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91.
Clinical Rheumatology - Articular cartilage and periarticular muscle tissues are strongly affected during knee osteoarthritis (OA). Creatine kinase (CK) is an enzyme expressed in several tissues,...  相似文献   
92.
Gastric lesions secondary to long-distance running   总被引:3,自引:0,他引:3  
Gastrointestinal disorders have been reported during long- distance running. The purpose of this study was to evaluate the effects of prolonged exercise on the upper digestive tract. Seven subjects were submitted to a standard endoscopic examination of the upper digestive tract before and after long- distance running (range 18– 50 km). Mucosal biopsy specimens were taken during all endoscopies. After running, all runners had histologically pathological features in the stomach. Vascular lesions were present in the chorion in six subjects after running, with the intensity of the lesions ranging from congestion to hemorrhage. Postexercise histological examination also showed a decrease in mucosal secretion. These lesions secondary to prolonged exercise indicate the presence of hemodynamic perturbations in the upper digestive tract.  相似文献   
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94.
The adhesion of haematopoietic progenitor cells (HPC) to the bone marrow microenvironment is a process regulated by cytokines. In this study, we have shown that flt3-ligand (FL), a growth factor that controls early haematopoiesis, regulated the function and expression of the beta-1 integrins, very late antigen (VLA)-4 and VLA-5 on HPC. The modulation of the adhesiveness of HPC by FL was studied by adhesion assays on umbilical vein endothelial cells (HUVEC). Stimulation by FL induced two peaks of increased adhesiveness of HPC. The first peak was at around 30 min and was mechanistically related to an activation of the beta-1 integrins, mainly VLA-4 and VLA-5. The second peak was at around 12 h and was related to increased expression of VLA-4 and VLA-5. The control of HPC adhesiveness by FL is a previously unreported property of FL that may be important for the homing and the retention of flt3-expressing HPC within the bone marrow microenvironment.  相似文献   
95.
A sensitive complement-dependent chromium release cytotoxicity assay was used to determine whether sera from rheumatoid arthritis (RA) patients contain antibody specific for an antigen on rheumatoid synovial cell cultures. Two hundred eight RA sera-RA synovial culture combinations were studied employing 21 sera and 16 synovial membranes; control combinations were derived from 5 normal sera and 10 degenerative joint disease synovial membranes. Anticomplementary activity of some rheumatoid sera was overcome using an increased complement concentration. The percent cytotoxicity of RA serum-RA culture combinations, both homologous and autologous, was not significantly greater than that of RA serum-control culture combinations. No correlation between duration of disease or duration of cell culture and percent cytotoxicity was found. Thus a unique antigen on cultured rheumatoid synovial cells was not recognized by rheumatoid serum antibody by use of this cytotoxicity assay.  相似文献   
96.
This paper reports on the identification and full chemical characterization of isotonitazene (N,N‐diethyl‐2‐[5‐nitro‐2‐({4‐[(propan‐2‐yl)oxy]phenyl}methyl)‐1H‐benzimidazol‐1‐yl]ethan‐1‐amine), a potent NPS opioid and the first member of the benzimidazole class of compounds to be available on online markets. Interestingly, this compound was sold under the name etonitazene, a structural analog. Identification of isotonitazene was performed by gas chromatography mass spectrometry (GC–MS) and liquid chromatography time‐of‐flight mass spectrometry (LC‐QTOF‐MS), the latter identifying an exact‐mass m/z value of 411.2398. All chromatographic data indicated the presence of a single, highly pure compound. Confirmation of the specific benzimidazole regio‐isomer was performed using 1H and 13C NMR spectroscopy, after which the chemical characterization was finalized by recording Fourier‐transform (FT‐IR) spectra. A live cell‐based reporter assay to assess the in vitro biological activity at the μ‐opioid receptor (MOR) revealed that isotonitazene has a high potency (EC50 of 11.1 nM) and efficacy (Emax 180% of that of hydromorphone), thus confirming that this substance is a strong opioid. Isotonitazene has not been previously detected, either in powder form, or in biological fluids. The high potency and efficacy of isotonitazene, combined with the fact that this compound was being sold undiluted, represents an imminent danger to anyone aiming to use this powder.  相似文献   
97.
Background: Chronic kidney disease (CKD) is a renal disorder characterized by the accumulation of uremic toxins with limited strategies to reduce their concentrations. A large amount of data supports the pivotal role of intestinal microbiota in CKD complications and as a major source of uremic toxins production. Here, we explored whether fecal microbiota transplantation (FMT) could be attenuated in metabolic complication and uremic toxin accumulation in mice with CKD. Methods: Kidney failure was chemically induced by a diet containing 0.25% (w/w) of adenine for four weeks. Mice were randomized into three groups: control, CKD and CKD + FMT groups. After four weeks, CKD mice underwent fecal microbiota transplantation (FMT) from healthy mice or phosphate buffered saline as control. The gut microbiota structure, uremic toxins plasmatic concentrations, and metabolic profiles were explored three weeks after transplantation. Results: Associated with the increase of alpha diversity, we observed a noticeable improvement of gut microbiota disturbance, after FMT treatment. FMT further decreased p-cresyl sulfate accumulation and improved glucose tolerance. There was no change in kidney function. Conclusions: These data indicate that FMT limited the accumulation of uremic toxins issued from intestinal cresol pathway by a beneficial effect on gut microbiota diversity. Further studies are needed to investigate the FMT efficiency, the timing and feces amount for the transplantation before, to become a therapeutic option in CKD patients.  相似文献   
98.

Background

Depressive and anxiety disorders (DAD) have become a major public health problem. Multiple trauma is known to increase the risk of DAD through a sensitization mechanism. We investigate the hypothesis that resilience is a mediator of this mechanism.

Methods

Former Hidden Children (FHC), the Jewish youths who spent World War II in various hideaway shelters across Nazi-occupied Europe, were compared with a control group. In each group, we measured the presence of multiple traumas, the resilience with the Resilience Scale for Adults, which has a six factors solution, and the DAD with the Hopkins Symptoms Checklist. We test a mediated moderation model with childhood trauma as the predictor; Later trauma as the moderator; Resilience as the mediator; and DAD as the outcome variable.

Results

Results are consistent with a sensitization model of DAD mediated by resilience: confrontation with a primary trauma during childhood followed by secondary trauma(s) after childhood damages resilience, which, in turn, results in higher level of DAD.

Limitations

We are unable to differentiate if the sensitization process is a consequence of the nature of the trauma endured by FHC (long-standing exposure to extreme external events) or a consequence of the fact that this first trauma occurred during childhood.

Conclusions

Resilience construct is multi-factorial and a limited damaging of some of the factors is sufficient to lead to DAD even if other factors remain unaltered. Resilience can be altered by multiple traumas and, therefore, needs to be bolstered in therapy sessions.  相似文献   
99.
Interactions between interictal epileptiform discharges (IEDs) and distant cortical regions subserve potential effects on cognition of patients with focal epilepsy. We hypothesize that “healthy” brain areas at a distance from the epileptic focus may respond to the interference of IEDs by generating inhibitory alpha and beta oscillations. We predict that more prominent alpha‐beta oscillations can be found in patients with less impaired neurocognitive profile. We performed a source imaging magnetoencephalography study, including 41 focal epilepsy patients: 21 with frontal lobe epilepsy (FLE) and 20 with mesial temporal lobe epilepsy. We investigated the effect of anterior (i.e., frontal and temporal) IEDs on the oscillatory pattern over posterior head regions. We compared cortical oscillations (5–80 Hz) temporally linked to 3,749 IEDs (1,945 frontal and 1,803 temporal) versus an equal number of IED‐free segments. We correlated results from IED triggered oscillations to global neurocognitive performance. Only frontal IEDs triggered alpha‐beta oscillations over posterior head regions. IEDs with higher amplitude triggered alpha‐beta oscillations of higher magnitude. The intensity of posterior head region alpha‐beta oscillations significantly correlated with a better neuropsychological profile. Our study demonstrated that cerebral cortex protects itself from IEDs with generation of inhibitory alpha‐beta oscillations at distant cortical regions. The association of more prominent oscillations with a better cognitive status suggests that this mechanism might play a role in determining the cognitive resilience in patients with FLE.  相似文献   
100.
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