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991.
K Campbell 《Leukemia》2005,19(9):1704-1705
992.
Im Hinblick auf die eindrucksvollen Remissionsraten, die in den letzten Jahren in der Therapie des Hodgkin-Lymphoms erzielt wurden, gewinnen die therapieinduzierten Spätkomplikationen einen immer größeren Stellenwert. In Abhängigkeit von Stadium und Risikofaktoren können nach der Primärtherapie mittlerweile Langzeitremissionen von über 80% erzielt werden. Demzufolge hat gerade das Überleben junger Patienten im reproduktiven Alter zugenommen, weshalb genaue Analysen therapieinduzierter Spätfolgen immer mehr in den Vordergrund treten. Zu den wichtigsten therapieinduzierten Akut- und Spättoxizitäten zählen Infertilität, kardiale, pulmonale oder thyroidale Funktionsstörungen und insbesondere Sekundärneoplasien, die zu einer signifikanten Mortalität beitragen. Außerdem kann ein noch lange Zeit nach der Therapie anhaltendes Fatiguesyndrom auftreten. Die Therapiestrategien aktueller klinischer Studien zielen daher insbesondere auf eine Reduktion von therapiebedingten Spätfolgen bei gleichzeitiger Beibehaltung der guten Tumorkontrolle. 相似文献
993.
G. B. Slepchenko L. S. Anisimova V. F. Slipchenko E. V. Mikheeva N. P. Pikula 《Pharmaceutical Chemistry Journal》2005,39(3):166-168
Rapid voltammetric procedures for the determination of water-soluble vitamins C, B1, and B2, fat-soluble vitamin E (α-tocopherol acetate), and quercetin in bioactive food additives have been developed. The systematic error (i.e., correctness) of the proposed procedures was evaluated using certified reference materials and the additive recovery tests, which gave the following limiting metrological characteristics: relative error, 25 %; reproducibility, 28 %; convergence, 22 %. The full analysis time (with sample preparation) did not exceed 2 hours. Voltammetric determinations under optimum conditions can be performed in the automated regime controlled by a computer according to the specially developed software.__________Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 3, pp. 54 – 56, March, 2005. 相似文献
994.
L. A. Trukhacheva V. I. Levina A. P. Arzamastsev N. B. Grigor'ev V. G. Granik 《Pharmaceutical Chemistry Journal》2005,39(6):296-299
The kinetics of alkaline hydrolysis of N-(5-nitro-2-thiazolyl)-2-thiophenylcarboxamide (tenonitrozole or atrican) has been studied by photometric and polarographic
techniques, and the thermodynamic parameters in the intermediate state of this process were determined. A mechanism explaining
the nitric oxide (NO) production during the hydrolytic decomposition of tenonitrozole is proposed. It is suggested that the
antiprotozoal and antimicrobial activity of this drug under anaerobic conditions is related to the formation of nitro radical
anions and NO. Under aerobic and microaerophilic conditions, the hydrolysis of tenonitrozole may lead to the formation of
a peroxynitrite anion, which is a strong cytotoxic agent.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 6, pp. 15 – 18, June, 2005. 相似文献
995.
R Tootla G Kotru M A Connolly M S Duggal K J Toumba 《European journal of paediatric dentistry》2005,6(3):139-143
AIM: The purpose of this pilot study was to identify the subsurface enamel demineralising potential of two possible acidogenic lactose-based powders and their corresponding generic pump inhalers. METHODS: Ten healthy non-asthmatic adults participated in a 5- leg randomised crossover study including a 10% sucrose control. A twice-daily 400 microg dose of inhaler was applied in vitro to a demineralised enamel slab on the buccal flange of a mandibular removable appliance before in situ placement for 14 days each. Lesion parameters were determined using transverse microradiography and digitised image analysis. RESULTS: Minimal demineralisation occurred with sucrose, both pump and one powder inhaler. The remaining powder was associated with remineralisation (p = 0.29). Overall, mean lesion depth increased (p = 0.12). CONCLUSION: Asthma inhalers failed to demonstrate a significant acidogenic/cariogenic effect. 相似文献
996.
997.
A case of esthesioneuroblastoma with an unusual clinical and radiographic presentation is reported. The presenting symptoms as well as the computed tomographic examination were compatible with a primary intracranial mass. 相似文献
998.
999.
An unusual, elongated, refractile cell morphology was observed in keratinocytes cultured from three patients with non-lethalis forms of junctional epidermolysis bullosa (JEB). To determine whether these changes might be related to altered cell adhesion, keratinocyte strains established from one patient were examined for adhesive, structural, and functional characteristics. JEB keratinocytes expressed keratin tonofilaments, as determined by staining with AE1 monoclonal antibodies and direct observation of tonofilaments by electron microscopy. JEB keratinocytes showed diminished cell-substratum adhesions, judged by interference reflection microscopy. Areas of diminished cell-substratum adhesion corresponded to F-actin-rich cell adhesions (focal adhesions) and not to cellular areas that abundantly express hemidesmosomal antigens. Analysis of cell-substratum adhesion by electron microscopy revealed extensive areas of cell-substratum separation in JEB keratinocytes that were not present in normal keratinocytes maintained in serum-free medium. Normal keratinocytes displayed numerous regions of focal contact between the ventral plasma membrane and the culture substratum, but these structures were not seen in JEB keratinocytes. Bundled actin filaments (stress fibers) were greatly diminished in expected regions of cell-substratum adhesion in JEB keratinocytes and, instead, displayed disorganized individual filaments. The growth rate of JEB keratinocytes was quite slow in culture, with a population doubling time of 2.7 d versus 1.5 d for normal keratinocytes under identical conditions. JEB keratinocytes also displayed a reduced ability to aggregate into colonies upon exposure to medium with increased extracellular calcium. JEB keratinocytes thus display adhesive, structural, and functional abnormalities that suggest this cell type may be central to the pathogenesis of junctional epidermolysis bullosa. Study of affected keratinocytes could be important to characterize associated molecular pathologies. 相似文献
1000.
Magnetic resonance imaging in planning limb-salvage surgery for primary malignant tumors of bone 总被引:4,自引:0,他引:4
M Sundaram M H McGuire D R Herbold M K Wolverson E Heiberg 《The Journal of bone and joint surgery. American volume》1986,68(6):809-819
In defining the linear extent of a malignant tumor in a long bone, radiographs, computerized tomography, and scintigraphy are routinely employed, especially when non-ablative surgery is being considered. The drawbacks of these modalities in defining the true intracompartmental extent of disease within a bone can largely be overcome with the use of magnetic resonance imaging. We did a prospective analysis of magnetic resonance imaging in sixteen consecutive patients with a primary malignant tumor of a long bone, and it showed that this modality has clinical promise of being more precise than the other modalities in defining the true proximal and distal extent of a tumor in a long bone. Coronal images permit easier planning of surgical techniques for salvage of a limb using an allograft than do a multiplicity of transverse images. 相似文献