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1.
The objectives of this study were 1) to determine the onset of a heritable reproductive disorder in the rooster that is characterized by extensive spermatozoal degeneration within the ductus deferens, and 2) to determine if autoimmunity was associated with spermatozoal degeneration. Seventy-five percent of the affected roosters did not ejaculate large percentages of degenerate spermatozoa at 20 wk of age, approximately the age of sexual maturity. Rather, seminal quality gradually declined over the next 6 wk, as both ejaculate volume and number of spermatozoa ejaculated increased. The evaluation of testicular and excurrent duct tissues via immunofluorescence failed to reveal either IgY or IgA associated with spermatozoa. While histological examination revealed greater lymphocyte numbers (P less than .05) in the proximal ductus deferens, these cells were not associated with spermatozoa nor spermatozoal clumping. While spermatozoal degeneration tends to be latent at the onset of semen production, it does not appear to be due to spermatozoal autoimmunity. 相似文献
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S K Powers J Lawler D Thompson R Beadle 《Aviation, space, and environmental medicine》1987,58(4):323-327
The purpose of these experiments was to develop and validate an open-circuit technique for measurement of gas exchange during the transition from rest to constant load steady-state exercise. The design of the open-circuit system employed to measure gas exchange in these experiments used a mixing chamber to collect the subject's expired ventilation where fractions of O2 and CO2 were determined via electronic gas analyzers. A gasometer was used to measure inspired ventilation and the analog signals from the two gas analyzers and the gasometer were sent to a microcomputer for computation of VO2. In calculating VO2, the mixed expired gas concentrations were matched with ventilatory volume using a previously determined time delay. To determine the validity of the open-circuit system, four subjects performed a series of 16 rest-to-work transitions on a cycle ergometer. In eight of the experiments, serial measurements of VO2 were obtained every 20 s for 3 min using the open-circuit mixing chamber system while the additional eight experiments used the Douglas bag technique. No significant difference (p greater than 0.05) existed between VO2 values calculated by the two techniques. Mean differences in VO2 between the two techniques during the first three 20-s measurement periods were 6, 53, and 63 ml, respectively. Using the Douglas bag technique as the standard, this represents a relative measurement error of 0.1%, 4.5%, and 3.6%, respectively, at the above time intervals. These data demonstrate that an open-circuit system employing a mixing chamber and the appropriate time delay to match expired gas fractions and ventilation is a sensitive means of measurement of VO2 in the non-steady-state. 相似文献
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Linkage of Chido and HL-A 总被引:6,自引:0,他引:6
6.
Leo P. Lawler Susan A. Wood Harpreet S. Pannu Elliot K. Fishman 《Journal of digital imaging》2003,16(3):251-261
The continued revolution in multidetector-row CT (MDCT) scanning increases the quality of lung imaging but at the cost of a greater burden of data for review and interpretation. This article discusses our preliminary experience with prototype software for lung nodule detection and characterization using MDCT data sets. We discuss the potential role of computer-assisted detection (CAD) as applied to the automatic detection of lung nodules. We also review the process of CAD, outline its potential results, and explore how it may fit into existing radiology practice. Finally, we discuss MDCT data-acquisition parameters and how they may affect the performance of CAD. 相似文献
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Paul A. Obrist Richard A. Galosy James E. Lawler Claude J. Gaebelein James L. Howard Emily M. Shanks 《Psychophysiology》1975,12(4):445-455
The relationships between heart rate (HR) and several parameters of somatic activity were evaluated in human subjects when shuck avoidance was made contingent on either increases or decreases in HR. In order to depict any influence of the contingency specific 10 HR, somatic activity was controlled to varying degrees by instructions and the use of non-contingent control groups. When increases in HR were reinforced, the contingency we found to influence somatic activity but an effect specific to HR was also observed. When decreases in HR were reinforced, there was no evidence that HR were influenced independently of somatic activity. The result are discussed with respect to several current issues. 相似文献
9.
Seventy-eight patients with Burkitt's lymphoma and seventy controls from Ghana were typed for HLA-A, B, C and DR antigens, to determine whether there is an association between the HLA system and Burkitt's lymphoma. Increased relative risk was observed in Burkitt's lymphoma patients with DR7, HLA-A1 and B12 (BW44). 相似文献
10.
IgM associated primary diffuse mesangial proliferative glomerulonephritis. 总被引:2,自引:3,他引:2 下载免费PDF全文
Twenty-three cases of IgM associated primary diffuse mesangial proliferative glomerulonephritis are presented. In 18, IgM was the sole localising host immunoglobulin, and it was the predominant globulin in five; C3 was also present in 18. Light microscopy revealed variable diffuse and global mesangial proliferation in all cases, with additional focal global sclerosis in 16, focal segmental sclerosis in 15, and small capsular crescents in seven. Material for electron microscopy was available from 19 patients; in 13, occasional intramesangial electron dense deposits were identified, and in 18 there were irregular, rather ill defined areas of increased electron density in mesangial regions. Clinically, 14 patients presented with the nephrotic syndrome, and nine had asymptomatic proteinuria. During follow-up, only 10 patients showed no change in renal function or improved; the remainder showed increasing hypertension and/or renal function deterioration and four developed end stage renal failure. It is suggested that IgM associated mesangial proliferative glomerulonephritis should be considered as a distinct clinicoimmunopathological entity. 相似文献