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991.
PURPOSE: To report the efficacy of primary retrobulbar chlorpromazine injections for the management of blind and seeing painful eyes. PATIENTS AND METHODS: Retrospective case series from three university hospitals was done. Twenty eyes of 20 patients with at least 3 months of follow-up are reported. Ten of these 20 eyes did not receive any other ophthalmic medications either 2 weeks before chlorpromazine injection or at any time point after injection. Treatment was considered successful if pain control lasted for at least 3 months, without the need for reinjection or enucleation. RESULTS: Sixteen of 20 (80.0%) eyes achieved successful pain control. There were no permanent complications in any patient. CONCLUSIONS: Retrobulbar chlorpromazine appears to be safe and effective for the management of pain in blind eyes.  相似文献   
992.
BACKGROUND: The Directive 1999/0244 (COD), recently approved by the European Parliament, proposed that the content and presentation of health warnings on cigarette packets be modified. The aim of the present study was to analyse the potential effect of the planned measures on the perceptions by Spanish youth of the risks associated with smoking. METHOD: A sample of 435 students attending the University of La Rioja were surveyed on their perceptions of the principal health risks attributable to the consumption of tobacco i.e. lung cancer, respiratory diseases and cardiovascular disease. A questionnaire was administered before and after they were presented with a demonstration of the health warnings on cigarette packets based on the new European Union directive. RESULTS: Perceptions changed significantly following exposure to the content and type of information of the new packaging. In general, the university students attributed a higher health risk to smoking following the presentation. CONCLUSIONS: The measures developed by the public sector to present a higher profile of anti-tobacco health warnings do influence the target population in the desired direction, at least in the short term. Hence, given that the perception of risk influences the election to smoke, it is predictable that when these types of policy decisions are applied, there will be a tendency towards a reduction in the incidence and prevalence of tobacco consumption.  相似文献   
993.
Regulation of p53: intricate loops and delicate balances   总被引:7,自引:0,他引:7  
The p53 tumor suppressor protein provides a major anti-cancer defense mechanism, as underscored by the fact that the p53 gene is the most frequent target for genetic alterations in human cancer. Recent work has led to the realization that p53 lies at the hub of a very complex network of signaling pathways, which integrate a variety of intracellular and extracellular inputs. Part of this network consists of an array of autoregulatory feedback loops, where p53 exhibits very intricate interactions with other proteins known to play important roles in the determination of cell fate. We discuss two such loops, one involving the beta catenin protein and the other centering on the Akt/protein kinase B. In both cases, the central module is the interplay between p53 and the murine double minute 2 (Mdm2) protein, which inactivates p53 and targets it for rapid proteolysis. Whereas deregulated beta catenin can lead to Mdm2 inactivation and p53 accumulation, active p53 can promote the degradation and downregulation of beta catenin. Similarly, Akt can block p53 activation by potentiating Mdm2, whereas activated p53 can tune down Akt in several different ways. In each case, the actual output of the loop is determined by the delicate balance between the opposing effects of its different components. Often, this balance is dictated by additional signaling processes that occur simultaneously within the same cell. Genetic alterations characteristic of cancer are capable of severely distorting this balance, thereby overriding the tumor suppressor effects of p53 in a manner that facilitates neoplastic conversion.  相似文献   
994.
The endogenous cannabinoid, anandamide, has been shown to attenuate naloxone-precipitated opiate withdrawal in rodents. Here we show that the spontaneous, but not the naloxone-precipitated withdrawal syndrome in morphine-dependent mice is attenuated by the inhibitor of carrier-mediated anandamide transport N-(4-hydroxyphenyl) arachidonylethanolamide (AM404) (2 and 10 mg/kg, i.p.). These results suggest that spontaneous but not opioid antagonist-precipitated withdrawal is associated with dynamic changes in endogenous cannabinoid signaling.  相似文献   
995.
The methods that have been used to estimate the clinical and economic impact of vaccination programmes are not always uniform, which makes it difficult to compare results between economic analyses. Furthermore, the relative efficiency of vaccination programmes can be sensitive to some of the more controversial aspects covered by general guidelines for the economic evaluation of healthcare programmes, such as discounting of health gains and the treatment of future unrelated costs. In view of this, we interpret some aspects of these guidelines with respect to vaccination and offer recommendations for future analyses. These recommendations include more transparency and validation, more careful choice of models (tailored to the infection and the target groups), more extensive sensitivity analyses, and for all economic evaluations (also nonvaccine related) to be in better accordance with general guidelines. We use these recommendations to interpret the evidence provided by economic evaluation applied to viral hepatitis vaccination. We conclude that universal hepatitis B vaccination (of neonates, infants or adolescents) seems to be the most optimal strategy worldwide, except in the few areas of very low endemicity, where the evidence to enable a choice between selective and universal vaccination remains inconclusive. While targeted hepatitis A vaccination seems economically unattractive, universal hepatitis A vaccination strategies have not yet been sufficiently investigated to draw general conclusions.  相似文献   
996.
Trying to define the precise role played by insulin regulating the survival of brown adipocytes, we have used rat fetal brown adipocytes maintained in primary culture. The effect of insulin on apoptosis and the mechanisms involved were assessed. Different from the known effects of insulin as a survival factor, we have found that long-term treatment (72 h) with insulin induces apoptosis in rat fetal brown adipocytes. This process is dependent on the phosphatidylinositol 3-kinase/mammalian target of rapamycin/p70 S6 kinase pathway. Short-term treatment with the conditioned medium from brown adipocytes treated with insulin for 72 h mimicked the apoptotic effect of insulin. During the process, caspase 8 activation, Bid cleavage, cytochrome c release, and activation of caspases 9 and 3 are sequentially produced. Treatment with the caspase inhibitor, benzyloxycarbonyl-Val-Ala-Asp (Z-VAD), prevents activation of this apoptotic cascade. The antioxidants, ascorbic acid and superoxide dismutase, also impair this process of apoptosis. Moreover, generation of reactive oxygen species (ROS), probably through reduced nicotinamide adenine dinucleotide phosphate oxidases, and a late decrease in reduced glutathione content are produced. According to this, antioxidants prevent caspase 8 activation and Bid cleavage, suggesting that ROS production is an important event mediating this process of apoptosis. However, the participation of uncoupling protein-1, -2, and -3 regulating ROS is unclear because their levels remain unchanged upon insulin treatment for 72 h. Our data suggest that the prolonged hyperinsulinemia might cause insulin resistance through the loss of brown adipose tissue.  相似文献   
997.
Recent studies on the mechanisms of arsenite toxicity report that some of its effects have been traced to the generation of reactive oxygen species during oxidative stress. In this study we analyze the formation of hydroxyl radicals in the brain of awake, freely moving rats, in order to obtain direct evidence of arsenic-induced oxidative stress in this tissue. We examined the time-course of hydroxyl radical formation in the striatum of both female and male rats who underwent a direct infusion during 60 min of different concentrations of arsenite in that structure through a microdialysis probe. We report here that basal levels of hydroxyl radical production in female rats are significantly higher than those in male rats (91.9+/-16.1 vs. 59.2+/-18.1 pmol/ml, P<0.001) and that the treatment with arsenite induced significant increases of hydroxyl radical formation over basal levels at 50, 100, 200 and 400 microM (95, 98, 98 and 99% increases, respectively, P<0.05 in all cases). The maximal response to 100 microM arsenite is significantly higher in female than in male rats (194.6+/-50.1 female rats and 88.1+/-11.6 pmol/ml male rats, P=0.036). These results support the participation of hydroxyl radicals in arsenic-induced disturbances in the central nervous system.  相似文献   
998.
We have evaluated changes in the expression of neurotrophin-3 (NT-3) and its tyrosine kinase C (TrkC) receptor in the neuromuscular system as a result of voluntary physical activity. We assessed changes in the mRNAs and proteins for NT-3 and TrkC in the lumbar spinal cord and associated soleus muscle following 3 and 7 days of voluntary wheel running. We used quantitative Taqman RT-PCR to measure mRNA and ELISA to assess protein levels. NT-3 mRNA and protein levels increased in the spinal cord to reach statistical significance after 7 days of exercise compared to sedentary control rats. Immunohistochemical analyses localized the elevated NT-3 to the substantia gelatinosa (SG) and nucleus of the dorsal horn. TrkC mRNA levels were significantly elevated in the spinal cord after 3 and 7 days of running. In the soleus muscle, NT-3 mRNA levels and its receptor TrkC were elevated after 3 days, while NT-3 protein levels remained unaffected. The results demonstrate that voluntary exercise has a differential effect on NT-3 as well as its receptor TrkC in the neural and muscular components of the neuromuscular system, and emphasize the role of voluntary activity on the spinal cord and muscle.  相似文献   
999.
PURPOSE: To describe postoperative outcome in patients with familial mesial temporal lobe epilepsy (FMTLE). METHODS: We studied FMTLE patients who underwent surgical treatment for refractory seizures. FMTLE was defined when at least two individuals in a family had a clinical EEG diagnosis of MTLE. Preoperative investigation included magnetic resonance imaging (MRI), interictal/ictal EEGs, and neuropsychological evaluation. We used Engel's classification for postoperative outcome. RESULTS: To date, 20 FMTLE patients have been operated on, with 1.6 to 9.8 years of follow-up (mean, 5.5 years). Hippocampal atrophy (HA) and other signs of mesial temporal sclerosis (MTS) were present in 18 patients (15 unilateral). Seizures were recorded in 19 patients. Seventeen (85%) patients are in class I. Two patients had normal hippocampal volumes (HcV): one (5%) is in class II and the other (5%) in class IV (extratemporal seizures developed after surgery). One (5%) patient had bilateral HA and is in class III. Qualitative histopathology showed MTS with different degrees of severity. CONCLUSIONS: Refractory FMTLE patients have good surgical outcome when unilateral or clearly asymmetric HA is identified. Preoperative investigation should be the same as that in patients with sporadic refractory MTLE.  相似文献   
1000.
Spinal cord MRI in clinically isolated optic neuritis   总被引:4,自引:0,他引:4  
BACKGROUND/METHODS: One hundred and fifteen patients with clinically isolated optic neuritis underwent magnetic resonance imaging (MRI) of the brain and spinal cord within 3 months of the onset of symptoms. RESULTS: Eighty one (70%) patients had brain lesions and 31 (27%) had cord lesions. Cord lesions were seen in 12% with a normal brain MRI, 21% with between one and eight brain lesions, and 45% with nine or more brain lesions. When the new diagnostic criteria for MS were applied, MRI cord imaging used for evidence of dissemination in time and space allowed a diagnosis of MS in only one additional asymptomatic patient at 1 year, two additional asymptomatic patients at 3 years. CONCLUSIONS: Using existing criteria, spinal cord imaging rarely contributes to the diagnosis in patients with clinically isolated optic neuritis.  相似文献   
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