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101.
Centrilobular emphysema: CT-pathologic correlation   总被引:5,自引:0,他引:5  
Over a 5-year period, 25 patients who had undergone chest computed tomography (CT) died and were autopsied. Their lungs were fixed in the inflated state and were assessed for the presence and severity of centrilobular emphysema (CLE). Three radiologists independently evaluated the CT scans for nonperipheral low-attenuation areas, peripheral low-attenuation areas, pulmonary vascular pruning, pulmonary vascular distortion, and pulmonary density gradient. The CT criterion that best correlated with the presence and severity of CLE was the nonperipheral low-attenuation area. With this CT criterion, lung destruction was correctly identified in 13 of 15 cases. The absence of this criterion resulted in correct identification of eight of ten normal lungs. These preliminary data suggest that CLE can be reliably identified and quantified with current CT scanners.  相似文献   
102.
Prevalence of antibodies to hepatitis C virus in the hemodialysis unit.   总被引:2,自引:0,他引:2  
An enzyme immunoassay was used to detect antibodies to hepatitis C virus (anti-HCV) in 261 patients and 69 staff members of a hemodialysis unit. The prevalence of anti-HCV was 46.7% in patients and 2.9% in staff members (p less than 0.001). The prevalence of anti-HCV increased significantly with increasing duration of hemodialysis (p less than 0.001), but was not related to age, sex, history of blood transfusion, status of hepatitis B or hepatitis A virus infection, or serum ALT. Patients with hepatitis episode increased with increasing duration of hemodialysis and showed a significantly higher prevalence of anti-HCV than those without (63.1 vs. 34.7%, p less than 0.001). The prevalence of anti-HCV in patients with hepatitis also increased with increasing duration of hemodialysis (p = 0.05). Thus, HCV appears to be the major cause of hepatitis in hemodialysis patients. Besides strict infection control measures, further studies are needed to determine the mode of HCV infection and its prevention in the hemodialysis unit.  相似文献   
103.
Fifty-two patients with clinical stage A and B carcinomas of the prostate were imaged by ultrasound (US) transrectally with a 5-MHz linear array transducer and transabdominally with a 3-MHz sector scanner prior to radical prostatectomy. The fresh specimens of 44 prostate glands were scanned in a water bath with a 5-MHz linear array transducer in multiple planes. In all cases, histopathologic correlation was obtained. Prostatic carcinoma presented as an echopenic lesion in 54% of the specimens, as a slightly hypoechoic area in 22%, and could not be identified in 24% because of its isoechoic characteristics. In contrast to many previous reports, no instance of echogenic cancer was observed.  相似文献   
104.
High-resolution magnetic resonance (MR) imaging with a surface coil was utilized to evaluate the normal scrotum. Scrotal contents, spermatic canal, and inguinal regions were visualized within the same field of view. Differences in signal intensity in the testis, epididymis, tunica albuginea, fluid, fat, and spermatic cord allowed for clear delineation of these structures in detail. The high contrast and spatial resolution of MR imaging, coupled with the wide field of view and absence of ionizing radiation, make MR imaging well suited for evaluation of the scrotum.  相似文献   
105.
The diagnostic value of biphasic radiographic examination of the stomach and duodenum was compared with that of fiberoptic endoscopy in a prospective, blinded study of 385 patients with dyspepsia. This investigation was directed at gastric malignancies and peptic ulcers. Methodologically there is no absolute standard for a study of this kind because histologic examination is useful for detection of cancer but inadequate for ulcers. As an alternative, kappa indexes and the sensitivity and specificity, as derived by Hui and Walter, were calculated and compared. For the detection of gastric carcinoma, radiographic and endoscopic findings had almost perfect agreement beyond chance. For gastric ulcers, radiography and endoscopy had substantial agreement, which became perfect if small ulcers (less than 5 mm) were excluded. For duodenal ulcers, radiography had a lower sensitivity than endoscopy; this disagreement disappeared if small ulcers were excluded. Both methods have equal merit; choice of the initial diagnostic procedure will therefore depend on cost, discomfort to the patient, and risk of complications.  相似文献   
106.
Medullary carcinoma of the breast: mammographic and US appearance   总被引:4,自引:0,他引:4  
  相似文献   
107.
Summary.  A liver slice culture-based, ex vivo drug suppression assay was developed as a pre-therapeutic predictor for the outcome of antiviral therapy. To investigate its clinical application, 106 consecutive patients with chronic hepatitis C virus (HCV) infection were evaluated. Ex vivo drug suppression assay was performed before administrating a standard course of peginterferon plus ribavirin combination therapy. Stepwise logistic regression model was used to estimate sustained virological response (SVR) on the presence of various clinicopathological parameters. Suppression of HCV replication in the ex vivo assay was present in 32 patients, 29 (90.6%) of whom achieved SVR. Stepwise logistic regression analysis indicated that the presence of interferon suppression effect in the ex vivo assay (odds ratio [OR], 5.552; 95% confidence interval [CI], 1.114–27.673; P  = 0.036), genotype 1 (OR; 0.045, 95% CI, 0.008–0.259; P  = 0.001), HCV-RNA level (OR, 0.739; 95% CI, 0.617–0.885; P  = 0.001), the presence of fatty metamorphosis (OR, 0.205; 95% CI, 0.053–0.793; P  = 0.022), and albumin (OR, 9.687; 95% CI, 2.237–41.940; P  = 0.002) were independent determinants of SVR. Categorical analysis revealed that 17 of 17 (100%) patients with genotype non-1 and positive ex vivo suppression test achieved SVR, while 20 of 40 (50%) with genotype 1 and negative ex vivo suppression test achieved SVR. In conclusion, the ex vivo drug suppression assay may serve as an independent pre-therapeutic predictor for the SVR in interferon-based antiviral therapy.  相似文献   
108.
A microcapillary method utilizing phthalate esters or an ultracentrifuge method are both capable of separating autologous from homologous erythrocytes in polytransfused patients. The microcapillary technique which is readily adaptable to blood bank laboratories provides a previously unavailable method for defining blood group antigen typings in transfused patients. Such typings are of vital importance in the laboratory evaluation of transfused patients with multiple or weak blood group antibodies.  相似文献   
109.
We evaluated the proportion of patients eligible for alternatives to standard whole breast irradiation (WBI) following breast‐conserving surgery using the National Cancer Database (NCDB). Using the 2016 dataset, Stage I‐III patients were identified. Eligibility for hypofractionated WBI (HFRT), accelerated partial breast irradiation (APBI) and endocrine therapy (ET‐alone) was defined using eligibility from large clinical trials as well as consensus guidelines. For patients with pN0 breast cancer, 20.6% and 37.0% were eligible for ET‐alone based on the CALGB 9343/PRIME‐II trials, respectively. In terms of HFRT, 72.5% and 50.4% were eligible based on IMPORT LOW/ASTRO HFRT guidelines, respectively. Based on IMPORT LOW/GEC‐ESTRO trial/ASTRO guidelines/ABS guidelines/GEC‐ESTRO guidelines, 72.5%, 86.1%, 39.0%, 72.5%, 45.7%, respectively, were eligible for APBI. Of those who qualify for HFRT per ASTRO guidelines, approximately 90% were eligible for APBI and 50% for ET‐alone. This analysis shows that a large proportion of patients with node‐negative breast cancer are eligible for HFRT, APBI and/or ET‐alone after breast‐conserving surgery.  相似文献   
110.
Total radical trapping antioxidant potential (TRAP) and exercise   总被引:1,自引:0,他引:1  
The relationship between physical activity, physical fitness and total radical trapping antioxidant potential (TRAP) was examined in the Northern Ireland Health and Activity Survey. This was a cross-sectional population study (n = 1600) using a two-stage probability sample of the population. TRAP was calculated using the sum of the individual serum antioxidant concentrations (urate, protein thiols, ascorbate, alpha tocopherol and bilirubin) multiplied by their respective stoichiometric values. Physical fitness was determined by estimation of VO2max by extrapolation from submaximal oxygen uptake, and physical activity was recorded by computer-assisted interview. Mean serum TRAP concentrations were significantly higher in males (653 +/- 8.2 mumol/l, mean +/- SEM) compared to females (564 +/- 8.0 mumol/l) (p < 0.0001). Both male and female smokers had significantly lower TRAP values than non-smokers (males p < 0.0001, females p = 0.02). In females, there was a positive relationship of TRAP with age (p < 0.001) and body mass index (p < 0.001) but a negative relationship with physical fitness (p < 0.05). The known beneficial effects of exercise and activity do not appear to be directly mediated through increased antioxidant status.   相似文献   
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