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21.
The buoyant density in cesium chloride of the human reoviruslike (HRVL) agent of infantile gastroenteritis was studied utilizing electron microscopy and complement fixation (CF) for the detection of reoviruslike particles in fractions of the density gradient. Three virus positive stool filtrates were studied. “Full” reoviruslike particles had a density of 1.35–1.37 g/cm3, whereas “empty” particles had a density of 1.29 g/cm3. Peak CF activity coincided with the peak fraction of both the “full” and “empty” reoviruslike particles. In addition, by differential centrifugation, CF activity was also associated with the virion and not a “soluble” antigen.  相似文献   
22.
The objective of this study is to design a new apparatus to allow the control of the magnitude and frequency of dynamic stretch applied uniformly to cells cultured on a silicon elastic membrane. The apparatus is designed to produce equi-biaxial dynamic stretches with area changes ranging from 0% to 55% and frequencies ranging from 0 to 2 Hz. Homogeneous finite strain analysis using triangles of markers was performed to compute the symmetric two-dimensional Lagrangian strain tensor on the membrane. Measurements of strain in both static and dynamic conditions showed that the shear component of the strain tensor (Erc) was near zero, and that there was no significant difference between radial (Err) and circumferential (Ecc) components, indicating the attainment of equi-biaxial strain. Bovine aortic endothelial cells were transiently transfected with a chimeric construct in which the luciferase reporter is driven by TPA-responsive elements (TRE). The transfected cells cultured on the membrane were stretched. The luciferase activity increased significantly only when the cells were stretched by 15% or more in area. Cells in different locations of the membrane showed similar induction of luciferase activities, confirming that strain is uniform and equi-biaxial across the membrane. © 1998 Biomedical Engineering Society. PAC98: 8780+s, 8745-k, 8722-q  相似文献   
23.
The cholinergically innervated human eccrine sweat gland is a readily available organ permitting the assessment in allergic patients of cholinergic reactivity with few or no adrenergic influences. The sweat responses of four matched groups (male allergic, female allergic, male control, and female control) to intradermal Mecholyl from 0.1 μg to 100 μg was compared; the 45 male and 45 female allergic patients demonstrated statistically significant increases in sweat responses to essentially all concentrations of Mecholyl examined. No difference in the sweat responses of patients with allergic rhinitis alone as compared with patients with both allergic rhinitis and allergic asthma was noted. Five patients with intrinsic asthma most closely resembled the allergic groups in their responses and 8 patients with vasomotor rhinitis sweated at or below the control groups. The increased sensitivity of allergic patients to cholinergic stimulation as measured by eccrine sweat responses suggests that this hyperresponsiveness may be one of the underlying defects in allergic disease.  相似文献   
24.
The clinical laboratory is regarded as a component of the medical care system extending from physician to laboratory staff and back to physician. From this concept a computer-based system of laboratory information is derived, emphasizing: (1) total laboratory responsibility for the test and its request, and (2) physician-oriented output reports.  相似文献   
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26.
Growth of diploid cells from breast cancers   总被引:1,自引:0,他引:1  
Cell cultures were derived from normal and cancerous breast tissues and from metastases by methods that selected for relatively adherent epithelial aggregates. Karyotypic analyses of first or second passage cultures yielded predominantly normal diploid cells. Nonclonal aberrations were more common in tumor-derived than in normal cultures. Three of the cultures that originated from metastases were characterized by abnormal clones. These results support observations based on DNA content, which indicate that a considerable fraction of breast cancers are composed predominantly of diploid cells. They differ greatly from chromosomal findings in long-term cultures of tumor effusions and thus emphasize the karyotypic diversity that can be found in tumors from a single tissue of origin--the breast.  相似文献   
27.
Several recent reports have described cases of acute nonlymphocytic leukemia with a unique chromosome translocation, t(6;9)(p23;q34). We have studied three additional patients who have acute nonlymphocytic leukemia and t(6;9)(p23;q34). Our findings provide additional support for the suggestion that this translocation is yet another distinct cytogenetic abnormality associated with myeloproliferative disorders.  相似文献   
28.
Since the mid 196O's there has hcen a growing interest in and use of computers in psychophysiology laboratories. There are even a growing number of accepted physiological measures which are fully dependent on computer technology for their derivation. Although minicomputers have been in use for over a decade, recent developments in microcomputer and microprocessor technology have led to rapid acceptance of microcomputers for laboratory work. These rapid advances have produced a need to survey the current state of laboratory computer applications and development. A comprehensive survey was mailed to 301 psychophysiology laboratory groups during the spring and summer of 1979 and completed surveys were received from 61% of the mailing. Sun'ey results are reported on computer hardware and configuration, dependent measures and user satisfaction, and use and cost of engineering and programming support. Developments in computer hardware and user services are also discussed.  相似文献   
29.
Neonatal infection of C57BL and BALB/c mice by cloned ecotropic and dualtropic mink cell focus-inducing (MCF) murine leukemia viruses (MuLV) induces a wide spectrum of different lymphomas of T, B, and non-T/non-B cell types. Oncogenic dualtropic MCF viruses and poorly oncogenic ecotropic MuLV act synergistically in lymphomagenesis. Within one mouse strain virus-induced T-cell lymphomas arise earlier than B-cell lymphomas after neonatal inoculation of a single-cloned MuLV. The host genetic constitution, notably the H-2 complex has a marked influence on lymphoma type. This H-2 influence can be explained by an H-2-linked difference in penetration of the thymus early in life by oncogenic thymotropic MuLV, which in turn is correlated with, but not necessarily due to the magnitude of the anti-MuLV antibody response.  相似文献   
30.
目的探讨前列地尔辅助硫辛酸治疗糖尿病足溃疡合并感染对患者胰岛素样生长因子-1(IGF-1)、纤维连接蛋白(FN)、血管内皮生长因子(VEGF)水平及足背血流动力学的影响。方法选取2017年5月-2019年5月新疆医科大学第一附属医院收治的104例糖尿病足溃疡合并感染患者,采用随机数字表法将所选患者分为研究组(n=52)和对照组(n=52)。对照组给予硫辛酸进行治疗,研究组在此基础上给予前列地尔进行治疗,两组均治疗4周。比较两组治疗4周后的下肢静息疼痛改善情况,治疗前、治疗4周后的血清IGF-1、FN、VEGF水平及足背动脉血流速度和足背动脉内径,统计两组治疗期间的不良反应发生率。结果治疗4周后,研究组下肢静息疼痛总改善率为96.15%,高于对照组(P<0.05)。与治疗前比,治疗4周后,两组血清IGF-1、FN、VEGF水平及足背动脉血流速度、足背动脉内径均升高,且研究组均高于对照组(P<0.05)。治疗期间,研究组不良反应发生率为5.77%,低于对照组(P<0.05)。结论前列地尔辅助硫辛酸治疗糖尿病足溃疡合并感染,可显著提高患者血清IGF-1、FN、VEGF水平,改善其足背血流动力学,并能缓解患者下肢静息疼痛,降低不良反应发生率。  相似文献   
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