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261.
BACKGROUND : Genetic and environmental factors likely influence susceptibility to nonsyndromic cryptorchidism, a common disease presenting at birth or in later childhood. We compared cases and controls to define differential risk factors for congenital versus acquired cryptorchidism. METHODS : We compared questionnaire and clinical data from cases of congenital cryptorchidism (n = 230), acquired cryptorchidism (n = 182) and hernia/hydrocele (n = 104) with a group of healthy male controls (n = 358). Potential predictor variables (p < 0.2 in univariable analysis) were included in stepwise multivariable logistic regression models. RESULTS : Temporary (odds ratio [OR], 0.5; 95% confidence interval [CI], 0.4–0.8) or exclusive (OR, 0.6; 95% CI, 0.4–0.9) breastfeeding was reduced and soy formula feeding increased (OR, 1.8; 95% CI, 1.2–2.9) in acquired but not congenital or hernia/hydrocele groups. The highest risk estimates were observed for primary soy formula feeding with limited or no breastfeeding (OR 2.5; 95% CI, 1.4–4.3; adjusted OR, 2.7; 95% CI, 1.4–5.4) in the acquired group. Primary feeding risk estimates were equivalent or strengthened when multivariable models were limited to age greater than 2 years, full‐term or not small for gestational age, or Caucasian subjects. Pregnancy complications and increased maternal exposure to cosmetic or household chemicals were not consistently associated with either form of cryptorchidism in these models. CONCLUSIONS : Our data support reduced breastfeeding and soy formula feeding as potential risk factors for acquired cryptorchidism. Although additional studies are needed, hormonally active components of breast milk and soy formula could influence the establishment of normal testis position in the first months of life, leading to apparent ascent of testes in childhood. Birth Defects Research (Part A), 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
262.
To isolate enantioselective α-hydroxyacid dehydrogenases (α-HADHs), a high-throughput screening method was established. 2,4-Dinitrophenylhydrazine solution forms a red-brown complex with ketoacid produced during the α-HADH-mediated oxidation of α-hydroxyacid. The complex can be easily quantified by spectrophotometric measurement at 458?nm. The enantioselectivity of α-HADH in each strain can be measured with this colorimetric method using (R)- and (S)-α-hydroxyacid concurrently as substrates to evaluate the apparent enantioselectivity (E app). The E app closely matches the value of true enantioselectivity (E true) determined by HPLC analysis. With this method, a total of 34 stains harboring enantioselective α-HADHs were selected from 526 potential α-HADH-producing microorganisms. Pseudomonas aeruginosa displayed the highest (S)-enantioselective α-HADH activity. This strain appears promising for potential application in industry to produce (R)-α-hydroxyacids. The method described herein represents a useful tool for the high-throughput isolation of enantioselective α-HADHs.  相似文献   
263.
L Yan  A Wang  L Chen  W Shang  M Li  Y Zhao 《Gene》2012,506(2):350-354
The present study investigated the expression of the apoptosis-related genes fas-associated via death domain (FADD) and Bcl-2 in the endometrium during the window of implantation in polycystic ovary syndrome (PCOS) patients. The aim was to explore the role of cell apoptosis in endometrial receptivity during this period. The subjects were divided into experimental and control group. The experimental group comprised 12 infertile women with PCOS, and the control group comprised 12 women who were infertile because of tubal pathological factors but had normal menstrual cycles. Endometria were collected by biopsy 7d after ovulation. Six samples from each group were randomly selected and subjected to gene chip analyses. The expression of endometrial FADD and Bcl-2 was determined by immunohistochemistry, and cell apoptosis was detected by the TUNEL method. Compared with the control group, 194 differentially expressed genes were found in the PCOS group, 102 of which were upregulated and 92 were downregulated. The differentially expressed genes were divided into 15 types according to function. Among the nine genes related to cell apoptosis, five (including Bcl-2) were upregulated and four were downregulated (including FADD). Bcl-2 expression during the window of implantation in the PCOS group increased compared with the control group, showing a significant difference (P<0.05). FADD expression in the PCOS group notably decreased compared with that in the control group, which also showed a significant difference (P<0.05). Cell apoptosis analysis showed a significant difference between the average apoptotic indices in the PCOS and control groups (P<0.05). Significant differences were observed between the endometrial gene expression in the PCOS and control groups. The decrease in cell apoptosis during the window of implantation in PCOS patients may be one of the causes of the reduced endometrial receptivity.  相似文献   
264.

Background

Nasopharyngeal carcinoma (NPC) is known for its high metastatic potential and locoregional recurrence, although the molecular alterations that are driving NPC metastasis remain unclear at this time. This study aimed to examine the expression of fibulin-5 in NPC, correlate the results with clinicopathological variables and survival, and to investigate the role of fibulin-5 in human NPC cell lines.

Material and Methods

Standard semi-quantitative-RT-PCR, quantitative-RT-PCR, immunoblotting, and immunohistochemistry were used to investigate the mRNA and protein expression profiles of fibulin-5 in normal and NPC tissues. Immunohistochemistry of fibulin-5 was correlated with clinicopathological characteristics by univariate analyses. NPC cells overexpressing fibulin-5 or fibulin-5-siRNA cells were generated by stable transfection to characterize the molecular mechanisms of fibulin-5-elicited cell growth and metastasis.

Results

Our results demonstrated that fibulin-5 overexpression in NPC specimens and significantly correlated with advanced tumor metastasis indicating a poor 5-year overall survival. Fibulin-5 was mainly expressed in the nucleus in human NPC specimens and cell lines. Functionally, fibulin-5 overexpression yielded fast growth in NPC cells. In addition, fibulin-5 promotes cell metastasis in NPC cells through increased FLJ10540 and phosphor-AKT activity. In contrast, siRNA depletion of fibulin-5 suppressed FLJ10540 expression and phosphor-AKT activity. Suppression of either fibulin-5 or FLJ10540 can cause significant inhibition with regards to cell motility in NPC cells. Finally, immunohistochemical analysis of human aggressive NPC specimens showed a significant and positive correlation between fibulin-5 and FLJ10540 expression.

Conclusion

Higher fibulin-5 expression is not only an important indicator of poor survival, but also contributes to the development of new therapeutic strategies in the FLJ10540/AKT pathway for NPC treatment.  相似文献   
265.
Mites are one of the serious pests of turfgrass. Our survey of turfgrass fields from 2013 to 2015 in Korea showed that the occurrence of leaf chlorotic symptom has gradually extended to at least 60% of the examined golf courses. We identified the zoysiae mite Aceria zoysiae in most damaged zoysiagrasses. Artificial infestation of A. zoysiae into zoysiagrasses in pots resulted in symptoms of chlorosis and marginal rolling of the leaves within 3 weeks. We firstly determined the nucleotide sequence of mitochondrial cytochrome c oxidase subunit I (COI) and internal transcribed spacer 2 (ITS2) of the nuclear ribosomal DNA region of A. zoysiae. The variations in COI and ITS2 between A. zoysiae and other species of the genus were 20.9%–43.0% and 7.5%–67.3%, respectively, suggesting significant genetic divergence within the genus. Our study provides valuable information for the rapid diagnosis and infestation monitoring of A. zoysiae in turfgrass fields.  相似文献   
266.
Chemokine receptor CCR5 is not only essential for chemotaxis of leukocytes but also has been shown to be a key coreceptor for HIV-1 infection. In the present study, hemagglutinin epitope-tagged human CCR5 receptor was stably expressed in Chinese hamster ovary cells or transiently expressed in NG108–15 cells to investigate CCR5-mediated signaling events. The surface expression of CCR5 was confirmed by flow cytometry analysis. The CCR5 agonist RANTES stimulated [35S]GTPγS binding to the cell membranes and induced inhibition on adenylyl cyclase activity in cells expressing CCR5. The effects of RANTES were CCR5 dependent and could be blocked by pertussis toxin. Furthermore, overexpression of Giα2 strongly increased both RANTES-dependent G-protein activation and inhibition on adenylyl cyclase in cells cotransfected with CCR5. These data demonstrated directly that activation of CCR5 stimulated membrane-associated inhibitory G proteins and indicated that CCR5 could functionally couple to G-protein subtype Giα2. The abilities of CCR5 to activate G protein and to inhibit cellular cAMP accumulation were significantly diminished after a brief prechallenge with RANTES, showing rapid desensitization of the receptor-mediated responsiveness. Prolonged exposure of the cells to RANTES caused significant reduction of surface CCR5 as measured by flow cytometry, indicative of agonist-dependent receptor internalization. Our data thus demonstrated that CCR5 functionally couples to membrane-associated inhibitory G proteins and undergoes agonist-dependent desensitization and internalization. J. Cell. Biochem. 71:36–45, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
267.
The striatum integrates motor behavior using a well‐defined microcircuit whose individual components are independently affected in several neurological diseases. The glial cell line‐derived neurotrophic factor (GDNF), synthesized by striatal interneurons, and Sonic hedgehog (Shh), produced by the dopaminergic neurons of the substantia nigra (DA SNpc), are both involved in the nigrostriatal maintenance but the reciprocal neurotrophic relationships among these neurons are only partially understood. To define the postnatal neurotrophic connections among fast‐spiking GABAergic interneurons (FS), cholinergic interneurons (ACh), and DA SNpc, we used a genetically induced mouse model of postnatal DA SNpc neurodegeneration and separately eliminated Smoothened (Smo), the obligatory transducer of Shh signaling, in striatal interneurons. We show that FS postnatal survival relies on DA SNpc and is independent of Shh signaling. On the contrary, Shh signaling but not dopaminergic striatal innervation is required to maintain ACh in the postnatal striatum. ACh are required for DA SNpc survival in a GDNF‐independent manner. These data demonstrate the existence of three parallel but interdependent neurotrophic relationships between SN and striatal interneurons, partially defined by Shh and GDNF. The definition of these new neurotrophic interactions opens the search for new molecules involved in the striatal modulatory circuit maintenance with potential therapeutic value.  相似文献   
268.
The aim of this study is to investigate the capability of an apoA-I mimetic with multiple amphipathic helices to form HDL-like particles in vitro and in vivo. To generate multivalent helices and to track the peptide mimetic, we have constructed a peptibody by fusing two tandem repeats of 4F peptide to the C terminus of a murine IgG Fc fragment. The resultant peptidbody, mFc-2X4F, dose-dependently promoted cholesterol efflux in vitro, and the efflux potency was superior to monomeric 4F peptide. Like apoA-I, mFc-2X4F stabilized ABCA1 in J774A.1 and THP1 cells. The peptibody formed larger HDL particles when incubated with cultured cells compared with those by apoA-I. Interestingly, when administered to mice, mFc-2X4F increased both pre-β and α-1 HDL subfractions. The lipid-bound mFc-2X4F was mostly in the α-1 migrating subfraction. Most importantly, mFc-2X4F and apoA-I were found to coexist in the same HDL particles formed in vivo. These data suggest that the apoA-I mimetic peptibody is capable of mimicking apoA-I to generate HDL particles. The peptibody and apoA-I may work cooperatively to generate larger HDL particles in vivo, either at the cholesterol efflux stage and/or via fusion of HDL particles that were generated by the peptibody and apoA-I individually.  相似文献   
269.
Campylobacter jejuni is a highly motile bacterium that responds via chemotaxis to environmental stimuli to migrate towards favourable conditions. Previous in silico analysis of the C. jejuni strain NCTC11168 genome sequence identified 10 open reading frames, tlp1‐10, that encode putative chemosensory receptors. We describe the characterization of the role and specificity of the Tlp1 chemoreceptor (Cj1506c). In vitro and in vivo models were used to determine if Tlp1 had a role in host colonization. The tlp1 isogenic mutant was more adherent in cell culture, however, showed reduced colonization ability in chickens. Specific interactions between the purified sensory domain of Tlp1 and l ‐aspartate were identified using an amino acid array and saturation transfer difference nuclear magnetic resonance spectroscopy. Chemotaxis assays showed differences between migration of wild‐type C. jejuni cells and that of a tlp1 isogenic mutant, specifically towards aspartate. Furthermore, using yeast two‐hybrid and three‐hybrid systems for analysis of protein–protein interactions, the cytoplasmic signalling domain of Tlp1 was found to preferentially interact with CheV, rather than the CheW homologue of the chemotaxis signalling pathway; this interaction was confirmed using immune precipitation assays. This is the first identification of an aspartate receptor in bacteria other than Escherichia coli and Salmonella enterica serovar Typhimurium.  相似文献   
270.
Auxin modulates a range of plant developmental processes including embryogenesis, organogenesis, and shoot and root development. Recent studies have shown that plant hormones also strongly influence metabolic networks, which results in altered growth phenotypes. Modulating auxin signalling pathways may therefore provide an opportunity to alter crop performance. Here, we performed a detailed physiological and metabolic characterization of tomato (Solanum lycopersicum) mutants with either increased (entire) or reduced (diageotropicadgt) auxin signalling to investigate the consequences of altered auxin signalling on photosynthesis, water use, and primary metabolism. We show that reduced auxin sensitivity in dgt led to anatomical and physiological modifications, including altered stomatal distribution along the leaf blade and reduced stomatal conductance, resulting in clear reductions in both photosynthesis and water loss in detached leaves. By contrast, plants with higher auxin sensitivity (entire) increased the photosynthetic capacity, as deduced by higher Vcmax and Jmax coupled with reduced stomatal limitation. Remarkably, our results demonstrate that auxin‐sensitive mutants (dgt) are characterized by impairments in the usage of starch that led to lower growth, most likely associated with decreased respiration. Collectively, our findings suggest that mutations in different components of the auxin signalling pathway specifically modulate photosynthetic and respiratory processes.  相似文献   
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