67 cells correlated with the survival time of those patients who died of the tumor. Patients expressing a small AgNORs content, which might indicate a long cell cycle, may die but later; patients with a high AgNORs content, which might indicate a short cell cycle, die early or will survive. A twilight curve was derived from this data and might provide new prognostic indicators.  相似文献   
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