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1.
V. Selvakumar P. R. Anbudurai T. Balakumar 《In vitro cellular & developmental biology. Plant》2001,37(2):280-284
Summary A protocol for rapid in vitro propagation using nodal explants obtained from 2-yr-old, field-grown medicinal plants of Plumbago zeylanica L. belonging to the family Plumbaginaceae is described. High frequency bud break and fast development of shoots were induced
on Murashige and Skoog's basal medium supplemented with 27.2 μM adenine sulfate +2.46 μM indole-3-butyric acid (IBA). Induction of rooting was achieved by transferring the shoots to the same basal medium containing
4.92 μM IBA. Using our protocol from one twig of P. zeylanica (eight responsive nodes per explant shoot) within a period of 5 mo., eight plantlets could be raised. After a hardening period
of 4 wk, there was a 90% transplantation success in the field compared to the 60–65% survival of plantlets recorded in the
experiments of previous workers. The plantlets derived through in vitro propagation mimic the growth and morphological characteristics of the donor plants. 相似文献
2.
Chandana Basu Mallick Florin Mircea Iliescu M?rt M?ls Sarah Hill Rakesh Tamang Gyaneshwer Chaubey Rie Goto Simon Y. W. Ho Irene Gallego Romero Federica Crivellaro Georgi Hudjashov Niraj Rai Mait Metspalu C. G. Nicholas Mascie-Taylor Ramasamy Pitchappan Lalji Singh Marta Mirazon-Lahr Kumarasamy Thangaraj Richard Villems Toomas Kivisild 《PLoS genetics》2013,9(11)
Skin pigmentation is one of the most variable phenotypic traits in humans. A non-synonymous substitution (rs1426654) in the third exon of SLC24A5 accounts for lighter skin in Europeans but not in East Asians. A previous genome-wide association study carried out in a heterogeneous sample of UK immigrants of South Asian descent suggested that this gene also contributes significantly to skin pigmentation variation among South Asians. In the present study, we have quantitatively assessed skin pigmentation for a largely homogeneous cohort of 1228 individuals from the Southern region of the Indian subcontinent. Our data confirm significant association of rs1426654 SNP with skin pigmentation, explaining about 27% of total phenotypic variation in the cohort studied. Our extensive survey of the polymorphism in 1573 individuals from 54 ethnic populations across the Indian subcontinent reveals wide presence of the derived-A allele, although the frequencies vary substantially among populations. We also show that the geospatial pattern of this allele is complex, but most importantly, reflects strong influence of language, geography and demographic history of the populations. Sequencing 11.74 kb of SLC24A5 in 95 individuals worldwide reveals that the rs1426654-A alleles in South Asian and West Eurasian populations are monophyletic and occur on the background of a common haplotype that is characterized by low genetic diversity. We date the coalescence of the light skin associated allele at 22–28 KYA. Both our sequence and genome-wide genotype data confirm that this gene has been a target for positive selection among Europeans. However, the latter also shows additional evidence of selection in populations of the Middle East, Central Asia, Pakistan and North India but not in South India. 相似文献
3.
4.
Aditya Nath Jha Vipin Kumar Singh Namrata Kumari Ashish Singh Justin Antony Hoang van Tong Sakshi Singh Sudhanshu S. Pati Pradeep K. Patra Rajender Singh Nguyen L. Toan Le H. Song Amal Assaf Iara J. T. Messias–Reason Thirumalaisamy P. Velavan Lalji Singh Kumarasamy Thangaraj 《PloS one》2012,7(10)
Background
Interleukin 4 (IL-4) is an anti-inflammatory cytokine, which regulates balance between TH1 and TH2 immune response, immunoglobulin class switching and humoral immunity. Polymorphisms in this gene have been reported to affect the risk of infectious and autoimmune diseases.Methods
We have analyzed three regulatory IL-4 polymorphisms; -590C>T, -34C>T and 70 bp intron-3 VNTR, in 4216 individuals; including: (1) 430 ethnically matched case-control groups (173 severe malaria, 101 mild malaria and 156 asymptomatic); (2) 3452 individuals from 76 linguistically and geographically distinct endogamous populations of India, and (3) 334 individuals with different ancestry from outside India (84 Brazilian, 104 Syrian, and 146 Vietnamese).Results
The -590T, -34T and intron-3 VNTR R2 alleles were found to be associated with reduced malaria risk (P<0.001 for -590C>T and -34C>T, and P = 0.003 for VNTR). These three alleles were in strong LD (r2>0.75) and the TTR2 (-590T, -34T and intron-3 VNTR R2) haplotype appeared to be a susceptibility factor for malaria (P = 0.009, OR = 0.552, 95% CI = 0.356 –0.854). Allele and genotype frequencies differ significantly between caste, nomadic, tribe and ancestral tribal populations (ATP). The distribution of protective haplotype TTR2 was found to be significant (χ2 3 = 182.95, p-value <0.001), which is highest in ATP (40.5%); intermediate in tribes (33%); and lowest in caste (17.8%) and nomadic (21.6%).Conclusions
Our study suggests that the IL-4 polymorphisms regulate host susceptibility to malaria and disease progression. TTR2 haplotype, which gives protection against malaria, is high among ATPs. Since they inhabited in isolation and mainly practice hunter-gatherer lifestyles and exposed to various parasites, IL-4 TTR2 haplotype might be under positive selection. 相似文献5.
Annadurai T Vigneshwari S Thirukumaran R Thomas PA Geraldine P 《Journal of physiology and biochemistry》2011,67(4):519-530
Acetyl-l-carnitine (ALCAR) has been shown to prevent experimental selenite cataractogenesis, a manifestation of oxidative stress,
but little is known about its potential in other settings of oxidative stress. The present study was based on the hypothesis
that ALCAR prevents carbon tetrachloride (CCl4)-induced oxidative stress in vital tissues. Male albino Wistar rats were divided into three groups, each of six rats. Group
I (control) rats received only vehicle (1 ml/kg b.w.) for 4 days; Group II (CCl4-exposed, untreated) rats received CCl4 (2 ml/kg b.w.) on the second and third days and vehicle on the first and fourth days; Group III (CCl4-exposed, ALCAR-treated) rats received ALCAR (200 mg/kg b.w.) for 4 days and CCl4 on the second and third days. All administrations were made intraperitoneally. After the experimental period, significantly
(P < 0.05) elevated mean serum levels of aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase
were observed in Group II rats when compared to Group I and Group III rats. The mean levels of vitamin C, vitamin E, and reduced
glutathione and the mean activities of superoxide dismutase, catalase, and glutathione peroxidase were significantly (P < 0.05) lower in samples of hemolysate and of liver, kidney, and brain tissues of Group II rats than those in Group I and
Group III rats. The mean level of lipid peroxidation was significantly (P < 0.05) higher in Group II rats than that in Group I and Group III rats. Moreover, the CCl4-induced upregulation of inducible nitric oxide synthase expression was prevented by ALCAR in the liver and brain tissues.
These results suggest that ALCAR is able to prevent the CCl4-induced oxidative stress. 相似文献
6.
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
7.
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
8.
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
9.
Mahesh R Devadoss T Pandey DK Bhatt S 《Bioorganic & medicinal chemistry letters》2011,21(4):1253-1256
A novel series of 3-ethoxyquinoxalin-2-carboxamides were designed as per the pharmacophoric requirements of 5-HT3 receptor antagonist using ligand-based approach. The desired carboxamides were synthesized from the key intermediate, 3-ethoxyquinoxalin-2-carboxylic acid by coupling with appropriate amines in the presence of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC·HCl) and 1-hydroxybenzotriazole (HOBt). The 5-HT3 receptor antagonism was evaluated in longitudinal muscle myenteric plexus preparation from guinea pig ileum against 5-HT3 agonist, 2-methy-5-HT, which was expressed in the form of pA2 values. Compound 6h (3-ethoxyquinoxalin-2-yl)(4-methylpiperazin-1-yl)methanone was found to be the most active compound, which expressed a pA2 value of 7.7. In forced swim test, the compounds with higher pA2 value exhibited good anti-depressant-like activity and compounds with lower pA2 value failed to show activity as compared to the vehicle-treated group. 相似文献
10.
The present study has been designed to investigate the effect of benfotiamine, a thiamine derivative, in sodium arsenite-induced
vascular endothelial dysfunction (VED) in rats. Sodium arsenite (1.5 mg−1 kg−1 day−1 i.p., 2 weeks) was administered in rats to produce VED. The development of VED was assessed by employing isolated aortic
ring preparation and estimating the serum and aortic concentrations of nitrite/nitrate. Further, the integrity of vascular
endothelium in thoracic aorta was assessed by scanning electron microscopy. Moreover, the oxidative stress was assessed by
estimating serum thiobarbituric acid reactive substances (TBARS) and aortic superoxide anion generation. The administration
of sodium arsenite markedly produced VED by attenuating acetylcholine-induced endothelium-dependent relaxation, decreasing
serum and aortic concentrations of nitrite/nitrate, and impairing the integrity of vascular endothelium. Further, sodium arsenite
produced oxidative stress by increasing serum TBARS and aortic superoxide generation. The treatment with benfotiamine (25,
50, and 100 mg−1 kg−1 day−1 p.o.) or atorvastatin (30 mg−1 kg−1 day−1 p.o., a standard agent) prevented sodium arsenite-induced VED and oxidative stress. However, the beneficial effects of benfotiamine
in preventing the sodium arsenite-induced VED were attenuated by co-administration with N-omega-nitro-l-arginine methyl ester (L-NAME) (25 mg−1 kg−1 day−1, i.p.), an inhibitor of NOS. Thus, it may be concluded that benfotiamine reduces oxidative stress and activates endothelial
nitric oxide synthase to enhance the generation and bioavailability of NO and subsequently improves the integrity of vascular
endothelium to prevent sodium arsenite-induced experimental VED. 相似文献