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51.
Although participatory workplace improvement programs are known to provide favorable effects on high stress occupations like nursing, no studies have confirmed its effect using biomarkers. The aim of this study was to determine whether a participatory workplace improvement program would decrease stress-related symptoms as evaluated by biomarkers and self-reported stress among hospital nurses. Three actions to alleviate job stress, which were determined through focus group interviews and voting, were undertaken for two months. A total of 31 female Japanese nurses underwent measurement of inflammatory markers, autonomic nervous activity (ANA), and perceived job stress (PJS) at three-time points; before the program (T1), within a week after the completion of the program (T2), and three months after the program (T3). A series of inflammatory markers (Interferon-γ, Interleukin (IL)-6, and IL-12/23p40) decreased significantly at T2, and IL-12/23p40 and IL-15 significantly decreased at T3 compared to T1, while ANA and PJS remained unchanged. Our participatory program exerted beneficial effects in reducing inflammatory responses, but not for ANA and PJS. Further investigations with a better study design, i.e., a randomized controlled trial, and a larger sample size are warranted to determine what exerted beneficial effects on inflammatory markers and why other outcomes remained unchanged.  相似文献   
52.
Vaccine adjuvants are compounds that enhance/prolong the immune response to a co-administered antigen. Saponins have been widely used as adjuvants for many years in several vaccines – especially for intracellular pathogens – including the recent and somewhat revolutionary malaria and shingles vaccines. In view of the immunoadjuvant potential of Q. brasiliensis saponins, the present study aimed to characterize the QB-80 saponin-rich fraction and a nanoadjuvant prepared with QB-80 and lipids (IMXQB-80). In addition, the performance of such adjuvants was examined in experimental inactivated vaccines against Zika virus (ZIKV). Analysis of QB-80 by DI-ESI-ToF by negative ion electrospray revealed over 29 saponins that could be assigned to known structures existing in their congener Q. saponaria, including the well-studied QS-21 and QS-7. The QB-80 saponins were a micrOTOF able to self-assembly with lipids in ISCOM-like nanoparticles with diameters of approximately 43 nm, here named IMXQB-80. Toxicity assays revealed that QB-80 saponins did present some haemolytical and cytotoxic potentials; however, these were abrogated in IMXQB-80 nanoparticles. Regarding the adjuvant activity, QB-80 and IMXQB-80 significantly enhanced serum levels of anti-Zika virus IgG and subtypes (IgG1, IgG2b, IgG2c) as well as neutralized antibodies when compared to an unadjuvanted vaccine. Furthermore, the nanoadjuvant IMXQB-80 was as effective as QB-80 in stimulating immune responses, yet requiring fourfold less saponins to induce the equivalent stimuli, and with less toxicity. These findings reveal that the saponin fraction QB-80, and particularly the IMXQB-80 nanoadjuvant, are safe and capable of potentializing immune responses when used as adjuvants in experimental ZIKV vaccines.  相似文献   
53.
Vascular Ehlers–Danlos syndrome (vEDS) is a hereditary connective tissue disorder (HCTD) characterized by arterial dissection/aneurysm/rupture, sigmoid colon rupture, or uterine rupture. Diagnosis is confirmed by detecting heterozygous variants in COL3A1. This is the largest Asian case series and the first to apply an amplification-based next-generation sequencing through custom panels of causative genes for HCTDs, including a specific method of evaluating copy number variations. Among 429 patients with suspected HCTDs analyzed, 101 were suspected to have vEDS, and 33 of them (32.4%) were found to have COL3A1 variants. Two patients with a clinical diagnosis of Loeys–Dietz syndrome and/or familial thoracic aortic aneurysm and dissection were also found to have COL3A1 variants. Twenty cases (57.1%) had missense variants leading to glycine (Gly) substitutions in the triple helical domain, one (2.9%) had a missense variant leading to non-Gly substitution in this domain, eight (22.9%) had splice site alterations, three (8.6%) had nonsense variants, two (5.7%) had in-frame deletions, and one (2.9%) had a multi-exon deletion, including two deceased patients analyzed with formalin-fixed and paraffin-embedded samples. This is a clinically useful system to detect a wide spectrum of variants from various types of samples.  相似文献   
54.
  1. Desensitization of μ- and κ-opioid receptor-mediated inhibition of voltage-dependent Ca2+ channels was studied in a Xenopus oocyte translation system.
  2. In the oocytes coexpressing κ-opioid receptors with N- or Q-type Ca2+ channel α1 and β subunits, the κ-agonist, U50488H, inhibited both neuronal Ca2+ channel current responses in a pertussis toxin-sensitive manner and the inhibition was reduced by prolonged agonist exposure.
  3. More than 10 min was required to halve the inhibition of Q-type channels by the κ-agonist. However, the half-life for the inhibition of N-type channels was only 6±1 min. In addition, in the oocytes coexpressing μ-opioid receptors with N-type or Q-type channels, the uncoupling rate of the μ-receptor-mediated inhibition of N-channels was also faster than that of Q-type channels.
  4. In the oocytes coexpressing both μ- and κ-receptors with N-type channels, stimulation of either receptor resulted in a cross-desensitization of the subsequent response to the other agonist. Treatment of oocytes with either H-8 (100 μM), staurosporine (400 nM), okadaic acid (200 nM), phorbol myristate acetate (5 nM) or forskolin (50 μM) plus phosphodiesterase inhibitor did not affect either the desensitization or the agonist-evoked inhibition of Ca2+ channels.
  5. These results suggest that the rate of rapid desensitization is dependent on the α1 subtype of the neuronal Ca2+ channel, and that a common phosphorylation-independent mechanism underlies the heterologous desensitization between opioid receptor subtypes.
  相似文献   
55.
Axonal and glial reactions to traumatic injury were compared between the caudal and rostral border of the lesion after freeze-injury to the C3 dorsal funiculus by attaching a liquid nitrogen-cooled copper probe to the dorsum of the rat spinal cord. The axonal and glial changes were examined up to 60 days postoperative by light and electron microscopy and immunohistochemistry for neurofilaments. Regenerative axonal changes and the appearance of numerous undifferentiated cells were found at the caudal border 7 days after cryoinjury. In contrast, such axonal and cellular reactions were scarce at the rostral border. Undifferentiated cells clearly manifested their phenotypes by differentiating into oligodendrocytes or astrocytes 11 days postinjury. The results indicated that glial cell reactions occurred in association with regenerative axonal changes at the proximal stump of the injured nerve fibers, suggesting that regenerating and demyelinated naked axons could be responsible for the appearance of the immature glial cells.  相似文献   
56.
This review describes the historical development of aesthetic surgery in Japan and parallels with the development of the specialty in the United States. The focus is on the consequences of aesthetic surgery in the male patient when collaboration between mental health clinicians and surgeons lags. The cultural, social, and psychological issues raised are relevant to the diverse cultural groups now seeking aesthetic surgery in the United States. Case illustrations are a reminder to aesthetic surgeons of the potential need for more comprehensive evaluation in the group of male patients who may be at added risk for negative outcomes in terms of satisfaction.  相似文献   
57.
We established a cell line with high metastatic potential to the liver (LS-LM4) after four successive repetitions of splenic injection of liver-metastatic cells in SCID mice. This cell line strongly expressed CEA and showed increased homotypic adhesion as compared with the parent cell line (LS174T). To examine the role of CEA in the increased homotypic adhesion, LS-LM4 cells were treated with anti-CEA antibody and subjected to an in vitro adhesion and aggregation assay. Further, to study the role of CEA in the hepatic metastasis of cells with high metastatic potential, LS-LM4 cells were treated with anti-CEA antibody, and the inhibition of hepatic metastasis after splenic injection in vivo was examined. There was a 62% decrease in the homotypic adhesion of anti-CEA antibody-treated (100 μg/ml) LS-LM4 cells under a Ca2+-free condition as compared with the control ( P <0.01). Anti-CEA antibody (100 μg/ml) inhibited cell aggregation under a Ca2+-free condition ( P <0.05). Treatment with anti-E-cadherin antibody (60 μ/ml) plus anti-CEA antibody (100 μg/ml) inhibited cell aggregation more potently than anti-E-cadherin antibody treatment alone in the presence of Ca2+. In vivo , there was a 75% decrease in the number of hepatic metastatic nodules in the G125 anti-CEA antibody-treated group as compared with the control group ( P <0.01). Similarly, there was a 40% decrease in the diameter of metastatic nodules and there was a 90% decrease in total tumor volume of hepatic metastasis in the G125 anti-CEA antibody-treated group as compared with the control ( P <0.01). These results suggest that increased metastatic potential to the liver is at least partly due to increased homotypic binding mediated by CEA.  相似文献   
58.
PURPOSE: LATS1 and LATS2 are tumor suppressor genes implicated in the regulation of cell cycle. Methylation status of the promoter regions of these genes as well as its correlation with their mRNA levels were studied in human breast cancers. Correlation of LATS1 and LATS2 mRNA levels with clinicopathologic characteristics of breast tumors were also studied. EXPERIMENTAL DESIGN: Methylation status of promoter regions of LATS1 and LATS2 was studied by a methylation-specific PCR and mRNA expression levels of LATS1 and LATS2 were determined by a real-time PCR assay in 30 breast cancers. In addition, correlation of LATS1 and LATS2 mRNA levels with clinicopathologic characteristics was studied in 117 breast cancers. RESULTS: Methylation-specific PCR showed that of 30 tumors, LATS1 promoter region was hypermethylated in 17 tumors (56.7%) and LATS2 promoter region was hypermethylated in 15 (50.0%) tumors. LATS1 mRNA levels in breast tumors with hypermethylation (2.15 +/- 0.37, mean +/- SE) were significantly (P < 0.01) lower than those without hypermethylation (6.09 +/- 1.38), and LATS2 mRNA levels in breast tumors with hypermethylation (1.42 +/- 0.66) were also significantly (P < 0.01) lower than those without hypermethylation (3.10 +/- 1.00). The decreased expression of LATS1 or LATS2 mRNA was significantly associated with a large tumor size, high lymph node metastasis, and estrogen receptor and progesterone receptor negativity. Furthermore, the decreased expression of LATS1 mRNA, but not LATS2 mRNA, was significantly (P < 0.05) associated with a poor prognosis. CONCLUSIONS: Hypermethylation of the promoter regions of LATS1 and LATS2 likely plays an important role in the down-regulation of their mRNA levels in breast cancers, and breast cancers with a decreased expression of LATS1 or LATS2 mRNA levels have a biologically aggressive phenotype.  相似文献   
59.
Two forms of complement-depleting cobra venom factor (CVFm1 and CVFm2), possessing molecular masses of 142.6 kDa (CVFm1) and 143.1 kDa (CVFm2), according to MALDI mass-spectrometry, were isolated from the Naja melanoleuca cobra venom. As shown by polyacrylamide gel electrophoresis in the presence of SDS, both forms similarly to factor from the Naja kaouthia cobra venom (CVFk) consist of three polypeptide chains with molecular masses of about 70, 50, and 30 kDa, the two large subunits being glycosylated. As determined by MALDI mass-spectrometry, 30 kDa subunits of CVFm1 and CVFm2 have considerably different finger-prints of tryptic digests that suggests differences in their amino acid sequences. A study of activity in vivo has shown no significant differences in C3 consumption by CVFm1, CVFm2 and CVFk in mouse blood. However, as shown by an immunoassay method, they differ in their ability to activate the complement system via C3 conversion, the ratio of these activities for CVFm1:CVFm2:CVFk being 2.5:1.6:1. Kinetic studies using a hemolytic test showed that complement depletion by CVFm1 is faster than that by CVFm2. Thus, for the first time the presence in a single venom of two forms of CVF differing by both amino acid sequence and biological activity has been shown.  相似文献   
60.
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