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1.
M. K. Chandrashekaran G. Marimuthu R. Subbaraj P. Kumarasamy M. S. Ramkumar K. Sripathi 《Journal of biosciences》1991,16(3):97-101
Several bodily functions in humans vary on a 24 h pattern and most of these variations persist with a circadian period ofca 25 h when subjects are studied under conditions of social and temporal isolation. We report in this paper that the estimates
of short time intervals (TE) of 2 h are strongly coupled to the circadian rhythm in sleepwakefulness. There is a linear correlation
between the number of hours humans stay awake (α) and their estimation of 2 h intervals. The coupling of TE to α appears to
obtain only under conditions of physical well-being. 相似文献
2.
A simple and reproducible method for the tritium labeling of small amounts of proteins prior to analysis under denaturing conditions on polyacrylamide slab gels is described. The method involves the in vitro labeling of proteins by reductive methylation using formaldehyde and high specific activity [3H]potassium borohydride. Labeled proteins were detected by fluorography after fractionation on polyacrylamide slab gels in the presence of sodium dodecylsulfate. The overall procedure allows the analysis and molecular weight estimation of submicrogram quantities of protein. 相似文献
3.
S. Justin Carlus Saumya Sarkar Sandeep Kumar Bansal Vertika Singh Kiran Singh Rajesh Kumar Jha Nirmala Sadasivam Sri Revathy Sadasivam P. S. Gireesha Kumarasamy Thangaraj Singh Rajender 《PloS one》2016,11(3)
Background
Optimum efficiency of the folate pathway is considered essential for adequate ovarian function. 677 C>T substitution in the 5, 10-methylene tertrahydrofolatereductase (MTHFR) gene compromises activity of the MTHFR enzyme by about 50%. The significance of correlation between 677C>T substitution and PCOS remains dubious due to the low power of published studies.Methods and Results
We analyzed MTHFR 677 C>T site in ethnically two different PCOS case-control groups (total 261 cases and 256 controls) from India. The data analysis revealed a lack of association between this polymorphism and PCOS [OR = 1.11 (95%CI = 0.71–1.72), P = 0.66]. Group-wise analysis on the basis of ethnicity also revealed no association in any of the ethnic groups [Indo-Europeans, P = 1; Dravidians, P = 0.70]. Homocysteine levels did not differ significantly between cases (15.51 μmol/L, SD = 2.89) and controls (15.89 μmol/L, SD = 2.23). We also undertook a meta-analysis on 960 cases and 1028 controls, which suggested a significant association of the substitution with PCOS in the dominant model of analysis (OR = 1.47 (95%CI = 1.04–2.09), P = 0.032]. Trial sequential analysis corroborated findings of the traditional meta-analysis. However, we found that the conclusions of meta-analysis were strongly influenced by studies that deviated from the Hardy Weinberg equilibrium. A careful investigation of each study and a trial sequential analysis suggested that 677 C>T substitution holds no clinical significance in PCOS in most of the populations.Conclusion
In conclusion, MTHFR 677 C>T polymorphism does not affect PCOS risk in India. The association seen in the meta-analysis is due to an outlier study and studies showing deviation from the Hardy Weinberg equilibrium. 相似文献4.
5.
Chokkalingam Uvarani Karuppannan Arumugasamy Kumarasamy Chandraprakash Mathan Sankaran Athar Ata Palathurai Subramaniam Mohan 《化学与生物多样性》2015,12(3):358-370
Phytochemical investigation of the CHCl3 fraction of Swertia corymbosa resulted in the isolation of a new 3‐allyl‐2,8‐dihydroxy‐1,6‐dimethoxy‐9H‐xanthen‐9‐one ( 1 ), along with four known xanthones, gentiacaulein ( 3 ), norswertianin ( 4 ), 1,3,6,8‐tetrahydroxyxanthone ( 5 ), and 1,3‐dihydroxyxanthone ( 6 ). Structure of compound 1 was elucidated with the aid of IR, UV, NMR, and MS data, and chemical transformation via new allyloxy xanthone derivative ( 2 ). Compounds 1 – 6 exhibited various levels of antioxidant and anti‐α‐glucosidase activities. Absorption and fluorescence spectroscopic studies on 1 – 6 indicated that these compounds could interact with calf thymus DNA (CT‐DNA) through intercalation and with bovine serum albumin (BSA) in a static quenching process. Compound 1 was found to be significantly cytotoxic against human cancer cell lines HeLa, HCT116, and AGS, and weakly active against normal NIH 3T3 cell line. 相似文献
6.
Kawsar R. Talaat Subash Babu Pradeep Menon N. Kumarasamy Jabin Sharma Jeeva Arumugam Kalaivani Dhakshinamurthy Ramalingam Srinivasan S. Poongulali Wenjuan Gu Michael P. Fay Soumya Swaminathan Thomas B. Nutman 《PLoS neglected tropical diseases》2015,9(3)
BackgroundThe disease course of human immunodeficiency virus (HIV) is often altered by existing or newly acquired coincident infections.Conclusions/SignificanceWe were unable to find a significant effect of W. bancrofti infection or its treatment on HIV clinical course or surrogate markers of HIV disease progression though we recognized that our study was limited by the smaller than predicted sample size and by the use of ART in half of the patients. Treatment of W. bancrofti coinfection in HIV positive subjects (as is usual in mass drug administration campaigns) did not represent an increased risk to the subjects, and should therefore be considered for PLWHA living in W. bancrofti endemic areas.
Trial Registration
ClinicalTrials.gov NCT00344279相似文献7.
Deepa Selvi Rani Perundurai S. Dhandapany Pratibha Nallari Periyasamy Govindaraj Lalji Singh Kumarasamy Thangaraj 《Mitochondrion》2010,10(2):166-173
Mutations in PTPN11 gene was responsible for ~50% of the Noonan syndrome (NS), however, we did not find any mutation in PTPN11 in any of seven NS patients analysed. Whereas, the complete mtDNA sequencing revealed 146 mutations, of which five, including one heteroplasmic (A11144R; Thr → Ala) non-synonymous mutation, were novel and exclusively observed in NS patients. Interestingly all the seven probands and their maternal relatives were clustered under a major haplogroup R and its novel sub-haplogroups (R7b1b, R30a1, R30c, T2b7, U9a1) exclusive in NS, therefore we strongly suggest that these haplogroups may influence NS in South Indian populations. 相似文献
8.
Jong‐Rok Jeon Eun‐Ju Kim Kumarasamy Murugesan Hyo‐Keun Park Young‐Mo Kim Jung‐Hee Kwon Wang‐Gi Kim Ji‐Yeon Lee Yoon‐Seok Chang 《Microbial biotechnology》2010,3(3):324-335
Laccase efficiently catalyses polymerization of phenolic compounds. However, knowledge on applications of polymers synthesized in this manner remains scarce. Here, the potential of laccase-catalysed polymerization of natural phenols to form products useful in hair dyeing was investigated. All 15 tested phenols yielded coloured products after laccase treatment and colour diversity was attained by using mixtures of two phenolic monomers. After exploring colour differentiation pattern of 120 different reactions with statistical regression analysis, three monomer combinations, namely gallic acid and syringic acid, catechin and catechol, and ferulic acid and syringic acid, giving rise to brown, black, and red materials, respectively, were further characterized because such colours are commercially important for grey hair dyeing. Selected polymers could strongly absorb visible light and their hydrodynamic sizes ranged from 100 to 400 nm. Analyses of enzyme kinetic constants, liquid chromatography and electrospray ionization-mass spectrometry (ESI-MS) coupled with collision-induced dissociation MS/MS indicate that both monomers in reactions involving catechin and catechol, and ferulic acid and syringic acid, are coloured by heteropolymer synthesis, but the gallic acid/syringic acid combination is based on homopolymer mixture formation. Comparison of colour parameters from these three reactions with those of corresponding artificial homopolymer mixtures also supported the idea that laccase may catalyse either hetero- or homo-polymer synthesis. We finally used selected materials to dye grey hair. Each material coloured hair appropriately and the dyeing showed excellent resistance to conventional shampooing. Our study indicates that laccase-catalysed polymerization of natural phenols is applicable to the development of new cosmetic pigments. 相似文献
9.
Rajagopal Subramanyam Craig Jolley Balakumar Thangaraj Sreedhar Nellaepalli Andrew N. Webber Petra Fromme 《Planta》2010,231(4):913-922
The effect of high salt concentration (100 mM NaCl) on the organization of photosystem I-light harvesting complex I supercomplexes
(PSI-LHCI) of Chlamydomonas reinhardtii was studied. The electron transfer activity was reduced by 39% in isolated PSI-LHCI supercomplexes. The visible circular
dichroism (CD) spectra associated with strongly coupled chlorophyll (Chl) dimers were reduced in intensity, indicating that
pigment–pigment interactions were disrupted. This data is consistent with results from fluorescence streak camera spectroscopy,
which suggest that red-shifted pigments in the PSI-LHCI antenna had been lost. Denaturing gel electrophoresis and immunoblot
analysis reveals that levels of the PSI reaction center proteins PsaD, PsaE and PsaF were reduced due to salt stress. PsaE
is almost completely absent under high salt conditions. It is known that the membrane-extrinsic subunits PsaD and E form the
ferredoxin-docking site. Our results indicate that the PSI-LHCI supercomplex is damaged by reactive oxygen species at high
salt concentration, with particular impact on the ferredoxin-docking site and the PSI-LHCI interface. 相似文献
10.
Zerjal T Pandya A Thangaraj K Ling EY Kearley J Bertoneri S Paracchini S Singh L Tyler-Smith C 《Human genetics》2007,121(1):137-144
The caste system has persisted in Indian Hindu society for around 3,500 years. Like the Y chromosome, caste is defined at
birth, and males cannot change their caste. In order to investigate the genetic consequences of this system, we have analysed
male-lineage variation in a sample of 227 Indian men of known caste, 141 from the Jaunpur district of Uttar Pradesh and 86
from the rest of India. We typed 131 Y-chromosomal binary markers and 16 microsatellites. We find striking evidence for male
substructure: in particular, Brahmins and Kshatriyas (but not other castes) from Jaunpur each show low diversity and the predominance
of a single distinct cluster of haplotypes. These findings confirm the genetic isolation and drift within the Jaunpur upper
castes, which are likely to result from founder effects and social factors. In the other castes, there may be either larger
effective population sizes, or less strict isolation, or both.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.
Tatiana Zerjal and Arpita Pandya contributed equally to this work. 相似文献