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排序方式: 共有284条查询结果,搜索用时 31 毫秒
111.
112.
Huda A. Eltahir Ameera A. M. Adam Zeinab A. Yahia Noon F. Ali Dalia M. Mursi Ashraaf M. Higazi Nahid A. Eid Ahmed M. Elhassan Hiba S. Mohammed Muntaser E. Ibrahim 《Molecular biology reports》2012,39(12):10833-10836
The aim of this report is to determine frequencies and associations of p53 codon 72 arg/pro polymorphism with different types of cancer in Sudan. p53 codon72 arg/pro polymorphism distribution and allele frequencies in 264 samples of different types of cancers were investigated using PCR. The results were compared to 235 normal controls. The results indicated significant differences in frequency and genotype association between different types of cancers. Breast carcinoma patients most prominently showed excess of homozygous arg genotype as compared to controls with an Odd ratio (OR) of 19.44, 95?%CI: 6.6–78.3, P?<?0.0001. Less prominently cervical cancer showed genotype effect of 2.4 OR, 95?%CI: 1.12–5.33, P?=?0.015, while esophageal cancer had an OR of 0.57, 95?%CI: 0.23–1.42, P?=?0.1. In Burkitt’s lymphoma, however, in contrast the homozygous arg accounted for only 6.9?%, (OR 0.18, 95?%CI: 0.02–0.89, P?=?0.018). We concluded that p53 arg/pro polymorphism has different pattern of frequency in different types of cancer among Sudanese patients, indicating perhaps different etiology and biology of these tumours. 相似文献
113.
David M. Katz Joanne E. Berger-Sweeney James H. Eubanks Monica J. Justice Jeffrey L. Neul Lucas Pozzo-Miller Mary E. Blue Diana Christian Jacqueline N. Crawley Maurizio Giustetto Jacky Guy C. James Howell Miriam Kron Sacha B. Nelson Rodney C. Samaco Laura R. Schaevitz Coryse St. Hillaire-Clarke Juan L. Young Huda Y. Zoghbi Laura A. Mamounas 《Disease models & mechanisms》2012,5(6):733-745
In September of 2011, the National Institute of Neurological Disorders and Stroke (NINDS), the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), the International Rett Syndrome Foundation (IRSF) and the Rett Syndrome Research Trust (RSRT) convened a workshop involving a broad cross-section of basic scientists, clinicians and representatives from the National Institutes of Health (NIH), the US Food and Drug Administration (FDA), the pharmaceutical industry and private foundations to assess the state of the art in animal studies of Rett syndrome (RTT). The aim of the workshop was to identify crucial knowledge gaps and to suggest scientific priorities and best practices for the use of animal models in preclinical evaluation of potential new RTT therapeutics. This review summarizes outcomes from the workshop and extensive follow-up discussions among participants, and includes: (1) a comprehensive summary of the physiological and behavioral phenotypes of RTT mouse models to date, and areas in which further phenotypic analyses are required to enhance the utility of these models for translational studies; (2) discussion of the impact of genetic differences among mouse models, and methodological differences among laboratories, on the expression and analysis, respectively, of phenotypic traits; and (3) definitions of the standards that the community of RTT researchers can implement for rigorous preclinical study design and transparent reporting to ensure that decisions to initiate costly clinical trials are grounded in reliable preclinical data. 相似文献
114.
A protein-protein interaction network for human inherited ataxias and disorders of Purkinje cell degeneration 总被引:34,自引:0,他引:34
Lim J Hao T Shaw C Patel AJ Szabó G Rual JF Fisk CJ Li N Smolyar A Hill DE Barabási AL Vidal M Zoghbi HY 《Cell》2006,125(4):801-814
Many human inherited neurodegenerative disorders are characterized by loss of balance due to cerebellar Purkinje cell (PC) degeneration. Although the disease-causing mutations have been identified for a number of these disorders, the normal functions of the proteins involved remain, in many cases, unknown. To gain insight into the function of proteins involved in PC degeneration, we developed an interaction network for 54 proteins involved in 23 inherited ataxias and expanded the network by incorporating literature-curated and evolutionarily conserved interactions. We identified 770 mostly novel protein-protein interactions using a stringent yeast two-hybrid screen; of 75 pairs tested, 83% of the interactions were verified in mammalian cells. Many ataxia-causing proteins share interacting partners, a subset of which have been found to modify neurodegeneration in animal models. This interactome thus provides a tool for understanding pathogenic mechanisms common for this class of neurodegenerative disorders and for identifying candidate genes for inherited ataxias. 相似文献
115.
116.
Al-Saleh E Nandakumaran M Al-Harmi J Sadan T Al-Enezi H 《Biological trace element research》2006,113(2):113-123
Obesity is well known to be a contributory risk factor for several disease states, including diabetes mellitus. Further, obese
women are more prone to have babies born with congenital abnormalities. Paucity of data on maternal-fetal disposition of essential
trace elements in obese pregnancies prompted us to undertake this study. Maternal venous and umbilical arterial and venous
samples were collected from obese patients (body mass index >30) and control pregnant women (body mass index <25) at time
of spontaneous delivery or cesarean sections and concentrations of essential trace elements such as Cu, Fe, Mo, Se, and Zn
determined in various samples by atomic absorption spectrophotometry. Activities of antioxidant enzymes, superoxide dismutase,
glutathione peroxidase, and total antioxidant activity in maternal and umbilical blood were assessed using appropriate reagent
kits. Maternal-fetal disposition and exchange parameters of elements studied were assessed using established critieria. Concentrations
of Cu, Fe, Mo, Se, and Zn in the serum of control pregnant women at time of delivery averaged 2232.6, 2398.1, 10.9, 108.9,
and 661.9 μg/L, respectively, whereas in the obese group, the values of the above elements averaged 2150.3, 2446.8, 12.6,
96.8, and 838.9 μg/L, respectively. Umbilical vein/maternal vein ratios of Cu, Fe, Mo, Se, and Zn in the control group averaged
0.29, 1.93, 1.06, 0.76, and 1.12, respectively, whereas in the obese group, their fetal-maternal ratios averaged 0.32, 2.23,
1.06, 0.78, and 1.53, respectively. The Cu:Zn ratio in the maternal vein of the obese group (3.60±0.20) was significantly
lower (Student's t-test; p<0.05) than that of the controls (2.50±0.19); however, Cu:Fe ratio (1.04±0.08 vs 1.02±0.09) was not significantly different
(Student's t-test; p>0.05) in the two groups. Varying differences were noted in the case of antioxidant enzyme activities between the control
and study groups. We conclude that obesity is associated with alterations in maternal-fetal disposition of some essential
trace elements and antioxidant enzyme status and that these alterations could pose a potential health risk for the mother
as well as the fetus. 相似文献
117.
Tawfik HE Cena J Schulz R Kaufman S 《American journal of physiology. Heart and circulatory physiology》2008,295(4):H1736-H1742
Multiparity is associated with increased risk of cardiovascular disease. We tested whether multiparity induces oxidative stress in rat vascular tissue. Coronary arteries and thoracic aorta were isolated from multiparous and age-matched virgin rats. Relaxation to ACh and sodium nitroprusside (SNP) was measured by wire myography. We also tested the effect of the superoxide dismutase mimetic MnTE2PyP (30 microM), the NADPH oxidase inhibitor apocynin (10 microM), and the peroxynitrite scavenger FeTPPs (10 microM) on ACh-mediated relaxation in coronary arteries. Vascular superoxide anion was measured using the luminol derivative L-012 and nitric oxide (NO) generation by the Griess reaction. Multiparity reduced maximal response and sensitivity to ACh in coronary arteries [maximal relaxation (E(max)): multiparous 49+/-3% vs. virgins 95%+/-3%; EC(50): multiparous 135+/-1 nM vs. virgins 60+/-1 nM], and in aortic rings (E(max): multiparous 38+/-3% vs. virgins 79+/-4%; EC(50): multiparous 160+/-2 nM vs. virgins 90+/-3 nM). Coronary arteries from the two groups relaxed similarly to SNP. Superoxide anions formation was significantly higher in both coronary arteries (2.8-fold increase) and aorta (4.1-fold increase) from multiparous rats compared with virgins. In multiparous rats, incubation with MnTE2PyP, apocynin, and FeTPPs improved maximal relaxation to ACh (MnTE2PyP: 74+/-5%; vehicle: 41+/-5%; apocynin: 73+/-3% vs. vehicle: 41+/-3%; FeTPPs: 72+/-3% vs. vehicle: 46+/-3%) and increased sensitivity (EC(50): MnTE2PyP: 61+/-0.5 nM vs. vehicle: 91+/-1 nM; apocynin: 45+/-3 nM vs. vehicle: 91+/-6 nM; FeTPP: 131 +/- 2 nM vs. vehicle: 185+/-1 nM). Multiparity also reduced total nitrate/nitrite levels (multiparous: 2.5+/-2 micromol/mg protein vs. virgins: 7+/-1 micromol/mg protein) and endothelial nitric oxide synthase protein levels (multiparous: 0.53+/-0.1 protein/actin vs. virgins: 1.0+/-0.14 protein/actin). These data suggest that multiparity induces endothelial dysfunction through decreased NO bioavailability and increased reactive oxygen species formation. 相似文献
118.
We investigated the relationship between habit, population size, floral traits and natural fruit set levels of 23 tropical
orchid species of south-east Bangladesh. We showed that epiphytic orchids had lower fruit set levels than terrestrial species
and that habit explained much of the variation in floral traits among the orchids. We compared our results with data from
76 other species occurring in the study area and hypothesize that a suite of floral and population characteristics present
in tropical orchids combine in epiphytes to reduce their reproductive success. Characteristics which, in addition to their
habit, are associated with low reproductive success are small population size, small inflorescences, non-sectile pollinia
and self-incompatibility. Several of these characteristics were phylogenetically conserved and we predict that epiphytes might
therefore generally have lower fruit set levels than recorded in terrestrial species. Nectar rewards are uncommon in tropical
orchids and nectarless species have displays of larger flowers, which may represent an adaptation to increase pollinator attraction,
although other rewards such as oils, waxes and pseudo pollen may replace nectar. We suggest that, like many temperate orchids,
a high proportion of tropical orchids may lack floral rewards and be pollinated by deceit. 相似文献
119.
Excel Que Kristen L James Alisha R Coffey Tangi L Smallwood Jody Albright M Nazmul Huda Daniel Pomp Praveen Sethupathy Brian J Bennett 《Genetics》2021,218(3)
Genetic approaches in model organisms have consistently demonstrated that molecular traits such as gene expression are under genetic regulation, similar to clinical traits. The resulting expression quantitative trait loci (eQTL) have revolutionized our understanding of genetic regulation and identified numerous candidate genes for clinically relevant traits. More recently, these analyses have been extended to other molecular traits such as protein abundance, metabolite levels, and miRNA expression. Here, we performed global hepatic eQTL and microRNA expression quantitative trait loci (mirQTL) analysis in a population of Diversity Outbred mice fed two different diets. We identified several key features of eQTL and mirQTL, namely differences in the mode of genetic regulation (cis or trans) between mRNA and miRNA. Approximately 50% of mirQTL are regulated by a trans-acting factor, compared to ∼25% of eQTL. We note differences in the heritability of mRNA and miRNA expression and variance explained by each eQTL or mirQTL. In general, cis-acting variants affecting mRNA or miRNA expression explain more phenotypic variance than trans-acting variants. Finally, we investigated the effect of diet on the genetic architecture of eQTL and mirQTL, highlighting the critical effects of environment on both eQTL and mirQTL. Overall, these data underscore the complex genetic regulation of two well-characterized RNA classes (mRNA and miRNA) that have critical roles in the regulation of clinical traits and disease susceptibility 相似文献
120.
Ruaa Ali Muhammed Ali Jamal Mohammed Ridha Alshara Nabil Salim Saaid Tuwaij Huda Jameel Baker Al-khilkhali 《Reports of Biochemistry & Molecular Biology》2022,11(1):166
Background:Escherichia coli (E. coli) remains one of the leading agents of urinary tract infection (UTIs), it has become resistant to many drugs. Current work aimed to evaluate some chemical substances as antibacterial agents and molecular study of virulence factors associated with UTIs.Methods:This work involved 133 urine specimens obtained from females’ patients suffering from UTIs, Methods of well diffusion and disk diffusion were achieved to assay the effect of some chemical substances and antibiogram profiles toward Sulfamethoxazole-trimethoprim (SXT)-resistant E. coli respectively. Virulence genes were done based on the technique of Polymerase Chain Reaction (PCR).Results:The results recorded 49/133 (36.84%) E. coli among women suffering UTIs, 28/49 (57.14%) were resistant to SXT drug. imipenem, meropenem, and nitrofurantoin were recorded more effectively. Chemicals substances at the concentration 0.3 (g/ml) recorded percentages of inhibition, reaching 9.143±1.442, 15.36±0.5914, and 21.82±0.8699 for NaHCO3, Ch4c, and Viroxide Super™ respectively. PCR demonstrated that 28/28 (100%) of SXT-resistant E. coli isolates were harbored Sul-2, FeoB and PapC genes, while 14/28 (50%), 15/28 (53.57%), 19/28 (67.85%) and 26/28 (92.85%) in U250 (pet), FumC, Sul-1 and IutA genes, respectively. Sul-3 gene was not observed.Conclusion:Observed a high percentage of E. coli that were resistant to SXT drug, and having several virulence genes, poses a real threat, it requires a real pause to create substitutions to limit the spreading of this threat.Key Words: Chemical substance, PCR, SXT-resistant E. coli, UTIs 相似文献