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91.

Purpose

Taurine, the major intracellular free amino acid found in high concentrations in mammalian cells, is known to be an endogenous antioxidant and a membrane-stabilizing agent. It was hypothesized that taurine may be effective in reducing ischemia–reperfusion injury after lung transplantation and an experimental study was conducted in a rat model.

Methods

The number of Sprague–Dawley rats used in the study was 35. Animals were randomized into five groups of 7 rats each, including control, donor I, donor II, ischemia–reperfusion injury, and treatment groups. All animals were exposed to the same experimental conditions in the preoperative period. Rats were fixed in a supine position after the induction. After the rats were shaved, a left pneumonectomy was performed following sternotomy in control, donor I, and donor II groups. The harvested grafts in donor I and donor II groups were transplanted to the rats of the ischemia–reperfusion group and treatment group, respectively. However, taurine was administered intraperitoneally for 3 days before the harvesting procedure in donor II. All harvested lungs were kept in a Euro-Collins solution at +4 °C for 24 h in a half-inflated manner. After harvesting and transplantation, lungs were sampled for histopathological and biochemical analysis.

Results

Malondialdehyde and superoxide dismutase, glutathione peroxidase, and catalase levels were lower in the treatment group than the other groups (p < 0.05). Histopathological findings were better in treatment group than the ischemia–reperfusion group (p < 0.05).

Conclusion

It was demonstrated that donor treatment with taurine resulted in preservation of transplanted lung tissue in respect to histopathological and biochemical findings.  相似文献   
92.
Possible benefits of vitamin K on bone health, fracture risk, markers of bone formation and resorption, cardiovascular health, and cancer risk in postmenopausal women have been investigated for over three decades; yet there is no clear evidence-based universal recommendation for its use.  相似文献   
93.
Vitamin E is known to be the most important antioxidant in the body, protecting against the effects of toxic radicals. The main idea behind the studies on vitamin E and bone metabolism stems from the concept that oxidative stress may interfere with the bone formation activity of osteoblasts which in turn can lead to osteoporosis. This mini-review, summarizes the studies on the effects of vitamin E on bone mineral density, fracture risk, bone formation, and resorption markers in perimenopausal women. Current evidence does not the support daily use of vitamin E for protection against osteoporosis and hip fracture risk in perimenopausal women. However some benefit has been shown in some observational studies. Low vitamin E (>6.2 mg/day) intake seems to be associated with an OR of 3.0 of hip fracture in current smokers. Compared with the highest quintile of alpha-tocopherol intake, the lowest quintile of intake conferred a multivariable-adjusted HR of 1.86 for hip fracture and 1.20 for any fracture. Alpha-tocopherol supplementation may alter the alpha-tocopherol/gamma-tocopherol ratio; which in turn may be associated with decreased osteoblastic activity. Interventional studies, especially randomized controlled trials (RCT), evaluating a possible causal relationship between serum vitamin E levels and BMD and hip fracture risk in perimenopausal women are needed.  相似文献   
94.
Congenital megalourethra is a rare urogenital malformation characterized by severe dilatation and elongation of the penile urethra. It causes functional obstruction of the lower urinary system. Herein, we present a newborn with congenital megalourethra with single umbilical artery.  相似文献   
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The third trimester of pregnancy is a period of rapid development of fiber bundles in the fetal white matter. Using a recently developed motion‐tracked slice‐to‐volume registration (MT‐SVR) method, we aimed to quantify tract‐specific developmental changes in apparent diffusion coefficient (ADC), fractional anisotropy (FA), and volume in third trimester healthy fetuses. To this end, we reconstructed diffusion tensor images from motion corrected fetal diffusion magnetic resonance imaging data. With an approved protocol, fetal MRI exams were performed on healthy pregnant women at 3 Tesla and included multiple (2–8) diffusion scans of the fetal head (1–2 b = 0 s/mm2 images and 12 diffusion‐sensitized images at b = 500 s/mm2). Diffusion data from 32 fetuses (13 females) with median gestational age (GA) of 33 weeks 4 days were processed with MT‐SVR and deterministic tractography seeded by regions of interest corresponding to 12 major fiber tracts. Multivariable regression analysis was used to evaluate the association of GA with volume, FA, and ADC for each tract. For all tracts, the volume and FA increased, and the ADC decreased with GA. Associations reached statistical significance for: FA and ADC of the forceps major; volume and ADC for the forceps minor; FA, ADC, and volume for the cingulum; ADC, FA, and volume for the uncinate fasciculi; ADC of the inferior fronto‐occipital fasciculi, ADC of the inferior longitudinal fasciculi; and FA and ADC for the corticospinal tracts. These quantitative results demonstrate the complex pattern and rates of tract‐specific, GA‐related microstructural changes of the developing white matter in human fetal brain.  相似文献   
98.
ObjectiveVaso-occlusive crisis (VOC) is a common clinical manifestation of sickle cell anemia (SCA) and is associated with increased proinflammatory mediators. Copeptin is the C-terminal part of the prohormone for provasopressin and seems clinically relevant in various clinical conditions. Right ventricular (RV) dysfunction significantly appears in SCA patients due to pulmonary hypertension. This study aimed to investigate the association of copeptin levels in VOC patients and evaluate RV dysfunction.Materials and MethodsA total of 108 patients were enrolled in the study. Twenty-eight SCA patients in steady state (30.2 ± 0.9 years), 25 SCA patients in VOC (36.8 ± 11.8 years), and 55 healthy individuals (31.9 ± 9.4 years) with HbAA genotype were included. Clinical, echocardiographic, and laboratory data were recorded. ELISA was used for the determination of serum levels of copeptin.ResultsVOC patients had significantly higher copeptin level compared both with controls and SCA subjects in steady state (22.6 ± 13.0 vs. 11.3 ± 5.7 pmol/L, 22.6 ± 13.0 vs. 12.4 ± 5.8 pmol/L, p = 0.009 for both). Additionally, the copeptin level was significantly higher in SCA patients with RV dysfunction than those without RV dysfunction (23.2 ± 12.2 vs. 15.3 ± 9.5 pmol/L, p = 0.024). Multiple logistic regression analysis revealed that high-sensitivity C-reactive protein and copeptin levels were found to be associated with VOC.ConclusionThis study showed that copeptin and hs-CRP levels were increased in patients with VOC, and it was found that RV dysfunction was more common in SCA patients with VOC than in the control group. Copeptin can be considered for use as a potential biomarker in predicting VOC crisis in SCA patients and in the early detection of patients with SCA who have the potential to develop RV dysfunction.  相似文献   
99.
Aim and introduction:Diagnosing of interstitial lung disease (ILD) is difficult and expensive. The standard diagnostical approaches to ILD are bronchoalveolar lavage, transbronchial lung biopsy, transbronchial lung cryobiopsy (TBLC) and surgical lung biopsy (SLB). SLB is gold standard for the confident diagnosis of ILD but because of the poor performance of the patients it’s use is limited. We conducted a retrospective study to point out that TBLC plays an important role in diagnosis of ILD and has fewer complications and lower cost than awake video-assisted thoracic surgery (AVATS).Material and methods:132 patients who underwent TBLC and AVATS with a pre-diagnosis of ILD in our hospital between 2015 and 2020 were evaluated retrospectively. Diagnosis rates, complications and costs were recorded.Results:There were no non-diagnostic materials in 44 patients in AVATS arm. Prolonged air leak was observed in 11(25.0%) of the patients, and six of them (13.6%) were discharged with Heimlich Valve (HV). Median length of stay in the hospital was 8 days, while average patient cost was $515.9 (415.2-2662.9) in the AVATS arm. Non-diagnostic material was obtained from 10 (11.3%) of 88 patients in TBLC arm. Six (6.8%) of them had pneumothorax, only one of them required a chest tube. No patient was discharged with HV (p=0.001). Median cost for each patient with a median hospital stay of 2.0 (1.0-21.0) (p<0.001) days was $171.9 (80.8-1493.3) (p<0.001).Discussion:Although TBLC is behind AVATS in terms of diagnostic accuracy, it may be an alternative diagnostic tool in the diagnosis of interstitial lung disease due to its acceptable safety profile and cost-effectiveness.  相似文献   
100.
Efforts to understand nervous system structure and function have received new impetus from the federal Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative. Comparative analyses can contribute to this effort by leading to the discovery of general principles of neural circuit design, information processing, and gene‐structure‐function relationships that are not apparent from studies on single species. We here propose to extend the comparative approach to nervous system ‘maps' comprising molecular, anatomical, and physiological data. This research will identify which neural features are likely to generalize across species, and which are unlikely to be broadly conserved. It will also suggest causal relationships between genes, development, adult anatomy, physiology, and, ultimately, behavior. These causal hypotheses can then be tested experimentally. Finally, insights from comparative research can inspire and guide technological development. To promote this research agenda, we recommend that teams of investigators coalesce around specific research questions and select a set of ‘reference species' to anchor their comparative analyses. These reference species should be chosen not just for practical advantages, but also with regard for their phylogenetic position, behavioral repertoire, well‐annotated genome, or other strategic reasons. We envision that the nervous systems of these reference species will be mapped in more detail than those of other species. The collected data may range from the molecular to the behavioral, depending on the research question. To integrate across levels of analysis and across species, standards for data collection, annotation, archiving, and distribution must be developed and respected. To that end, it will help to form networks or consortia of researchers and centers for science, technology, and education that focus on organized data collection, distribution, and training. These activities could be supported, at least in part, through existing mechanisms at NSF, NIH, and other agencies. It will also be important to develop new integrated software and database systems for cross‐species data analyses. Multidisciplinary efforts to develop such analytical tools should be supported financially. Finally, training opportunities should be created to stimulate multidisciplinary, integrative research into brain structure, function, and evolution. J. Comp. Neurol. 522:1445–1453, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
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