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991.
In a three-week pelagic estuarine enclosure experiment, no effect concentrations (NEC) for tri-butyl-tin (TBT) were found in phytoplankton in the lower pico molar (pM) range as indicated by increased TBT tolerance, changes in taxonomic composition, decreased primary production and in the chlorophyll a (chl. a) concentration. Decreased primary production and chl.a concentrations were found only three days after addition of TBT. On the other hand, taxonomic changes and increased tolerance were found throughout the experiment, indicating a recovery of the ecosystem caused by adaptation of the phytoplankton in terms of structural changes. Induction of TBT tolerance is assumed to be evident of a direct toxic effect of TBT on the phytoplankton and the observed effects are thus not just attributable to indirect effect caused by direct effects on e.g. zooplankton. TBT concentrations in the lower pM range in coastal waters, such as open bays and estuaries, have been reported, indicating that natural phytoplankton could be affected by TBT in such areas. 相似文献
992.
Kai Wang Shile Zhang Bruz Marzolf Pamela Troisch Amy Brightman Zhiyuan Hu Leroy E. Hood David J. Galas 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(11):4402-4407
Drug-induced liver injury is a frequent side effect of many drugs, constitutes a significant threat to patient health and has an enormous economic impact on health care expenditures. Numerous efforts have been made to identify reliable and predictive markers to detect the early signs of drug-induced injury to the liver, one of the most vulnerable organs in the body. These studies have, however, not delivered any more informative candidates than the serum aminotransferase markers that have been available for ≈30 years. Using acetaminophen overdose-induced liver injury in the mouse as a model system, we have observed highly significant differences in the spectrum and levels of microRNAs in both liver tissues and in plasma between control and overdosed animals. Based on our survey of microRNA expression among normal tissues, some of the microRNAs, like messenger RNAs, display restricted tissue distributions. A number of elevated circulating microRNAs in plasma collected from acetaminophen-overdosed animals are highly expressed in the liver. We have demonstrated that specific microRNA species, such as mir-122 and mir-192, both are enriched in the liver tissue and exhibit dose- and exposure duration-dependent changes in the plasma that parallel serum aminotransferase levels and the histopathology of liver degeneration, but their changes can be detected significantly earlier. These findings suggest the potential of using specific circulating microRNAs as sensitive and informative biomarkers for drug-induced liver injury. 相似文献
993.
Lidocaine has been used in treatment of patients with refractory headache. Personal observations of neuropsychiatric toxicity in these patients led us to review our cases and the literature systematically for lidocaine side-effects, especially neuropsychiatric symptoms. In our series of 20 patients, side-effects were observed in all, the most frequent being neuropsychiatric (75%) and cardiological (50%). When reviewing published series on intravenous lidocaine use, reports of side-effects range from 0 to 100%, with neuropsychiatric symptoms being reported in 1.8–100%. Thirty-six case reports of lidocaine-induced psychiatric symptoms were also analysed. Psychiatric symptoms of toxicity were similar in most patients, despite their differing ages, pathologies, co-therapies and lidocaine dosages. In conclusion, lidocaine neuropsychiatric toxicity has a well-recognized stereotypical clinical presentation that is probably unrecognized in headache series. As lidocaine represents an emerging alternative therapy in headache, particularly in short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing, clinicians and patients should be aware of the extent of this problem. 相似文献
994.
《Nanotoxicology》2013,7(2):149-156
Because of their specific properties (mechanical, electrical, etc), carbon nanotubes (CNTs) are being assessed for inclusion in many manufactured products. Due to their massive production and number of potential applications, the impact of CNTs on the environment must be taken into consideration. The present investigation evaluates the ecotoxic potential of CNTs in the amphibian larvae (Ambystoma mexicanum). Acute toxicity and genotoxicity were analysed after 12 days of exposure in laboratory conditions. The genotoxic effects were analysed by scoring the micronucleated erythrocytes in the circulating blood of the larvae according to the French standard micronucleus assay. The results obtained in the present study demonstrated that CNTs are neither acutely toxic nor genotoxic to larvae whatever the CNTs concentration in the water, although black masses of CNTs were observed inside the gut. In the increasing economical context of CNTs, complementary studies must be undertaken, especially including mechanistic and environmental investigations. 相似文献
995.
Pilar Sánchez Henarejos Silverio Ros Martínez Gema R. Marín Zafra José L. Alonso Romero Agustín Navarrete Montoya 《Clinical & translational oncology》2009,11(7):486-487
Pegylated liposomal doxorubicin (PLD) is a drug whose use is increasingly common. It has been associated with a lower rate
of haematologic and cardiac side effects than its nonencapsulated form. However, mucocutaneous toxicity is quite frequent
and can be severe. Here we provide a case report of a patient who developed an intertrigolike eruption during treatment with
PLD. 相似文献
996.
铁离子对大脑毒性的研究进展 总被引:1,自引:0,他引:1
铁离子广泛存在于脑组织各部位,基底神经节含量最高,红核、黑质和齿状核较多,大脑皮质和小脑相对较少。铁毒性作用主要基于芬顿化学作用,铁与活性氧中间物反应,可产生高反应的自由基。脑内不同的细胞对铁超载及血红蛋白的防御反应,都可引起对神经元的毒性作用。自由铁通过产生的自由基对脑有高度的毒性作用,然而,在脑损伤和脑出血中铁的浓度是否是导致神经元损伤和死亡的必然因素,血液是否是促使神经元死亡的原因尚不是很清楚。 相似文献
997.
998.
999.
Cyrus Chargari Krassen M. KirovMarc A. Bollet Nicolas MagnéLionel Védrine Serge CremadesPhilippe Beuzeboc Alain FourquetYoulia M. Kirova 《Cancer treatment reviews》2011,37(4):321-330
When focusing on heart disease, most available studies split the two different parts of the adjuvant treatment, i.e., systemic therapies and radiation therapy, making it difficult to implement efficient strategies for preventing treatment-induced cardiac toxicity. This paper reviews the current understanding of treatments-induced cardiac toxicity in a global approach. Many factors should be considered when assessing the cardiac hazard. Treatment-related risk factors include heart dose exposure, chemotherapy, targeted agents such as HER2 inhibitors, but also endocrine agents, or anesthetic procedure. Patients’ characteristics should also be taken into account. Age, menopausal status, stress, previous history of cardiac disease, genetic profile, and body mass index could all impact on cardiac function after adjuvant therapies. Cardiac toxicity should not be analyzed as the consequence of a specific therapy, but should be considered as the result of additive or supra-additive toxicities. By this way, it will be possible to implement new strategies for preventing treatment-induced cardiac toxicity. 相似文献
1000.