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921.
Iwata M Kawahara K Kawabata H Ito T Mera K Biswas KK Tancharoen S Higashi Y Kikuchi K Hashiguchi T Kanekura T Maruyama I 《Biochemical and biophysical research communications》2008,377(2):642-647
Thrombomodulin (TM) is an endothelial cell surface anticoagulant glycoprotein that performs antimetastatic, angiogenic, adhesive, and anti-inflammatory functions in various tissues. It is also expressed in epidermal keratinocytes. We found that a physiological dose (10 mJ/cm2) of mid-wavelength ultraviolet irradiation (UVB) significantly induced TM expression via the p38mitogen-activated protein kinase (MAPK)/cyclic AMP response element (CRE) signaling pathway in the epidermal keratinocyte cell line HaCaT; this shows that TM regulates the survival of HaCaT cells. SB203580, a p38MAPK inhibitor, significantly decreased TM expression and the viability of cells exposed to UVB. Furthermore, overexpression of TM markedly increased cell viability, and it was abrogated by TM small interfering RNA (siRNA), suggesting that TM may play an important role in exerting cytoprotective effect on epidermal keratinocytes against low-dose UVB. 相似文献
922.
Markan S Kohli HS Sud K Ahuja M Ahluwalia TS Sakhuja V Khullar M 《Molecular and cellular biochemistry》2008,311(1-2):105-110
Objective To evaluate the status of oxidative stress in patients with different primary glomerular diseases (PGD) which have differential
predisposition to renal failure. Methods Seventy-three patients with PGD and 50 controls were enrolled in the study. They were sub-grouped into non-proliferative
glomerulonephritis (NPGN) and proliferative glomerulonephritis (PGN). Levels of serum malondialdehyde (MDA), reactive nitrogen
intermediates (RNI), plasma total homocysteine (tHcy), urine 8-isoprostane (8-IP), RBC thiols, glutathione-S-transferase (GST)
and serum superoxide dismutase (SOD) were measured spectrophotometrically. Results PGD patients showed a significant increase in MDA, RNI, tHcy, 8-IP levels (P < 0.05) and decreased SOD, total thiols and protein bound thiol levels as compared to controls (P < 0.05). Significantly higher levels of tHcy, MDA and 8-IP (P < 0.05) and lower SOD enzyme activity (P < 0.05) were observed in PGN group as compared to NPGN and control groups. These changes remained significant even after adjustment
was made for creatinine. Conclusions Oxidative stress in PGN is significantly higher than NPGN, indicating higher oxidative stress in these patients, independent
of degree of renal dysfunction. 相似文献
923.
Kamal MA Klein P Luo W Li Y Holloway HW Tweedie D Greig NH 《Neurochemical research》2008,33(5):745-753
Cholinergic loss is the single most replicated neurotransmitter deficiency in Alzheimer’s disease (AD) and has led to the
use of acetylcholinesterase inhibitors (AChE-Is) and unselective cholinesterase inhibitors (ChE-Is) as the mainstay of treatment.
AChE-Is and ChE-Is, however, induce dose-limiting adverse effects. Recent studies indicate that selective butyrylcholinesterase
inhibitors (BuChE-Is) elevate acetylcholine (ACh) in brain, augment long-term potentiation, and improve cognitive performance
in rodents without the classic adverse actions of AChE-Is and ChE-Is. BuChE-Is thereby represent a new strategy to ameliorate
AD, particularly since AChE activity is depleted in AD brain, in line with ACh levels, whereas BuChE activity is elevated.
Our studies have focused on the design and development of cymserine analogues to induce selective time-dependent brain BuChE
inhibition, and on the application of innovative and quantitative enzyme kinetic analyses to aid selection of drug candidates.
The quantitative interaction of the novel inhibitor, dihydrobenzodioxepine cymserine (DHBDC), with human BuChE was characterized.
DHBDC demonstrated potent concentration-dependent binding with BuChE. The IC50 and specific new kinetic constants, such as KT50, PPC, KT1/2 and RI, were determined at dual substrate concentrations of 0.10 and 0.60 mM butyrylthiocholine and reaction times, and are likely
attainable in humans. Other classical kinetic parameters such as Kia, Kma, Vma and Vmi were also determined. In synopsis, DHBDC proved to be a highly potent competitive inhibitor of human BuChE in comparison
to its structural analogue, cymserine, and represents an interesting drug candidate for AD.
Dedicated to Professor Moussa Youdim, Dept. Pharmacology, Technion, Haifa, Israel, in celebrating 45 years in scientific research
focused on drug discovery and 30 years at Technion. 相似文献
924.
Nisha Jain Kamal Dhawan Sarla P Malhotra Saleem Siddiqui Randhir Singh 《Acta Physiologiae Plantarum》2001,23(3):357-362
Changes in chemical composition and hydrolytic enzyme activities in guava fruits cv. Lucknow-49 have been reported at four
different stages of maturity, viz., mature green (MG), color turning (CT), ripe (R) and over ripe (OR). Chlorophyll content decreased, while carotenoid content
increased with advancement of ripening. Starch content decreased with concomitant increase in alcohol soluble sugars. The
cell wall constituents viz., cellulose, hemicellulose, and lignin decreased up to R stage, while the pectin content decreased throughout up to OR stage.
Among the cell wall hydrolyzing enzymes, polygalacturonase (PG) and cellulase exhibited progressive increase in activity throughout
ripening, while pectin methyl esterase (PME) activity increased up to CT stage and then decreased up to OR stage. The maximum
increase in the activities of cell wall hydrolysing enzymes was observed between MG and CT stages. The activities of starch
hydrolyzing enzymes, α-amylase and β-amylase decreased significantly with advancement of ripening. These changes in the activities
of hydrolyzing enzymes could be considered good indicators of ripening in guava. 相似文献
925.
Gulalai Jamal Yousafzai Naseem Rafiq Mustafa Kamal Wali Khan Ghazala Yasmeen Zubia Masood Tahir Usman Najma Ghani Mohsinullah Mohsin Habib Ul Hassan 《Saudi Journal of Biological Sciences》2021,28(10):5925-5930
The occurrence of intestinal parasites of Columba livia domestica has been on the increase, leading to high economic and production losses with more fatal cases. This study was designed to investigate the prevalence of cestodes in pigeons and determine the efficacy of Typha angustata extract and sulphadimidine against these cestodes in the domestic pigeon. A total of 30 pigeons were examined. 18 (60%) pigeons were found infected with only one type of cestode species (Raillietina spp.). The difference in prevalence between males and females was statistically significant (χ2 = 8.167, p = 0.004). The mean EPG count in group A (treated with T. angustata extract) before treatment and after treatment was 176 ± 4.33 and 155 ± 4.24, respectively. In group B (treated with sulphadimidine), the mean EPG calculated before treatment and after treatment was 184 ± 6.74 and 35 ± 3.53, respectively. The efficacy at day 28 of T. angustata and Sulphadimidine was 11.93% and 80.97%, respectively. It was concluded on the basis of the EPG and efficacy data that T. angustata extract had low efficacy against raillietiniasis, while as sulphadimidine, which is also used before to treat different intestinal parasites, had a good efficacy against raillietiniasis. Further studies are required to know the prevalence of other gastrointestinal parasites in pigeons and efficacy of different medicinal plants against such parasites. 相似文献
926.
Post-translational modifications to histone proteins regulate the packaging of genomic DNA into chromatin, gene activity and other functions of the genome. They are understood to play key roles in embryonic development and disease pathogenesis. Recent advances in technology have made it possible to analyze chromatin structure genome-wide in mammalian cells. Global patterns of histone modifications can be observed using a technique called ChIP-on-chip, which combines the specificity of chromatin immunoprecipitation with the unbiased, high-throughput capabilities of microarrays. The resulting maps provide insight into the functions of, and relationships between, different modifications. Here, we provide validated ChIP-on-chip methods for analyzing histone modification patterns at genome-scale in mammalian cells. 相似文献
927.
Daniela Trani Kamal Datta Kathryn Doiron Bhaskar Kallakury Albert J. Fornace Jr 《Radiation and environmental biophysics》2010,49(3):389-396
Carcinogenesis induced by space radiation is considered a major risk factor in manned interplanetary and other extended missions.
The models presently used to estimate the risk for cancer induction following deep space radiation exposure are based on data
from A-bomb survivor cohorts and do not account for important biological differences existing between high-linear energy transfer
(LET) and low-LET-induced DNA damage. High-energy and charge (HZE) radiation, the main component of galactic cosmic rays (GCR),
causes highly complex DNA damage compared to low-LET radiation, which may lead to increased frequency of chromosomal rearrangements,
and contribute to carcinogenic risk in astronauts. Gastrointestinal (GI) tumors are frequent in the United States, and colorectal
cancer (CRC) is the third most common cancer accounting for 10% of all cancer deaths. On the basis of the aforementioned epidemiological
observations and the frequency of spontaneous precancerous GI lesions in the general population, even a modest increase in
incidence by space radiation exposure could have a significant effect on health risk estimates for future manned space flights.
Ground-based research is necessary to reduce the uncertainties associated with projected cancer risk estimates and to gain
insights into molecular mechanisms involved in space-induced carcinogenesis. We investigated in vivo differential effects
of γ-rays and HZE ions on intestinal tumorigenesis using two different murine models, ApcMin/+ and Apc1638N/+. We showed that
γ- and/or HZE exposure significantly enhances development and progression of intestinal tumors in a mutant-line-specific manner,
and identified suitable models for in vivo studies of space radiation–induced intestinal tumorigenesis. 相似文献
928.
CC2D2A, encoding a coiled-coil and C2 domain protein, causes autosomal-recessive mental retardation with retinitis pigmentosa
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Noor A Windpassinger C Patel M Stachowiak B Mikhailov A Azam M Irfan M Siddiqui ZK Naeem F Paterson AD Lutfullah M Vincent JB Ayub M 《American journal of human genetics》2008,82(4):1011-1018
Autosomal-recessive inheritance is believed to be relatively common in mental retardation (MR), although only four genes for nonsyndromic autosomal-recessive mental retardation (ARMR) have been reported. In this study, we ascertained a consanguineous Pakistani family with ARMR in four living individuals from three branches of the family, plus an additional affected individual later identified as a phenocopy. Retinitis pigmentosa was present in affected individuals, but no other features suggestive of a syndromic form of MR were found. We used Affymetrix 500K microarrays to perform homozygosity mapping and identified a homozygous and haploidentical region of 11.2 Mb on chromosome 4p15.33-p15.2. Linkage analysis across this region produced a maximum two-point LOD score of 3.59. We sequenced genes within the critical region and identified a homozygous splice-site mutation segregating in the family, within a coiled-coil and C2 domain-containing gene, CC2D2A. This mutation leads to the skipping of exon 19, resulting in a frameshift and a truncated protein lacking the C2 domain. Conservation analysis for CC2D2A suggests a functional domain near the C terminus as well as the C2 domain. Preliminary functional studies of CC2D2A suggest a possible role in Ca(2+)-dependent signal transduction. Identifying the function of CC2D2A, and a possible common pathway with CC2D1A, in correct neuronal development and functioning may help identify possible therapeutic targets for MR. 相似文献
929.
Srivastava RK Krishna A 《Journal of experimental zoology. Part A, Ecological genetics and physiology》2008,309(2):94-110
The aim of this study was to determine the effect of changes in body mass, fat reserves and feeding activity on circulating levels of lipids, glucose, protein and metabolic hormones in a vespertilionid bat, Scotophilus heathi. Furthermore, the relationship between changes in metabolic factors and hormones with the unique reproductive features of female S. heathi was also examined. The results of this study showed annual variation in body mass, fat reserve and feeding activity, which correlated significantly with circulating levels of lipids, protein and metabolic hormones. Increased corticosterone level during September-October in S. heathi promotes increased feeding activity, which in turn induces hyperinsulinemia in S. heathi during November. Hyperinsulinemia together with low body temperature in November facilitates fat accumulation in bat. Coinciding with the period of fat accumulation raises serum leptin level, which has been demonstrated to suppress ovarian activities thus causing delayed ovulation in S. heathi. Circulating levels of lipids were high during winter dormancy, which may provide energy to stored sperms. The study thus suggests that the unique reproductive features of female vespertilionid bat are strongly linked to fat deposition. J. Exp. Zool. 309A:94-110, 2008. (c) 2008 Wiley-Liss, Inc. 相似文献
930.
Itrat A Khan A Javaid S Kamal M Khan H Javed S Kalia S Khan AH Sethi MI Jehan I 《PloS one》2008,3(7):e2620