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101.
Despite the advent of improved pharmacological treatments to alleviate substance-related desires, psychological approaches will continue to be required. However, the current psychological treatment that most specifically focuses on desires and their management--cue exposure (CE)--has not lived up to its original promise. This paper argues that current psychological approaches to desire do not adequately incorporate our knowledge about the factors that trigger, maintain, and terminate episodes of desire. It asserts that the instigation and maintenance of desires involve both associative and elaborative processes. Understanding the processes triggering the initiation of intrusive thoughts may assist in preventing some episodes, but occasional intrusions will be inevitable. A demonstration of the ineffectiveness of thought suppression may discourage its use as a coping strategy for desire-related intrusions, and mindfulness meditation plus cognitive therapy may help in accepting their occurrence and letting them go. Competing tasks may be used to reduce elaboration of desires, and competing sensory images may have particular utility. The application of these procedures during episodes that are elicited in the clinic may allow the acquisition of more effective strategies to address desires in the natural environment.  相似文献   
102.
PURPOSE: To investigate the relationship between percentage of body fat and macular pigment (MP) optical density. METHODS: One hundred healthy subjects of ages between 22 and 60 years volunteered to participate in this study. MP optical density was measured psychophysically, serum lutein and zeaxanthin were quantified by HPLC, and dietary intake of lutein and zeaxanthin was assessed using a validated food frequency questionnaire. Body fat was measured by dual energy x-ray absorptiometry (DEXA); body mass index (BMI) was also calculated for each subject. Clinical and personal details were recorded, with particular attention directed toward putative risk factors for AMD. RESULTS: There was a significant inverse relationship between the percentage of body fat and MP optical density in males (r=-0.392, P <0.01), and after correcting for age and dietary lutein and zeaxanthin, this inverse relationship remained significant (r=-0.290, P <0.05). The relationship between MP optical density and percentage of body fat in females was inverse, but not significant (r=-0.197, P=0.149). A significant and inverse relationship between serum zeaxanthin and percentage of body fat was observed for females only (r=-0.354, P <0.01). Dietary intake of fat was inversely related to serum lutein and zeaxanthin, and significantly so for lutein (r=-0.256, P <0.05). However, dietary fat was unrelated to MP optical density (r=0.041, P=0.688). CONCLUSIONS: A relative lack of MP is associated with adiposity in men, and may underlie the association between body fat and risk for AMD progression in males. Further, the processes governing accumulation and/or stabilization of lutein and zeaxanthin in fat tissue appear to differ for males and females.  相似文献   
103.
We present the imaging appearances of a lytic pseudotumor in the right sacral ala presenting with referred pain to the right thigh. Subsequent imaging revealed the presence of a cystic lesion arising at the site of previous bone graft harvest; CT-guided aspiration yielded synovial fluid presumed to arise from the contiguous sacroiliac joint.  相似文献   
104.
PURPOSE: The use of partial breast brachytherapy (PBB) after lumpectomy for selected patients with early-stage breast cancer reduces the adjuvant radiotherapy treatment time to <1 week. Despite the advantages of accelerated treatment, maintaining an acceptable cosmetic outcome is important. In a cohort of patients who received low-dose-rate (LDR) or high-dose-rate (HDR) PBB after lumpectomy, the clinical characteristics and treatment parameters were analyzed to identify predictors for an unfavorable cosmetic outcome. METHODS AND MATERIALS: Early-stage breast cancer patients with clear resection margins and 0-3 positive lymph nodes were eligible for PBB. Uniform guidelines for target definition and brachytherapy catheter placement were applied. The HDR PBB dose was 34 Gy in 10 fractions within 5 days, and the LDR dose was 45 Gy given at a rate of 50 cGy/h. The end points included incidence of radiation recall reaction, telangiectasias, and cosmetic-altering fibrosis. RESULTS: Between 1995 and 2000, 44 patients with early-stage breast cancer received PBB without adjuvant external beam radiotherapy after lumpectomy (31 HDR PBB, 13 LDR PBB). After a median follow-up of 42 months (range 18-86), all patients remained locally controlled. The overall rate of good/excellent cosmetic outcome was 79.6% overall and 90% with HDR PBB. Radiation recall reactions occurred in 43% of patients (6 of 14) who received adriamycin. LDR PBB and adriamycin were significant predictors for late unfavorable cosmetic changes in univariate analysis (p = 0.003 and p = 0.005, respectively). CONCLUSION: Although a high rate of local control and good/excellent cosmetic outcome is provided with HDR PBB, the risk of unfavorable cosmetic changes when treated with both LDR PBB and adriamycin is noteworthy. This suggests that HDR PBB is preferred in patients for whom adriamycin is indicated.  相似文献   
105.
Pulmonary aspergillosis: clinical presentation, diagnosis and therapy   总被引:5,自引:0,他引:5  
Pulmonary aspergillosis is a serious threat to those immunocompromised as a result of disease or therapy, and has been identified as a major cause of morbidity and mortality in asthmatic and cystic fibrosis patients. Pulmonary aspergillosis can occur in three principal forms: saprophytic, allergic and invasive. Saprophytic aspergillosis involves colonisation of the airways, without invasion or damage of viable tissue, and may present as an aspergilloma (fungus ball) consisting of a tangled mass of mycelium, fibrin, inflammatory cells and epithelial-cell debris. Necrotic tissue also may be invaded but usually only in those severely immunocompromised. Allergic aspergillosis is referred to frequently as allergic bronchopulmonary aspergillosis (ABPA), and may occur in approximately 25% of asthmatic and 10% of cystic fibrosis patients. ABPA presents as a non-infectious, potentially fatal inflammatory disease where antigens released by the fungal mycelium provoke an immune response. Invasive aspergillosis is probably the most serious form of the disease and involves the invasion of viable tissue. It occurs predominantly in patients with pre-existing lung damage, and can spread to other organs and distant sites in the body. Aspergillomas may be detected on chest X-ray as spherical-shaped objects, whilst allergic aspergillosis may be visualised by radiological techniques and computed tomography (CT) scan. Surgery may be employed in the case of aspergilloma, and chemotherapy relies upon the use of amphotericin B (liposomal and aerosolised) and itraconazole.  相似文献   
106.
AIM: The aim of the study was to determine whether the clinical benefits of galantamine for patients with Alzheimer's disease lead to benefits for caregivers. METHODS: Data were pooled from two concurrent, multi-centre, randomized, double-blind, placebo-controlled, 6-month trials. Time caregivers spent assisting with activities of daily living (ADL) and time patients could be left unsupervised each day were assessed using the Allocation of Caregiver Time Survey. In total, 825 patients with mild-to-moderate Alzheimer's disease were included. RESULTS: At endpoint, caregivers of galantamine-treated patients were more likely to report reductions (41% vs 37%), maintenance (19% vs 14%) or smaller increases (26% vs 34% reporting an increase >30 minutes) in time assisting with ADL compared with the placebo group (p=0.026; Wilcoxon rank-sum test). The mean daily time difference was 32 minutes (p=0.011). Among patients with moderate Alzheimer's disease, caregivers of galantamine-treated patients were even more likely to report reductions (46% vs 37%), maintenance (15% vs 6%) or smaller increases (25% vs 42% for increases >30 min) vs placebo (p=0.004), with a mean daily time saving of 53 minutes (p=0.021). Caregivers of galantamine-treated patients were more likely to report increases (22% vs 18%), maintenance (45% vs 43%) or smaller reductions (30% vs 37% for reductions >30 minutes) in time the patient could be left unsupervised compared with placebo (p=0.027). Mean daily time saving was 27 minutes. Among patients with moderate Alzheimer's disease, the treatment effect was greater (p=0.029), with caregivers in the galantamine group reporting the change in time left unsupervised as 68 minutes longer each day than caregivers of patients receiving placebo. CONCLUSION: The clinical benefits of galantamine for patients with Alzheimer's disease are also associated with benefits to caregiving.  相似文献   
107.
There has been much recent interest in the cardiovascular benefits of dietary isoflavones. The aim of the present in vitro studies was to investigate potential anti-thrombogenic and anti-atherogenic effects of the isoflavones genistein and daidzein in platelets, macrophages and endothelial cells. Pre-treatment with either isoflavone inhibited collagen-induced platelet aggregation in a dose-dependent manner. In a macrophage cell line (RAW 264.7) activated with interferon gamma plus lipopolysaccharide, both isoflavones were found to inhibit NO production and tumour necrosis factor alpha (TNF-alpha) secretion dose-dependently, but they did not affect mRNA levels for inducible nitric oxide synthase and cyclo-oxygenase-2. Both isoflavones also dose-dependently decreased monocyte chemoattractant protein-1 secretion induced by TNF-alpha in human umbilical vein endothelial cells. Compared with daidzein, genistein exerted greater inhibitory effects for all parameters studied. The present data contributes to our knowledge on the molecular mechanisms by which isoflavones may protect against coronary artery disease. Further studies are required to determine whether the effects of isoflavones observed in the current in vitro studies are relevant to the aetiology of coronary artery disease in vivo.  相似文献   
108.
Using 1998 provincial survey data (n = 1,205), the authors examine responses to 7 items concerning public opinion on alcohol-related policy in Ontario. The purpose of the study is to get a sense of overall public opinion on certain topical policy-related measures and to see whether this opinion is predicted by demographic characteristics of respondents (sex, age and self-reported drinking pattern). Cross-tabulations of opinion items with demographic variables revealed strong majority support for the status quo with regard to number of liquor and beer stores, beer and liquor store hours, and prohibition of the sale of alcohol in corner stores. A somewhat less robust majority also supported the status quo for alcohol taxes and legal drinking age. Among the demographic groups, high-risk heavy drinkers stood out for their greater support of relaxation of controls and this finding was confirmed by means of logistic regression. The majority of all groups, except frequent bar-goers, liked the idea of warning labels on alcoholic beverage containers. The authors conclude that, according to these survey data, policy initiatives towards greater access to alcohol, such as extended liquor store hours and sale of alcohol in corner stores, are not mandated by the majority of the population of Ontario.  相似文献   
109.
gamma-Hydroxybutyric acid (GHB) has been widely associated with drug-facilitated sexual assault (DFSA). However, its excretion profile in man has not been well characterized. To assess the detectability of GHB for forensic cases and to correlate urinary levels with dose, we have examined the excretion profiles of 1- and 2-g doses of GHB (sodium salt) in a healthy male volunteer. The urinary levels were measured by a novel, simple and highly reproducible method. The drug was found to be excreted in small amounts in the free form (0.86 and 1.16% for 1- and 2-g doses, respectively) rapidly in urine (< or = 10 h). The urinary levels were found to be in the low mg L(-1) range (up to 29.1 mg L(-1)). The work presented demonstrates that it is of the utmost importance to collect the samples as soon as possible following the alleged assault.  相似文献   
110.
We have studied the kinetics of oxalate-induced turbidity in fresh human urine and artificial urine. Assays are performed in 96-well plates, which allows many oxalate concentrations to be studied, repeatedly, in a short time. The metastable limit is defined in terms of the lowest oxalate concentration that gives a rate of change of attenuance significantly greater than the control. Interpretation of rates above this limit is based on ln/ln plots of initial rates against added oxalate concentration. This approach has a good theoretical basis, is well supported by our results and gives a turbidity rate index that is related to the product of the growth rate constant and a factor relating to the number and characteristics of the heteronuclei responsible for initiation of crystallization. This interpretation is posited upon the assumptions that second-order crystallization kinetics occur in unseeded urine when supersaturation exceeds the metastable limit and that aggregation during the initial phase of crystallization does not significantly contribute to changes in turbidity. Metastable limits of urine from healthy volunteers corresponded to a calcium oxalate supersaturation ratio of approx. 10. The turbidity rate index was higher in human urine than in artificial urine. The metastable limit, based on either oxalate concentration or supersaturation, for induction of calcium oxalate crystallization in normal human urine is higher than is likely to be found in normal subjects in vivo. The shape of the relationship between the metastable limit (based on oxalate concentration) and calcium concentration emphasizes the benefit of achieving a low urine calcium concentration. Comparison of the turbidity rate indices for human and artificial urine suggests that the role of nucleation promoters is more dominant than that of growth inhibitors.  相似文献   
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