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排序方式: 共有277条查询结果,搜索用时 15 毫秒
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The coexistence of large granular lymphocytic leukemia (LGLL) and pure red cell aplasia (PRCA) has been previously described, but is rare in Western countries (7% in a recent series of LGLL cases). We present the clinical features, hematological parameters and immunophenotype of two patients with PRCA associated with CD3+ LGLL. 相似文献
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PW Wiest MF Hartshorne PD Inskip LA Crooks BS Vela RJ Telepak MR Williamson R Blumhardt JM Bauman M Tekkel 《Canadian Metallurgical Quarterly》1998,17(8):487-496
Detection of thyroid nodules by physical examination and high-resolution ultrasonography was compared using small groups of blinded, experienced physician examiners working with a sample of 2441 persons from Estonia, most of whom were Chernobyl nuclear reactor clean-up workers. A random subsample of 113 (5%) persons was subjected to triple control examinations with both physical examination and high-resolution ultrasonography. Positive high-resolution ultrasonographic findings were considerably more reproducible among different observers than were positive physical examination findings. Agreement between methods was poor. Nodules were found in 169 (6.9%) subjects by physical examination and in 249 (10.2%) subjects by high-resolution ultrasonography. Physical examination found only 53 (21%) of the 249 nodules found by high-resolution ultrasonography. High-resolution ultrasonography did not confirm the existence of 115 (68%) of the 169 nodules found by physical examination. Only 6.4% of nodules less than 0.5 cm in diameter, as based on high-resolution ultrasonographic results, were detected by physical examination. Physical examination detection improved with increasing nodule size but was still only 48.2% for nodules larger than 2 cm. Physical examination was relatively effective in detecting nodules in the isthmus of the thyroid gland but much less so for nodules in the upper pole of the gland. Clinical evaluation and epidemiologic studies of nodular thyroid disease stand to benefit from the greater sensitivity and specificity of ultrasonographic examinations. 相似文献
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OBJECTIVE: To carry out a prospective study on 1,569 females to evaluate the diagnostic utility of adding buffered Wright solution to Papanicolaou stain for observing cytoplasmic inclusions in cervicovaginal cytology. STUDY DESIGN: Group A had multivacuolated cells and group B, granules (not in a vacuole) in the cytoplasm of low-intermediate epithelial or parabasal cells. There were 7 patients in group A and 16 in group B. Two duplicate plates of cervicovaginal secretions were obtained from each patient before and after treatment; one was stained with Papanicolaou stain and the other with our variant. The trial of therapy consisted of doxycycline (effectiveness for statistical analysis = 0.9) in oral doses of 100 mg every 12 hours for 7 days; 7 days after the beginning of treatment, check samples were obtained. RESULTS: In group A, six patients had cytoplasmic inclusions with the variant stain, and two had cytoplasmic inclusions with Papanicolaou stain. The binomial test revealed that probably six of the seven patients had infections with Chlamydia (P = .372) and that in 100% of cases, the variant stain showed cytoplasmic inclusions, while Papanicolaou stain was observed in 33% of cases. These findings were morphologically and statistically proven (P = .124) on control slides with posttreatment absence of multivacuolated cells. CONCLUSION: In relation to the selection criteria for B group, the intracytoplasmic granules found in parabasal and low intermediate cells had no relation to Chlamydia. The study demonstrated the superiority of our variant of Papanicolaou stain for cervicovaginal Chlamydia diagnosis. 相似文献
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The effects of elevated blood lead on semen quality were evaluated in the rabbit model and compared to published effects in humans. Mature, male rabbits were given lead acetate by subcutaneous injection in the dose range of 0 to 3.85 mg/kg on a Monday-Wednesday-Friday basis. In each of eight treatment groups, a dosing regimen was developed to produce blood lead levels of 0, 20, 40, 50, 70, 80, 90, and 110 microg/dL. A 5-week pre-exposure period was followed by a 15-week exposure testing period allowing for response through six cycles of the seminiferous epithelium. Semen analyses revealed that increased blood lead levels were associated with adverse changes in the sperm count, ejaculate volume, percent motile sperm, swimming velocities, and morphology. Hormonal responses were minimal. Testicular pathology revealed a dose-dependent inhibition of spermiation. For six measures of semen quality, threshold estimates ranged from 16 to 24 microg/dL. Using the species extrapolation factor derived in this study, a rabbit dose would have to be divided by 1.56 to obtain the equivalent human dose for an equal percentage decrease in sperm concentration; however, rabbits are 3.75 more sensitive in terms of absolute decrease in sperm count for a given blood lead level. 相似文献
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Two-level fractional factorial designs were employed to study the solution polymerization of butadiene in a batch reactor using cobalt octoate/DEAC/water as catalyst. Conversion and molecular weight data obtained as functions of time were used to develop a kinetic model, and the estimated kinetic parameters were correlated empirically with four operating variables: temperature and concentrations of cobalt octoate, DEAC, and water. The experimental data indicate that at high water concentration a significant amount of oligomers is formed during early stages of polymerization, and the molecular weight of polymer increases with time. Analysis of the data suggests instantaneous initiation, first order propagation with cobalt and monomer, and transfer to monomer. Models which do not take account of the branching are shown to be incapable of fitting data for both M n and M w. The catalyst decay seems to follow a first-order mechanism, but the evidence is somewhat inconclusive. 相似文献
28.
JF Meco X Pintó JM Escribà M Vela F Jara C Pallarés MJ Casti?eiras R Pujol 《Canadian Metallurgical Quarterly》1998,28(8):643-650
BACKGROUND: Patients with coronary artery disease (CAD) associated with peripheral (PAD) or cerebrovascular disease (CVD), a condition called diffuse atherosclerosis, have a higher risk of death than patients with isolated CAD. The prevalence of diffuse atherosclerosis and the atherogenic risk factors associated with this condition in our geographic area have not been described previously. METHODS: A cohort of 2597 patients (62 +/- 10.8 years, 665 women) consecutively admitted at Bellvitge Hospital because of acute coronary syndromes were studied. CAD patients were divided in two groups with diffuse and located atherosclerosis according to whether they had or they had not an associated PAD or CVD. Baseline history, physical data and lipid profile were recorded in each patient according to a standardized questionnaire. RESULTS: A total of 370 patients (14.2%) had diffuse atherosclerosis. Among them, there were more men and women older than 55 years than among those with isolated CAD. Patients with diffuse atherosclerosis were more frequently hypertensive, diabetic and former smokers than those with isolated CAD (60.5% vs. 49.4%, P < 0.01; 37.4% vs. 24.5%, P < 0.01; and 47% vs. 35.7%, P < 0.01, respectively). There were no significant differences in the mean values of total cholesterol (TC), low-density cholesterol (LDL-C), high-density cholesterol (HDL-C) and triglycerides between both groups of patients, but patients with diffuse atherosclerosis had a lower HDL-C/TC ratio, with borderline statistical significance (0.18 +/- 0.06 vs. 0.19 +/- 0.06, P = 0.06). Using multiple logistic regression analysis, the variables associated with diffuse atherosclerosis in men were age greater than 55 years (OR 1.97, CI 1.33-2.93), hypertension (OR 1.50, CI 1.14-2.20), diabetes (OR 1.78, CI 1.20-2.70), smoking (former smokers) (OR 2.09, CI 1.36-3.24) and HDL-C/TC < 0.20 (OR 1.60, CI 1.18-2.17); and in women hypertension (OR 3.43, CI 1.48-7.94) and diabetes (OR 2.58, CI 1.55-4.80). CONCLUSIONS: Clinically overt diffuse atherosclerosis is a relatively common disease. Older patients and those with hypertension, diabetes or low HDL-C/TC ratio are more likely to have diffuse atherosclerosis than those without these conditions. 相似文献
29.
CAGLIARI-PADOVA-TORINO Collaboration L. Cugusi M.P. Macciotta S. Marcello A. Masoni G. Puddu A. Raimondi S. Serci M.T. Sergi M. Agnello F. Iazzi B. Minetti T. Bressani A. Feliciello A. Musso R. Cherubini F. Gramegna M. Morandin J. Lichtenstadt 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1988,270(2-3):354-360
The operating performances of a low-momentum (< 270 MeV/c) tagged
beam are reported. The
beam is obtained by means of the charge exchange reaction
n on a liquid hydrogen target. The neutron associated to the
in the two-body reaction is used for the determination of the
energy and direction. The measured total rate of tagged
is 8.02 ± 0.03 × 10−5 per incident
at 300 MeV/c. 相似文献
30.