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991.
To evaluate the separation efficiency of Ericsson's two- and three- layer
albumin separation methods, semen samples from 21 healthy males were
studied. Seven patients already had two or more sons, another seven had two
or more daughters and the other seven had primary infertility due to female
factors. The semen samples were divided into three aliquots: one remained
unprocessed initially, the other two aliquots went through two- and
three-layer albumin separation methods respectively. All samples were then
stained with X-Y double staining probes. In each group, four or five
samples were processed at room temperature, and two or three at body
temperature (37 degrees C). The labelling efficiency of X-Y double staining
probe was over 99%. The X:Y sperm ratios were even in the original samples.
The ratios of the X and Y spermatozoa were altered slightly but
significantly after the two- layer (P < or = 0.05) or the three-layer (P
< or = 0.005) separation. The alterations occurred only at room
temperature. The X spermatozoa increased and the Y spermatozoa decreased,
both to a small degree of difference (1.4-3.5%). Double fluorescence
in-situ hybridization analysis therefore showed that albumin separation
methods do not enrich Y spermatozoa.
相似文献
992.
Hovsepian DM; Bonn J; Eschelman DJ; Shapiro MJ; Sullivan KL; Gardiner GA Jr 《Radiology》1994,190(1):137
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995.
PA Clavien CA Camargo Jr R Cameron MK Washington MJ Phillips PD Greig GA Levy 《Gastroenterology》1996,110(6):1891-1896
BACKGROUND & AIMS: Graft-versus-host hemolysis (GVHH) syndrome develops in approximately half of patients undergoing ABO-unmatched liver transplantation. The clinical and laboratory presentations of GVHH syndrome often mimic acute rejection, leading to liver biopsy for definitive diagnosis. The purpose of this study was to investigate if there are specific histological findings that permit diagnosis of GVHH syndrome and to assess the relationship between GVHH syndrome and rejection. METHODS: Clinical and laboratory evidence of GVHH syndrome, results of liver biopsy, and clinical outcome were assessed in 30 ABO- unmatched liver transplant recipients. Biopsy results were compared with those of two control groups consisting of patients who had normal liver test findings (protocol biopsy) and rejection. RESULTS: Sixteen of the 30 patients (53%) had evidence of GVHH syndrome. Erythrophagocytosis was noted in each biopsy specimen, and the degree of phagocytosis correlated significantly with the amount of blood given after postoperative day 5 (r = 0.9; P < 0.02). Electron-microscopic studies performed randomly in 5 patients showed that the red cells were located in Kupffer cells. In contrast, erythrophagocytosis was minimal in the two control groups. Despite an incidence and severity of rejection similar to those in other liver transplant patients, serum transaminase levels were significantly higher in patients with GVHH syndrome. CONCLUSIONS: Erythrophagocytosis is a sensitive histological marker of GVHH syndrome. The severity of rejection and response to antirejection therapy should be monitored by markers other than transaminases in patients with GVHH syndrome. (Gastroenterology 1996 Jun;110(6):1891-6) 相似文献
996.
997.
Periosteal ganglia: CT and MR imaging features 总被引:8,自引:0,他引:8
998.
The case of a 52-yr-old female with rheumatoid arthritis and HIV who developed massive, progressive, cavitary pulmonary nodules is described. Multiple diagnostic bronchoscopies and lung biopsies failed to demonstrate the presence of any microorganisms. Pathological analysis showed palisading histiocytes with necrobiosis consistent with rheumatoid nodules. The effect of co-existing HIV infection on the course and prognosis of rheumatoid arthritis is discussed, and it is concluded that the complex relationship between these two disease processes warrants further investigation. 相似文献
999.
Derivatives of sulfur-containing or sulfur-free α-amino acids, 4-aminobenzoic and 4-methoxycinnamic acids, which are potential sun screens, have been synthesized. The effects on melanin formation of 2 compounds (2 and 12) were studied via enzymatic reactions and cell culture. It was shown that these 2 compounds can enhance pigmentation. 相似文献
1000.