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921.
Endoscopic sclerotization of esophageal wall has been performed in 48 patients with bleeding of esophageal varices. The mortality rate in the acute bleeding was 29,2%. There was no mortality, if sclerotherapy was done in the non hemorrhagic interval. Of the 48 patients 25 are still alive, 8 more than 2 years without bleeding. In 12 cases we performed transhepatic obliteration of the V. coronaria ventriculi. Only in 3 of them no further hemorrhage occurred within 6 months. Fibrosclerotization seems to be superior to the transhepatic obliteration, because the primary mortality and complications are lower and long term results better.  相似文献   
922.
In rats narcotized by urethan we investigated the effect of 2,4-dinitrophenol and ouabain with regard to the cortical release of acetylcholine stimulated by scopolamine and to the acetylcholine content of telencephalon changed in that way. Dinitrophenol increased the liberating effect of scopolamine. In the presence of dinitrophenol and scopolamine ouabain reduced acetylcholine synthesis resulting in an strong decrease of acetylcholine content on persistent diminished increase of acetylcholine release.  相似文献   
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Thirteen AI organizations provided identification of herds that participated in their progeny test programs in 1989 and 1990; 15% of those herds participated in programs of more than one AI organization, but only 2.6% participated in programs of more than two AI organizations. Of the 19,589 participating herds, 82 and 76% were enrolled in DHI test plans that were considered to be usable for genetic evaluations during 1991 and 1992. For herds that had participated in AI progeny test programs, mean percentages of usable records were 77% in 1991 and 78% in 1992; the mean percentages of usable records for nonparticipating herds were 62% in 1991 and 60% in 1992. Participating herds had larger mean herd sizes, higher means and standard deviations of milk yields, younger cows, and a lower percentage of registered cows than did nonparticipating herds. Analysis of variance was used to explain the variation in the percentage of records that were usable for genetic evaluations. Herds that participated in AI progeny test programs or that had smaller herd sizes, higher mean milk yields, younger cows, or larger percentages of registered cows had higher percentages of records that were usable for genetic evaluations. Improved usability of records for genetic evaluations would increase the efficiency of AI progeny testing, and consideration of herd characteristics associated with higher percentages of usable records should aid AI organizations in evaluating prospective herds for progeny test programs.  相似文献   
926.
An enzyme-linked immunosorbent assay-based attachment model using the human intestinal cell line Caco-2A was developed to study attachment of Cryptosporidium parvum sporozoites in vitro and to assess potential inhibitors of sporozoite binding. In this system, attachment was related to sporozoite dose, incubation time, and host cell differentiation status. Polyclonal antibodies to C. parvum as well as glycoprotein inhibitors of a sporozoite lectin reduced attachment. This model will be a valuable tool in elucidating specific molecules and mechanisms involved in sporozoite-host cell attachment.  相似文献   
927.
Endothelin-1 (ET-1) is found in bronchoalveolar lavage fluid in patients following lung transplantation. ET-1 causes contraction of isolated pulmonary vessels and bronchi and stimulates proliferation of smooth muscle cells in culture. Therefore, ET-1 could contribute to the smooth muscle hyperplasia and stromal proliferation seen in chronic rejection of lung allografts. Experiments were designed to determine whether (1) ET-1 stimulates proliferation of pulmonary tissue, (2) proliferation is increased in rejecting allotransplanted lungs, (3) endothelin-A receptors mediate the proliferative response, and (4) ET-1 is produced by activated infiltrating immunocompetent cells. Lung organ cultures were prepared from unoperated dogs and dogs with rejecting single lung allografts. Incubation of organ cultures from unoperated dogs with ET-1 (10(-9) to 10(-7) M)) increased positive staining for proliferation cell nuclear antigen (PCNA) in lung parenchyma. PCNA staining was not decreased by the endothelin-A antagonist BQ123 (10(-6) M). In addition, immunostaining for endothelin-B receptors was present in sections of unoperated but not rejecting lungs. PCNA staining in lung cultures from rejecting allotransplanted dogs was significantly greater than that from unoperated dogs. Positive immunohistochemical staining for ET-1 was found in mononuclear cells infiltrating rejecting transplanted lungs. In conclusion, exogenous ET-1 is mitogenic in lung organ cultures through receptors other than endothelin-A. Proliferation in rejecting transplanted lungs is increased compared with unoperated lungs. Mononuclear cells may be a source of endothelin-1 in the rejecting lung. ET-1, therefore could, in synergism with other cytokines, contribute to acute and chronic pathological changes seen in pulmonary rejection.  相似文献   
928.
PURPOSE: The authors reviewed their experience with total conjunctival flaps (TCF) and partial conjunctival flaps (PCF) for the past 5 years in 61 patients. METHODS: Forty-eight patients had TCF and 13 had PCF. Diagnoses for surgery included severe bullous keratopathy for chronic graft failure (not candidates for keratoplasty) (19), herpes zoster ophthalmicus (7), chronic ulcerative keratitis (14), neurotrophic keratitis (2), and herpes simplex keratitis (9). RESULTS: There were seven complications. Four flap retractions occurred in the TCF group, requiring resuturing in two. Three complications occurred in the PCF group. One patient had two flap retractions and recurrent ulceration, requiring tarsorrhaphy. One patient with PCF suffered a perforation after flap retraction, necessitating penetrating keratoplasty. CONCLUSION: The authors believe conjunctival flaps are underused and should be considered seriously for bullous keratopathy, neurotrophic keratitis, recalcitrant keratitis, and persistent nonhealing epithelial defects.  相似文献   
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