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91.
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
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Camilo Jaimes Fedel Machado‐Rivas Onur Afacan Shadab Khan Bahram Marami Cynthia M. Ortinau Caitlin K. Rollins Clemente Velasco‐Annis Simon K. Warfield Ali Gholipour 《Human brain mapping》2020,41(12):3177-3185
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
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Onur Sinan Deveci Caglar Ozmen Muhammet Bugra Karaaslan Aziz Inan Celik Hatice Rahimova Anil Akray Omer Tepe Emel Gurkan Ali Deniz 《Medical principles and practice》2022,31(1):47
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
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Nuran Katgi Pinar imen Ali Kadri irak Tarik imek Kenan Can Ceylan
zgür Samancilar Elif Duman Onur Fevzi Erer Fatma Fevziye Tuksavul 《Sarcoidosis, vasculitis, and diffuse lung diseases : official journal of WASOG / World Association of Sarcoidosis and Other Granulomatous Disorders》2022,39(1)
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
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Genc K Genc S Kizildag S Sonmez U Yilmaz O Tugyan K Ergur B Sonmez A Buldan Z 《Brain research》2003,982(1):125-130
We investigated whether the psychostimulant methamphetamine (METH) has a cytotoxic effect on oligodendrocytes and which cell-death pathways are involved in the cytotoxic process. METH caused concentration- and time-dependent cytotoxicity in rat oligodendrocyte cultures. METH induced apoptotic cell death and mRNA expression of pro-apoptotic proteins (bax and DP5), but not anti-apoptotic proteins (bcl-2 and bcl-XL). These results suggest that METH induces cytotoxicity in rat oligodendrocytes via the differential regulation of the expression of genes involved in the apoptotic process. 相似文献
98.
NSF workshop report: Discovering general principles of nervous system organization by comparing brain maps across species 下载免费PDF全文
Georg F. Striedter T. Grant Belgard Chun‐Chun Chen Fred P. Davis Barbara L. Finlay Onur Güntürkün Melina E. Hale Julie A. Harris Erin E. Hecht Patrick R. Hof Hans A. Hofmann Linda Z. Holland Andrew N. Iwaniuk Erich D. Jarvis Harvey J. Karten Paul S. Katz William B. Kristan Eduardo R. Macagno Partha P. Mitra Leonid L. Moroz Todd M. Preuss Clifton W. Ragsdale Chet C. Sherwood Charles F. Stevens Maik C. Stüttgen Tadaharu Tsumoto Walter Wilczynski 《The Journal of comparative neurology》2014,522(7):1445-1453
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
99.
Background The aim of this study is to investigate the presence of condylar and ramal asymmetry in patients with a cyst larger than 10 mm in the maxilla or mandible.Material and Methods Condylar and ramal asymmetry index measurements of 47 patients (mean age: 28.85 ± 15.348) in the study group and 40 patients in the control group (mean age: 33.73 ± 13.095) were performed using panoramic radiographs. The study group consists of patients with cysts larger than 10 mm in diameter in the maxilla or mandible. The control group consisted of patients with no radiolucent lesions and no history of trauma. The possible statistical difference between the groups was evaluated by the Mann-Whitney U test.Results No statistically significant difference was observed in asymmetry indices according to gender and the jaw (maxilla or mandible) in which the cyst was located. However, it was determined that CAI and RAI values were statistically significantly different between the study and control groups (p = 0.047 and p = 0.016, respectively).Conclusions The presence of intraosseous cysts larger than 10 mm in the jaws was found to be associated with condylar and ramal asymmetry. Key words:Condylar asymmetry, ramal asymmetry, odontogenic cysts 相似文献
100.
Zuhal Karagoz Genc Sibel Selcuk Suleyman Sandal Naki Colak Serhat Keser Memet Sekerci Mustafa Karatepe 《Medicinal chemistry research》2014,23(5):2476-2485
Novel six Cu(II), Ni(II), and Zn(II) complexes with Schiff bases derived from 4-aminobenzoic acid with terephtaldehyde and amino acids (glycine, β-alanine). Structures have been proposed from elemental analysis, UV–Vis, IR, NMR, TGA, DTA, and magnetic measurements. Spectroscopic studies suggest that coordination occurs through azomethine nitrogen, hydroxyl group, and carbonyl oxygen of the ligands to the metal ions. The elemental analyses of the complexes where L is Schiff base ligands, are confined to the stoichiometry of the type M2L2(CH3COO)2 [M = Cu(II)]; and M2L(CH3COO)2 [M = Ni(II) and Zn(II)]. The cytotoxicity activities of the compounds against human breast carcinoma MCF-7 cell line have been studied. Ligands and their Zn(II) compounds inhibited cell proliferation of MCF-7 cancer cell lines in a dose- and time-dependent manner. The free radical scavenging activity was measured by 1,1-diphenyl-2-picryl-hydrazil. Our results show that the synthesized compounds induced oxidative damage by increasing the lipid peroxidation in yeast since MDA formation was increased, and it could be concluded that the synthesized compounds caused oxidative stress. In addition, the antioxidant activities of the synthesized compounds were very much lower than those of standard antioxidants. 相似文献