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101.
Influence of polymorphisms in the genes for cytokines and glutathione S-transferase omega on sporadic Alzheimer's disease 总被引:2,自引:0,他引:2
We studied promoter region polymorphisms in the interleukin (IL)-1alpha, IL-1beta, IL-6, IL-10, tumor necrosis factor, and transforming growth factor (TGF)-beta1 genes in Japanese patients with Alzheimer's disease (AD) (n = 172) and normal controls (n = 163). We also examined an association of a polymorphism located in the glutathione S-transferase omega 1 (GSTO-1) gene region with AD patients. None of these genotypes or allele frequencies showed a significant difference between AD patients and controls. We also failed to detect any difference in the disease onset between each genotype of the seven polymorphisms. Although AD patients carrying high producer alleles of TGF-beta1 and IL-1beta or TGF-beta1 and IL-6 showed a tendency for an early onset of the disease, neither of these combined effects reached a significant level after multiple comparisons. Our findings suggest that genetic polymorphisms in the cytokines and GSTO do not play a major role in Japanese AD patients. 相似文献
102.
Shigeki Sekine Tadakazu Shimoda Satoshi Nimura Yukihiro Nakanishi Takayuki Akasu Hitoshi Katai Takuji Gotoda Tatsuhiro Shibata Michiie Sakamoto Setsuo Hirohashi 《Modern pathology》2004,17(11):1421-1426
We report a patient with familial adenomatous polyposis who developed high-grade dysplasia against a background of fundic gland polyposis. Two large high-grade dysplasia lesions were found in the gastric body, where numerous fundic gland polyps were present. In both lesions, the dysplastic epithelium covered non-neoplastic oxyntic glands that occasionally exhibit cystic changes. A genetic analysis for APC (adenomatous polyposis coli) revealed a somatic 50-bp deletion involving codons 1502-1517 and 2-bp deletion at codon 1465 in each lesion of high-grade dysplasia. In contrast, six of the 18 fundic gland polyps were found to harbor an identical mutation: 1-bp insertion at codon 1556. Both lesions of high-grade dysplasia and the fundic gland polyps were similarly located in the fundic gland area and were caused by the inactivation of APC; however, their mutation profiles of APC were different. These results imply that fundic gland polyps and high-grade dysplasia of the stomach have distinct preferences for APC genotypes in their development. 相似文献
103.
Kida T Nishihira Y Hatta A Wasaka T Nakata H Sakamoto M Nakajima T 《European journal of applied physiology》2003,89(3-4):326-330
We investigated the relationship between somatosensory event-related potentials (ERP) and the variation of reaction time (RT).
For this purpose, we recorded the ERPs (N250 and P300) in fast- and slow-reaction trials during a somatosensory discrimination
task. Strong, standard, and weak target electrical stimuli were randomly delivered to the left median nerve at the wrist with
a random interstimulus interval (900–1,100 ms). All the subjects were instructed to respond by pressing a button with their
right thumb as fast as possible whenever a target stimulus was presented. We divided all the trials into fast- and slow-RT
trials and averaged the data. N250 latency tended to be delayed when the RT was slow, but not significantly. P300 latency
was delayed significantly when the RT was slow, but to a much lesser extent than the RT delay, so we concluded that the change
of RT was not fully determined by the processes reflected by the somatosensory N250 or P300. Furthermore, the larger and earlier
P300 in the fast-RT trials implied that when larger amounts of attentional resources were allocated to a given task, the speed
of stimulus evaluation somewhat increased and RT was shortened to a great extent. N250 amplitude did not significantly vary
in the two RT clusters. In conclusion, the somatosensory N250 reflects active target detection, which is relatively independent
of the modulation of the response speed, whereas the somatosensory P300 could change without manipulation of either the stimulus
or the response processing demand.
Electronic Publication 相似文献
104.
The critical role of ocular-infiltrating macrophages in the development of choroidal neovascularization 总被引:9,自引:0,他引:9
Tsutsumi C Sonoda KH Egashira K Qiao H Hisatomi T Nakao S Ishibashi M Charo IF Sakamoto T Murata T Ishibashi T 《Journal of leukocyte biology》2003,74(1):25-32
Choroidal neovascularization (CNV) is directly related to visual loss in some eye diseases, such as age-related macular degeneration. Although several human histological studies have suggested the participation of macrophages in CNV formation, the precise mechanisms are still not fully understood. In this study, we elucidated the role of ocular-infiltrating macrophages in experimental CNV using CCR2 knockout (KO) mice, wild-type mice, and C57BL/6 (B6) mice. CCR2 is the receptor of monocyte chemoattractant protein-1, and the number of infiltrating macrophage and the area of CNV were significantly reduced in CCR2 KO mice. Enriched ocular-infiltrating macrophages from B6 mice actually showed angiogenic ability in a dorsal air sac assay. Moreover, their expression of class II, CD40, B7-1 and B7-2 molecules, and the mRNA for potential angiogenic factors, such as vascular endothelial growth factor, basic fibroblast growth factor, and tumor necrosis factor alpha, was also observed. Collectively, we conclude that ocular-infiltrating macrophages play an important role in CNV generation. 相似文献
105.
Akagi T Higashi A Tsugami H Sakamoto H Masuda Y Hishikawa Y 《Physics in medicine and biology》2003,48(22):N301-N312
At the Hyogo Ion Beam Medical Center (HIBMC) we have developed a new design method for the bar ridge filter used in proton therapy, taking into consideration the scattering and nuclear interaction effects within the filter itself, which are introduced in the design. In our beam delivery system, the bar ridge filter is employed as the range modulator. It is combined with the wobbler system, and produces a three-dimensionally uniform spread-out Bragg peak (SOBP). The design program predicts the three-dimensional dose distribution. Ridge filters of 3-12 cm SOBP in 1 cm increments were designed in the maximum radiation field for 150 MeV and 190 MeV proton beams so that a uniform physical dose area is obtained in the SOBP region three-dimensionally. Measurements were performed with the constructed ridge filters to verify the uniformity and these were compared with the predictions of the design program. The predictions and measurements were found to be in agreement except for the 12 cm SOBP. The uniformities were better than +/- 3.0% for all SOBPs produced. The ridge filters are now clinically in use. 相似文献
106.
K. Kurashima M. Fujimura M. Saito S. Sakamoto Y. Miyake K. Nishi T. Matsuda 《Allergy》1990,45(4):249-253
Slow-reacting substance of anaphylaxis (SRS-A) is an important factor mediating bronchoconstriction in asthma. We developed a guinea pig model for SRS-A mediated bronchoconstriction induced by antigen inhalation. Using this model, we investigated the effect of inhaled WP871, a new anti-allergic drug, on bronchoconstriction. Aerosol WP871 (0.01 and 0.033%) to some extent inhibited the antigen-induced bronchoconstriction in a dose-dependent fashion, but high-dose WP871 (0.1%) inhalation itself produced a non-specific bronchoconstriction. However, aerosol WP871 (0.033%) showed no inhibitory effect on bronchoconstriction caused by direct inhalation of leukotriene C4, a component of SRS-A. These findings indicate that aerosol WP871 does not antagonize SRS-A, but inhibits synthesis and/or release of SRS-A and has some non-specific bronchoconstrictive effect in high concentration. 相似文献
107.
Yoshiteru Sakamoto Dr Takehiko Watanabe Hideyuki Hayashi Yoshitaka Taguchi Hiroshi Wada 《Inflammation research》1985,17(1):32-37
The effect of about one hundred compounds on the activity of histidine decarboxylase partially purified from whole bodies of fetal rats was determined. Most of them at their 10 mM concentration had little effect on the enzyme activity; but 12 compounds inhibited the enzyme to a greater extent than 30%. Among these, except for -methylhistidine that has been known to be a strong and specific inhibitor, DOPA, homocysteine, cysteine, methionine and urocanic acid were the best inhibitors; -phenyllactic acid, phenylpyruvic acid and carnosine were less strong inhibitors; valine, oxaloacetic acid andN
-methylimidazole acetic acid were weak inhibitors. Histamine had no inhibitory action. Thus, the substrate binding site of histidine decarboxylase is very rigid and specific forl-histidine. 相似文献
108.
CD81 nucleotide mutation in hepatocellular carcinoma and lack of CD81 polymorphism in patients at stages of hepatitis C virus infection 总被引:1,自引:0,他引:1
Itakura J Nagayama K Enomoto N Sakamoto N Tazawa J Izumi N Marumo F Sato C 《Journal of medical virology》2001,63(1):22-28
Mechanisms determining the chronicity or the pattern of clinical course of hepatitis C virus (HCV) infections have not been clarified. Recently, CD81 was reported to bind the E2 protein of HCV and was suggested to function as a cellular receptor for HCV. Accordingly, the hypothesis was examined that CD81 polymorphism, if it exists, might correlate with certain clinical courses of HCV infection. CD81 cDNA sequences were determined from peripheral blood mononuclear cells (PBMCs). Twenty-four Japanese subjects were enrolled initially as follows: patients with chronic hepatitis C without cirrhosis (n = 3), patients with cirrhosis (n = 3), patients with cirrhosis complicated by hepatocellular carcinoma (HCC) (n = 3), patients with persistent HCV viremia without ALT elevation (n = 3), those with positive anti-HCV antibodies without evidence of HCV viremia (n = 3), and healthy volunteers (n = 9). In all PBMCs samples analyzed, no polymorphism was found in the CD81 cDNA sequence. The sequence was different, however, from the one reported previously at three nucleotide positions: a transversion to thymine instead of cytosine at nt 1130, a deletion at nt 1206, and a guanine insertion at nt 71. Subsequently, CD81 cDNA sequences from PBMCs and HCC tissue were compared among the other 6 patients with chronic hepatitis C bearing HCC. A comparative study of the CD81 sequences from HCC and PBMCs revealed that various nucleotide mutations existed only in the HCC samples in 3 out of 6 patients. Several mutations in the 3' non-coding region of CD81 cDNA were observed exclusively in HCC tissue suggesting its possible role in hepatocarcinogenesis. Because of the absence of polymorphisms, however, CD81 is unlikely to affect the progression of chronic hepatitis C in terms of chronicity, hepatitis activity, or disease stage. 相似文献
109.
110.
Tatsuo Sakamoto Hideo Tsukagoshi Peter J. Barnes K. Fan Chung 《Inflammation research》1993,39(3-4):111-117
We have investigated the effects of SR-48968, an NK2 receptor antagonist, and indomethacin, a cyclooxygenase inhibitor, against bronchoconstriction and airway microvascular leakage induced by bradykinin (BK) in anesthetized guinea pigs. In addition, we have determined whether these effects were mediated via bradykinin B2 receptor activation, using a B2 receptor antagonist HOE 140. Lung resistance (R
L) and extravasation of Evans blue dye into airway tissues were used as indexes of airway caliber and microvascular leakage, respectively. BK (15 nmol/kg i.v.) induced a significant increase inR
L and leakage of dye at all airway levels, responses which were completely abolished by HOE 140 (0.13 mg/kg i.v.). SR-48968 (1.5 mg/kg i.v.) had no effect against BK-induced airway effects. Indomethacin (5 mg/kg i.v.) completely blocked the increase inR
L and significantly inhibited the leakage of dye in peripheral intrapulmonary airway. In conclusion, bronchoconstriction induced by i.v. BK is mediated by release of cyclooxygenase products but not by stimulation of NK2 receptors, while the airway microvascular leakage only partly involves cyclooxygenase activation. Cyclooxygenase activation may occur following bradykinin B2 receptor stimulation. 相似文献