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排序方式: 共有8848条查询结果,搜索用时 15 毫秒
31.
32.
Physicians, vital statistics, and disease reporting 总被引:1,自引:0,他引:1
33.
34.
The chest radiographs obtained in nine patients with acquired immunodeficiency syndrome (AIDS) and pulmonary toxoplasmosis were reviewed. In three patients, a bilateral, diffuse, fine to medium reticulonodular pattern indistinguishable from that seen in Pneumocystis carinii pneumonia (PCP) was observed. In six patients, however, a bilateral, predominantly coarse, nodular pattern was observed. This type of abnormality is unusual with PCP, and its presence may help in distinguishing between pulmonary infections caused by Toxoplasma gondii and P carinii. Other opportunistic pneumonias occurring in patients with AIDS, including tuberculosis, histoplasmosis, and coccidioidomycosis, might show similar coarse, nodular opacities on chest radiographs and thus may not be differentiated from pulmonary toxoplasmosis. No hilar or mediastinal adenopathy was observed. Two patients had pleural fluid. Radiologists familiar with the chest radiographic appearance of T gondii pneumonia could be first to suggest this unusual complication of AIDS. 相似文献
35.
36.
Mechanoregulation of human articular chondrocyte aggrecan and type II collagen expression by intermittent hydrostatic pressure in vitro. 总被引:6,自引:0,他引:6
37.
38.
M P Joseph M L Goodman B Z Pilch F R Bieber L B Holmes E Reardon 《Head & neck surgery》1986,8(6):456-462
Heterotopic cervical salivary gland tissue was found in a 4-yr-old girl with branchial and otologic abnormalities. Her mother and sister also had heterotopic cervical salivary tissue in association with anomalies that suggest the branchio-otorenal (BOR) syndrome. Heterotopic cervical salivary gland tissue may result from abnormal branchial development. 相似文献
39.
Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
相似文献
40.
Leukotriene B4 (LTB4) and the protein kinase C activator, 4-beta-phorbol dibutyrate (PDBu), both induced a pronounced and concentration-dependent stimulation of hydrogen peroxide (H2O2) generation by purified guinea pig peritoneal eosinophils in the concentration range 1 nM-1 microM. The LTB4 response was inhibited competitively by the specific LTB4 receptor antagonist, U-75302, with a KB of 25 nM, while the concentration-response curves for both stimuli were shifted rightwards (3.8-fold and 2.8-fold for LTB4 and PDBu, respectively) by the competitive protein kinase C inhibitor, 1-O-hexadecyl-2-O-methylglycerol at a concentration of 300 microM. LTB4 appears, therefore, to induce respiratory burst in eosinophils via a receptor-mediated mechanism involving protein kinase C. 相似文献