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81.
PROBLEM: Tumor necrosis factor (TNF)-alpha is a major cytokine involved in inflammatory and immune function. The aim of this study was to investigate whether polymorphisms at positions -1031, -863 and -857 in the TNF gene promoter region (TNFA) and TNF receptor type 2 gene (TNFR2) are responsible in part for genetic susceptibility to endometriosis. METHODS OF STUDY: TNFA and TNFR2 polymorphisms were determined in 123 patients with endometriosis and 165 fertile healthy women by the polymerase chain reaction (PCR) - preferential homoduplex formation assay and PCR-restriction fragment length polymorphism, respectively. RESULTS: The frequency of the TNFA-U01 haplotype was increased significantly in patients with endometriosis compared with controls (P = 0.045, OR = 1.45). The TNFA-U01 haplotype was strongly associated with HLA-B*0702. No difference was found in TNFR2 polymorphism between patients and controls. CONCLUSION: Our results indicated that TNFA promoter polymorphism was associated with susceptibility to endometriosis. However, this association was not independent of HLA-class I polymorphisms.  相似文献   
82.
Effects of focus on a target word during performance of the reading span test (RST) were investigated. A focus word in the sentence was defined as the most critical word with a core meaning to integrate the sentence. Two kinds of RST were compared. One was focus-RST (F-RST) in which the target word to be maintained was a focus word of the sentence. The other was a non-focus-RST (NF-RST) in which the target word was not a focus word of the sentence, although the sentence did contain a focus word. Results showed that RST scores were found to be higher for F-RST than for NF-RST. Moreover, the effect of focus was proved to be dominant for low span subjects. Intrusion errors also increased in NF-RST. Sentence length effect, however, was not found. The results showed that low span subjects had severe deficits in making and updating the focus, which is critical for sentence comprehension.  相似文献   
83.
It has been suggested that vitamin B12 (vit.B12) plays an important role in immune system regulation, but the details are still obscure. In order to examine the action of vit.B12 on cells of the human immune system, lymphocyte subpopulations and NK cell activity were evaluated in 11 patients with vit.B12 deficiency anaemia and in 13 control subjects. Decreases in the number of lymphocytes and CD8+ cells and in the proportion of CD4+ cells, an abnormally high CD4/CD8 ratio, and suppressed NK cell activity were noted in patients compared with control subjects. In all 11 patients and eight control subjects, these immune parameters were evaluated before and after methyl-B12 injection. The lymphocyte counts and number of CD8+ cells increased both in patients and in control subjects. The high CD4/CD8 ratio and suppressed NK cell activity were improved by methyl-B12 treatment. Augmentation of CD3-CD16+ cells occurred in patients after methyl-B12 treatment. In contrast, antibody-dependent cell-mediated cytotoxicity (ADCC) activity, lectin-stimulated lymphocyte blast formation, and serum levels of immunoglobulins were not changed by methyl-B12 treatment. These results indicate that vit.B12 might play an important role in cellular immunity, especially relativing to CD8+ cells and the NK cell system, which suggests effects on cytotoxic cells. We conclude that vit.B12 acts as an immunomodulator for cellular immunity.  相似文献   
84.
Before the early 1990s, the diagnostic usefulness of echocardiography for ischemic heart disease had been relatively limited compared with that for other cardiac diseases such as valvular disease, congenital anomalies and cardiomyopathies. The principal role of echocardiography was to assess persistent regional wall motion abnormality as well as to detect complications of myocardial infarction. However, recent technological advances have created many newer applications of echocardiography in this field. One of the most important advances was seen in the field of stress echocardiography. Dobutamine stress echocardiography has become an established method of diagnosing transient myocardial ischemia due to coronary stenosis and assessing the myocardial viability of a persistently akinetic segment. More recently, several new contrast agents have been developed or will be available in the near future to visualize the blood stream within the left heart cavity and myocardial blood flow. Simultaneously, new ultrasound technologies including harmonic imaging and gated intermittent imaging have enhanced the selective visualization of contrast agents and will contribute to noninvasive imaging of coronary microcirculation. Harmonic imaging has also been shown to improve quality of B-mode image without a contrast agent and will play an important role in the clinical recognition of wall motion abnormality in patients with ischemic heart disease. Recent advances in three-dimensional technology have enabled accurate measurements of left ventricular volume and ejection fraction without any geometrical assumption, which may be especially important for the evaluation of ischemic patients who often have a deformed left ventricular cavity due to remodeling.  相似文献   
85.
The content of 5-hydroxytryptamine (5HT) in various tissues of mutant mouse (W/W v) deficient in mast cells and of control mouse (+/+) was determined by high performance liquid chromatography. The depletion of mast cells in the mutant mouse (W/W v) was expected to cause a decrease in the 5HT content. In the control mice, 5HT was most densely accumulated in the lung (9.66±5.23 g/g). Large intestine (6.40±2.61 g/g) and stomach (6.10±2.14 g/g) followed the lung in the rating of the 5HT content. The 5HT content ofW/W v mice was only 23.4% and 4.1% that of the control in the stomach (p<0.01) and the skin (p<0.01), respectively. The results were consistent with the expectation. In other organs (small intestine, caecum, large intestine, brain, lung, blood and salivary gland), the difference between theW/W v and normal mice was not statistically significant. The difference in the 5HT content of the stomach between the two genotypes was 4.67 g/g and was much larger than the 5HT content (0.49g/g) of normal mouse skin. With regard to the relatively small number of mast cells present in the stomach, the great difference in the 5HT content in the stomach between the two genotypes cannot be explained by the loss of mast cells. Hence, besides mast cells other cells may contribute to the high 5HT content of the stomach.This work was supported in part by grants from Takeda Science Foundation (1982), from the Ministry of Education, Science and Culture of Japan (Grant-in-Aid for Special Project Research. 1981–83) and from National Center of Nervous, Mental and Muscular Disorders (NCNMMD) of the Ministry of Health and Welfare, Japan (1981–83).To whom correspondence should be addressed  相似文献   
86.
We previously reported that ligand-independent signaling by highly expressed CD30 in Hodgkin-Reed-Sternberg (H-RS) cells is responsible for constitutive activation of NF-kappa B. In the present study, we characterize the intracellular localization of tumor necrosis factor (TNF) receptor associated factor (TRAF) proteins in H-RS cells. Confocal immunofluorescence microscopy of cell lines derived from H-RS cells and HEK293 transformants highly expressing CD30 revealed aggregation of TRAF2 and TRAF5 in the cytoplasm as well as clustering near the cell membrane. In contrast, TRAF proteins were diffusely distributed in the cytoplasm in cell lines unrelated to Hodgkin's disease (HD) and control HEK293 cells. Furthermore, the same intracellular distribution of TRAF proteins was demonstrated in H-RS cells of lymph nodes of HD, but not in lymphoma cells in lymph nodes of non-Hodgkin's lymphoma. Dominant-negative TRAF2 and TRAF5 suppressed cytoplasmic aggregation along with constitutive NF-kappa B activation in H-RS cell lines. Confocal immunofluorescence microscopy also revealed co-localization of IKK alpha, NIK, and I kappa B alpha with aggregated TRAF proteins in H-RS cell lines. These results suggest involvement of TRAF protein aggregation in the signaling process of highly expressed CD30 and suggest they function as scaffolding proteins. Thus, cytoplasmic aggregation of TRAF proteins appears to reflect constitutive CD30 signaling which is characteristic of H-RS cells.  相似文献   
87.
Effects of long-term administration of 1,2,3,4-tetrahydroisoquinoline (TIQ) on the striatal dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) were investigated in mice and rats. Striatal dopamine content significantly increased and DOPAC decreased after repeated administrations of TIQ at a dose of 50 mg/kg/day s.c. for 70 days in mice. In contrast, dopamine and DOPAC content did not show any significant change in rats. The ratio DOPAC/dopamine decreased significantly in mice treated with TIQ for 70 days. The results presented suggest that TIQ reduces the turnover rate of the nigrostriatal dopamine neurons after repeated administration for a long period in mice.  相似文献   
88.
Prader-Willi syndrome (PWS) and Angelman syndrome (AS) are distinct mental retardation disorders associated with deletions of proximal 15q (q11-q13) of different parental origin. Yeast artificial chromosome (YAC) clones were isolated for 9 previously mapped DNA probes from this region, and for one newly derived marker, LS6-1 (D15S113). A YAC contig of 1-1.5 Mb encompassing four markers (ML34, IR4-3R, PW71, and TD189-1) was constructed. Multi-color fluorescence in situ hybridization (FISH) analysis of interphase nuclei was combined with YAC contig information to provide the following order of markers: cen-IR39-ML34-IR4-3R-PW71-TD189-1-LS6++ +-1-TD3-21-GABRB3-IR10-1-CMW1-tel. FISH analysis was performed on 8 cases of PWS and 3 cases of AS, including 5 patients with normal karyotypes. All eleven patients were deleted for YACs in the interval from IR4-3R to GABRB3. On the proximal side of the deletion interval, 10/10 breakpoints fell within a single ML34 YAC of 370 kb. On the distal side, 8/9 breakpoints fell within a single IR10-1 YAC of 200 kb. These results indicate a striking consistency in the location of the proximal and distal breakpoints in PWS and AS patients. FISH analysis on a previously reported case of familial AS confirmed a submicroscopic deletion including YACs corresponding to LS6-1, TD3-21 and GABRB3 and supports the separation of the PWS and AS critical regions. Since these three YACs do not overlap each other, the minimum size of the AS critical region is > or = 650 kb.  相似文献   
89.
Studies on the fragments of FDP in 4 patients with DIC]   总被引:1,自引:0,他引:1  
We previously studied fibrinolysis and fibrinogenolysis by analyzing fragments of fibrin/fibrinogen degradation products (FDP) employing sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. In this report, we characterized the fragments of FDP in four patients with disseminated intravascular coagulation (DIC), that were caused by various diseases. In the patients suffering from acute lymphoblastic leukemia (case 1) and acute suppurative cholangitis (case 3), DD and DY/X fragments resulting from fibrinolysis accounted for the most part of the FDP fragments. In case 3, D fragments resulting from fibrinogenolysis were also observed to much less extent. In a DIC associated with acute myeloblastic leukemia (case 2), both fibrinolysis and fibrinogenolysis were increased and resulted in high levels of D, Y and DY/X fragments, concomitant with moderate levels of DD and high molecular weight (HMW) fragments in the patient's sera. The increased fibrinogenolysis in this case was attributed to accelerated activation of plasmin. In a DIC patient of case 4, who underwent an operation due to hepatocellular carcinoma, marked increase in DY/X and HMW fragments and slight increase in DD fragment were observed on the day of operation. Hyperfibrinolysis documented in case 4 was explained by both increased production of thrombin and moderately accelerated activation of plasmin. Both qualitative and quantitative changes in the fragments of FDP during the courses of treatment in two cases of DIC were also noted. In summary, each underlying disease expresses characteristic pattern of FDP fragments in DIC.  相似文献   
90.
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