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71.
Tissue factor pathway inhibitor can interact with platelets   总被引:3,自引:0,他引:3  
Tissue factor pathway inhibitor (TFPI) regulates the extrinsic pathway of blood coagulation. However, there is no report on interaction between TFPI and platelets other than that by Tsuji, who found that whole blood anticoagulated with TFPI exhibited remarkable decrease in platelet count. Our study revealed that washed platelets suspended in modified Tyrode's buffer (8 mM CaCl2) containing TFPI exhibit platelet aggregation. However, platelets aggregation was observed without TFPI, but its increase and intensity were slow and weak, compared to that in the presence of TFPI. This aggregation was inhibited by anti-CD41 (anti-GPIIb) antibody. This finding suggested that TFPI promotes platelet aggregation.  相似文献   
72.
Mechanisms determining the chronicity or the pattern of clinical course of hepatitis C virus (HCV) infections have not been clarified. Recently, CD81 was reported to bind the E2 protein of HCV and was suggested to function as a cellular receptor for HCV. Accordingly, the hypothesis was examined that CD81 polymorphism, if it exists, might correlate with certain clinical courses of HCV infection. CD81 cDNA sequences were determined from peripheral blood mononuclear cells (PBMCs). Twenty-four Japanese subjects were enrolled initially as follows: patients with chronic hepatitis C without cirrhosis (n = 3), patients with cirrhosis (n = 3), patients with cirrhosis complicated by hepatocellular carcinoma (HCC) (n = 3), patients with persistent HCV viremia without ALT elevation (n = 3), those with positive anti-HCV antibodies without evidence of HCV viremia (n = 3), and healthy volunteers (n = 9). In all PBMCs samples analyzed, no polymorphism was found in the CD81 cDNA sequence. The sequence was different, however, from the one reported previously at three nucleotide positions: a transversion to thymine instead of cytosine at nt 1130, a deletion at nt 1206, and a guanine insertion at nt 71. Subsequently, CD81 cDNA sequences from PBMCs and HCC tissue were compared among the other 6 patients with chronic hepatitis C bearing HCC. A comparative study of the CD81 sequences from HCC and PBMCs revealed that various nucleotide mutations existed only in the HCC samples in 3 out of 6 patients. Several mutations in the 3' non-coding region of CD81 cDNA were observed exclusively in HCC tissue suggesting its possible role in hepatocarcinogenesis. Because of the absence of polymorphisms, however, CD81 is unlikely to affect the progression of chronic hepatitis C in terms of chronicity, hepatitis activity, or disease stage.  相似文献   
73.
Neuromedin B (NMB) is a mammalian bombesin (BN)-like peptide that exerts its function via the neuromedin B receptor (NMB-R). The NMB/NMB-R system is involved in stress response, and therefore we examined behavioral properties in female mice lacking NMB-R using a restraint-induced stress paradigm. Thirty minutes of restraint in a wire mesh cage constituted a sufficient stress stimulus for mice as evidenced by elevated blood glucose concentrations in stressed wild-type and NMB-R-deficient mice. Using a one-trial passive avoidance test, stressed NMB-R-deficient mice exhibited a marked reduction in memory performance. NMB-R-deficient mice exhibited elevated spontaneous activity in a novel environment compared to non-stressed mutant mice after 30-min stress, and a similar difference was also observed between stressed/non-stressed wild-type mice. An elevated plus maze test showed that the stress stimulus had no effect on anxiety in either wild-type or NMB-R-deficient mice. Furthermore, pain response of wild-type and NMB-R-deficient mice induced by electric foot shock was not affected under either stressed or non-stressed conditions. These results indicate that impaired memory performance in stressed NMB-R-deficient mice is not a consequence of changes in spontaneous activity, anxiety, or pain response, and suggest that the NMB/NMB-R pathway may play a role in regulating the stress response via the neural system that controls learning and memory.  相似文献   
74.
A rare case of rapidly growing osteosarcoma that developed in the uterine corpus of a 62-year-old woman is presented. The tumor occupied almost the entire pelvic cavity and extended into the abdominal cavity, with marked involvement of the intestines. Histopathologically, the tumor was composed of an osteoblastic component, accompanied by conspicuous bone formation, and a fibroblastic component. The tumor cells were positive for vimentin and osteocalcin, as well as desmin, alpha-smooth muscle actin and muscle-specific actin, but negative for h-caldesmon. The results indicated myofibroblastic differentiation in a part of the tumor. A review of 14 reported cases and our case of uterine osteosarcoma revealed that this tumor has a biologically aggressive nature, although its histopathological and immunohistochemical features are similar to those of osteosarcomas in soft tissue and bone. As the prognosis of patients with this tumor is poor, it is of importance to differentiate this tumor from other types of tumors arising from the uterine corpus.  相似文献   
75.
Interleukin-18 (IL-18) is one of the pivotal cytokines controlling the defense mechanism called inflammation. As a first step to develop proteins for controlling the IL-18 level, we initiated a study of IL-18-binding proteins (IL-18BPs). Twenty-four IL-18BP family members, 11 from vertebrates and 13 from chordopoxviruses, were picked from the NCBI database. Eight of these vertebrate IL-18BPs and two of the chordopoxvirus IL18-BPs were identified here and characterized as new members of the IL-18BP family. Their IL-18 binding domains were aligned and the distribution of highly conserved critical amino acid residues was analyzed and used to construct a phylogenetic tree. From this tree it was inferred that at least two independent events created two different ancestral viral IL-18BP genes by retroposition of IL-18BP genes from the vertebrate lineage. These two events are estimated to have occurred after an ancient mammalian IL-18BP gene diverged from birds, and before the mammalian IL-18BP gene diverged into human, ungulate and rodent IL-18BP genes. Moreover, our results suggest that IL-18BP and interleukin-1 receptor, type II (IL-1R2) had a common ancestral gene and diverged from the ancestral gene into IL-18BP and IL-1R2 genes in the fish period.  相似文献   
76.
Using the surgically extirpated specimens from 9 patients with colorectal carcinoma, fucosyltransferase activities in the carcinoma tissue and the normal mucosa were measured and were compared with the hlstochemical findings of glycoconjugates which were shown by staining with lectins reacting with blood group antigens and related substances. The fucosyltransferase activities of the carcinoma tissue were well correlated with the overall findings of lectin stainings after neuraminidase treatment. The more intense the carcinoma tissue was stained, the higher the fucosyltransferase activity was shown. However, there were marked differences in the fucosyltransferase activities by the portions measured, depending upon the relative amount of carcinoma tissue and Interstitial tissue; in the invasive portion with less carcinoma tissue, the activity was generally low in comparison with that in the surface area where carcinoma tissue was rather abundant. Thus, the morphological and lectin hlstochemical finding are of paramount importance for the eveluation of glycosyltransferase activity in human colorectal carcinoma.  相似文献   
77.
78.
This study examined the effects of voluntary abdominal breathing (VAB) on the electroencephalogram (EEG) in 22 healthy subjects. VAB was characterized by prolonged rhythmic contraction of abdominal muscles for 20 min in an eyes-closed condition. The breathing rate was instructed to be very slow, i.e., 3-4 breaths/min (inspiratory time for 6-8s and expiratory time for 9-12s). A low-frequency alpha band appeared immediately after eye closing, but it later disappeared and was replaced by a new development of a high-frequency alpha band 4-5 min after the onset of VAB. The subjects had a feeling of vigor-activity with a tendency of reduced anxiety during and/or after VAB, as assessed by POMS and STAI questionnaire scores. On the other hand, during resting in the eye-closed condition, the disappearance of the low-frequency alpha band was replaced by the occurrence of a theta/delta band. The subjects became drowsy in this condition. We therefore conclude that the increase in high-frequency alpha activity is linked to the state of vigor-activity with a tendency of reduced anxiety. Since the urinary serotonergic level significantly increased after the VAB, we suggest that the serotonergic neurons within the brain may produce the changes in the EEG patterns.  相似文献   
79.
In bovine retinal microvessels, alpha 1, alpha 2- and beta-adrenergic receptors were characterized by binding assay, using [3H]prazosin, [3H]para-aminoclonidine and [125I]iodocyanopindolol as radioligands, respectively. The microvessels were purified from bovine eyes by differential centrifugation through a high concentration of bovine serum albumin followed by use of a glass bead filtration technique. In the preparation, specific binding sites for [3H]para-aminoclonidine and [125I]iodocyanopindolol were observed, whereas [3H]prazosin binding was not detected. The [3H]para-aminoclonidine binding sites localized to the microvessels were characterized by high affinity and saturability (KD: 173 +/- 9 pM; Bmax: 394 +/- 11 fmol/mg protein) as well as the [125I]iodocyanopindolol binding sites (KD: 20 +/- 3 pM; Bmax: 43 +/- 4 fmol/mg protein). Furthermore, the specificity of both binding sites was pharmacologically evaluated by measuring the inhibitory effects of various adrenergic reagents on binding. The existence of alpha 2- and beta-adrenergic receptors which were characterized by high affinity, saturability and stereospecificity, leads to the hypothesis that the retinal microcirculation is under neuronal control.  相似文献   
80.
The gene expression array method enables us to achieve expression profiling with thousands of genes. Clinically resected bulk cancer tissues, however, contain not only cancer cells but also stromal cells, which may affect gene expression profiling and hamper accurate analysis of the cancer cells per se. Therefore, a procedure for dissecting specific cells, such as laser capture microdissection, is neededfor the clinical application of a gene expression array. There has been no study actually comparing 2 gene expression profiles, one obtained using RNA extractedfrom cancer cells by laser capture microdissection and one obtained using RNA extractedfrom bulk cancer tissues. Wefirst demonstrated the difference in expression patterns between them, without any amplification procedures. In addition, differential expression analysis between tumor and nontumor tissue yielded quite different patterns between the 2 methods. We conclude that microdissection is essential for gene expression profiling of clinical specimens.  相似文献   
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