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81.
Sadana R Mittal A Khurana S Singh H Kamboj RC 《Indian journal of biochemistry & biophysics》2003,40(5):315-323
Cathepsin L-like proteinase was purified approximately 1708-fold with 40% activity yield to an apparent electrophoretic homogeneity from goat brain by homogenization, acid-autolysis at pH 4.2, 30-80% (NH4)2SO4 fractionation, Sephadex G-100 column chromatography and ion-exchange chromatography on CM-Sephadex C-50 at pH 5.0 and 5.6. The molecular weight of proteinase was found to be approximately 65,000 Da, by gel-filtration chromatography. The pH optima were 5.9 and 4.5 for the hydrolysis of Z-Phe-Arg-4mbetaNA (benzyloxycarbonyl-L-phenylalanine-L-arginine-4-methoxy-beta-naphthylamide) and azocasein, respectively. Of the synthetic chromogenic substrates tested, Z-Phe-Arg-4mbetaNA was hydrolyzed maximally by the enzyme (Km value for hydrolysis was 0.06 mM), followed by Z-Val-Lys-Lys-Arg-4mbetaNA, Z-Phe-Val-Arg-4mbetaNA, Z-Arg-Arg-4mbetaNA and Z-Ala-Arg-Arg-4mbetaNA. The proteinase was activated maximally by glutathione in conjunction with EDTA, followed by cysteine, dithioerythritol, thioglycolic acid, dithiothreitol and beta-mercaptoethanol. It was strongly inhibited by p-hydroxymercuribenzenesulphonic acid, iodoacetic acid, iodoacetamide and microbial peptide inhibitors, leupeptin and antipain. Leupeptin inhibited the enzyme competitively with Ki value 44 x 10(-9) M. The enzyme was strongly inhibited by 4 M urea. Metal ions, Hg(2+), Ca(2+), Cu(2+), Li(2+), K(+), Cd(2+), Ni(2+), Ba(2+), Mn(2+), Co(2+) and Sn(2+) also inhibited the activity of the enzyme. The enzyme was stable between pH 4.0-6.0 and up to 40 degrees C. The optimum temperature for the hydrolysis of Z-Phe-Arg-4mbetaNA was approximately 50-55 degrees C with an activation energy Ea of approximately 6.34 KCal mole(-1). 相似文献
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Kheirolomoom A Satpathy GR Török Z Banerjee M Bali R Novaes RC Little E Manning DM Dwyre DM Tablin F Crowe JH Tsvetkova NM 《Cryobiology》2005,51(3):290-305
In a previous report [Z. T?r?k, G. Satpathy, M. Banerjee, R. Bali, E. Little, R. Novaes, H. Van Ly, D. Dwyre, A. Kheirolomoom, F. Tablin, J.H. Crowe, N.M. Tsvetkova, Preservation of trehalose loaded red blood cells by lyophilization, Cell Preservation Technol. 3 (2005) 96-111.], we presented a method for preserving human red blood cells (RBCs) by loading them with trehalose and then freeze-drying. We have now improved that method, based on the discovery that addition of phospholipid vesicles to the lyophilization buffer substantially reduces hemolysis of freeze-dried RBCs after rehydration. The surviving cells synthesize 2,3-DPG, have low levels of methemoglobin, and have preserved morphology. Among the lipid species we studied, unsaturated PCs were found to be most effective in suppressing hemoglobin leakage. RBC-vesicle interactions depend on vesicle size and structure; unilamellar liposomes with average diameter of less than 300 nm were more effective in reducing the hemolysis than multilamellar vesicles. Trehalose loaded RBCs demonstrated high survival and low levels of methemoglobin during 10 weeks of storage at 4 degrees C in the dry state when lyophilized in the presence of liposomes. 相似文献
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Do mental health professionals use diagnostic classifications the way we think they do? A global survey
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Michael B. First Tahilia J. Rebello Jared W. Keeley Rachna Bhargava Yunfei Dai Maya Kulygina Chihiro Matsumoto Rebeca Robles Anne‐Claire Stona Geoffrey M. Reed 《World psychiatry》2018,17(2):187-195
We report on a global survey of diagnosing mental health professionals, primarily psychiatrists, conducted as a part of the development of the ICD‐11 mental and behavioural disorders classification. The survey assessed these professionals' use of various components of the ICD‐10 and the DSM, their attitudes concerning the utility of these systems, and usage of “residual” (i.e., “other” or “unspecified”) categories. In previous surveys, most mental health professionals reported they often use a formal classification system in everyday clinical work, but very little is known about precisely how they are using those systems. For example, it has been suggested that most clinicians employ only the diagnostic labels or codes from the ICD‐10 in order to meet administrative requirements. The present survey was conducted with clinicians who were members of the Global Clinical Practice Network (GCPN), established by the World Health Organization as a tool for global participation in ICD‐11 field studies. A total of 1,764 GCPN members from 92 countries completed the survey, with 1,335 answering the questions with reference to the ICD‐10 and 429 to the DSM (DSM‐IV, DSM‐IV‐TR or DSM‐5). The most frequent reported use of the classification systems was for administrative or billing purposes, with 68.1% reporting often or routinely using them for that purpose. A bit more than half (57.4%) of respondents reported often or routinely going through diagnostic guidelines or criteria systematically to determine whether they apply to individual patients. Although ICD‐10 users were more likely than DSM‐5 users to utilize the classification for administrative purposes, other differences were either slight or not significant. Both classifications were rated to be most useful for assigning a diagnosis, communicating with other health care professionals and teaching, and least useful for treatment selection and determining prognosis. ICD‐10 was rated more useful than DSM‐5 for administrative purposes. A majority of clinicians reported using “residual” categories at least sometimes, with around 12% of ICD‐10 users and 19% of DSM users employing them often or routinely, most commonly for clinical presentations that do not conform to a specific diagnostic category or when there is insufficient information to make a more specific diagnosis. These results provide the most comprehensive available information about the use of diagnostic classifications of mental disorders in ordinary clinical practice. 相似文献
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Summary and Conclusion The processing conditions has a pronounced effect on the pellet properties. Drying conditions influenced the mean size and
the drug release of the pellets. Because of the shrinking of the pellets upon drying at higher temperatures, the pellets also
showed increased densities. Freeze drying almost prevented shrinking and thus led to the highest drug release. With an increase
in the temperature of drying, the drug release rate decreased.
Both spheronization time and spheronization speed affected the shapes of pellets, and the changes in shapes then affected
the pellet flow properties. Within the studied range, the circularity of the pellets was affected more by the spheronization
time than by the spheronization speed. Drying conditions influenced pellet friability, which decreased with an increase in
drying temperature, indicating the formation of more dense structures at higher temperatures. The same result was obtained
with spheronization time. With an increase in spheronization time, the friability decreased, because of the formation of more
compact masses at higher spheronization time. Mean size was not affected by spheronization time or spheronization speed.
Published: March 9, 2007 相似文献
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Rachna Kaushik Rachna Kaushik Rachna Kaushik Rachna Kaushik Rachna Kaushik Rachna Kaushik 《PLoS biology》2007,5(6):e146
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Dengue virus-specific suppressor T cells: current perspectives 总被引:2,自引:0,他引:2
Chaturvedi UC Shrivastava R Tripathi RK Nagar R 《FEMS immunology and medical microbiology》2007,50(3):285-299
Dengue virus was the first microorganism that was shown to induce generation of antigen-specific suppressor T (TS) cells in mice. The cascade of the three generations of TS cells (TS1, TS2, TS3) and their secretary products, the suppressor factors (SF1, SF2), was delineated. The TS pathway was proposed to be protective through inhibition of the production of enhancing antibody, which may enhance the severity of dengue disease. The currently second most favoured mechanism of severe dengue disease is the 'cytokine tsunami'. During the last decade, suppressor/regulatory T cells have been studied in greater detail using modern techniques in various diseases, including viral infections. This brief review discusses the role of dengue-specific suppressor T cells in protection and/or induction of severe dengue disease in view of our current understanding of suppressor/regulatory T cells. 相似文献
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The present investigation aimed at formulation, performance evaluation, and stability studies of new vesicular drug carrier
system protransfersomes for transdermal delivery of the contraceptive agent, levonorgestrel. Protransfersome gel (PTG) formulations
of levonorgestrel were prepared and characterized for vesicle shape, size, entrapment efficiency, turbidity, and drug permeation
across rat skin and were evaluated for their stability. The system was evaluated in vivo for biological assay of progestational
activity including endometrial assay, inhibition of the formation of corpora lutea, and weight gain of uterus. The effects
of different formulation variables (type of alcohol, type and concentration of surfactant) on transdermal permeability profile
were assessed. The optimized PTG formulation showed enhanced in vitro skin permeation flux of 15.82±0.37 μg/cm2/hr as compared to 0.032±0.01 μg/cm2/hr for plain drug solution. PTG also showed good stability and after 2 months of storage there was no change in liquid crystalline
nature, drug content, and other characteristic parameters. The peak plasma concentration of levonorgestrel (0.139±0.05 μg/mL)
was achieved within 4 hours and maintained until 48 hours by a single topical application of optimized PTG formulation. In
vivo performance of the PTG formulation showed increase in the therapeutic efficacy of drug. Results indicated that the optimized
protransfersomal formulation of levonorgestrel had better skin permeation potential, sustained release characteristic, and
better stability than proliposomal formulation. 相似文献