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1.
The goal of the work described here was to assess the performance of Doppler ultrasound (US) of the superior mesenteric artery (SMA) and celiac trunk (CT) in the evaluation of tumor response in female mice with ovarian peritoneal carcinomatosis treated either with bevacizumab or with carboplatin. Compared with untreated mice, carboplatin-treated mice had a lower weight (23.3 ± 2.0 vs. 27.9 ± 2.9 g, p < 0.001), peritoneal carcinomatosis index (PCI, 11 ± 3 vs. 28 ± 6, p < 0.001), Ki67-positive staining surfaces (p < 0.001), vascular density (p < 0.001), mean blood flow velocity (mBFVel) in the SMA (7.0 ± 1.4 vs. 10.9 ± 1.8 cm/s, p < 0.001) and CT (8.0 ± 1.8 vs. 14.3 ± 4.6 cm/s, p < 0.001) and no ascites. Weight and mBFVel were similar in bevacizumab-treated and untreated mice. The mBFVels in the SMA and CT correlated with the PCI used as an estimation of the tumor burden, R = 0.70 (p < 0.0001) and R = 0.65 (p < 0.0001), respectively. Doppler US allows non-invasive assessment of the effects of anticancer therapy in ovarian peritoneal carcinomatosis-induced mice.  相似文献   
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Background:Nursing work environment consists of a number of work-related psychosocial risk factors such as excessive workloads, lack of social support, emotional demands, job insecurity and confronting with challenging situations all of which may induce burnout. The aim of the current study was to investigate the relationship between work-related psychosocial factors and burnout among Iranian nurses.Methods:A cross-sectional study was carried out among 522 nurses. The data related to work-related psychosocial factors and burnout was gathered using Job Content Questionnaire (JCQ) and Maslach Burnout Inventory (MBI), respectively. Pearson’s correlation coefficients were used to examine the relationship between work-related psychosocial factors and burnout.Results:Mean scores of the dimensions of burnout for emotional exhaustion, depersonalization, and reduced personal accomplishment were 13.6 (SD=8.6), 18.42 (SD=7.1), and 28.45 (SD= 9.15), respectively. Psychological and physical job demands were positively correlated with different dimensions of burnout while social support and job control showed negative correlation with them.Conclusion:Appropriate interventions on reducing job demands both psychologically and physically and increasing social support and job control are suggested in prevention of burnout among the studied nurses.Key words: Burnout, psychosocial factors, nurses, job demands, job control, social support  相似文献   
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Background:Modern technology has reduced physical workload and imposed high mental workload on the control room operators in industrial settings. The present study was conducted among control room operators to assess their mental workload, investigate their workability, examine the relationship between mental workload and workability, and determine the factors associated with workability.Methods:This cross-sectional study was carried out among 213 control room operators in six Iranian process industries. Task Load Index (NASA-TLX) was used to assess the mental workload, and Work Ability Index (WAI) was used to determine workability. The relationships between demographic characteristics and dimensions of mental workload and workability were examined by univariate tests. Logistic regression analysis was also used to determine the factors associated with the operators’ workability.Results:The results showed a high mental workload in the study population (82.38±8.8). Yet, the operators showed a good and excellent level of workability (56.4%). Pearson’s correlation coefficient revealed a significant inverse linear relationship between the mean score of mental workload and workability (r=-0.581). Besides, regression modeling demonstrated that mental demand (OR=0.90), temporal demand (OR=0.90), effort (OR=0.91), frustration (OR=0.92), from NASA-TLX subscales were significantly associated with workability. Moreover, mental and temporal demands were important factors associated with reduced workability.Conclusion:Monitoring tasks imposes high mental workload on the control room operators, which may result in adverse effects on their workability as well as on the safety of the system.Key words: Mental workload, NASA-TLX, work ability, control room  相似文献   
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Aim: To examine the efficacy of cognitive rehabilitation treatment (CRT) for people with opioid use disorder who were recruited into a methadone maintenance treatment (MMT) programme.

Method: 120 male subjects were randomly assigned to (1) MMT plus CRT in two months or (2) MMT plus a control intervention. Subjects were assessed at the beginning, mid-point and post-intervention as well as at 1-, 3- and 6-month follow-up time points.

Results: Analysis with repeated measure ANOVA showed that the CRT group performed significantly better in tests of learning, switching, processing speed, working memory and memory span. Moreover, the CRT group had significantly lower opiate use over the control group during 3-months follow-up. Analysis including only those with a history of methamphetamine use showed that the CRT group had significantly lower amphetamine use. No group differences were observed for treatment retention.

Conclusions: Our findings provide evidence that adding CRT as an adjunct intervention to MMT can improve cognitive performance as well as abstinence from both opiates and stimulants.  相似文献   

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Purpose: Traffic accidents are one of the major health problems in the world, being the first cause of burden of illness and the second leading cause of death in Iran. The Sistan-Baluchestan province is one of the most accidental provinces of Iran with the highest rate of accidents-caused deaths. This study was conducted to determine the risk factors associated with traffic accidents in Zahedan through 2013 to 2016. Methods: This analytical cross-sectional study was carried out on 223 drivers from Zahedan who were traumatized by traffic accident and sent to Zahedan hospitals. The data were obtained through interviews taken by the trained interviewers via refereeing to the medical records and collected in the researcher-made checklist. Census was obtained from the study subjects. For data analysis, independent t-test, one-way ANOVA, Chi-square and logistic regression were used with the Stata software version 11.0. Results: In this study, 223 male subjects with the mean age of (32.54 ± 12.95) years, 39.8% single and 60.2% married, entered for investigation. Most accidents (38.8%) occurred between 12:00 to 17:59. While driving, 47.1% of the study subjects were using cell phones, 89.1% had manual use of mobile phones, 21.9% had a habit of sending short message service (SMS) and 23.4% had sent SMS within 10 min before the accident. The one way analysis of variance showed that the mean age of individuals with marital status, driving experience, education and accident with motorcycle were significantly different (p < 0.05). Also, the multivariate logistic regression test indicated a significant relationship of smoking, ethnicity, insurance and SMS typing while driving with motorcycle accident (p < 0.05). Conclusion: In this study, SMS and smoking while driving had the highest risk among the variables studied in the motorcycle accidents. Therefore, effective education attempting to enhance people''s awareness about the consequences of using cell phone and smoking during driving to reduce traffic accidents seems necessary.  相似文献   
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BackgroundAcetylcholine deficiencies in hippocampus and cortex, aggregation of β-amyloid, and β-secretase over activity have been introduced as main reasons in pathogenesis of Alzheimer’s disease.MethodsColorimetric Ellman’s method was used for determination of IC50 value in AChE and BChE inhibitory activity. The kinetic studies, neuroprotective and β-secretase inhibitory activities, evaluation of inhibitory potency on β-amyloid (Aβ) aggregations induced by AChE, and docking study were performed for prediction of the mechanism of action.Result and discussionA new series of cinnamic acids-tryptamine hybrid was designed, synthesized, and evaluated as dual cholinesterase inhibitors. These compounds demonstrated in-vitro inhibitory activities against acetyl cholinesterase (AChE) and butyryl cholinesterase (BChE). Among of these synthesized compounds, (E)-N-(2-(1H-indol-3-yl)ethyl)-3-(3,4-dimethoxyphenyl)acrylamide (5q) demonstrated the most potent AChE inhibitory activity (IC50 = 11.51 μM) and (E)-N-(2-(1H-indol-3-yl)ethyl)-3-(2-chlorophenyl)acrylamide (5b) were the best anti-BChE (IC50 = 1.95 μM) compounds. In addition, the molecular modeling and kinetic studies depicted 5q and 5b were mixed type inhibitor and bound with both the peripheral anionic site (PAS) and catalytic sites (CAS) of AChE and BChE. Moreover, compound 5q showed mild neuroprotective in PC12 cell line and weak β-secretase inhibitory activities. This compound also inhibited aggregation of β-amyloid (Aβ) in self-induced peptide aggregation test at concentration of 10 μM.ConclusionIt is worth noting that both the kinetic study and the molecular modeling of 5q and 5b depicted that these compounds simultaneously interacted with both the catalytic active site and the peripheral anionic site of AChE and BChE. These findings match with those resulted data from the enzyme inhibition assay. Graphical abstractOpen in a separate windowA new series of cinnamic-derived acids-tryptamine hybrid derivatives were designed, synthesized and evaluated as butyrylcholinesterase (BChE) and acetylcholinesterase (AChE) inhibitors and neuroprotective agents. Compound 5b and 5q, as the more potent compounds, interacted with both the peripheral site and the choline binding site having mixed type inhibition. Results suggested that derivatives have a therapeutic potential for the treatment of AD.Electronic supplementary materialThe online version of this article (10.1007/s40199-020-00346-9) contains supplementary material, which is available to authorized users.  相似文献   
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Exendin-4 is now considered as a promising drug for the treatment of cerebral ischemia. To determine the neuroprotective effects of intranasal exendin-4, C57BL/6J mice were intranasally administered with exendin-4 daily for 7 days before middle cerebral artery occlusion (MCAO) surgery. Intranasally administered exendin-4 produced higher brain concentrations and lower plasma concentrations when compared to identical doses administered interperitoneally. Neurological deficits and volume of infarcted lesions were analyzed 24 h after ischemia. Intranasal administration of exendin-4 exhibited significant neuroprotection in C57BL/6 mice subjected to MCAO by reducing neurological deficit scores and infarct volume. The neuroprotective effects of exendin-4 were blocked by the knockdown of GLP-1R with shRNA. However, exendin-4 has no impact on glucose and insulin levels which indicated that the neuroprotective effect was mediated by the activation of GLP-1R in the brain. Exendin-4 intranasal administration restored the balance between pro- and anti-apoptotic proteins and decreased the expression of Caspase-3. The anti-apoptotic effect was mediated by the cAMP/PKA and PI3K/Akt pathway. These findings provided evidence that exendin-4 intranasal administration exerted a neuroprotective effect mediated by an anti-apoptotic mechanism in MCAO mice and protected neurons against ischemic injury through the GLP-1R pathway in the brain. Intranasal delivery of exendin-4 might be a promising strategy for the treatment of ischemic stroke.  相似文献   
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