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991.
The purpose of this study was to survey the frequency of denture-related lesions of the oral mucosa in patients treated at a Brazilian dental school and to determine if the oral lesions were related to age, sex, denture type, length of denture use and denture cleaning methods. The denture-related lesions observed in this study were chronic atrophic candidiasis, chronic hyperplastic candidiasis, denture-induced fibrous inflammatory hyperplasia (FIH), traumatic ulcer, angular cheilitis and flabby ridge. The most frequent lesion, chronic atrophic candidiasis, occurred more frequently in females, in complete maxillary denture wearers, with denture use for 16-20 years. The most common method of cleaning dentures was a toothbrush and toothpaste. These results suggest that dentures can cause a wide range of lesions of the oral mucosa, that could be prevented with follow-up to evaluate dentures and provide instructions on how to maintain oral tissues healthy.  相似文献   
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The synthesis of two new families of compounds with oxadiazoline and quinazolinone structures and their in vitro biological evaluation as inhibitors of both neuronal and inducible nitric oxide synthases (nNOS and iNOS) are described. These derivatives have been obtained from cyclization of substituted benzohydrazides with acid anhydrides followed by reduction, using different synthetic procedures. Their structures were confirmed by high-resolution mass spectroscopy and 1H and 13C nuclear magnetic resonance data. In general, the assayed compounds show better inhibition values of nNOS than of iNOS, being 7d the most active derivative with a quinazolinone scaffold, and 6t the best oxadiazoline one and the best nNOS inhibitor of all tested compounds. The structure–activity relationships are discussed in terms of the effects of the substituents on both 2- and 3-positions of the heterocyclic rings.  相似文献   
994.
Purpose: To report the newest ophthalmic manifestations of a mother-daughter pair diagnosed with toe syndactyly, telecanthus, anogenital and renal malformations (STAR) syndrome, a rare X-linked developmental disorder.

Methods: The medical and ophthalmic records were reviewed for a mother-daughter pair diagnosed with FAM58A confirmed STAR syndrome on chromosome Xq28.

Results: The mother at birth had left foot syndactyly, telecanthus, anal stenosis, and clitoromegaly and was told at 19 she had a hypoplastic left kidney. The daughter, born at 38 weeks after a complication of oligohydramnios, had a more severe presentation, demonstrating toe syndactyly, telecanthus, anal stenosis, clitoromegaly, bilateral renal hypoplasia, ureteral reflux, urogenital sinus, and congenital heart disease amongst others. The pair shared similar ophthalmic findings, though those of the daughter were more pronounced. They included bilateral, medial upper eyelid prominences with madarosis, mild peripapillary atrophy, and soft macular drusen with the daughter also displaying optic nerve hypoplasia and peripheral anterior synechia in the iridocorneal angle.

Conclusion: These ophthalmic findings are the first reported to our knowledge in association with STAR syndrome. The literature frequently demonstrates that patients with developmental anomalies often have ocular manifestations, warranting a full ophthalmic examination when the diagnosis of STAR syndrome has been made or is being considered.  相似文献   

995.
Aim To compare the efficacy of topiramate with naltrexone in the treatment of alcohol dependence. Design The investigation was a double‐blind, placebo‐controlled, 12‐week study carried out at the University of São Paulo, Brazil. Sample A total of 155 patients, 18–60 years of age, with an International Classification of Diseases (ICD‐10) diagnosis of alcohol dependence. Methods After a 1‐week detoxification period, patients were assigned randomly to receive topiramate (induction to 300 mg/day), naltrexone (50 mg/day) or placebo. Measurements Time to first relapse (consumption of >60 g ethyl alcohol), cumulative abstinence duration and weeks of heavy drinking. Findings In intention‐to‐treat analyses, topiramate was statistically superior to placebo on a number of measures including time to first relapse (7.8 versus 5.0 weeks), cumulative abstinence duration (8.2 versus 5.6 weeks), weeks of heavy drinking (3.4 versus 5.9) and percentage of subjects abstinent at 4 weeks (67.3 versus 42.6) and 8 weeks (61.5 versus 31.5), but not 12 weeks (46.2 versus 27.8). Results remained significant after controlling for Alcoholics Anonymous attendance, which was higher in topiramate than in other groups. There were no significant differences between naltrexone versus placebo or naltrexone versus topiramate groups, but naltrexone showed trends toward inferior outcomes when compared to topiramate. Conclusions The results of this study support the efficacy of topiramate in the relapse prevention of alcoholism. Suggestive evidence was also obtained for superiority of topiramate versus naltrexone, but this needs to be verified in future research with larger sample sizes.  相似文献   
996.
Brain levels of adenosine are elevated during hypoxia. Through effects on adenosine receptors (A(1), A(2A), A(2B) and A(3)) on astrocytes, adenosine can influence functions such as glutamate uptake, reactive gliosis, swelling, as well as release of neurotrophic and neurotoxic factors having an impact on the outcome of metabolic stress. We have studied the roles of these receptors in astrocytes by evaluating their susceptibility to damage induced by oxygen deprivation or exposure to the hypoxia mimic cobalt chloride (CoCl(2)). Hypoxia caused ATP breakdown and purine release, whereas CoCl(2) (0.8 mM) mainly reduced ATP by causing cell death in human D384 astrocytoma cells. Further experiments were conducted in primary astrocytes prepared from specific adenosine receptor knock-out (KO) and wild type (WT) mice. In WT cells purine release following CoCl(2) exposure was mainly due to nucleotide release, whereas hypoxia-induced intracellular ATP breakdown followed by nucleoside efflux. N-ethylcarboxamidoadenosine (NECA), an unselective adenosine receptor agonist, protected from cell death following hypoxia. Cytotoxicity was more pronounced in A(1)R KO astrocytes and tended to be higher in WT cells in the presence of the A(1) receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX). Genetic deletion of A(2A) receptor resulted in less prominent effects. A(3)R KO glial cells were more affected by hypoxia than WT cells. Accordingly, the A(3) receptor agonist 2-chloro-N(6)-(3-iodobenzyl)-N-methyl-5'-carbamoyladenosine (CL-IB-MECA) reduced ATP depletion caused by hypoxic conditions. It also reduced apoptosis in human astroglioma D384 cells after oxygen deprivation. In conclusion, the data point to a cytoprotective role of adenosine mediated by both A(1) and A(3) receptors in primary mouse astrocytes.  相似文献   
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Background

Obsessive Compulsive Disorder (OCD) is a chronic and disabling disorder with poor response to pharmacological treatments. Converging evidences suggest that OCD patients suffer from dysfunction of the cortico-striato-thalamo-cortical (CSTC) circuit, including in the medial prefrontal cortex (mPFC) and the anterior cingulate cortex (ACC).

Objective

To examine whether modulation of mPFC-ACC activity by deep transcranial magnetic stimulation (DTMS) affects OCD symptoms.

Methods

Treatment resistant OCD participants were treated with either high-frequency (HF; 20 Hz), low-frequency (LF; 1 Hz), or sham DTMS of the mPFC and ACC for five weeks, in a double-blinded manner. All treatments were administered following symptoms provocation, and EEG measurements during a Stroop task were acquired to examine changes in error-related activity. Clinical response to treatment was determined using the Yale-Brown-Obsessive-Compulsive Scale (YBOCS).

Results

Interim analysis revealed that YBOCS scores were significantly improved following HF (n = 7), but not LF stimulation (n = 8), compared to sham (n = 8), and thus recruitment for the LF group was terminated. Following completion of the study, the response rate in the HF group (n = 18) was significantly higher than that of the sham group (n = 15) for at least one month following the end of the treatment. Notably, the clinical response in the HF group correlated with increased Error Related Negativity (ERN) in the Stroop task, an electrophysiological component that is attributed to ACC activity.

Conclusion

HF DTMS over the mPFC-ACC alleviates OCD symptoms and may be used as a novel therapeutic intervention. Notwithstanding alternative explanations, this may stem from DTMS ability to directly modify ACC activity.  相似文献   
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