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61.
62.
To develop a new measurement tool for quantitatively detecting the finger movement of a patient with Parkinson's disease (PD), we designed a magnetic sensing system consisting of a magnetic induction coil, a sensing coil, and a circuit unit. The sensing coil detects the inducted magnetic field that varies with the distance between the two coils, and the detected signals are demodulated in the circuit unit in order to obtain the variation voltage from the oscillation frequency. To obtain a coefficient for converting voltage to distance, we measured the output voltages for seven fixed finger positions of 12 normal volunteers. The voltage differences corresponding to the finger movement in 20 PD patients, six age-matched controls, and 12 normal volunteers were then recorded for 30s. To investigate the velocity and acceleration of the finger movement, we calculated their waveforms from the measured displacement waveform. We also detected the main frequency of the tapping rhythm by using a fast Fourier transform (FFT). The averaged amplitude of each waveform decreased with the disorder in the Hoehn-Yahr (HY) stage, while the averaged tapping frequency of PD patients did not have any correlation with this stage. It can be concluded that this magnetic sensing system can assess finger movement quantitatively.  相似文献   
63.
In acute hypotension, an automated drug infusion system to control mean arterial blood pressure (MAP) has not been previously studied, though many investigations have examined the use of vasodilating drugs to control MAP in postoperative hypertension. Therefore, we examined an automated control of MAP during acute hypotension using a neural network (NN) approach. A proportional-integral-derivative (PID) control, an adaptive predictive control using a NN (APC(NN)), a combined control of APC(NN) and PID (APC(NN-PID)), a fuzzy control, and a model predictive control were tested in computer simulation based on the MAP response to norepinephrine (NE) of 25 microg ml(-1). In six anesthetized rabbits, using the NE of 25 microg ml(-1), the PID control, APC(NN), and APC(NN-PID) prevented severe hypotension compared to an uncontrolled condition. Under PID control, four of the six animals showed MAP oscillation. Using NE of 50 microg ml(-1), the rabbits recovered from acute hypotension for all systems tested but showed sustained MAP oscillation during PID control. In conclusion, utilization of a NN for adaptive predictive control systems could facilitate the development of an automated drug infusion apparatus because it provides robust control even when acute or large perturbations and inter-individual differences in the sensitivity to therapeutic agents occur.  相似文献   
64.
Tocopherol-associated protein (TAP) was expressed in mouse mast cells. TAP was predominantly localized in the cytoplasm, and the subcellular localization was not changed by alpha-tocopherol. The results suggest that the physiological role of TAP in mast cells is not regulation of tocopherol function but an as-yet-unidentified activity.  相似文献   
65.
66.
The response of chronic hepatitis C to interferon (IFN) treatment is classified as complete response (CR), biochemical response (BR), or no response (NR). Several studies have found no difference in prevention of hepatocellular carcinoma by IFN therapy between patients with CR and those with BR. We investigated whether specific human leukocyte antigen (HLA) alleles were associated with response to IFN, especially BR, in 138 patients with chronic hepatitis C. Comparing patients with and without CR, male, a low viral titer, genotype 2a or 2b, HLA-B55, and HLA-DRB1-0803 were more common in the group with CR. Multivariate analysis showed that age (adjusted odds ratio [OR], 0.95 by every year [95% confidence interval [CI] 0.90 - 0.99], p = 0.028), genotype 2a or 2b (5.21 [95% CI 1.63 - 16.6], p = 0.005), and low viral titer (8.58 (2.66 - 27.7), p < 0.001) were associated with CR. Comparing patients with BR and NR, the pretreatment alanine aminotransferase (ALT) level was lower in the BR group (p < 0.001). Both HLA-B7 and HLA-DRB1-0101 were more common in this group (p = 0.002). As the alleles HLA-B7 and HLA-DRB1-0101 were in linkage disequilibrium, the HLA-B7-DRB1-0101 haplotype may be associated with BR. Multivariate analysis indicated that a low ALT level (0.98 by every 1 IU/L [95% CI 0.98 - 0.99], p = 0.001) and HLA-B7-DRB1-0101 haplotype (32.3 [95% CI 1.50 - 693.1], p = 0.026) contributed significantly to BR. This study suggested that host HLA expression, but not viral factors, can influence BR.  相似文献   
67.
Clinically important fungi such as Candida albicans and Cryptococcus neoformans are known to undergo phenotypic changes after repeated subculture or passages in vivo. However, there are no reports describing this phenomenon in Trichosporon species. This study investigated whether in-vivo passages of environmental isolates of Trichosporon asahii in mice changes their phenotype; three environmental isolates and 14 clinical isolates (from deep-seated infections) were used. The shape of the colony and cell type were observed, and the titre of glucuronoxylomannan (GXM) antigen and concentration of (1-->3)-beta-D-glucan were measured for each isolate. Changes in these features were also examined after three passages of the environmental isolates in mice. The shape of colonies and cell types were clearly different in environmental and clinical isolates. Furthermore, the clinical isolates released significantly higher levels of GXM antigen than environmental isolates (titre: log2 9.4 SD 0.7 versus log2 5.4 SD 1.4). The phenotype of passaged isolates was significantly different from the original environmental isolates with respect to the morphology of colonies and cell type and GXM release (titre: log2 10.0 SD 0.7 versus log2 5.4 SD 1.4). These results suggest that the phenotypic changes in T. asahii occur as a result of in-vivo passages. This process may allow a proportion of the fungal population to escape eradication by the host immune system, as GXM antigen is considered to protect the fungi against phagocytosis by polymorphonuclear leucocytes and monocytes in vivo.  相似文献   
68.
Histologically, the marginal zone pattern of the lymph node is characterized by lymphoid follicles with three distinct layers. The inner layer is composed of follicular center zones, the middle layer of darkly stained mantle zones, and the outer layer of marginal zones. However, the marginal zone pattern is rarely seen in reactive lymph nodes except for mesenteric lymph nodes. We describe the clinicopathologic, immunohistochemical and genotypic findings of six cases of reactive follicular hyperplasia exhibiting the marginal zone pattern. The patients comprised three males and three females (age range 24 to 63 years; medium 56 years). Follow-up data were obtained from five patients. None of them developed malignant lymphomas during the follow-up period of from 5 to 204 months (median 68 months). Histologically, the lesion was characterized by numerous lymphoid follicles and partial distortion of lymph node structure. Varying degrees of progressive transformation of the germinal center (PTGC) were noted in the four cases. The marginal zone pattern was observed in some or most of the lymphoid follicles including PTGC. The marginal zone B cells were small to medium-sized lymphocytes with round or slightly indented nuclei and a broad rim of pale cytoplasm. Some of them had a monocytoid appearance. They were CD20+, CD79a+, sIgM+/-, sIgD-, CD5-, CD10-, CD21-, CD23-, CD43-, CD45RO-, Bcl-6-, cyclin D1-, EMA- and p53-. A portion of them were Bcl-2 positive. Occasional large lymphoid cells with round or indented nuclei and moderate amounts of cytoplasm were observed in the marginal zone in four cases. These large lymphoid cells were usually CD20 positive, but Bcl-6 negative. A small number of them contained polytypic intracytoplasmic immunoglobulins. The polytypic nature of B lymphocytes was demonstrated by immunohistochemistry and polymerase chain reaction. Recognition of unusual marginal zone hyperplasia in reactive lymph node lesions is important to avoid confusion with nodal involvement in various low-grade B cell lymphomas presenting a marginal zone distribution pattern.  相似文献   
69.
BACKGROUND: Relationship between post administrative changes in plasma drug levels and bronchodilation remains unknown. In this study, we measured plasma levels of procaterol, a beta2-agonist, when being inhaled through nebulizers in children with bronchial asthma to examine relationship between improvement of pulmonary function and the plasma levels. METHOD: Six asthmatic children with the mean age of 9.8 years, inhaled 0.3 ml of 0.01% procaterol solution through a nebulizer. We examined changes in pulmonary function and plasma procaterol levels before and after inhalation. RESULTS: Procaterol was detected in the plasma 2 minutes after inhalation when it already rose to the maximum level, and kept the steady until showing a decline in 30 minutes. The measured highest value was 87.8+/-45.1 pg/ml. FEV 1.0 remarkably increased 2 minutes after inhalation and was maintained until 60 minutes after inhalation. Other lung function parameters also improved. There was no significant change in the heart rate, but serum potassium concentrations significantly dropped in all patients 60 minutes after inhalation. CONCLUSION: Plasma procaterol levels promptly rose to the peak at 2 minutes after inhalation and decreased 30 minutes later. Improvement of pulmonary function started promptly at minutes after inhalation and it became a peak 60 minutes later.  相似文献   
70.
We examined the production of macrophage-derived chemokine (MDC/CCL22) and thymus- and activation-regulated chemokine (TARC/CCL17) by bronchoalveolar lavage fluid (BALF) cells in cigarette-smoke-associated acute eosinophilic pneumonia (CS-AEP). The CC Chemokine Receptor 4 (CCR4) ligand levels in BALF from patients with CS-AEP were considerably higher than those in healthy volunteers and correlated well with Th2 cytokine levels. Interleukin-4 enhanced CCR4 ligand production. MDC expression was observed in CD68-positive cells from patients with CS-AEP and in healthy control smokers. In contrast, TARC expression in CD68- or CD1a-positive cells was detected only in CS-AEP. An in vivo cigarette smoke challenge test induced increases in CCR4 ligands in the BALF and in the cultured supernatant of BALF adherent cells. These results suggest that alveolar macrophages and dendritic cells contribute to the pathogenesis of CS-AEP by generating CCR4 ligands, probably in response to cigarette smoke.  相似文献   
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