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41.
Manoj Kumar Reddy Somagutta Nishat Shama Maria Kezia Lourdes Pormento Ravi Pankajbhai Jagani Ngaba Neguemadji Ngardig Klodin Ghazarian Greta Mahmutaj Khaled El-Faramawy Ashwini Mahadevaiah Molly Sanjay Jain 《Reumatologia》2022,60(1):63
Statins are a class of lipid-lowering medications used worldwide by millions of people and are safe for frequent use in most patients. However, they cause necrotizing autoimmune myopathy in some patients. We reviewed case reports of 80 patients from 2010 to present diagnosed with statin-induced necrotizing autoimmune myopathy (SINAM), aiming to analyze the clinical, physiological, serologic characteristics and outcomes of SINAM. The mean age of these patients was 66 ±9.4, the majority being male (61.3%). All patients reported proximal muscle weakness, and a few had myalgias, extra muscular symptoms such as dysphagia, and pulmonary complications. Most of the patients were on atorvastatin, simvastatin, or rosuvastatin. The mean creatine kinase was 10,094.2 ±7,351.7 U/l, and anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase enzyme was positive for 93.8% of patients. The majority of patients were started on steroids; other treatments were also used. Prompt cessation of statins and initiation of immunosuppressants reduced morbidity and mortality. 相似文献
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Ravi Mahalingam Brittany Feia Colin Coleman Kusala Anupindi Pratush Saravanan Amalia Luthens Amalia Bustillos Arpita Das Eileen de Haro Lara Doyle-Meyers Jayme Looper Andrew N. Bubak Christy S. Niemeyer Brent Palmer Maria A. Nagel Vicki Traina-Dorge 《Viruses》2022,14(6)
Primary simian varicella virus (SVV) infection and reactivation in nonhuman primates is a valuable animal model in the study of varicella zoster virus disease [varicella (chickenpox) and herpes zoster (shingles)]. To understand SVV pathogenesis in skin, we inoculated 10 rhesus macaques with SVV, resulting in varicella rash. After the establishment of latency, eight of the monkeys were immunosuppressed using tacrolimus with or without irradiation and prednisone and two monkeys were not immunosuppressed. Zoster rash developed in all immunosuppressed monkeys and in one non-immunosuppressed monkey. Five monkeys had recurrent zoster. During varicella and zoster, SVV DNA in skin scrapings ranged from 50 to 107 copies/100 ng of total DNA and 2–127 copies/100 ng of total DNA, respectively. Detection of SVV DNA in blood during varicella was more frequent and abundant compared to that of zoster. During varicella and zoster, SVV antigens colocalized with neurons expressing β-III tubulin in epidermis, hair follicles, and sweat glands, suggesting axonal transport of the virus. Together, we have demonstrated that both SVV DNA and antigens can be detected in skin lesions during varicella and zoster, providing the basis for further studies on SVV skin pathogenesis, including immune responses and mechanisms of peripheral spread. 相似文献
44.
Ravi A Mallika A Sama V Begum AS Khan RS Reddy BM 《Journal of ethnopharmacology》2011,137(3):1353-1359
Ethnopharmacological relevance
The bark of Tecomella undulata is primarily used in the treatment of syphilis, painful swellings and cancer by traditional healers. Also, it is claimed to be useful in treating urinary discharges, enlargement of spleen, leucorrhoea, leukoderma, tumors, liver disorders, gonorrhea, gout and promotes wound healing in Indian traditional system of medicine.Aim
To establish a scientific validation for the antitumor effects of Tecomella undulata bark and explore the mechanistic pathway in chronic myeloid leukemia cell line, K562. The study was further extended to standardize the extract using quercetin as biomarker.Methods
Induction of apoptosis by chloroform extract of Tecomella undulata bark (CTUB) was determined by MTT, Annexin V and caspase activation assays. The cell cycle analysis was done by flow cytometer and nuclear staining by DAPI. The standardization of the extract was performed through reverse phase-HPLC method under PDA detection.Result
Results clearly showed the induction of apoptosis by CTUB in K562 cells. The effect was found to be dose dependent, having IC50 of 30 μg/ml with activation of FAS, FADD, caspase 8, caspase 3/7 and fragmentation of DNA. The bioactive CTUB was determined to possess 0.03% (w/w) of quercetin.Conclusion
The investigation clearly demonstrated the potential antitumor effect of CTUB, thereby validating the traditional claim. Quercetin, known to have anticancer activity is being reported and quantified for the first time from the bark of Tecomella undulata. 相似文献45.
46.
Ravi K. Ponnappan Hassan Serhan Brett Zarda Ravi Patel Todd Albert Alexander R. Vaccaro 《The spine journal》2009,9(3):263-267
Background contextPolyetheretherketone (PEEK) has been increasingly used as a biomaterial for spinal implants. PEEK lumbar fusion rods have recently become available for use in posterior lumbar fusion procedures.PurposeTo compare Polyetheretherketone Rod System to traditional titanium rod fixation in a cadaveric model and provide mechanical test data for the PEEK system.Study designBiomechanical testing.MethodsCadaveric biomechanical testing was conducted to compare Expedium 5.5 mm PEEK rods to titanium rods of equivalent diameter. Biomaterials testing was performed to determine static and dynamic performance of Expedium 5.5 mm PEEK rods with 6% BaSo4 in compressive bending and torsion.ResultsCadaveric testing demonstrated that PEEK rods can significantly reduce the range of motion of a destabilized segment. The testing showed no significant difference in the stability provided by PEEK and titanium rods in posterolateral fusion (PLF) or posterior lumbar interbody fusion (PLIF) constructs. PEEK static compressive bending tests showed 67 degrees displacement without fracture of the rod. Torsion testing showed 30 degrees of rotation without yield or plastic deformation. Dynamic compression testing revealed two fatigue runouts at 23 degrees.ConclusionsPEEK rods provide comparable stability to titanium rods of equivalent diameter in cadaveric testing. Mechanical testing suggests PEEK rods can withstand far beyond the angular displacements suggested by cadaveric testing and that of normal physiologic range of motion. Potential advantages to PEEK rods include better anterior column load sharing, reduced stress at bone-to-screw interface, and reduced computed tomography and magnetic resonance imaging scatter and artifact. 相似文献
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Elena Antonova Veena Kumari Robin Morris Rozmin Halari A Anilkumar Ravi Mehrotra Tonmoy Sharma 《Neuropsychopharmacology》2005,58(6):457-467
BACKGROUND: Region of interest studies have identified a number of structure-cognition associations in schizophrenia and revealed alterations in structure-cognition relationship in this population. METHODS: We examined the relationship of structural brain alterations, identified using voxel-based morphometry, to cognitive deficits in 45 schizophrenia patients relative to 43 healthy control subjects and tested the hypothesis that structure-cognition relationship is altered in schizophrenia. RESULTS: Patients had smaller total brain, gray matter, and white matter volumes. Regional alterations were left-hemisphere specific, including: gray matter reduction of inferior frontal, lingual, and anterior superior temporal gyri; white matter reduction of posterior and occipital lobes; and gray matter increase of the putamen and the precuneus. Smaller whole brain and gray matter volumes were associated with lower premorbid intelligence quotient (IQ) and poorer performance on IQ-dependent cognitive measures in patients and to a similar extent in control subjects. Larger precuneus was associated with better immediate verbal memory in patients, whereas verbal and nonverbal memory were positively associated with inferior frontal gyrus volume in control subjects. Smaller occipital white matter volume was associated with slower information processing speed in patients but not in control subjects. CONCLUSIONS: Regional volume alterations are associated with specific cognitive deficits in schizophrenia. Some structure-cognition relationships differentiate this population from healthy control subjects. 相似文献
49.
Ravi Paluri Ashley Laursen Joseph Gaeta Shu Wang Andy Surinach Paul Cockrum 《The oncologist》2022,27(6):e518
BackgroundThe purpose of this study was to understand how the COVID-19 pandemic has affected health care patterns and outcomes for patients diagnosed with metastatic pancreatic ductal adenocarcinoma (mPDAC) in 2020 compared with those diagnosed with mPDAC in 2019.Patients and MethodsWe used the Flatiron Health database to identify adults diagnosed with mPDAC from March 1 to September 30, 2019 (pre-COVID-19 cohort) and March 1 to September 30, 2020 (post-COVID-19 cohort). Between-cohort comparisons included demographic and clinical characteristics and year-over-year data for diagnosis of mPDAC, newly treated patients, time to and types of first-line therapy, and adverse events (AEs) during first-line therapy. Overall survival (OS) and milestone survival rates were evaluated. Kaplan-Meier methods were used to assess OS.ResultsPre-COVID-19 (n = 923) and post-COVID-19 (n = 796) cohorts had similar baseline demographic characteristics. A smaller proportion of patients in the pre-COVID-19 cohort were initially diagnosed with stage IV disease versus the post-COVID-19 cohort (62.2% vs 69.7%). Between 2019 and 2020, there was a 13.8% decrease in diagnosis of mPDAC and a 13.0% decrease in newly treated patients. Median (interquartile range) times to first-line treatment were similar (21 [13-40] and 19 [12-32] days). Median OS (months) was significantly longer in the pre-COVID-19 cohort (8·4 [95% CI: 7·5, 9·0]) versus the post-COVID-19 cohort (6·1 [95% CI: 5·4, 6·9]; P < .001). Survival rates were higher in the pre-COVID-19 versus post-COVID-19 cohorts.ConclusionsDuring the pandemic, patients were initially diagnosed with PDAC at more advanced stages. While patients in both cohorts appeared to receive similar care, survival outcomes were adversely affected. 相似文献
50.