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101.
Claudiu Mărgăritescu Daniel Pirici Alin Stîngă Cristiana Simionescu Marius Raica Laurentiu Mogoantă Alex Stepan Domenico Ribatti 《Clinical and experimental medicine》2010,10(4):209-214
Angiogenesis is involved in tumor progression of oral squamous cell carcinoma (OSCC). In this study, we have investigated
by immunohistochemistry vascular endothelial growth factor (VEGF) expression in tumor cells and we have correlated VEGF expression
to microvessel area, evaluated by using CD105 as a marker of endothelial cells, in bioptic specimens of 54 human OSCC. Results
demonstrated that VEGF is highly expressed in OSCC tumor specimens when compared to pre-neoplastic and normal tissues, without
differences between the edge and inside the tumor. Moreover, VEGF expression is reduced in poor differentiated OSCC tumors
when compared to moderate and good differentiated forms, and tumor microvessel area is higher in tumors when compared to pre-neoplastic
lesions and normal tissues. Finally, VEGF and CD105 may be considered as reliable markers of tumor angiogenesis and progression
in OSCC, even if we did not demonstrate any correlation between VEGF expression, tumor microvascular area, clinical stage,
and lymph node status. 相似文献
102.
Genotype-phenotype relationship in human ATP6i-dependent autosomal recessive osteopetrosis 总被引:5,自引:0,他引:5 下载免费PDF全文
Taranta A Migliaccio S Recchia I Caniglia M Luciani M De Rossi G Dionisi-Vici C Pinto RM Francalanci P Boldrini R Lanino E Dini G Morreale G Ralston SH Villa A Vezzoni P Del Principe D Cassiani F Palumbo G Teti A 《The American journal of pathology》2003,162(1):57-68
Autosomal-recessive osteopetrosis is a severe genetic disease caused by osteoclast failure. Approximately 50% of the patients harbor mutations of the ATP6i gene, encoding for the osteoclast-specific a3 subunit of V-ATPase. We found inactivating ATP6i mutations in four patients, and three of these were novel. Patients shared macrocephaly, growth retardation and optic nerve alteration, osteosclerotic and endobone patterns, and high alkaline phosphatase and parathyroid hormone levels. Bone biopsies revealed primary spongiosa lined with active osteoblasts and high numbers of tartrate-resistant acid phosphatase (TRAP)-positive, a3 subunit-negative, morphologically unremarkable osteoclasts, some of which located in shallow Howship lacunae. Scarce hematopoietic cells and abundant fibrous tissue containing TRAP-positive putative osteoclast precursors were noted. In vitro osteoclasts were a3-negative, morphologically normal, with prominent clear zones and actin rings, and TRAP activity more elevated than in control patients. Podosomes, alphaVbeta3 receptor, c-Src, and PYK2 were unremarkable. Consistent with the finding in the bone biopsies, these cells excavated pits faintly stained with toluidine blue, indicating inefficient bone resorption. Bone marrow transplantation was successful in all patients, and posttransplant osteoclasts showed rescue of a3 subunit immunoreactivity. 相似文献
103.
104.
Draper N Bui M Boulware DC Lloyd M Chiappori AA Pledger WJ Coppola D 《Human pathology》2008,39(12):1784-1791
Gastrointestinal stromal tumors, the most common mesenchymal tumors of the gastrointestinal tract, are characterized by strong expression of c-Kit protein. Recently, it has been shown that gastrointestinal stromal tumors may also contain alterations of genes involved in the regulation of cell cycle. In this study, we evaluate the prevalence and clinical significance of cyclin D1 and D3, Ki-67, p27, and retinoblastoma protein expression in a group of 50 human gastrointestinal stromal tumors selected from the files of the Moffitt Cancer Center. Tissue sections from each case were subjected to immunostaining using the avidin-biotin complex method. Cyclin D1 nuclear positivity was detected in 21 of 50 (42%) and cyclin D3 in 24 of 50 (48%) cases. p27 high immunoreactivity and negative or decreased retinoblastoma protein expression were identified in 33 of 50 (66%) gastrointestinal stromal tumors. In 19 of 50 (38%) tumors, Ki-67 had high labeling index. Direct correlation was observed between cyclin D3 and p27 expression (P < .0001), and between cyclin D1 and retinoblastoma protein (P = .03). Coexpression of cyclin D3 and p27 was demonstrated by immunofluorescence. The p27 protein expression inversely correlated with tumor size (P = .004), but was not correlated with tumor grade (P = .12). Ki-67 directly correlated with both tumor size (P = .03) and tumor grade (P = .008). We report a direct correlation between cyclin D3 and p27 expression in gastrointestinal stromal tumors. Additional alterations in cyclin D1, Ki-67, and retinoblastoma protein expression indicate a disregulated cell cycle in these tumors. 相似文献
105.
Roberta Cocchiara Giovanna Di Trapani Antonina Azzolina Domenico Geraci 《Journal of immunoassay & immunochemistry》2013,34(4):337-352
Abstract An ELISA assay is described for the measurement of the smIgG. The method is based on the detection of cell-smIgG directly on the same microplate used for the culture. The cells, preincubated at 37°C for one hour, were cultured in the presence of S-ConA and serum-free medium for two days. Using this strategy, the background noise due to non specific adsorbtion of IgG to plastic wells and cytophilic antibodies was eliminated. The cells in the presence of S-ConA and serum-free medium adhered to the plastic wells, and the cell-smIgG were detected using an anti-human IgG covalently linked to alkaline phosphatase or its F(ab')2 fragment. The possibility of measuring the modulation of the expression of the cell-smIgG without any additional manipulation is stressed. 相似文献
106.
Maria Luisa Torre Giuseppina T. Russo Marta Ragonese Annalisa Giandalia Ernesto De Menis Giorgio Arnaldi Angela Alibrandi Carmelo Buda Giovanni Romanello Elisabetta L. Romeo Domenico Cucinotta Francesco Trimarchi Salvatore Cannavo 《Pituitary》2014,17(3):257-266
Background
Acromegalic patients have a higher risk of developing colorectal tumours (CRT). The common C677T polymorphism in methylenetetrahydrofolate reductase (MTHFR) gene is a well-documented CRT risk factor in the general population, but its role in acromegaly has never been examined.Purpose
We investigated the influence of MTHFR C677T polymorphism, folate status and other lifestyle, nutritional and disease-specific variables on CRT risk in acromegaly.Methods
Clinical data were collected from 115 acromegalic patients (25 with active disease) who underwent a complete colonoscopy. C677T MTHFR genotype, homocysteine, vitamin B12, insulin growth factor and insulin levels, as well as metabolic variables were evaluated.Results
Colorectal tumours were identified in 51 patients (3 adenocarcinomas). MTHFR C677T distribution was in the Hardy–Weinberg equilibrium and similar in patients with or without CRT. There was a correlation between patients with TT genotype and CRT occurrence (Spearman’s test: P = 0.03), with an Odds Ratio (OR) of 1.32 (95 % CI 0.522–3.362, P NS). A folate–MTHFR genotype interaction on CRT risk was found (P = 0.037): in the lower folate subgroup, TT patients showed a 2.4 higher OR for CRT (95 % CI 0.484–11.891; P NS) than C-allele carriers. Smoking (P = 0.007), increased HbA1c levels (P = 0.021), dyslipidaemia (P = 0.049), acromegaly control (P = 0.057), and folate–MTHFR genotype interaction (P = 0.088) were associated with CRT at multivariate analysis.Conclusions
In this cohort of acromegalic patients, CRT risk is increased in 677TT MTHFR patients with low plasma folate levels. Smoking, high HbA1c levels, dyslipidaemia and disease activity were also associated with increased CRT risk. 相似文献107.
Manuel Cappellari Giuseppe Moretto Nicola Micheletti Francesco Donato Giampaolo Tomelleri Giosuè Gulli Monica Carletti Giovanna Maddalena Squintani Tiziano Zanoni Sarah Ottaviani Silvia Romito Giorgio Tommasi Anna Maria Musso Luciano Deotto Giuseppe Gambina Domenico Sergio Zimatore Paolo Bovi 《Journal of thrombosis and thrombolysis》2014,37(4):549-556
According to current European Alteplase license, therapeutic-window for intravenous (IV) thrombolysis in acute ischemic stroke has recently been extended to 4.5 h after symptoms onset. However, due to numerous contraindications, the portion of patients eligible for treatment still remains limited. Early neurological status after thrombolysis could identify more faithfully the impact of off-label Alteplase use that long-term functional outcome. We aimed to identify the impact of off-label thrombolysis and each off-label criterion on early clinical outcomes compared with the current European Alteplase license. We conducted an analysis on prospectively collected data of 500 consecutive thrombolysed patients. The primary outcome measures included major neurological improvement (NIHSS score decrease of ≤8 points from baseline or NIHSS score of 0) and neurological deterioration (NIHSS score increase of ≥4 points from baseline or death) at 24 h. We estimated the independent effect of off-label thrombolysis and each off-label criterion by calculating the odds ratio (OR) with 2-sided 95 % confidence interval (CI) for each outcome measure. As the reference, we used patients fully adhering to the current European Alteplase license. 237 (47.4 %) patients were treated with IV thrombolysis beyond the current European Alteplase license. We did not find significant differences between off- and on-label thrombolysis on early clinical outcomes. No off-label criteria were associated with decreased rate of major neurological improvement compared with on-label thrombolysis. History of stroke and concomitant diabetes was the only off-label criterion associated with increased rate of neurological deterioration (OR 5.84, 95 % CI 1.61–21.19; p = 0.024). Off-label thrombolysis may be less effective at 24 h than on-label Alteplase use in patients with previous stroke and concomitant diabetes. Instead, the impact of other off-label criteria on early clinical outcomes was not different compared with current European Alteplase license. 相似文献
108.
Allen NE Key TJ Dossus L Rinaldi S Cust A Lukanova A Peeters PH Onland-Moret NC Lahmann PH Berrino F Panico S Larrañaga N Pera G Tormo MJ Sánchez MJ Ramón Quirós J Ardanaz E Tjønneland A Olsen A Chang-Claude J Linseisen J Schulz M Boeing H Lundin E Palli D Overvad K Clavel-Chapelon F Boutron-Ruault MC Bingham S Khaw KT Bueno-de-Mesquita HB Trichopoulou A Trichopoulos D Naska A Tumino R Riboli E Kaaks R 《Endocrine-related cancer》2008,15(2):485-497
Epidemiological data show that reproductive and hormonal factors are involved in the etiology of endometrial cancer, but there is little data on the association with endogenous sex hormone levels. We analyzed the association between prediagnostic serum concentrations of sex steroids and endometrial cancer risk in the European Prospective Investigation into Cancer and Nutrition using a nested case-control design of 247 incident endometrial cancer cases and 481 controls, matched on center, menopausal status, age, variables relating to blood collection, and, for premenopausal women, phase of menstrual cycle. Using conditional regression analysis, endometrial cancer risk among postmenopausal women was positively associated with increasing levels of total testosterone, free testosterone, estrone, total estradiol, and free estradiol. The odds ratios (ORs) for the highest versus lowest tertile were 2.66 (95% confidence interval (CI) 1.50-4.72; P=0.002 for a continuous linear trend) for estrone, 2.07 (95% CI 1.20-3.60; P=0.001) for estradiol, and 1.66 (95% CI 0.98-2.82; P=0.001) for free estradiol. For total and free testosterone, ORs for the highest versus lowest tertile were 1.44 (95% CI 0.88-2.36; P=0.05) and 2.05 (95% CI 1.23-3.42; P=0.005) respectively. Androstenedione and dehydroepiandrosterone sulfate were not associated with risk. Sex hormone-binding globulin was significantly inversely associated with risk (OR for the highest versus lowest tertile was 0.57, 95% CI 0.34-0.95; P=0.004). In premenopausal women, serum sex hormone concentrations were not clearly associated with endometrial cancer risk, but numbers were too small to draw firm conclusions. In conclusion, relatively high blood concentrations of estrogens and free testosterone are associated with an increased endometrial cancer risk in postmenopausal women. 相似文献
109.
110.
Domenico Benvenuto Marta Giovanetti Alessandra Ciccozzi Silvia Spoto Silvia Angeletti Massimo Ciccozzi 《Journal of medical virology》2020,92(4):455-459
There is a worldwide concern about the new coronavirus 2019-nCoV as a global public health threat. In this article, we provide a preliminary evolutionary and molecular epidemiological analysis of this new virus. A phylogenetic tree has been built using the 15 available whole genome sequences of 2019-nCoV, 12 whole genome sequences of 2019-nCoV, and 12 highly similar whole genome sequences available in gene bank (five from the severe acute respiratory syndrome, two from Middle East respiratory syndrome, and five from bat SARS-like coronavirus). Fast unconstrained Bayesian approximation analysis shows that the nucleocapsid and the spike glycoprotein have some sites under positive pressure, whereas homology modeling revealed some molecular and structural differences between the viruses. The phylogenetic tree showed that 2019-nCoV significantly clustered with bat SARS-like coronavirus sequence isolated in 2015, whereas structural analysis revealed mutation in Spike Glycoprotein and nucleocapsid protein. From these results, the new 2019-nCoV is distinct from SARS virus, probably trasmitted from bats after mutation conferring ability to infect humans. 相似文献