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排序方式: 共有2132条查询结果,搜索用时 15 毫秒
21.
In an attempt to identify potentially lithogenic proteins, a detergent soluble extract of human renal calculi was used to produce a unique monoclonal antibody. The monoclonal antibody was found to detect the presence of a specific epitope in 77% of individually extracted kidney stones from our patients' stone bank at The Long Island Kidney Stone Unit, State University of New York, Stony Brook. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis, immunoprecipitation, and Western Blot analysis revealed this monoclonal antibody to be specific to a protein of 83,000 dalton molecular weight. A secondary source of protein reactive to the monoclonal antibody was subjected to enzyme kinetic studies, those studies suggested that the 83,000 dalton protein is a member of the protein-glutamine gammaglutamyltransferase (transglutaminase) family of enzymes. It was not determined in the present investigation whether a member of this family of enzymes initiates or is necessary for lithiasis. 相似文献
22.
Leonid Roytblat Simon Gelman Todd Henderson Dale Parks 《Journal canadien d'anesthésie》1991,38(1):121-128
The hypothesis that histamine receptor (H1 and H2) blockade beneficially affects the hepatic oxygen supply-demand relationship was tested during experiments performed on 13 miniature pigs. Hepatic arterial and portal blood flows were measured with electromagnetic flowmeters. Cardiac output was determined by thermodilution. H1 and H2 receptor blockade was achieved with promethazine, 5 mg.kg-1 and cimetidine 30 mg.kg-1 IV, respectively. The study demonstrated no significant effect of H1 and H2 receptor blockade on hepatic oxygen uptake and no noticeable effects of cimetidine on hepatic circulation. However, promethazine decreased total hepatic blood flow, primarily by decreasing portal blood flow; this resulted in an increase in oxygen extraction as reflected in a decreased oxygen content in hepatic venous blood. The results reject the posed hypothesis: H1 receptor antagonist promethazine decreased, while H2 receptor antagonist cimetidine did not affect hepatic blood flow and oxygen supply; hepatic oxygen demand remained unaffected during H1 and H2 receptor blockade. 相似文献
23.
RuthKandel KevanL.Hartshorn 《中国处方药》2004,(3):34-35
流感病毒感染是致病和死亡的重要原因之一。而且,全球再次爆发流感大流行的可能性依然存在。现在已经有了许多新的有效办法预防和治疗流感。预防流感最有效的办法是接种疫苗。新的疫苗方法在利用保守的流感病毒成分或病毒DNA成分方面正取得进展。 相似文献
24.
Jacky Govrin-Yehudain Leonid Kogan Hector I Cohen Tzipora C Falik-Zaccai 《The Journal of adolescent health》2004,35(2):151-155
OBJECTIVE: Juvenile (virginal) hypertrophy of the breast (JHB) is a relatively rare condition leading to gigantomastia in peripubertal females. The pathology is limited usually to the breast, with otherwise normal growth and development and without any other deformities. The rapid growth of the breast (bilateral or unilateral) in adolescent girls leads to significant physical and psychological difficulties. This gigantomastia is treated surgically by breast reduction or mastectomy and its modification. Familial JHB was described only once in the literature, and its etiology is unknown. RESULTS: We report here on a familial pattern of juvenile hypertrophy of the breast accompanied by congenital anonychia. To the best of our knowledge, this is the first report of such a presentation. Our study dealt with four members of the same family, related through their fathers, enduring congenital anonychia of hands and feet with no functional limitation and who showed rapid uncontrolled breast enlargement in prepubertal age. This was severe enough to cause the curtailment of their social activity and cessation of schooling. The mothers of all four patients had normal breasts and nails, whereas their fathers had anonychia. The genetic basis for the association between the two clinical findings is yet to be determined. CONCLUSION: The four girls underwent breast reduction surgery. 相似文献
25.
Alexey V. Osipov Vladislav G. Starkov Elena V. Ryumina Leonid V. Kozlov Yvon Doljansky Yuri N. Utkin 《Toxicon》2005,46(4):394-403
Two forms of complement-depleting cobra venom factor (CVFm1 and CVFm2), possessing molecular masses of 142.6 kDa (CVFm1) and 143.1 kDa (CVFm2), according to MALDI mass-spectrometry, were isolated from the Naja melanoleuca cobra venom. As shown by polyacrylamide gel electrophoresis in the presence of SDS, both forms similarly to factor from the Naja kaouthia cobra venom (CVFk) consist of three polypeptide chains with molecular masses of about 70, 50, and 30 kDa, the two large subunits being glycosylated. As determined by MALDI mass-spectrometry, 30 kDa subunits of CVFm1 and CVFm2 have considerably different finger-prints of tryptic digests that suggests differences in their amino acid sequences. A study of activity in vivo has shown no significant differences in C3 consumption by CVFm1, CVFm2 and CVFk in mouse blood. However, as shown by an immunoassay method, they differ in their ability to activate the complement system via C3 conversion, the ratio of these activities for CVFm1:CVFm2:CVFk being 2.5:1.6:1. Kinetic studies using a hemolytic test showed that complement depletion by CVFm1 is faster than that by CVFm2. Thus, for the first time the presence in a single venom of two forms of CVF differing by both amino acid sequence and biological activity has been shown. 相似文献
26.
27.
Aleksandr Kolchin Dmitrii Shuleiko Mikhail Martyshov Aleksandra Efimova Leonid Golovan Denis Presnov Tatiana Kunkel Victoriia Glukhenkaya Petr Lazarenko Pavel Kashkarov Stanislav Zabotnov Sergey Kozyukhin 《Materials》2022,15(10)
Ge2Sb2Te5 (GST225) looks to be a promising material for rewritable memory devices due to its relatively easy processing and high optical and electrophysical contrast for the crystalline and amorphous phases. In the present work, we combined the possibilities of crystallization and anisotropic structures fabrication using femtosecond laser treatment at the 1250 nm wavelength of 200 nm thin amorphous GST225 films on silicon oxide/silicon substrates. A raster treatment mode and photoexcited surface plasmon polariton generation allowed us to produce mutually orthogonal periodic structures, such as scanline tracks (the period is 120 ± 10 μm) and laser-induced gratings (the period is 1100 ± 50 nm), respectively. Alternating crystalline and amorphous phases at the irradiated surfaces were revealed according to Raman spectroscopy and optical microscopy studies for both types of structures. Such periodic modulation leads to artificial optical and electrophysical anisotropy. Reflectance spectra in the near infrared range differ for various polarizations of probing light, and this mainly results from the presence of laser-induced periodic surface structures. On the other hand, the scanline tracks cause strong conductivity anisotropy for dc measurements in the temperature range of 200–400 K. The obtained results are promising for designing new GST225-based memory devices in which anisotropy may promote increasing the information recording density. 相似文献
28.
C. R. Genter II G. A. Geri G. L. Kandel B. M. Wolf 《Documenta ophthalmologica. Advances in ophthalmology》1982,53(1):3-15
Stiles-Crawford functions (SCF's) were measured for both eyes of an albino observer with a marked pendular nystagmus using an eye position monitoring system. Both eyes demonstrated directional sensitivity as revealed by their SCF's. The directional sensitivity of both eyes was less than that of either the foveal or parafoveal region of normal observers. In addition, there was a significant difference between the SCF's for the albino observer's two eyes. Our results suggest that the psychophysical SCF is predominately the result of the orientational distribution of groups of receptors on the retina. 相似文献
29.
Daria Matyushkina Varvara Shokina Polina Tikhonova Valentin Manuvera Dmitry Shirokov Daria Kharlampieva Vasily Lazarev Anna Varizhuk Tatiana Vedekhina Alexander Pavlenko Leonid Penkin Georgij Arapidi Konstantin Pavlov Dmitry Pushkar Konstantin Kolontarev Alexander Rumyantsev Sergey Rumyantsev Lyubov Rychkova Vadim Govorun 《Viruses》2022,14(6)
COVID-19 caused by SARS-CoV-2 is continuing to spread around the world and drastically affect our daily life. New strains appear, and the severity of the course of the disease itself seems to be decreasing, but even people who have been ill on an outpatient basis suffer post-COVID consequences. Partly, it is associated with the autoimmune reactions, so debates about the development of new vaccines and the need for vaccination/revaccination continue. In this study we performed an analysis of the antibody response of patients with COVID-19 to linear and conformational epitopes of viral proteins using ELISA, chip array and western blot with analysis of correlations between antibody titer, disease severity, and complications. We have shown that the presence of IgG antibodies to the nucleoprotein can deteriorate the course of the disease, induce multiple direct COVID-19 symptoms, and contribute to long-term post-covid symptoms. We analyzed the cross reactivity of antibodies to SARS-CoV-2 with own human proteins and showed that antibodies to the nucleocapsid protein can bind to human proteins. In accordance with the possibility of HLA presentation, the main possible targets of the autoantibodies were identified. People with HLA alleles A01:01; A26:01; B39:01; B15:01 are most susceptible to the development of autoimmune processes after COVID-19. 相似文献
30.