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61.
A patient is described with the bird-egg syndrome who experienced an anaphylactic reaction after eating some of her parrot's food (pine nuts: Pinus pinea ). Specific IgE against this nut and another pine nut ( P cembra ) was demonstrated by RAST. Cross-reactivity between these botanically related seeds was shown by RAST inhibition. Besides avian antigens, bird food antigens should be taken into consideration when symptoms of allergy occur on exposure to birds.  相似文献   
62.
The basic principles of the adhesion of bacteria to polymer surfaces are discussed, as the first important step in the pathogenesis of foreign-body infections. Strategies for the prevention of foreign-body infections by polymer modification with ionizing radiation are presented. These include the modification of polymer surfaces by radiation or glow discharge techniques to obtain antiadhesive or antimicrobial surfaces, as well as the fixation or incorporation of antibiotic drugs to or into the polymer.  相似文献   
63.
This report describes the design, methods and clinical results of a prospective sequential multinational (5 countries) study conducted to evaluate the effects of subcutaneous sumatriptan on health-related quality of life, workplace productivity, clinical parameters and patient satisfaction. Adult patients with moderate to severe migraine initially received customary therapy for migraine episodes for 12 weeks, followed by 24 weeks' treatment with self-administered subcutaneous sumatriptan 6 mg. Demographic, baseline, health-related quality of life and patient satisfaction rating data were collected during visits to the clinic. Data relating to migraine symptoms, migraine therapy, work productivity and non-work activity time were collected on diary cards filled out by the patients. 749 patients were recruited to the study and 637 received at least 1 dose of sumatriptan. Overall, 75.5% of migraines were successfully treated within 2 hours with sumatriptan compared with 31.9% with customary therapy; 36% of patients reported complete relief at 2 hours with sumatriptan treatment compared with 1% of patients receiving customary therapy. 69% of patients successfully treated 70% of their migraines with sumatriptan within 2 hours, compared with 12% of patients with customary therapy. No serious adverse events were reported; 50% of patients reported an adverse event during the 12-week customary therapy phase and 89% of patients during the 24-week sumatriptan phase. These clinical results, which are consistent with those reported in randomised blinded studies of subcutaneous sumatriptan, suggest that relief of migraine symptoms occurs more often, and in less time, in patients receiving subcutaneous sumatriptan rather than customary therapy as their primary medication.  相似文献   
64.
BACKGROUND/AIM: Cholecystokinin (CCK) stimulates secretion and evokes a hyperplastic response in the rat pancreas. The aims of this study were to measure the effect of chronic hyperCCKemia induced by pancreatico-biliary diversion (PBD) on pancreatic enzyme concentrations, on amylase secretion by dispersed acinar cells, and on the CCK-stimulated secretion of pancreatic juice in PBD-operated rats. MATERIAL AND METHODS: Forty-five Sprague-Dawley male rats had either PBD or sham operation 4 weeks before sacrifice or additional experiments. In the first study, 25 rats (13 PBD and 12 sham-operated rats) were either freely fed or fasted overnight before sacrifice. The pancreas was dissected out, weighed and analyzed. In the second study, the rats (6 PBD and 7 sham-operated rats) were fasted overnight before pancreatic acini were prepared. Secretion of amylase during stimulation of acini with CCK-8S and carbachol was measured. In the third study (5 sham-operated and 4 PBD rats), the rats were fasted overnight before basal and CCK-stimulated secretion was measured in vivo. RESULTS: PBD-operated rats showed a threefold increase in pancreatic wet weight with increased contents of DNA, protein and water. The concentration of pancreatic amylase was 7-12% of that found in control animals. The concentrations of trypsin and lipase were also lowered. Stimulation of dispersed pancreatic acini with CCK-8S or carbachol resulted in secretion of amylase to a similar extent in PBD and sham-operated rats. There was no difference in the secretion of pancreatic juice in response to CCK, but although the output of amylase from PBD-operated rats increased with CCK, it remained at a low level throughout the study period. CONCLUSION: PBD evoked hyperplastic changes in the rat pancreas and decreased the concentrations of amylase, trypsin and lipase. However, the capacity of acinar cells to secrete amylase remained intact. The stimulated pancreatic secretion was not changed in volume, but the output of amylase was low in PBD-operated rats. The findings are consistent with the idea that the enlargement of the pancreas following PBD does not improve the secretory capacity.  相似文献   
65.
MR contribution in surgery of epilepsy   总被引:2,自引:0,他引:2  
The contribution of MR imaging in patients with drug-resistant epilepsy considered for surgical therapy is discussed. In this review we focus on: (a) focal abnormalities (mesial temporal sclerosis, focal migration disorders, hamartomatous lesions and low-grade tumours, phakomatosis and vascular malformations) associated with therapy-resistant partial epilepsy, requiring resective surgery; (b) abnormalities leading to generalized seizures that require more drastic surgical procedures, such as callosotomy and functional hemispherectomy; and (c) localisation of implanted depth-electrodes. Received: 6 April 1998; Revision received: 2 June 1998; Accepted: 3 June 1998  相似文献   
66.
Axonal degeneration plays an important role in the accumulation of disability in patients with multiple sclerosis (MS). Pathological studies have demonstrated axonal damage, particularly in areas of acute inflammation and demyelination, and in chronic lesions. Axonal loss and its progression, which is associated with neurological disability, has also been demonstrated by magnetic resonance imaging (MRI) studies. The mechanisms of axonal loss are uncertain, but may involve axonal degeneration secondary to demyelination, or damage to the axonal cytoskeleton. Inflammatory mediators, including cytokines and proteolytic enzymes may contribute to axonal damage, as may nitric oxide. Axonal destruction may also be due to immune attack directed at axonal components. The realisation that axonal degeneration is a fundamental component of MS that may occur early in the disease course should alter the approach to management and open avenues to a more targeted immunotherapy aimed at reducing the progression of disability.  相似文献   
67.
STUDY DESIGN: Biomechanical study using a programmable testing apparatus that replicated physiologic flexion-extension cervical spine motion, and loading mechanics. OBJECTIVES: To determine the influence of anterior, posterior, or combined plating on multilevel cervical strut-graft mechanics in vitro. SUMMARY OF BACKGROUND DATA: The addition of instrumentation does not prevent construct failure in multilevel (more than two levels) cervical corpectomy. METHODS: Six fresh human cadaveric cervical spines (C2-T1) were tested in six sequential conditions that included harvested (H), C4-6 corpectomy, strut grafted, strut grafted with an anterior cervical plate (SGAP), strut grafted with posterior plates (SGPP), and strut grafted with combined anterior and posterior plates (SGAPP). A customized force-sensing strut graft (FSSG) was used to measure axial compression-tension, flexion-extension and lateral bending moments, and axial torsion. Parameters of stiffness, segmental vertebral motion, and strut-graft loads were compared, to determine differences among the spine conditions. RESULTS: Flexion of the strut-grafted spine loaded the FSSG, and extension motion unloaded the FSSG. With the anterior plate, flexion of the SGAP spine significantly unloaded the FSSG; extension loaded the FSSG more than flexion of the unplated spine (P = 0.03). The opposite occurred with the posterior plates (SGPP), where flexion of the spine significantly loaded the FSSG (more than the strut grafted spine) and extension unloaded the FSSG (P < 0.03). The combined construct (SGAPP) counteracted the tension band effect of the individual plates and demonstrated significantly less overall FSSG load change than either plate alone (P = 0.03). CONCLUSIONS: Multilevel cervical instrumentation effectively increases stiffness after corpectomy. However, anterior or posterior plating alone excessively loads the graft with small degrees of motion, which may promote pistoning and failure of multilevel constructs.  相似文献   
68.
The present study examined whether the measurement of swallowing activity by electromyography (EMG) provides a sensitive and valid method for the assessment of the amount of saliva secreted. Thirteen subjects tasted lemon juice and water, and smelled lasagna and hay, while the amount of saliva, measured with the aid of cotton dental rolls, was compared with the number of peaks in the EMG activity of the musculus digastricus. Swallowing indeed differentiated between the stimuli and the correlation between the number of swallows and the amount of saliva was significant. The present data suggest that monitoring the swallowing movement using EMG might be a sensitive, valid and reliable method for the measurement of salivary flow. The use is recommended for the measurement of salivation when a simple and non-invasive method is needed.  相似文献   
69.
OBJECTIVE: Although self-esteem and overconcern with body shape and weight are considered to be closely connected in bulimia nervosa, little empirical research has been done to investigate the alleged link. METHOD: In this study, we examined experimentally whether overconcern with body shape and weight was connected with self-esteem in an analogue sample of high restrained eaters by means of a subliminal lexical decision task. RESULTS: It could indeed be demonstrated that low self-esteem and overconcern with body shape and weight are associated in high restrained eaters: after priming low self-esteem, the accessibility of subliminally presented body shape and weight stimuli was increased. The effect was not found with a supraliminal lexical decision task. DISCUSSION: Apparently, the automatic, nonconscious processing of body shape and weight words was influenced in high restrained eaters with a low state self-esteem, whereas the strategic, conscious processing was not. As soon as the body shape and weight stimuli were processed consciously, the initial increased accessibility was countered and the effect disappeared.  相似文献   
70.
The present study was performed to investigate the ability of the multidrug resistance protein (MRPI) to transport different cationic substrates in comparison with MDR1-P-glycoprotein (MDR1). Transport studies were performed with isolated membrane vesicles from in vitro selected multidrug resistant cell lines overexpressing MDR1 (A2780AD) or MRP1 (GLC4/Adr) and a MRP1-transfected cell line (S1(MRP)). As substrates we used 3H-labelled derivatives of the hydrophilic monoquaternary cation N-(4',4'-azo-in-pentyl)-21-deoxy-ajmalinium (APDA), the basic drug vincristine and the more hydrophobic basic drug daunorubicin. All three are known MDR1-substrates. MRP1 did not mediate transport of these substrates per se. In the presence of reduced glutathione (GSH), there was an ATP-dependent uptake of vincristine and daunorubicin, but not of APDA, into GLC4/Adr and S1(MRP) membrane vesicles which could be inhibited by the MRP1-inhibitor MK571. ATP- and GSH-dependent transport of daunorubicin and vincristine into GLC4/Adr membrane vesicles was inhibited by the MRP1-specific monoclonal antibody QCRL-3. MRP1-mediated daunorubicin transport rates were dependent on the concentration of GSH and were maximal at concentrations > or = 10 mM. The apparent KM value for GSH was 2.7 mM. Transport of daunorubicin in the presence of 10 mM GSH was inhibited by MK571 with an IC50 of 0.4 microM. In conclusion, these results demonstrate that MRP1 transports vincristine and daunorubicin in an ATP- and GSH-dependent manner. APDA is not a substrate for MRP1.  相似文献   
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