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31.
H. Mine H. Kawai K. Yokoi M. Akaike S. Saito 《Journal of molecular medicine (Berlin, Germany)》1996,74(8):471-477
To investigate the relationship between human T-lymphotropic virus (HTLV) types I and II and the pathogenesis of autoimmune thyroid diseases, we examined serum anti-thyroid antibodies in 1019 blood donors with or without serum anti-HTLV-I antibody as well as proviral DNA for HTLV-II in leukocyte DNA by the polymerase chain reaction in 395 blood donors with or without anti-thyroid antibodies. The frequency of donors with anti-HTLV-I antibody who also showed anti-thyroid antibodies (7.9%) tended to be higher than that (6.3%) among donors who did not have the anti-HTLV-I antibody. The frequency of anti-thyroid antibodies in 125 young male donors aged 16–39 years with anti-HTLV-I antibody (4.8%) was significantly higher (P<0.05) than that (0.6%) in 164 control donors without the antibody. In blood donors with anti-thyroid antibody, 25.0% of those with anti-HTLV-I antibody and 14.3% of those without the antibody had HTLV-II proviral DNA. In contrast, in donors without anti-thyroid antibody HTLV-II proviral DNA was detected in 2.3% of those with anti-HTLV-I antibody and in 0.6% of those without the anti body. Thus the detection rates in donors with anti-thyroid antibody were significantly higher (P<0.001) than those in donors without the antibody, regardless of HTLV-I infection. These results suggest that HTLV-I infection and the presence of HTLV-II proviral DNA may be independently related to the pathogenesis of autoimmune thyroid diseases.Abbreviations
HTLV
Human T-lymphotropic virus
-
PCR
Polymerase chain reaction 相似文献
32.
33.
Mitsui A Hamuro J Nakamura H Kondo N Hirabayashi Y Ishizaki-Koizumi S Hirakawa T Inoue T Yodoi J 《Antioxidants & redox signaling》2002,4(4):693-696
Transgenic (Tg) mice overexpressing human thioredoxin (TRX), a small redox-active protein, were produced to investigate the role of the protein in a variety of stresses. Bone marrow cells from TRX-Tg mice were more resistant to ultraviolet C-induced cytocide compared with those from wild type (WT) C57BL/6 mice. TRX-Tg mice exhibited extended median and maximum life spans compared with WT mice. Telomerase activity in spleen tissues in TRX-Tg mice was higher than that in WT mice. These results suggest that overexpression of TRX results in resistance against oxidative stress and a possible extension of life span without apparent abnormality in mammals. 相似文献
34.
Satoshi Kitajima Sachiko Miyagawa-Tomita Tohru Inoue Jun Kanno Yumiko Saga 《Developmental dynamics》2006,235(2):395-402
Previous fate mapping analysis, using Cre recombinase driven by the Mesp1 locus, revealed that Mesp1 is expressed in almost all of the precursors of the cardiovascular system, including the endothelium, endocardium, myocardium, and epicardium. Mesp1-nonexpressing cells were found to be restricted to the outflow tract cushion and along the interventricular septum (IVS), which is a location that is suggestive of specialized cardiac conduction system (CCS). In our current study, we examined the identity of these IVS cells by using the pattern of beta-galactosidase activity in CCS-lacZ mice. In addition, by crossing Mesp1-Cre and floxed GFP reporter mice with CCS-lacZ mice, we have calculated that approximately 20% of the ventricular CCS within the IVS corresponds to Mesp1-nonexpressing cells. These data suggest that the ventricular CCS is of heterocellular origin. Furthermore, we indicate a possibility that a population of the cells that contribute to the ventricular CCS might be distinguished at an early stage of development. 相似文献
35.
Chong-Su Cho Tadashi K
moto Akira Nakagami Tohru Kawai 《Macromolecular chemistry and physics.》1979,180(8):1951-1959
Ionic polymer-polymer interaction was studied in aqueous solution for poly(L -lysine) (PLL) and sulfated poly(vinyl alcohol) (PVS) as functions of pH, the degree of sulfation, the functional unit mole ratio of the two polymers and temperature by means of circular dichroism and viscosity measurements. In all the cases studied, strong inter-polymer complexes were formed at the functional unit mole ratio (VS)/(LL) higher than 1. Although PLL itself is well known to take the α-helical conformation at such a high pH as 11, the PLL conformation in the PLL/PVS complexes did not depend on pH but on the degree of sulfation: at room temperature, PLL took random coil conformation in PLL/PVS-25 (25: degree of sulfation in mole-%) and PLL/PVS-30, and the α-helical conformation (helicity of 70%) in PLL/PVS-46 and PLL/PVS-95. Models for the complex structures are postulated. Methanesulfonic acid did not influence the conformational transition of PLL, supporting that a polymer effect took place in the complex formation between PLL and PVS. Thermal effect on the PLL conformation in the complex is also discussed. 相似文献
36.
37.
Yasuyuki Tezuka Kiyokazu Imai Mitsuyoshi Oshima Tohru Chiba 《Macromolecular chemistry and physics.》1990,191(3):681-690
A structural study on O-methyl-O-hydroxypropylcellulose (MHPC) and on O-methyl-O-hydroxyethylcellulose (MHEC) was performed by means of a 13C NMR analysis after acetylation of the unsubstituted hydroxyl groups at the anhydroglucose ring and those at the end of the substituents. The carbonyl signal of the acetyl group in acetylated MHPC and MHPC samples was found to be resolved into four peaks according to the location of the acetyl function either at the 2-, 3- and 6-position of an anhydroglucose unit or at the end of an oligo(oxyalkylene) substituent, allowing to determine the distribution of methyl and oligo(oxyalkylene) substituent groups. The methyl signal of the methoxy group in MHPC was also found to be sensitive to its position either at the anhydroglucose unit or at the end of the oligo(oxypropylene) substituent. 相似文献
38.
Liang Shan Yasushi Nakamura Misa Nakamura Toyoharu Yokoi Kennichi Kakudo 《Pathology international》1998,48(8):569-574
Hyperparathyroidism refers to a term representing a wide spectrum of parathyroid disorders that are characterized by the increased production of parathyroid hormone. Hyperparathyroidism was once thought to be tare but is now more commonly recognized, aifecting 1 in 500 women over 40 years of age. Yet the interpretation of parathyroid pathology is still controversial and confusing. Over the past 10 years, genetic changes ( ret and menin genes) involved in the pathogenesis of MEN 2 and MEN 1 have been discovered in succession. Different mutations of the calcium-sensing receptor gene have been identified in neonatal severe hyperparathyroidism and familial hypocalciuric hypercal-cemia, respectively. The HRPT 2 gene responsible for the development of heredltaty hyperparathyroidism and jaw tumors has been localized on the 1q21–31 locus. Several genetic alterations have also been characterized in primary and secondary hyperparathyroidism. Different genetic alterations appear to involve the development of different types of hyperparathyroidism. These novel advances give us new insights into the pathogenesis of hyperparathyroidism and allow better differentiation between the different types of parathyroid disorders. 相似文献
39.
Charcot-Marie-Tooth disease (CMT) is a heterogeneous disorder and is traditionally classified into two major types, CMT type 1 (CMT1) and CMT type 2 (CMT2). Most CMT1 patients are associated with the duplication of 17p11.2-p12 (CMT1A duplication) and small numbers of patients have mutations of the peripheral myelin protein 22 (PMP22), myelin protein zero (MPZ), connexin 32 (Cx32/GJB1), and early growth response 2 (EGR2) genes. Some mutations of MPZ and Cx32 were also associated with the clinical CMT2 phenotype. We constructed denaturing gradient gel electrophoresis (DGGE) analysis as a screening method for PMP22, MPZ, and Cx32 mutations and studied 161 CMT patients without CMT1A duplication. We detected 27 mutations of three genes including 15 novel mutations; six of PMP22, three of MPZ, and six of Cx32. We finally identified 21 causative mutations in 22 unrelated patients and five polymorphic mutations. Eighteen of 22 patients carrying PMP22, MPZ, or Cx32 mutations presented with CMT1 and four of them with MPZ or Cx32 mutations presented with the CMT2 phenotype. DGGE analysis was sensitive for screening for those gene mutations, but causative gene mutation was not identified in many of the Japanese patients with CMT, especially with CMT1. Other candidate genes should be studied to elucidate the genetic basis of Japanese CMT patients. 相似文献
40.