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141.
Investigations of humans with disorders of sex development (DSDs) resulted in the discovery of many of the now-known mammalian sex-determining genes, including SRY, RSPO1, SOX9, NR5A1, WT1, NR0B1, and WNT4. Here, the locus for an autosomal sex-determining gene was mapped via linkage analysis in two families with 46,XY DSD to the long arm of chromosome 5 with a combined, multipoint parametric LOD score of 6.21. A splice-acceptor mutation (c.634-8T>A) in MAP3K1 segregated with the phenotype in the first family and disrupted RNA splicing. Mutations were demonstrated in the second family (p.Gly616Arg) and in two of 11 sporadic cases (p.Leu189Pro, p.Leu189Arg)-18% prevalence in this cohort of sporadic cases. In cultured primary lymphoblastoid cells from family 1 and the two sporadic cases, these mutations altered the phosphorylation of the downstream targets, p38 and ERK1/2, and enhanced binding of RHOA to the MAP3K1 complex. Map3k1 within the syntenic region was expressed in the embryonic mouse gonad prior to, and after, sex determination. Thus, mutations in MAP3K1 that result in 46,XY DSD with partial or complete gonadal dysgenesis implicate this pathway in normal human sex determination.  相似文献   
142.
ABSTRACT: Amiri-Khorasani, M, MohammadKazemi, R, Sarafrazi, S, Riyahi-Malayeri, S, and Sotoodeh, V. Kinematics analyses related to stretch-shortening cycle during soccer instep kicking after different acute stretching. J Strength Cond Res 26(11): 3010-3017, 2012-The purpose of this study was to examine the effects of static and dynamic stretching within a preexercise warm-up on angular velocity of knee joint, deepest knee flexion (DKF), and duration of eccentric and concentric contractions, which are relative to the stretch-shortening cycle (SSC) during instep kicking in professional soccer players. The kicking motions of dominant legs were captured from 18 Olympic professional male soccer players (height: 180.38 ± 7.34 cm; weight: 69.77 ± 9.73 kg; age: 19.22 ± 1.83 years) using 4 digital video cameras at 50 Hz. There was a significant difference in the DKF after the dynamic stretching (-3.22 ± 3.10°) vs. static stretching (-0.18 ± 3.19°) relative to the no-stretching method with p < 0.001. Moreover, there was significant difference in eccentric duration after the dynamic stretching (0.006 ± 0.01 seconds) vs. static stretching (-0.003 ± 0.01 seconds) relative to the no-stretching method with p < 0.015. There was a significant difference in the concentric duration after the dynamic stretching (-0.007 ± 0.01 seconds) vs. static stretching (0.002 ± 0.01 seconds) relative to the no-stretching method with p < 0.001. There was also a significant difference in knee angular velocity after the dynamic stretching (4.08 ± 3.81 rad·s) vs. static stretching (-5.34 ± 4.40 rad·s) relative to the no-stretching method with p < 0.001. We concluded that dynamic stretching during warm-ups, as compared with static stretching, is probably the most effective way as preparation for the kinematics characteristics of soccer instep kick, which are relative to the SSC.  相似文献   
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Since time immemorial, human beings have sought natural medications for treatment of various diseases. Weighty evidence demonstrates the use of chemical methodologies for sensitive evaluation of cytotoxic potentials of herbal agents. However, due to the ubiquitous use of cytotoxicity methods, there is a need for providing updated guidance for the design and development of in vitro assessment. The aim of this review is to provide practical guidance on common cell-based assays for suitable assessment of cytotoxicity potential of herbal medicines and discussing their advantages and disadvantages Relevant articles in authentic databases, including PubMed, Web of Science, Science Direct, Scopus, Google Scholar and SID, from 1950 to 2022 were collected according to selection criteria of in vitro cytotoxicity assays and protocols. In addition, the link between cytotoxicity assay selection and different factors such as the drug solvent, concentration and exposure duration were discussed.  相似文献   
145.
The lack of a Near Eastern genetic signature in modern European porcine breeds indicates that, although domestic pigs from the Fertile Crescent entered Europe during the Neolithic, they were completely replaced by their European counterparts in a short window of time. Whilst the absence of such genetic signature has been convincingly demonstrated at the mitochondrial level, variation at the autosomal genomes of European and Near Eastern Sus scrofa has not been compared yet. Herewith, we have explored the genetic relationships among 43 wild boar from Europe (N = 21), Near East (N = 19) and Korea (N = 3), and 40 Iberian (N = 16), Canarian (N = 4) and Mangalitza (N = 20) pigs by using a high throughput SNP genotyping platform. After data filtering, 37,167 autosomal SNPs were used to perform population genetics analyses. A multidimensional scaling plot based on genome-wide identity-by-state pairwise distances inferred with PLINK showed that Near Eastern and European wild boar populations are genetically differentiated. Maximum likelihood trees built with TreeMix supported this conclusion i.e. an early population split between Near Eastern and European Sus scrofa was observed. Moreover, analysis of the data with Structure evidenced that the sampled Iberian, Canarian and Mangalitza pigs did not carry any autosomal signature compatible with a Near Eastern ancestry, a finding that agrees well with previous mitochondrial studies.  相似文献   
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147.
Mycoplasma contamination is a deleterious event for cell culture laboratories. Plasmocin™ is used to prevent and eradicate mycoplasma infections from cell. In this study, 80 different mammalian cell lines from various sources; human, monkey, mice, hamster and rat were used to study and evaluate plasmocin™ efficiency and compare it to commonly used antibiotics such as BM-cyclin, ciprofloxacin and mycoplasma removal agent (MRA). It was shown that mycoplasma infections were eradicated by plasmocin™, BM-cyclin, ciprofloxacin and MRA in 65%, 66.25%, 20%, and 31.25%, respectively, of infected cell cultures. However, re-infection with mycoplasmas after the period of 4 months occurred in 10–80% of the studied cell lines. Cell cytotoxicity and culture death was observed in 25, 17.5 and 10% of the treated cells, for plasmocin™, BM-cyclin and MRA, respectively. In this study, Plasmocin™ showed strong ability to eradicate mollicutes from our cell lines with minimal percentage of regrowth. However, due to its high cell cytotoxicity it should be used with caution especially when dealing with expensive or hard-to-obtain cell lines. Amongst the antibiotics tested, BM-cyclin was shown to remove mycoplasma with the highest efficiency.  相似文献   
148.
Heterotrimeric G proteins are critical transducers of cellular signaling. Of the four families of G proteins, the physiological function of Gα13 is less well understood. Gα13 gene-deleted mice die at embryonic day ∼9.5. Here, we show that heterozygous Gα13+/− mice display defects in adult angiogenesis. Female Gα13+/− mice showed a higher number of immature follicles and a lower density of blood vessels in the mature corpus luteum compared with Gα13+/+ mice. Furthermore, implanted tumors grew slower in Gα13+/− host mice. These tumor tissues had many fewer blood vessels compared with those from Gα13+/+ host mice. Moreover, bone marrow-derived progenitor cells from Gα13+/+ mice rescued the failed growth of allografted tumors when reconstituted into irradiated Gα13+/− mice. Hence, Gα13 is haploinsufficient for adult angiogenesis in both the female reproductive system and tumor angiogenesis.A structurally diverse repertoire of ligands, from photons to large peptides, activates G protein-coupled receptors to elicit their physiological functions (1). In turn, ligand-bound G protein-coupled receptors function as guanine nucleotide exchange factors, catalyzing the exchange of GDP bound on the Gα subunit with GTP in the presence of Gβγ and causing the dissociation of the Gα subunit from the Gβγ dimer to form two functional units (Gα and Gβγ) (2). Both Gα and Gβγ subunits signal to various cellular pathways. Based on sequence and functional homologies, G proteins are grouped into four families: Gs, Gi, Gq, and G12 (3). Of these four subfamilies of G proteins, the physiological function of the G12 subfamily is less well understood. In this family, there are two members, G12 and G13. Gα12 knock-out mice appear normal (4). Gα13 knock-out mice display embryonic lethality (embryonic day ∼9.5) (5). Gα13−/− mouse embryos have defective vascular systems (5). Endothelial cell-specific deletion of Gα13 also results in vascular defect and embryonic lethality (6). The molecular basis that underlies the vascular defect observed in Gα13−/− mouse embryos has not been defined.Angiogenesis (formation of endothelium-lined blood vessels) is essential for organ growth in the embryo and for repair of wounded tissues in the adult (7, 8). An imbalance in angiogenesis contributes to the pathogenesis of numerous malignant, inflammatory, ischemic, infectious, and immune disorders and cancers (7, 8). Most angiogenesis events take place during embryonic development. In adult tissues, the majority of endothelial cells are quiescent, and angiogenesis occurs only rarely except in a few adult tissues (including ovary) that exhibit periodic and dynamic growth and regression (911). Under pathological conditions such as tumor growth, adult angiogenesis is induced. Tumor angiogenesis is the proliferation of a network of blood vessels that penetrates into cancerous growths (including implanted tumor tissues), supplying nutrients and oxygen and removing waste products. Solid tumors depend on angiogenesis for growth and metastasis in a hostile environment (12). Bone marrow is the origin of endothelial progenitor cells in the adult. Bone marrow-derived endothelial progenitor cells are mobilized into peripheral blood and recruited to the foci of pathophysiological neovascularization and re-endothelialization, thereby contributing to vascular regeneration (13). Vascular endothelial growth factor (VEGF),2 the most critical factor for angiogenesis, is an important factor for the mobilization of endothelial progenitor cells from bone marrow (7, 8). Bone marrow transplantation experiments have demonstrated the incorporation of bone marrow-derived endothelial progenitor cells into foci of pathological neovascularization such as growing tumors, healing wounds, ischemic skeletal and cardiac muscles, and cornea receiving micropocket surgery (1421).Here, we show that heterozygous Gα13+/− mice display defects in adult angiogenesis. We found that female Gα13+/− mice show a higher number of immature follicles and a lower density of blood vessels in the mature corpus luteum compared with Gα13+/+ mice. Furthermore, implanted tumors grew slower in Gα13+/− host mice. These tumor tissues had many fewer blood vessels compared with those from Gα13+/+ host mice. We also down-regulated Gα13 in endothelial cells by RNA interference and show that defective migration and tube formation in response to VEGF likely contribute to the impaired angiogenesis. Moreover, bone marrow-derived cells from Gα13+/+ mice rescued the failed growth of allografted tumors when reconstituted into irradiated Gα13+/− mice. Our results demonstrate that Gα13 is haploinsufficient for adult angiogenesis in both the female reproductive system and tumor angiogenesis. This role in adult angiogenesis provides a suitable system to further investigate the biochemical and physiological functions of Gα13. Moreover, Gα13 inhibition could be explored for anticancer drug development.  相似文献   
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Systematics of the genus Isatis (Brassicaceae) is difficult and controversial, and previous studies were based solely on morphological characters. Sequence variation of the internal transcribed spacer (ITS) regions and the 5.8S gene of nuclear ribosomal DNA (nrDNA) were analyzed using parsimony and Bayesian methods. Twenty-eight taxa of Isatis and related genera of the tribe Isatideae were sampled, including 20 Isatis species representing almost all major morphological lineages, all three species of Pachypterygium, two of nine species of Sameraria, and monospecific Boreava, Myagrum, and Tauscheria. Two well-supported clades were resolved in the ITS tree, and they demonstrate the artificiality of the present delimitation of the tribe. One clade includes I. emarginata, I. minima, I. trachycarpa, P. brevipes, P. multicaule, P. stocksii, and T. lasiocarpa. The second clade includes I. buschiana, the polymorphic I. cappadocica with five subspecies, I. gaubae, I. kotschyana, I. leuconeura, I. pachycarpa, I. takhtajanii, I. tinctoria, and S. armena. Pachypterygium is polyphyletic and, together with Boreava, Sameraria, and Tauscheria, all are nested within Isatis. This study is a continuation of our recent systematic survey based on seed-coat microsculpturing ( Moazzeni et al., 2007. Flora 202, 447–454) and reveals that fruit characters mapped onto the molecular tree show considerable convergence. The reliance on fruit characters alone in the delimitation of genera may well lead to erroneous phylogenetic results and thus to incorrect taxonomic conclusions.  相似文献   
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