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41.
I. A. Vinogradova A. V. Bukalev M. A. Zabezhinski A. V. Semenchenko V. Kh. Khavinson V. N. Anisimov 《Bulletin of experimental biology and medicine》2008,145(4):472-477
Exposure of male rats to permanent or natural illumination of North-Western Russia accelerated their death in comparison with
animals exposed to standard (12 h) light. Permanent illumination promoted the development of spontaneous tumors in comparison
with the standard photoregimen. Injection of epithalone (synthetic Ala-Glu-Asp-Gly peptide; subcutaneously 0.1 μg/rat 5 times
a week from the age of 4 months until natural death) virtually did not change the mean lifespan of male rats, but was associated
with a significant (p<0.05) normalization of population aging rate and hence, time of mortality rate doubling in groups exposed to natural or constant
illumination. Epithalone injected to rats exposed to any photoregimen significantly inhibited the development of spontaneous
tumors, primarily testicular leydigomas and leukemias.
__________
Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 145, No. 4, pp. 455–460, April, 2008 相似文献
42.
目的探讨一氧化氮合酶3(nitric oxide synthase 3,NOS3)基因第4内含子27bp数目可变串联重复序列(variable number of tandem repeat,VNTR)多态性和第7外显子894(G/T)多态性与复发性早期自然流产(recurrent early spontaneous abortion,RESA)的相关性。方法选取140例RESA患者和140名健康妇女,应用聚合酶链反应-琼脂糖凝胶电泳法检测NOS3基因第4内含子VNTR多态性,聚合酶链反应-限制性片段长度多态性分析技术检测第7外显子894(G/T)多态性。结果RESA组aa ba基因型频率和a等位基因频率与正常对照组相比差异有统计学意义(χ2=4.51,P<0.05;χ2=4.29,P<0.05)。与bb基因型相比,携带a等位基因的妇女与RESA显著相关(OR为1.8,95%CI:1.04~3.24)。RESA组TT GT基因型频率和T等位基因频率与正常对照组相比差异无统计学意义(χ2=1.16,P>0.05;χ2=1.12,P>0.05)。与GG基因型相比,携带T等位基因的妇女与RESA无相关。结论NOS3基因第4内含子27bp数目可变的串联重复序列多态性与复发性自然流产密切相关,NOS3基因第7外显子894G/T多态性与RESA无明显相关性,a等位基因是RESA重要的遗传易感基因。 相似文献
43.
目的研究藿香正气片增强镇静催眠药对小鼠的镇静催眠作用.为临床增添了一个中西药结合的镇静催眠合剂提供药理依据.方法应用抖笼换能器法观察藿香正气片对小鼠的自发活动的影响.由此观察藿香正气片与镇静催眠药的协同作用.测定藿香正气片与镇静催眠药对小鼠的入睡时间及睡眠持续时间的作用.两个实验均分成四组,生理水组、藿香正气片组、安定组、安定+藿香正气片组.结果1.对小鼠自发活动的影响.(1)藿香正气片组与生理盐水组比较,具有极显著性差异(P<0.01).(2)安定组与安定+藿香正气片组比较具有显著性差异(P<0.05).2.藿香正气片增强镇静催眠药对小鼠的睡眠作用.(1)藿香正气片组与生理盐水组比较具有显著性差异(P<0.05).(2)藿香正气片+安定组与安定组比较具有极显著性差异(P<0.01).结论藿香正气片与安定合用对镇静及催眠确有协同作用. 相似文献
44.
45.
Comparison of spontaneous mutation spectra derived from different transgenic constructs can provide valuable insights for interpreting the mechanisms of spontaneous mutation. In this study, spontaneous mutation frequencies and spectra of the lacI transgene are compared in the liver of C57BL/6, B6C3F1, and BC-1 mice and F344 rats. Before correction for clonal expansion, the mutant frequency varied from 2.6 +/- 0.45 to 5.0 +/- 2.4 x 10(-5). Correction for potential clonal expansion reduced the range in mutation frequency to between 2.3 +/- 0.45 and 3.5 +/- 2.0 x 10(-5). There is thus no statistical difference in spontaneous mutation frequency between the different strains and species. G:C --> A:T transitions and to a lesser extent, G:C --> T:A transversions dominate the mutational spectra in all of these animals. In three strains of mice, G:C --> A:T transitions account for 50.7-53.3% of mutation, 81.7-83.8% of which involve CpG sites, whereas G:C --> T:A transversions account for 17.8-32.9% of mutations with 43.2-50.0% found at CpG sites. In rats, G:C --> A:T transitions account for 38.0% of the spectra, 70.0% of which involve CpG sites, whereas G:C --> T:A transversions account for 23.0% of the spectra, 70.0% of which involve CpG sites. The distribution of other classes of mutations is also very similar. We conclude that, despite reports about species and strain differences in induced mutation, spontaneous mutations in the lacI transgene appear to be similar, regardless of genomic location, rodent strain, or species. In addition to insights into spontaneous mutation, this study also provides essential data for comparison with and interpretation of induced mutations. 相似文献
46.
反复自然流产患者血清中封闭抗体的检测 总被引:5,自引:2,他引:5
本文根据病史将反复自然流产(RSA)分类为原发性RSA 及继发性RSA,分别以单向混合淋巴细胞反应封闭试验及补体依赖微量细胞毒试验评价封闭抗体与两类流产的关系。结果发现,原发性RSA主要因封闭抗体缺乏所致;而继发性RSA 无封闭抗体缺乏迹象。因此,尽管原发性RSA 与继发性RSA 临床表现类似,但其免疫学病因及发病机理可能不同。 相似文献
47.
48.
A. P. C. Yim 《Surgical endoscopy》1995,9(9):1013-1016
We prospectively studied thoracoscopic suturing of apical bullae in the management of primary spontaneous pneumothorax. From June 1993 to July 1994, we performed 29 such procedures in 27 patients. (All males ranging in age from 15 to 40.) Bullae less than 2 cm in diameter were imbricated (18), while larger bullae were resected and repaired with 3/0 polypropylene suture (11). Postoperative morbidity was minimal. Averaged postoperative parenteral narcotic (Pethidine) requirement was 88 mg, chest drainage was 1.7 (range 1–4) days, and hospital stay was 2.5 (range 1–7) days. There was no recurrence after a mean follow-up of 10 months. In comparison, 32 patients prior to this study period underwent staple resection of apical bulla. Demographic data in the two groups were similar. Averaged Pethidine requirement in the staple group was 98 mg, chest drainage was 1.8 (range 1–5) days, and hospital stay was 2.6 (range 1–7) days. There was no statistical difference in the two groups with respect to pain medication, chest drainage, or hospital stay. The technique of thoracoscopic suturing can be easily acquired. In view of the high cost of staple-cutters, endoscopic suturing should be considered as a viable alternative to staple resection of apical bullae in the treatment of primary spontaneous pneumothorax.Presented in part at the 4th World Congress of Endoscopic Surgery, Kyoto, Japan, June 16–19, 1994 [6] 相似文献
49.
Kwak JY Beer AE Kim SH Mantouvalos HP 《American journal of reproductive immunology (New York, N.Y. : 1989)》1999,41(1):91-98
PROBLEM: Placental lesions of 71 women with documented recurrent spontaneous abortions of unknown etiology were evaluated using immunohistochemical staining. METHOD OF STUDY: Placental tissue blocks (less than 12 weeks gestation) from prior pregnancy losses were obtained, recut, and analyzed utilizing monoclonal antibody to identify the trophoblast (cytokeratin 8/18) and natural killer (NK) cells (CD57) at the implantation site. The following features were evaluated: trophoblast invasion pattern; syncytium formation; vasculitis and thromboembolism of decidual vessels; decidual inflammation; decidual necrosis; fibrin deposition at the decidual necrosis site; mononuclear-cell infiltration in villi and intervillous space; perivillous fibrin deposition; trophoblast morphology; and quantitation of CD57+ NK cells within the decidual tissue near the implantation site. Controls consisted of 20 healthy women with no history of recurrent pregnancy losses, who had their pregnancies electively terminated. RESULTS: Of the women studied, 29.6% demonstrated elevated CD57+ NK cells at the implantation site (P = 0.030), 54.1% had inadequate cytotrophoblast invasion depth (P = 0.000), 44.1% demonstrated inadequate syncytium formation (P = 0.004), and 33.9% presented thromboembolism in decidual vessels (P = 0.025). CONCLUSION: Some women with recurrent spontaneous abortions demonstrate abnormal placental lesions at the implantation site. Immunopathologic evaluation of the placental implantation site that terminated in a spontaneous abortion may reveal the immunopathogenesis of previous pregnancy losses. 相似文献
50.
Background: Recent data suggest that children have a higher incidence of recurrence than adults after nonoperative treatment of primary
spontaneous pneumothorax (PSP). Video-assisted thoracoscopic surgery (VATS) allows efficacious therapy with significantly
less morbidity. We attempt to define the most cost-effective clinically efficacious strategy using VATS to manage pediatric
PSP.
Methods: We retrospectively reviewed all admissions to a tertiary care children's hospital for PSP between January 1, 1991 and June
30, 1996.
Results: Fifteen children had 29 primary or recurrent PSPs. Mean patient age was 14.8 ± 1.1 years, boy–girl ratio 4:1, median body
mass index 18 (normal, 20–25), and 67% of pneumothoraces left sided. All patients were managed initially nonoperatively: 14
with tube thoracostomy drainage and 1 with oxygen alone. Of the children initially managed nonoperatively, 57% had a recurrent
pneumothorax, and 50% of these patients eventually developed contralateral pneumothoraces. Nonoperative treatment for recurrence
resulted in a 75% second recurrence rate. In contrast, eight children who underwent operative management had a 9% incidence
of recurrence. The total for charges accrued in treating 29 pneumothoraces in these 15 patients was approximately $315,000.
In the same population, the estimated charges for initial nonoperative therapy followed by bilateral thoracoscopy after a
single recurrence would be $230,000.
Conclusions: A cost-effective treatment strategy for pediatric primary spontaneous pneumothorax is tube thoracostomy at first presentation,
followed by VATS with thoracoscopic bleb resection and pleurodesis for patients who experience recurrent pneumothorax.
Received: 15 May 1998/Accepted: 15 January 1999 相似文献