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91.
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Pradhan M Behari S Kalra SK Ojha P Agarwal S Jain VK 《Journal of neurosurgery. Spine》2007,7(6):623-630
OBJECT: Genetic mechanisms of atlantoaxial dislocation (AAD) have not previously been elucidated. The authors studied association of polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene, which encodes enzymes of the folate pathway (implicated in causation of neural tube defects [NTDs]), in patients with AAD. METHODS: Molecular analysis of MTHFR polymorphisms (677C-->T, cytosine to thymine and, 1298A-->C, adenine to cytosine, substitutions) was carried out using polymerase chain reaction and restriction enzyme digestion in 75 consecutive patients with AAD and in their reducible (nine patients, 12%) and irreducible (66 patients, 88%) subgroups. Controls were 60 age- and sex-matched patients of the same ethnicity. Comparisons of genotype and allele frequencies were performed using a chi-square test (with significance at p < 0.05). RESULTS: The CT genotype frequency of MTHFR 677C-->T polymorphism was significantly increased in the full group of patients with AAD (odds ratio [OR] 3.00, 95% confidence interval [CI] 1.28-7.14, p = 0.005) as well as in the irreducible subgroup (OR 2.81, 95% CI 1.17-6.86, p = 0.01). The frequency of T alleles was also higher in the AAD group (25.3%) than in controls (15%). The comparison of the combined frequency of CT and TT genotypes with the frequency of the CC genotype again showed significant association in AAD (OR 2.63, 95% CI 1.98-5.90, p = 0.009) and the irreducible (OR 2.5, 95% CI 1.1-5.74, p = 0.016) subgroup. There was, however, no significant association of MTHFR 1298A-->C polymorphism with AAD. CONCLUSIONS: Both MTHFR 677C-->T polymorphism and higher T allele frequency have significant associations with AAD, especially the irreducible variety. Perhaps adequate supplementation of periconceptional folic acid to circumvent effects of this missense mutation (as is done for prevention of NTDs) would reduce the incidence of AAD. 相似文献
94.
注射用双黄连与几种抗生素联合体外抑菌活性的研究 总被引:11,自引:0,他引:11
目的:探讨注射用双黄连与抗生素联合使用的临床意义。方法:参考中国药典抗生素微生物检定法,测定注射用双黄连与头孢拉定等6种抗生素配伍使用后对金葡菌及克雷白氏肺炎杆菌的抑菌圈直径的变化。结果:注射用双黄连与氨苄青霉素、普鲁卡因青霉素、头孢唑啉钠及红霉素配伍后对金葡萄的体外抑菌效果明显增强;与头孢拉定、头孢唑啉钠及普鲁卡因青霉素配伍后对克氏肺炎杆菌的体外抑菌效果有不同程度的增强。结论:对于不同的细菌感染 相似文献
95.
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97.
Linkage of the MHC to familial multiple sclerosis suggests genetic heterogeneity. The Multiple Sclerosis Genetics Group 总被引:5,自引:0,他引:5
Haines JL; Terwedow HA; Burgess K; Pericak-Vance MA; Rimmler JB; Martin ER; Oksenberg JR; Lincoln R; Zhang DY; Banatao DR; Gatto N; Goodkin DE; Hauser SL 《Human molecular genetics》1998,7(8):1229-1234
Multiple sclerosis (MS) is a demyelinating autoimmune disease of the
central nervous system. While its etiology is not well understood, genetic
factors are clearly involved. Until recently, most genetic studies in MS
have been association studies using the case-control design testing
specific candidate genes and studying only sporadic cases. The only
consistently replicated finding has been an association with the HLA-DR2
allele within the major histocompatibility complex (MHC) on chromosome 6.
Using the genetic linkage design, however, evidence for and against linkage
of the MHC to MS has been found, fostering suggestions that sporadic and
familial MS have different etiologies. Most recently, two of four genomic
screens demonstrated linkage to the MHC, although specific allelic
associations were not tested. Here, a dataset of 98 multiplex families was
studied to test for an association to the HLA-DR2 allele in familial MS and
to determine if genetic linkage to the MHC was due solely to such an
association. Three highly polymorphic markers (HLA-DR, D6S273 and TNFbeta)
in the MHC demonstrated strong genetic linkage (parametric lod scores of
4.60, 2.20 and 1.24, respectively) and a specific association with the
HLA-DR2 allele was confirmed (TDT; P < 0.001). Stratifying the results
by HLA-DR2 status showed that the linkage results were limited to families
segregating HLA-DR2 alleles. These results demonstrate that genetic linkage
to the MHC can be explained by the HLA-DR2 allelic association. They also
indicate that sporadic and familial MS share a common genetic
susceptibility. In addition, preliminary calculations suggest that the MHC
explains between 17 and 62% of the genetic etiology of MS. This
heterogeneity is also supported by the minority of families showing no
linkage or association with loci within the MHC.
相似文献
98.
99.
L. C. Willcocks A. N. Chaudhry J. C. Smith S. Ojha R. Doffinger C. J. E. Watson K. G. C. Smith 《American journal of transplantation》2007,7(8):2006-2011
Different immunosuppressant regimens vary in their effects on antibody responses to vaccination. The combination of prednisolone and azathioprine has only a minor effect, whereas the addition of ciclosporin attenuates protective antibody responses to influenza vaccination. The effect of sirolimus, a new immunosuppressant, on vaccine responses has been little studied. Thirty-two hepatic or renal transplant patients randomized to calcineurin inhibitor-based or sirolimus-based immunosuppression were vaccinated against influenza and pneumococcus. Following tri-valent influenza vaccination, a similar rise in antibody titer occurred in sirolimus and calcineurin inhibitor (CNI) treated patients, though sirolimus treated patients developed a 'protective' titer to more influenza antigens. The pneumococcal polysaccharide vaccine was equally effective in both groups. Hence, vaccination guidelines in place for CNI treated patients are likely to be appropriate for transplant recipients maintained on sirolimus. 相似文献
100.
PC Chamyal A Mehta SL Ojha JR Bhardwaj 《Indian journal of otolaryngology and head and neck surgery》1991,43(1):26-27
Primary tuberculous pathology in nasolpolypi is a rare condition. A case of bilateral ethmoidal polypi with tubercular lesion diagnosed on histopathologlcal examination is being reported and the available relevant literature has been reviewed. 相似文献