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71.
Abstract: Pigmented fungiform papillae of the tongue is a benign condition characterized by localized hyperpigmentation confined to fungiform papillae. Although the condition is not rare and might be easily diagnosed in dark‐skinned adults and children, it is seldom mentioned in the medical literature. Here, we describe an 11‐year‐old boy presenting typical features of pigmented fungiform papillae of the tongue.  相似文献   
72.
Letters to the Editor are welcomed for publication (subject to editing). Letters must be signed by all authors, and must not exceed two pages of text including references. Letters should not duplicate material submitted or published in other journals. Prepublication proofs will not be provided.  相似文献   
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74.
Aim: To evaluate whether the ventricular septal defect (VSD) size, along with the degree of preoperative growth impairment and age at repair, may influence postoperative growth, and if VSD size can be useful to identify children at risk for preoperative failure to thrive. Methods: Sixty‐eight children submitted to VSD repair in a Brazilian tertiary‐care institution were evaluated. Weight and height measurements were converted to Z‐scores. Ventricular septal defect size was normalized by dividing it by the aortic root diameter (VSD/Ao ratio). Results: Twenty‐six patients (38%) had significantly low weight‐for‐height, 10 patients (15%) had significantly low height‐for‐age and 13 patients (19%) had both conditions at repair. Catch‐up growth occurred in 82% of patients for weight‐for‐age, in 75% of patients for height‐for‐age and in 89% of patients for weight‐for‐height. Weight‐for‐height Z‐scores at surgery were significantly lower in patients who underwent repair before 9 months of age. The VSD/Ao ratio did not associate with any other data. On multivariate analysis, weight‐for‐age Z‐scores and age at surgery were independent predictors of long‐term weight and height respectively. Conclusion: The VSD/Ao ratio was not a good predictor of preoperative failure to thrive. Most patients had preoperative growth impairment and presented catch‐up growth after repair. Preoperative growth status and age at surgery influenced long‐term growth.  相似文献   
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76.
A large-scale review of the literature concerning the effects of noise on hearing, published primarily during the 1970s, was initiated by the National Institute of Neurological and Communicative Disorders and Stroke in 1981. This review demonstrated a continuing search for medicinal treatment for the adverse effects of noise on hearing. The present article focuses on the results of investigations of human subjects. The literature in this area is primarily European and deals principally with treatment of acoustic trauma, although a few reports have described attempts to render the ear less susceptible to the hazards of chronic noise exposure. Much of the published information is of questionable value because of inadequate experimental design and control. To date, the search for effective medicinal treatment for hearing loss caused by noise has been unsuccessful. Results reported from studies of the effects of carbogen are encouraging and suggest that continued rigorous investigation of this agent is warranted.  相似文献   
77.
Laryngeal aerodynamics associated with selected voice disorders   总被引:1,自引:0,他引:1  
Measures of estimated subglottal air pressure and laryngeal air flow during speech production are compared for adults with normal laryngeal function and those with laryngeal abnormalities. The most traditional measure, air flow during sustained vowel production, is not a strong predictor of laryngeal function during speech production. Subglottal air pressure and laryngeal air flow offer insight into voice disorders and provide directions for therapy as well as a method for the quantitative assessment of treatment outcomes.  相似文献   
78.
Head and neck squamous cell carcinoma (HNSCC) is characterized by its capacity to invade adjacent tissues and to metastasize locoregionally. Evidence suggests that matrix metalloproteinases (MMPs) may play a causal role in HNSCC progression. While evaluating the role of MMPs in the invasion process, we made the surprising observation that a broad-spectrum MMP inhibitor, (marimastat, BB2516), inhibited the growth in vitro of some HNSCC cell lines. This inhibitory effect was only found in HNSCC cell lines overexpressing epidermal growth factor receptors. The effects of the MMP inhibitor could be reversed by adding exogenous c-erbB ligands, suggesting that the phenomenon may be related to autocrine ligand processing. This hypothesis was supported by the finding that the growth-inhibitory effect of marimastat was directly related to its ability to prevent the release of major c-erbB ligands including transforming growth factor-alpha, betacellulin and heregulin beta1 from HNSCC. Marimastat was also found to potentiate the cytotoxic effects of cisplatin both in vitro and in vivo. Our results indicate that the cleavage of several c-erbB ligands from membrane-anchored precursors requires MMP activity. We conclude that MMP inhibitors could prevent tumor progression not only by inhibiting invasion and angiogenesis, as previously shown, but also by their ability to inhibit autocrine signaling through the c-erbB receptors. Clinical trials to test this hypothesis in HNSCC should be considered.  相似文献   
79.
Objective : To determine the prevalence and perinatal predictors of cerebral palsy, intellectual impairment, visual impairment and deafness in a cohort of extremely low birthweight (ELBW) infants at two years of age.
Methodology : The study population comprised 199 of the 224 (89%) ELBW infants managed at the Mater's Mothers Hospital, Brisbane, between July 1977 and February 1990 and who survived to two years. The prevalence of cerebral palsy, intellectual impairment, blindness and deafness was measured by clinical, psychometric and audiological assessment and the association with 24 risk factors examined.
Results : Cerebral palsy occurred in 20 children (10%). Risk of cerebral palsy was associated with ventricular dilatation, intraventricular haemorrhage, necrotizing enterocolitis and multiple birth, though only ventricular dilatation (OR 4.41; 95% Cl 1.32-14.8) remained significant in the adjusted analysis. Intellectual impairment occurred in 20 children (10%) and was independently associated with ventricular dilatation (OR 15.0; 95% Cl 2.2-102.8), ventilation F iO2 >80% (OR 3.4; 95% Cl 1.01-11.5), vaginal delivery (OR 3.5; 95% Cl 1.09-11.4) and male sex (OR 6.1; 95% Cl 1.67-22.3). No perinatal predictor was statistically associated with risk of deafness. Retinopathy of prematurity (OR 36.9; 95% Cl 2.8-495.5) was associated with risk of later visual impairment.
Conclusions : Intellectual impairment was associated with a broad range of perinatal variables. Cerebral palsy was associated with fewer variables, all of which were also associated with intellectual impairment. Neurologic injury was associated with male sex and multiple birth, which are not biological insults themselves, but may be markers of susceptibility to injury.  相似文献   
80.
This paper explores the role of milk-based formulae in achieving four aspects of nutritional health in infants and toddlers: in the suckling, to mimic the amino acid metabolism and the faecal flora of a breast-fed baby; in the weanling, to achieve adequate protein intakes in later infancy and beyond and to achieve satisfactory haemoglobin concentrations in the early toddler years. Milk-based formulae have two roles in infant nutrition: as so-called breast milk substitutes and as a safety net during the weaning period; the latter role may be the more important.  相似文献   
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