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Metabolomics may reveal novel insights into the etiology of prostate cancer, for which few risk factors are established. We investigated the association between patterns in baseline plasma metabolite profile and subsequent prostate cancer risk, using data from 3,057 matched case–control sets from the European Prospective Investigation into Cancer and Nutrition (EPIC). We measured 119 metabolite concentrations in plasma samples, collected on average 9.4 years before diagnosis, by mass spectrometry (AbsoluteIDQ p180 Kit, Biocrates Life Sciences AG). Metabolite patterns were identified using treelet transform, a statistical method for identification of groups of correlated metabolites. Associations of metabolite patterns with prostate cancer risk (OR1SD) were estimated by conditional logistic regression. Supplementary analyses were conducted for metabolite patterns derived using principal component analysis and for individual metabolites. Men with metabolite profiles characterized by higher concentrations of either phosphatidylcholines or hydroxysphingomyelins (OR1SD = 0.77, 95% confidence interval 0.66–0.89), acylcarnitines C18:1 and C18:2, glutamate, ornithine and taurine (OR1SD = 0.72, 0.57–0.90), or lysophosphatidylcholines (OR1SD = 0.81, 0.69–0.95) had lower risk of advanced stage prostate cancer at diagnosis, with no evidence of heterogeneity by follow-up time. Similar associations were observed for the two former patterns with aggressive disease risk (the more aggressive subset of advanced stage), while the latter pattern was inversely related to risk of prostate cancer death (OR1SD = 0.77, 0.61–0.96). No associations were observed for prostate cancer overall or less aggressive tumor subtypes. In conclusion, metabolite patterns may be related to lower risk of more aggressive prostate tumors and prostate cancer death, and might be relevant to etiology of advanced stage prostate cancer.  相似文献   
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Background  

Patient falls in hospitals are common and may lead to negative outcomes such as injuries, prolonged hospitalization and legal liability. Consequently, various hospital falls prevention programs have been implemented in the last decades. However, most of the programs had no sustained effects on falls reduction over extended periods of time.  相似文献   
4.
Background. Partial harvesting of the left internal mammary artery (LIMA) is a widespread technique used during minimally invasive coronary operations performed through a left anterior small thoracotomy. The influence of persisting LIMA branches was investigated to evaluate their effect on the blood flow of the left anterior descending artery.

Methods. Thirty patients, 15 with totally (group A) and 15 with partially (group B) harvested LIMAs, were evaluated. All the patients underwent postoperative angiography, during which a flow map of the LIMA was performed. The average peak velocity and the diastolic-to-systolic peak velocity ratio were recorded. The LIMA graft flow pattern was recorded in the proximal and distal thirds of the artery. Intramammary adenosine (12 to 14 μg) was injected and the average peak velocities before and after injection were calculated.

Results. The average peak velocity was similar in both groups in the proximal and distal thirds of the LIMA (25 ± 7 and 26 ± 5 cm/sec, respectively, in group A versus 27 ± 5 and 25 ± 5 cm/sec, respectively in group B; p = NS). The diastolic-to-systolic peak velocity ratio was similar proximally (0.78 ± 0.3 in group A versus 0.69 ± 0.3 cm/s in group B; p = NS), but not distally (1.72 ± 0.1 in group A versus 0.97 ± 0.3 in group B; p < 0.0005). The LIMA graft flow reserve was similar both proximally and distally (2.6 ± 0.6 and 2.5 ± 0.3 cm/s, respectively, in group A versus 2.6 ± 0.5 and 2.6 ± 0.3 cm/s, respectively, in group B; p = NS).

Conclusions. The persistence of LIMA branches does not influence the blood flow of the left anterior descending artery after acute adenosine-induced myocardial hyperemia. If a left anterior small thoracotomy is used in left anterior descending artery direct revascularization, complete LIMA harvesting is not mandatory and depends on the personal preference of the surgeon.  相似文献   

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BACKGROUND: Growing evidence indicates that the entorhinal cortex (ECx) might be affected in schizophrenia (SZ) and bipolar disorder (BD). To test whether distinct interneuronal subpopulations might be altered, numbers of parvalbumin-immunoreactive (PVB-IR) neurons were measured in the ECx of BD and SZ subjects. These neurons play a pivotal role within ECx intrinsic circuits. METHODS: Numbers, numerical density, and soma size of PVB-IR neurons were measured in the ECx of normal control (n = 16), BD (n = 10), and SZ (n = 10) subjects. The volume of the ECx was measured in Nissl-stained sections. RESULTS: In BD, decreases of total numbers (p = .02) and numerical densities (p = .01) of PVB-IR neurons were detected in the ECx. Within distinct subregions, reductions were detected in the superficial layers of the lateral (p = .02), intermediate (p = .04), and caudal (p = .01) ECx. In SZ, total numbers and numerical densities were not altered. A reduction of soma size was present in the intermediate ECx (p = .01). Volume was unaffected in either disorder. CONCLUSIONS: In BD, a decrease of PVB-IR neurons may alter intrinsic inhibitory networks within the superficial layers of the ECx. The likely consequence is a disruption of integration and transfer of information from the cerebral cortex to the hippocampus.  相似文献   
7.
The pharmacotherapy of schizophrenia remains an ongoing challenge for researchers and clinicians alike. Current medications remain suboptimal to effectively treat this illness despite the recent surge of what are considered to be better antipsychotics: the atypicals. The atypicals cause fewer extrapyramidal symptoms and tardive dyskinesia, but there is growing concern regarding the significant long-term metabolic and cardiac adverse effects of these novel antipsychotics. There are differences among the atypicals in their propensity to produce these adverse effects, and clinicians should weigh the risk-benefit ratio for each drug with each individual patient. Diabetes, heart disease, obesity, and unhealthy lifestyle choices are on the rise in the general population, and individuals with chronic schizophrenia are even more at risk. The dilemma clinicians face in trying to avoid the neurological morbidity of the typicals (extrapyramidal side effects and tardive dyskinesia) is the risk of consequently exposing patients to both the morbidity and potential mortality of the atypicals (cardiovascular, endocrine, and metabolic adverse effects). The importance of baseline investigations and monitoring at regular intervals as well as identification of patients at risk for obesity, diabetes, and cardiovascular morbidity has become crucial. Informed decision making is essential for successful antipsychotic pharmacotherapy. For a condition, which often necessitates long-term pharmacotherapy, the importance of prevention and (or) minimization of morbidity and mortality related to adverse effects of such pharmacotherapy cannot be understated.  相似文献   
8.
The reactivity of vesicular stomatitis virus (VSV) with kethoxal can be appreciably altered by treatment with 1-guanyl-3, 5-dimethyl pyrazole nitrate (GDMP) and proteolytic enzymes. Pretreatment of purified VSV with GDMP or proteolytic enzymes markedly reduced the effectiveness of kethoxal as a virucide. The rate of neutralizability of GDMP- and trypsin-treated viruses by specific antiserum differed from that of controls.  相似文献   
9.
An open-label randomized pilot study was conducted to evaluatethe efficacy and acceptability of 6 months treatment with leuprolidein a 3-monthly versus a monthly i.m. depot injection for therelief of chronic pelvic pain in women with endometriosis. Atotal of 30 women aged 18-38 years were allocated to the 3-monthlydepot arm (n = 15) or to the monthly depot arm (n = 15) afterlaparoscopic diagnosis of pelvic endometriosis. Mean (SD) deepdys-pareunia scores according to a 0–3 point verbal ratingscale decreased from 1.8 (0.9) at baseline to 1.3 (0.7) at theend of treatment in the 3-monthly depot group and from 2.1 (1.2)to 1–3 (0.7) in the monthly depot group. Correspondingvalues in non-menstrual pain scores fell from 2.1 (0.6) to 1.1(03), and from 2.1 (0.8) to 1.2 (0.4) respectively, withoutstatistically significant differences between the groups. Serumluteinizing hormone (LH) and 17-oestradiol concentrations weresignificantly suppressed at 12 and 24 weeks compared with baselinevalues, without differences between the groups. The monthlydepot caused a slightly more marked inhibition of serum folliclestimulating hormone (FSH) levels with respect to the 3-monthlypreparation. Mean (SD) endometriosis scores at baseline andat 6-month follow-up laparoscopy were respectively 32.8 (25.1)and 12.2 (9.3) in the 3-monthly depot group and 29.0 (22.7)and 13.1 (15.3) in the monthly depot group (paired Mest, P 0.05). Mean percentage decrease in lumbar spine bone mineraldensity was 5.2% in the former and 4.9% in the latter subjects.In the 3-monthly depot group, 13 women graded the tolerabilityof their treatment schedule as ‘good’ compared withseven in the monthly depot group (2 = 5.40, P = 0.02).  相似文献   
10.
Recently developed PCR systems offer online-monitoring of amplification and allow simple and reliable DNA quantification. We have used the LightCycler system to develop a simple and rapid method for direct identification of female carriers of deletions and duplications in the dystrophin gene. The challenge resides in the ability to identify the presence of a deleted or duplicated allele over the background contributed by the normal allele. Quantification is based on the determination of the ratio between potentially deleted/duplicated dystrophin exons and non-deleted/-duplicated reference exons using the unspecific dsDNA-dye SYBRgreen I. In a retrospective study, we evaluated our method in female relatives of DMD/BMD patients with known carrier status by comparative analysis of deleted or duplicated versus non-deleted/-duplicated exons. Carrier status was accurately attributed in 100% of cases, the mean ratios being 0.52+/-0.12 for deletion carriers (expected value: 0.5) and 1.56+/-0.18 for duplication carriers (expected value: 1.5) vs. 1.022+/-0.17 for non-carriers (expected value: 1.0). The method proved to be simple, rapid, reliable, and cost-effective. It may be used for direct determination of deletions/duplications in potential DMD/BMD carriers and may easily be adapted for other genetic conditions involving deletions and duplications.  相似文献   
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