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991.
从1977年2月~1985年12月共收治了流行性出血热患者209例,其中死亡30例、病死率为14.13%。本文对这30例死因进行分析,9例死于休克期;16例死于少尿期;2例死于移行期;3例死于多尿期。进行性肾衰为本病死亡的主要原因(占70%)。为了降低流行性出血热死亡率,对控制肾衰及其并发症的预防性治疗极为重要。文中对本组死亡病例的经验教训和防止中枢神经系统并发症问题进行了探讨。 相似文献
992.
993.
A retrospective study of flow cytometric measurements on paraffin embedded tumor specimens from 188 patients with bladder tumor was made and the results were analyzed in combination with the morphological changes of bladder tumors. It was found that the DNA ploidy pattern, degree of infiltration and the multiplicity of bladder tumor were closely related with tumor recurrence, among which the DNA ploidy pattern was most significant. In the aneuploid bladder tumors the recurrent rate and mean annual recurrent frequency were 76.7% and 1.46, and those in the diploid bladder tumors were 18.7% and 0.33 respectively. Aneuploidy was the most indicative parameter in the recurrence of bladder tumor. In addition, according to the DNA ploidy pattern and DNA index, the aneuploid tumors in our group were divided into 4 types, namely, tetraploid tumors, non-euploid tumors with DNA index less than or equal to 1.5, non-euploid tumors with DNA index greater than 1.5 and two-aneuploid tumors. The results showed that the recurrent rate of tetraploid tumor was relatively low and it became higher and higher in the following order, e.g., non-euploid tumors with DNA index less than or equal to 1.5, non-euploid tumors with DNA index greater than 1.5 and two-aneuploid tumors, indicating that there were different biological behaviors in tumors with different ploidy patterns. Finally, the relationship between DNA ploidy pattern and tumor metastasis was also discussed. 相似文献
994.
本实验以定量细胞化学的方法对种60Coy射线8Gy全身-次照射后第6天小鼠腹腔巨噬细胞的变化和5-羟色胺(5-HT)的辐射防护作用进行了观察.发现照射后第6天巨噬细胞吞噬消化鸡红细胞的能力明显低于对照组(P相似文献
995.
996.
The effect of rapamycin (RAPA) on both host-versus-graft (HVG) and graft-versus-host (GVH) immune responses was examined in small bowel transplant models using strongly histoincompatible donor-recipient combinations. Normal Wistar Furth (WFu; RT-1u) recipients rejected Buffalo (BUF; RT-1b) small bowel allografts within a mean survival time (MST) of 10.5 +/- 0.5 days. Administration of RAPA (0.8 mg/kg) by continuous intravenous infusion for 14 days via an osmotic pump prolonged graft survival to 25.0 +/- 4.6 days (P = 0.01). In a second strain combination, the 12.5 +/- 2.2 day survival of Brown Norway (BN; RT-1n) small bowel allografts in Lewis (RT-1l) recipients was prolonged to 21.6 +/- 2.0 and 28.5 +/- 2.8 days by 14 days of i.v. RAPA at doses of 0.8 and 1.6 mg/kg, respectively. In this model RAPA is five times more effective than cyclosporine, which at 4.0 mg/kg prolongs BN small bowel allografts in Lewis recipients to 21.6 +/- 6.3. To isolate HVG and GVH immune responses, (BN x Lewis)F1 hybrid rats served as the graft donor or host, respectively. In the HVG model, (BN x Lewis)F1 small bowel allografts, which were rejected by normal Lewis recipients at 12.2 +/- 3.6 days, were prolonged to 40.8 +/- 5.8 days (P = 0.001) by RAPA (0.8 mg/kg x 14 days). In the GVH model, the ability of Lewis small bowel allografts to produce severe GVH disease in untreated (BN x Lewis)F1 recipients at 12.3 +/- 2.8 days was delayed to 21.3 +/- 5.2 days by 0.8 mg/kg RAPA (P = 0.025). Thus, RAPA protects small bowel allografts more effectively against HVG than GVH immune responses. 相似文献
997.
998.
Nucleotide polymorphism in colicin E1 and Ia plasmids from natural isolates of Escherichia coli. 总被引:2,自引:0,他引:2
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M A Riley Y Tan J Wang 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(23):11276-11280
We examined DNA sequence polymorphism for the colicin gene clusters of seven ColE1 and six ColIa plasmids obtained from natural isolates of Escherichia coli. These gene clusters harbor levels of nucleotide diversity ranging from 0.006 (ColIa) to 0.054 (ColE1). This level of diversity is similar to that observed for chromosomally encoded E. coli genes. However, the variance associated with these estimates is severalfold higher for the plasmid-encoded genes. This increased variance may be due to the differing plasmid population sizes. The pattern of colicin gene cluster polymorphism suggests that the two colicins are evolving in different fashions. ColE1 accumulates polymorphism at an elevated rate in the central domain of the colicin protein, while ColIa polymorphism is distributed evenly along the gene cluster. Comparison of the patterns of divergence between colicin and related proteins of ColIa and Ib and patterns of polymorphism within ColIa suggest that this gene cluster is not evolving in a neutral fashion. These data lend support to the hypothesis that colicin gene clusters may evolve under the influence of diversifying selection. 相似文献
999.
Summary In this study the technique of labelling the cell membrane with DPH fluorescence polarization was used to observe the membrane
fluidity of B lymphocytic cell lines and tonsillar cells from healthy persons; the modulation effect on membrane-fluidity
induced by McAbs against isotypic and idiotypic determinants of IgM from patients with leukemia was studied as well. The expression
of the corresponding isotypic and idiotypic determinants of IgM on the cell membrane was determined. The results show that
the membrane fluidity of leukemic cell lines is remarkably higher than that of tonsillar cells from healthy persons, and McAbs
against isotypic determinants of leukemic IgM can enhance the membrane fluidity of all kinds of cells mentioned above. However,
the anti-idiotypic monoclonal antibody increased only the membrane fluidity of leukemic cell lines. These results indicated
that there was a close relationship between the effect of McAbs on cell membrane fluidity and the expression of corresponding
isotypic and idiotypic determinants of IgM on the cell membrane. 相似文献
1000.
This paper reports the treatment results of 50 symptomatic females who had clinical features of squamous papillae and histologic evidence of koilocytosis. Either a carbon dioxide laser or a single application of trichloroacetic acid (TCA) was used to treat these patients. All of the patients were alternately and prospectively randomized into one of two groups. Twenty-three of the 25 women treated by laser and 10 of the 25 women treated by TCA had resolution of either the symptoms or the vulvar lesions in a follow-up period ranging from six to 22 months. Hence, we were able to control the symptoms and lesions in 92% of the women following initial laser treatment and 40% of the women following a single application of TCA. In addition, cosmetic results were satisfactory, and complications were minimal in the laser-treated group of patients. However, human papillomavirus DNA was still detected three to four weeks after treatment in 24% of the women treated by laser and 64% of the women treated by TCA. Whether they are at a higher risk of recurrence as compared to those without detectable viral DNA remains to be determined. 相似文献