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81.
G Malm K Teäzr Fahnehjelm S Wiklund M-L Engman SA Ivarsson K Petersson B Evengård 《Acta paediatrica (Oslo, Norway : 1992)》1999,88(6):667-670
The aim of this prospective study was to define the incidence of congenital toxoplasmosis in Sweden. Blood eluates collected on filter papers, Guthrie cards, from 40978 newborn babies were analysed for specific immunoglobulin M (IgM) and IgG antitoxoplasma antibodies. This is a preliminary report of three children with congenital toxoplasmosis, defined by the occurrence of antitoxoplasma-specific IgM antibodies. Two children were asymptomatic at birth. They were both normally developed at the age of 12 and 15 months, respectively. The third child had unidentified but uncomplicated symptoms of infection in the neonatal period. As a result of the screening congenital toxoplasmosis was confirmed and treatment instituted. Microphthalmus and peripheral chorioretinitis were detected in one eye. In spite of the chemotherapeutic treatment he developed hydrocephalus needing neurosurgical intervention at the age of 3 months. His development at 14 months was normal. The incidence in Sweden of congenital toxoplasmosis detected by specific IgM antitoxoplasma antibodies in blood from filter papers is less than 1:10000. 相似文献
82.
Peripheral nerve disorders may be classified into compressive or entrapment neuropathies and non‐compressive neuropathies. Muscle denervation recognized on MRI may be a useful sign in the diagnosis of peripheral nerve disorders. Acute or subacute denervation results in prolonged T2 relaxation time, producing increased signal in skeletal muscle on short tau inversion‐recovery and fat‐suppressed T2‐weighted images. Chronic denervation produces fatty atrophy of skeletal muscles, resulting in increased muscle signal on T1‐weighted images. This review will outline and illustrate the various ways that muscle denervation as seen on MRI may assist in the diagnosis and localization of peripheral nerve disorders. 相似文献
83.
Dewan SA Majid 《Clinical and experimental pharmacology & physiology》2007,34(9):905-905
84.
ER Brown KA Charles SA Hoare RL Rye DI Jodrell RE Aird R Vora U Prabhakar M Nakada RE Corringham M DeWitte C Sturgeon D Propper FR Balkwill JF Smyth 《Annals of oncology》2008,19(7):1340-1346
BACKGROUND: Tumour necrosis factor-alpha (TNF-alpha) is an important regulator of the chronic inflammation contributing to tumour progression. Infliximab, an anti-TNF-alpha monoclonal antibody was investigated in this trial of patients with advanced cancer. The primary objectives were to determine the safety profile and biological response of infliximab in a cancer population. Clinical response was a secondary objective. PATIENTS AND METHODS: Forty-one patients received infliximab at 5 mg/kg (n = 21) or 10 mg/kg (n = 20) i.v. at 0 and 2 weeks and then every 4 weeks. Post-treatment samples were measured for changes in plasma and serum TNF-alpha, CCL2, IL-6 and C-reactive protein (CRP). RESULTS: Infliximab was well tolerated with no dose-limiting toxic effects. At both doses of infliximab, neutralisation of serum TNF-alpha was observed after 1 h while plasma CCL2, IL-6 and serum CRP were decreased 24 and 48 h following infliximab administration. Seven patients experienced disease stablisation (range 10-50+ weeks). There was no evidence of disease acceleration in any patient. CONCLUSIONS: Infliximab treatment was safe and well tolerated in patients with advanced cancer. There was evidence of biological activity with baseline TNF-alpha and CCL2 being correlated with infliximab response. 相似文献
85.
实验动物资源是国家生命科学研究的重要科技资源。实验动物资源的共享和充分利用是生物科技创新的基础和保障。有效的共享机制和合理的共享方式是实现实验动物资源共享和充分利用的重要保障,是规范实验动物资源共享行为和确保共享安全的迫切需要。 相似文献
86.
A Ohlsson SA Calvert M Hosking AT Shennan 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(10):751-756
This randomized controlled trial was designed to answer the question: does administration of dexamethasone to neonates with bronchopulmonary dysplasia decrease the need for assisted ventilation? Twenty-five infants with a birth weight < 1501 g, requiring mechanical ventilation and FiO2 of ± 0.30 at 21-35 days of age, were randomized to treatment with iv dexamethasone or to sham injections for 12 days. The primary outcome criterion was extubation within seven days after study entry. Treatment (n= 12) and control (n= 13) groups were well matched at entry. Dexamethasone facilitated weaning from assisted ventilation (p= 0.0154). There was no increased incidence of infection. Dexamethasone treatment resulted in a significant increase in glucosuria (p= 0.0002) and in systolic blood pressure (p= 0.0034). There was a significant decrease in heart rate (p= 0.0001) and a significant weight loss (p= 0.0002) following dexamethasone treatment. Dexamethasone treatment facilitated weaning from assisted ventilation but several systemic effects were noted that deserve further evaluation before dexamethasone becomes routine treatment. 相似文献
87.
Effects of positive and negative pressure ventilation on cerebral blood volume of newborn infants 总被引:3,自引:0,他引:3
KS Palmer SA Spencer YABD Wickramasinghe T Wright DP Southall P Rolfe 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(2):132-139
The effects of intermittent positive airway and continuous negative extrathoracic pressure ventilation on cerebral blood volume in preterm infants were studied using near infrared spectroscopy. In 12 infants continuous negative extrathoracic pressure caused a median decrease in cerebral blood volume of 0.14ml/100ml brain (95% confidence intervals (CI) 0.035–0.280) compared with no respiratory support. Oxygenated and deoxygenated haemoglobin also decreased, implying increased venous drainage as the main effect. In 17 infants intermittent positive pressure ventilation also caused a median reduction in cerebral blood volume of 0.06 ml/100 ml brain (95% CI 0.010–0.115) compared with endotracheal positive airway pressure. Deoxygenated haemoglobin increased by 0.07 ml/100 ml brain (95% CI 0.010–0.100) while oxygenated haemoglobin decreased by O.lOml/lOOml brain (95% CI 0.005–0.175). The increase in deoxygenated haemoglobin implies decreased venous drainage and the decrease in oxygenated haemoglobin implies that other factors may also be significant. Heart rate, blood pressure and oxygen saturation were monitored continuously and remained stable. 相似文献
88.
Benzo[b]fluoranthene: tumorigenicity in strain A/J mouse lungs, DNA adducts and mutations in the Ki-ras oncogene 总被引:1,自引:0,他引:1
Mass Marc J.; Abu-Shakra Amal; Roop Barbara C.; Nelson Garret; Galati Anthony J.; Stoner Gary D.; Nesnow Stephen; Ross Jeffrey A. 《Carcinogenesis》1996,17(8):1701-1704
The polycyclic aromatic hydrocarbon benzo[b]fluoranthene (B[b]F)is a pervasive constituent of environmental combustion products.We sought to examine the lung tumorigenic activity of B[b]Fin strain A/J mice, to study the relationship between formationand decay of B[b]F-DNA adducts and to examine mutations in theKi-ras proto-oncogene in DNA from B[b]F-induced tumors. Micewere given i.p. injections of 0, 10, 50, 100 or 200 mg/kg bodywt and lung adenomas were scored after 8 months. B[b]F inducedsignificant numbers of mouse lung adenomas in a dose-relatedfashion, with the highest dose (200 mg/kg) yielding 6.95 adenomas/mouse, with 100% of the mice exhibiting an adenoma. In micegiven tricaprylin, the vehicle control, there were 0.60 adenomas/mouse,with 55% of the mice exhibiting an adenoma. Based on dose, B[b]Fwas less active than benzo[ 相似文献
89.
Galati G Fiori E De Cesare A Bononi M Sammartino F Tiziano G Cosenza M Barbarosos A Bolognese A 《Il Giornale di chirurgia》2002,23(3):85-87
The Authors have reported a case of retroperitoneal leiomyosarcoma. The retroperitoneal localization is quite unusual and early diagnosis is difficult. Only surgery operation and radio-chemotherapy can improve the prognosis. Tumor size is the major prognostic factor. 相似文献
90.
The introduction includes a literature review of DNA reactive species and DNA adduct formation that results from aromatic amine N-oxidation catalyzed by hepatic cytochrome P450 vs. that catalyzed by nonhepatic peroxidases. Experimental evidence is then described for a novel oxidative stress mechanism involving prooxidant N-cation radical formation by both oxidases, which is proposed as a contributing mechanism for aromatic amine induced cytotoxicity and carcinogenesis. Aromatic amine N-cation radicals formed by peroxidases were found to cooxidize GSH or NADH and form reactive oxygen species. The latter could explain the reported DNA oxidative damage found in vivo following methylaminoazobenzene administration [Hirano et al. Analyses of Oxidative DNA Damage and Its Repair Activity in the Livers of 3'-Methyl-4-dimethylaminoazobenzene-Treated Rodents. Jpn. J. Cancer Res. 2000, 91, 681-685]. It was also found that the prooxidant activity of the aromatic amine increased as its redox potential, i.e., ease of oxidation decreased with o-anisidine and aminofluorene being the most effective at forming reactive oxygen species. This suggests that the rate-limiting step in the cooxidation is the rate of arylamine oxidation by the peroxidase. Incubation of hepatocytes with aromatic amines caused a decrease in the mitochondrial membrane potential before cytotoxicity ensued. The CYP1A2-induced hepatocytes isolated from 3-methylcholanthrene administered rats were much more susceptible to some arylamines and were protected by CYP1A2 inhibitors. Hepatocyte GSH was also depleted by all arylamines tested and extensive GSH oxidation occurred with o-anisidine and aminofluorene, which was prevented by CYP1A2 inhibitors. This suggests that in intact hepatocytes CYP1A2 may also catalyze a one-electron oxidation of some arylamines to form prooxidant cation radicals, which cooxidize GSH to form the reactive oxygen species. 相似文献