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91.
毛蕊铁线莲的组织培养与植株再生 总被引:1,自引:0,他引:1
1植物名称毛蕊铁线莲(Clematis lasiandra Maxim.),别名小木通、丝瓜花。2材料类别带芽茎段、节间和叶片。3培养条件诱导培养基:(1)MS+6-BA0.5mg.L-1(单位下同)+NAA0.05+3%蔗糖;(2)MS+6-BA0.5+NAA0.1+2,4-D0.1+3%蔗糖;(3)MS+6-BA2.O+NAA0.1+3%蔗糖。增殖分化培养基:(4)MS+6-BA1.0+NAA0.1+3%蔗糖;(5)MS+6.BA2.0+NAA0.1+2,4-D0.01+3%蔗糖;(6)MS+6.BA2.0+NAA0.05+3%蔗糖。生根培养基:(7)1/4MS+NAA0.5+0.1%活性炭+15%蔗糖。所有培养基均附加0.6%琼脂粉,pH5.8-6.0,培养温度为(25±2)℃,光照强度为3040gm01.m-2.S-1,光照时间为14h.d-1。 相似文献
92.
Xing Fan Li-Na Sha Rui-Wu Yang Hai-Qin Zhang Hou-Yang Kang Cun-Bang Ding Li Zhang You-Liang Zheng Yong-Hong Zhou 《BMC evolutionary biology》2009,9(1):247-15
Background
Single- and low- copy genes are less likely subject to concerted evolution, thus making themselves ideal tools for studying the origin and evolution of polyploid taxa. Leymus is a polyploid genus with a diverse array of morphology, ecology and distribution in Triticeae. The genomic constitution of Leymus was assigned as NsXm, where Ns was presumed to be originated from Psathyrostachys, while Xm represented a genome of unknown origin. In addition, little is known about the evolutionary history of Leymus. Here, we investigate the phylogenetic relationship, genome donor, and evolutionary history of Leymus based on a single-copy nuclear Acc1 gene. 相似文献93.
Zongxiang Tang Shulan Fu Zhenglong Ren Yuting Zou 《Journal of molecular evolution》2009,69(3):217-228
Microsatellite evolution normally occurs in diploids. Until now, there has been a lack of direct experimental evidence for
microsatellite evolution following allopolyploidization. In the present study, F1 hybrids and newly synthesized allopolyploids were derived from Triticum aestivum Chinese Spring × Secale cereale Jinzhou-heimai. One hundred and sixty-three wheat simple sequence repeat (SSR) markers were used to investigate the variation
of wheat microsatellites after allopolyploidization and variation of the PCR products of 29 of the SSR markers was observed.
Of these 29 SSR markers, 15 were unable to produce products from amphiploids. The other 14 SSR markers did produce products
from parental wheat, F1 hybrids and amphiploids. However, the length of the products amplified from amphiploids was different from the length of
the products amplified from parental wheat and F1 hybrids. Sequencing indicated that the length variation of the 14 microsatellites stemmed mainly from variation in the number
of repeat units. The alteration of repeat units occurred in both perfect and compound repeats. In some compound SSR loci,
one motif was observed to expand whereas another to contract. Almost all the microsatellite evolution observed in this study
could be explained by the slipped-strand mispairing model. The results of this study seem to indicate that stress caused by
allopolyploidization might be one of the factors that induce microsatellite evolution. In addition, the findings of present
study provided an instance of how simple sequence repeats evolved after allopolyploidization. 相似文献
94.
Wei Qiao Zhongli Peng Zhisheng Wang Jing Wei Anguo Zhou 《Biological trace element research》2009,131(2):133-142
The aim of this study was to evaluate the impact of three different chromium forms as chromic chloride (CrCl), chromium picolinate
(CrPic), and a newly synthesized complex of chromium chelated with small peptides (CrSP) on glucose uptake and metabolism
in vitro. In cultured skeletal muscle cells, chromium augmented insulin-stimulated glucose uptake and metabolism as assessed
by a reduced glucose concentration of culture medium. At the molecular level, insulin significantly increased the mRNA levels
of insulin receptor (IR), glucose transporter 4 (GLUT4), glycogen synthase (GS), and uncoupling protein-3 (UCP3), and these
impacts can be enhanced by the addition of chromium, especially in the form of CrSP. Collectively, results of this study demonstrate
that chromium improves glucose uptake and metabolism through upregulating the mRNA levels of IR, GLUT4, GS, and UCP3 in skeletal
muscle cells, and CrSP has higher efficacy on glucose uptake and metabolism compared to the forms of CrCl and CrPic. 相似文献
95.
Xi Peng Yun Cui Wei Cui Junliang Deng Hengmin Cui 《Biological trace element research》2009,131(1):33-42
Selenium is an essential trace element possessing immune-stimulatory properties. The purpose of this 42-day study was to investigate
the effects of excess dietary sodium selenite on immune function by determining morphological changes and apoptosis of bursa
of Fabricius. Three hundred 1-day-old Avian broilers were fed on a basic diet (0.2 ppm selenium) or the same diet amended
to contain 1, 5, 10, and 15 ppm selenium supplied as sodium selenite (n = 60/group). Relative weight of bursa was significantly decreased in the 1, 5, 10, and 15 ppm groups at 28 days of age, when
compared with that of 0.2 ppm group. Pathological lesions were progressed with the dietary Se level increased. The gross lesions
of bursa involved obvious atrophy with decreased volume and pale color. Histopathologically, decreased number of lymphocytes
and loosely packed lymphocytes appeared in the medulla and cortex in the follicles. Ultrastructurally, mitochondria injury
and increased apoptotic cells with condensed nuclei were observed. In comparison to that of control group, excess Se (5, 10,
and 15 ppm) intake increased the percentage of Annexin V positive cells, as measured by flow cytometry. Terminal deoxynucleotidyl
transferase 2′-deoxyuridine 5′-triphosphate nick end-labeling assay showed that there were increased frequencies of apoptotic
cells in 10 and 15 ppm selenium groups. These data suggest that Se supplementation with sodium selenite should be carefully
evaluated as excess selenium (more than 5 ppm) intake could cause profound immunologic inhibition. 相似文献
96.
97.
Dongsheng Zhou Yong zhuo Lianqiang Che Yan Lin Zhengfeng Fang De Wu 《Molecular biology reports》2014,41(7):4733-4742
People on a diet to lose weight may be at risk of reproductive failure. To investigate the effects of nutrient restriction on reproductive function and the underlying mechanism, changes of reproductive traits, hormone secretions and gene expressions in hypothalamus–pituitary–gonadal axis were examined in postpubertal gilts at anestrus induced by nutrient restriction. Gilts having experienced two estrus cycles were fed a normal (CON, 2.86 kg/d) or nutrient restricted (NR, 1 kg/d) food regimens to expect anestrus. NR gilts experienced another three estrus cycles, but did not express estrus symptoms at the anticipated fourth estrus. Blood samples were collected at 5 days’ interval for consecutive three times for measurement of hormone concentrations at the 23th day of the fourth estrus cycle. Individual progesterone concentrations of NR gilts from three consecutive blood samples were below 1.0 ng/mL versus 2.0 ng/mL in CON gilts, which was considered anestrus. NR gilts had impaired development of reproductive tract characterized by absence of large follicles (diameter ≥ 6 mm), decreased number of corepus lutea and atrophy of uterus and ovary tissues. Circulating concentrations of IGF-I, kisspeptin, estradiol, progesterone and leptin were significantly lower in NR gilts than that in CON gilts. Nutrient restriction down-regulated gene expressions of kiss-1, G-protein coupled protein 54, gonadotropin-releasing hormone, estrogen receptor α, progesterone receptor, leptin receptor, follicle-stimulating hormone and luteinizing hormone and insulin-like growth factor I in hypothalamus–pituitary–gonadal axis of gilts. Collectively, nutrient restriction resulted in impairment of reproductive function and changes of hormone secretions and gene expressions in hypothalamus–pituitary–gonadal axis, which shed light on the underlying mechanism by which nutrient restriction influenced reproductive function. 相似文献
98.
99.
《Systematic and applied microbiology》2014,37(8):560-569
The taxonomic diversity of forty-two Rhizobium strains, isolated from nodules of faba bean grown in Egypt, was studied using 16S rRNA sequencing, multilocus sequence analyses (MLSA) of three chromosomal housekeeping loci and one nodulation gene (nodA). Based on the 16S rRNA gene sequences, most of the strains were related to Rhizobium leguminosarum, Rhizobium etli, and Rhizobium radiobacter (syn. Agrobacterium tumefaciens). A maximum likelihood (ML) tree built from the concatenated sequences of housekeeping proteins encoded by glnA, gyrB and recA, revealed the existence of three distinct genospecies (I, II and III) affiliated to the defined species within the genus Rhizobium/Agrobacterium. Seventeen strains in genospecies I could be classified as R. leguminosarum sv. viciae. Whereas, a single strain of genospecies II was linked to R. etli. Interestingly, twenty-four strains of genospecies III were identified as A. tumefaciens. Strains of R. etli and A. tumefaciens have been shown to harbor the nodA gene and formed effective symbioses with faba bean plants in Leonard jar assemblies. In the nodA tree, strains belonging to the putative genospecies were closely related to each other and were clustered tightly to R. leguminosarum sv. viciae, supporting the hypothesis that symbiotic and core genome of the species have different evolutionary histories and indicative of horizontal gene transfer among these rhizobia. 相似文献
100.
Prolonged and excessive glucocorticoids (GC) exposure resulted from Cushing''s syndrome or GC therapy develops central obesity. Moreover, mitochondria are crucial in adipose energy homeostasis. Thus, we tested the hypothesis that mitochondrial dysfunction may contribute to chronic GC exposure-induced epididymal adiposity in the present study. A total of thirty-six 5-week-old male C57BL/6J mice (∼20 g) were administrated with 100 µg/ml corticosterone (CORT) or vehicle through drinking water for 4 weeks. Chronic CORT exposure mildly decreased body weight without altering food and water intake in mice. The epididymal fat accumulation was increased, but adipocyte size was decreased by CORT. CORT also increased plasma CORT, insulin, leptin, and fibroblast growth factor 21 concentrations as measured by RIA or ELISA. Interestingly, CORT increased plasma levels of triacylglycerols and nonesterified fatty acids, and up-regulated the expression of both lipolytic and lipogenic genes as determined by real-time RT-PCR. Furthermore, CORT impaired mitochondrial biogenesis and oxidative function in epididymal WAT. The reactive oxygen species production was increased and the activities of anti-oxidative enzymes were reduced by CORT treatment as well. Taken together, these findings reveal that chronic CORT administration-induced epididymal adiposity is, at least in part, associated with mitochondrial dysfunction in mouse epididymal white adipose tissue. 相似文献