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991.
992.
Selective increase in TNF alpha permeation across the blood-spinal cord barrier after SCI 总被引:2,自引:0,他引:2
We generated a novel mouse model of spinal cord injury (SCI) by hemisection of the right L1 lumbar spinal cord, measured the permeability of the blood-spinal cord barrier (BSCB), and tested the hypothesis that tumor necrosis factor alpha (TNF alpha) penetrates the injured BSCB by an enhanced transport system. SCI produced stereotypical sensorimotor deficits resembling the classically described Brown-Seqúard syndrome. Disruption of the BSCB was reflected by increased spinal cord uptake of radiolabeled albumin from blood; this was transient (immediately after SCI) and confined to the lumbar spinal cord. By contrast, specific increase in the entry of TNF alpha was detected in brain, cervical, thoracic, and lumbar spinal cord at 1 week after SCI, in addition to its immediate and transient increase consistent with barrier disruption. Lack of a second peak of increase in the entry of IL1 beta further supported the specificity of the TNF alpha response. Moreover, enhanced uptake of radiolabeled TNF alpha was suppressed by excess non-radiolabeled TNF alpha, indicating competition of entry via the known transport system for TNF alpha. Therefore, upregulation of the transport system after SCI probably mediates the increased permeation of TNF alpha across the BSCB. Enhanced entry of TNF alpha at 1 week after SCI was concurrent with sensorimotor and gait improvement of the mouse. We conclude that SCI by lumbar hemisection activates the transport system for TNF alpha at the BBB and suggest that selective permeation of TNF alpha may facilitate functional recovery. 相似文献
993.
Lin SM Tsou MY Chan KH Yin YC Hsin ST Liao WW Mok MS Tsai SK 《Anesthesia and analgesia》2002,95(3):777-9, table of contents
IMPLICATIONS: We report a patient who developed myoclonic seizure in the postanesthesia care unit after thoracic laminectomy. Expeditious diagnostic evaluation of unrecognized dura tear during surgery must be instituted immediately to avoid untoward sequelae. Specific treatment in addition to supportive care is required if the diagnosis is to be clearly identified. 相似文献
994.
我国物理医学与康复专业相对年轻 ,但近年来都有了长足的进步 ,现总结如下。物理医学的重要部分是物理因子在治疗方面的使用与研究。近一年多有数百篇应用物理因子的文章发表 ,多数属于临床疾病的使用观察 ,但是也有不少同行注意进行临床和实验室的基础研究。在磁治疗方面 ,研究了不同磁场强度对人离体血液流变学的影响[1] ,不均匀磁场对小鼠血栓形成及血浆的影响[2 ] ,低频电磁场对人脐静脉内皮细胞增殖的影响[3 ] ,也有脱出原有范围 ,使用运动诱发电位的高强度 (1~ 2tesla)脉冲磁刺激于治疗上的研究 ,华中科大同济医学院同济医院使… 相似文献
995.
Chen WC McBride WH Iwamoto KS Barber CL Wang CC Oh YT Liao YP Hong JH de Vellis J Shau H 《Journal of neuroscience research》2002,70(6):794-798
Results of this study indicate a radioprotective effect of peroxiredoxin-I. Peroxiredoxin-I is an antioxidant that scavenges hydroperoxides, whereas reactive oxygen species are the main mediators of ionizing radiation toxicity. We hypothesized that peroxiredoxin-I might be induced by cellular exposure to radiation and act to protect them against its cytotoxic effects. Western blot and Northern blot analyses were used to assess peroxiredoxin-I protein and mRNA expression. Rat C6 glioma cells were engineered to overexpress sense or antisense human peroxiredoxin-I using retroviral vectors. Clonogenic cell survival was used to assess radiosensitivities of the engineered cells. Ionizing radiation induced peroxiredoxin-I protein and mRNA expression in human HT29 colon cancer and rat C6 glioma cells in a dose- and time-dependent manner over a 24 hr period. To determine the effect of peroxiredoxin-I on radiation responses, C6 glioma cells were engineered to overexpress sense or antisense human peroxiredoxin-I. In clonogenic assays, cells overexpressing peroxiredoxin-I were more radioresistant. Cells transduced with antisense peroxiredoxin-I were marginally more sensitive to radiation toxicity. Irradiation can induce peroxiredoxin-I expression, and the increased peroxiredoxin-I may protect cells from further radiation damage. These results suggest that protection by peroxiredoxin-I may play an important role in the survival of glioma and colon cancer cells in patients undergoing radiation therapy. 相似文献
996.
Papazisi L Silbart LK Frasca S Rood D Liao X Gladd M Javed MA Geary SJ 《Vaccine》2002,20(31-32):3709-3719
The aim of this study was to assess the efficacy of a modified live Mycoplasma gallisepticum vaccine (GT5) for the protection of chickens against infection and respiratory disease. GT5 was constructed by the reconstitution of the avirulent high passage R (R(high)) strain with the gene encoding the major cytadhesin GapA. GT5 expressed GapA on its surface yet retained the phenotypic characteristics of the parental R(high) strain. Birds vaccinated with GT5 were protected upon challenge with the virulent low passage R (R(low)) strain as evidenced by a complete absence of tracheal lesions 2 and 4 weeks post-challenge, in contrast to sham immunized/challenged control birds. Modest amounts of IgG, and little, if any secretory IgA or IgM anti-M. gallisepticum were found in tracheal washings following vaccination. However, copious amounts of specific IgA were found following challenge, especially in sham immunized birds. This suggests that the tracheal IgG elicited by GT5 vaccination may have been responsible for blocking the initial colonization of R(low), thereby resulting in protection. 相似文献
997.
Inhibition of 7,12-dimethylbenz[a]anthracene (DMBA)-induced oral carcinogenesis in hamsters by tea and curcumin 总被引:10,自引:0,他引:10
Li N Chen X Liao J Yang G Wang S Josephson Y Han C Chen J Huang MT Yang CS 《Carcinogenesis》2002,23(8):1307-1313
Tea is one of the most popular beverages consumed in the world. Curcumin, the major yellow pigment in turmeric, is used widely as a spice and food-coloring agent. In this study, we studied the effects of tea and curcumin on 7,12-dimethylbenz[a]anthracene (DMBA)-induced oral carcinogenesis in hamsters. DMBA solution (0.5% in mineral oil, 0.1 ml) was applied topically to the left cheek pouch of male Syrian golden hamsters 3 times/week for 6 weeks. Two days after the last treatment of DMBA, the animals received green tea (6 mg tea solids/ml) as drinking fluid, or 10 mmol curcumin applied topically 3 times/week, or the combination of green tea and curcumin treatment, or no treatment for 18 weeks. The combination of tea and curcumin significantly decreased the oral visible tumor incidence from 92.3% (24/26) to 69.2% (18/26) and the squamous cell carcinoma (SCC) incidence from 76.9% (20/26) to 42.3% (11/26). The combination of tea and curcumin also decreased the number of visible tumors and the tumor volume by 52.4 and 69.8%, as well as the numbers of SCC, dysplasic lesions and papillomas by 62.0, 37.5 and 48.7%, respectively. Green tea or curcumin treatment decreased the number of visible tumors by 35.1 or 39.6%, the tumor volume by 41.6 or 61.3% and the number of SCC by 53.3 or 51.3%, respectively. Green tea also decreased the number of dysplasic lesions. Curcumin also significantly decreased the SCC incidence. Tea and curcumin, singly or in combination, decreased the proliferation index in hyperplasia, dysplasia and papillomas. Only the combination treatment decreased the proliferation index in SCC. Tea alone and in combination with curcumin significantly increased the apoptotic index in dysplasia and SCC. Curcumin, alone and in combination with tea, significantly inhibited the angiogenesis in papilloma and SCC. The results suggested that green tea and curcumin had inhibitory effects against oral carcinogenesis at the post-initiation stage and such inhibition may be related to the suppression of cell proliferation, induction of apoptosis and inhibition of angiogenesis. 相似文献
998.
Neuroprotective effects of ginseng total saponin and ginsenosides Rb1 and Rg1 on spinal cord neurons in vitro 总被引:15,自引:0,他引:15
Spinal cord injury is a major cause of disability and results in many serious physical, psychological, and social difficulties. Numerous studies have shown that traumatic spinal cord injuries (SCI) lead to neuronal loss and axonal degeneration in and around the injury site that cause partial disability or complete paralysis. An important strategy in the treatment of SCI is to promote neuron survival and axon outgrowth, making possible the recovery of neural connections. Using an in vitro survival assay, we have identified ginsenosides Rb1 and Rg1, extracted from ginseng root (Panax ginseng C. A. Meyer), as efficient neuroprotective agents for spinal cord neurons. These compounds protect spinal neurons from excitotoxicity induced by glutamate and kainic acid, as well as oxidative stress induced by H(2)O(2). The neuroprotective effects are dose-dependent. The optimal doses are 20-40 microM for ginsenosides Rb1 and Rg1. The effects are specific for Rb1 and Rg1, since a third ginsenoside, Re, did not exhibit any activity. Ginseng has been used for thousands of years in the treatment of neurological disorders and other diseases in Asia. Ginsenosides Rb1 and Rg1 represent potentially effective therapeutic agents for spinal cord injuries. 相似文献
999.
Background: Granuloma gluteale infantum is a skin disorder of controversial etiology manifested clinically by oval reddish-purple
granulomatous nodules on the gluteal surfaces and groin areas of infants. Similar granulomas are noted in adults and the elderly
and are referred to as granuloma gluteale adultorum and diaper area granuloma of the aged, respectively. Occlusion from diapers,
paper napkins, plastic pants, detergents, starch, powder, halogenated steroids, candidal infection, and urine and feces are
postulated as possible etiologies. Objective: We report a case of a 40-year-old woman presenting with a 3-year history of
multiple, painful, closely set, red-purple, oval, smooth, firm papules and nodules in the genitocrural area. The development
of the lesions was associated with prolonged use of topical benzocaine. Histology of the lesions was consistent with granuloma
gluteale infantum. Gram stain and culture of representative tissue did not demonstrate bacterial or fungal organisms. The
lesions significantly improved with discontinuation of topical benzocaine. Patch testing of skin to determine allergic contact
hypersensitivity to benzocaine was negative. Conclusion: We propose that topical benzocaine preparations may play a role in
the pathogenesis of granuloma gluteale adultorum, independent of contact sensitization to benzocaine. 相似文献
1000.
Topical applications of caffeine or (-)-epigallocatechin gallate (EGCG) inhibit carcinogenesis and selectively increase apoptosis in UVB-induced skin tumors in mice 总被引:10,自引:0,他引:10 下载免费PDF全文
Lu YP Lou YR Xie JG Peng QY Liao J Yang CS Huang MT Conney AH 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(19):12455-12460
SKH-1 hairless mice were irradiated with ultraviolet B (UVB) twice weekly for 20 weeks. These tumor-free mice, which had a high risk of developing skin tumors during the next several months, were then treated topically with caffeine (6.2 micromol) or (-)-epigallocatechin gallate (EGCG; 6.5 micromol) once a day 5 days a week for 18 weeks in the absence of further treatment with UVB. Topical applications of caffeine to these mice decreased the number of nonmalignant and malignant skin tumors per mouse by 44% and 72%, respectively. Topical applications of EGCG decreased the number of nonmalignant and malignant tumors per mouse by 55% and 66%, respectively. Immunohistochemical analysis showed that topical applications of caffeine or EGCG increased apoptosis as measured by the number of caspase 3-positive cells in nonmalignant skin tumors by 87% or 72%, respectively, and in squamous cell carcinomas by 92% or 56%, respectively, but there was no effect on apoptosis in nontumor areas of the epidermis. Topical applications of caffeine or EGCG had a small inhibitory effect on proliferation in nonmalignant tumors as measured by BrdUrd labeling (16-22%), and there was also a similar, but nonsignificant, inhibitory effect on proliferation in malignant tumors. The results suggest a need for further studies to determine whether topical applications of caffeine or EGCG can inhibit sunlight-induced skin cancer in humans. 相似文献