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931.
Nobuhiko Kobayashi Takanori Yasu Satoshi Yamada Nobuki Kudo Masatoshi Kuroki Kunio Miyatake Masanobu Kawakami Muneyasu Saito 《Circulation journal》2003,67(7):630-636
Microbubbles have been reported to enhance ultrasound (US)-related side effects in animal systems. The present study investigated the influence of contrast ultrasonography (US) with perflutren lipid microspheres, a recently developed second-generation contrast agent, on microvessels. Rat mesentery was exposed to 1.8-MHz pulsed US with intravenous injection of perflutren (0.1 or 1.0 ml/kg) or Levovist (300 mg/kg), and the microvessel bleeding and endothelial cell injury was examined. Impaired endothelial cells were identified by the fluorescence of propidium iodide. Microvessel bleeding was examined also in the rat myocardium. The interaction between 0.1 ml/kg of perflutren and US exposure did not cause microvessel bleeding, and did not increase endothelial cell injury compared with the sham operation, unless frequent, strong US exposure occurred. When the dose was increased to 1.0 ml/kg, the combination of perflutren and US exposure resulted in capillary bleeding and increased endothelial cell injury in capillaries and venules (p<0.01). However, the incidence of microvessel bleeding and endothelial cell injury did not exceed that with Levovist microbubbles. In the myocardium, microvessel bleeding was not observed under any conditions. In conclusion, perflutren lipid microspheres enhanced US-related microvessel injury as with other contrast agents at the dose of 1.0 ml/kg, but not with 0.1 ml/kg and the appropriate US setting. 相似文献
932.
S. Hashino M. Imamura S. Kobayashi H. Kobayashi M. Kasai T. Miyazaki 《Annals of hematology》1993,66(3):135-137
Summary We report a case study of a patient suffering from T-lymphoblastic lymphoma, for whom autologous T-cell-depleted bone marrow transplantation was carried out. Low-dose cyclosporin A (CsA) was administered just after autologous bone marrow transplantation (ABMT) for induction of autologous graft-versus-host disease. Three months later, the lymphoma relapsed with marked monoclonal gammopathy of the immunoglobulin A type, which had not been seen before ABMT. It is suggested that the regrowth of the lymphoma cells was related to the maturation of B cells or the secretion of immunoglobulins from plasma cells, associated with some cytokines produced under the condition of an abnormal immunological circumstance after ABMT plus CsA. 相似文献
933.
Gln27Glu and Arg16Gly polymorphisms of the beta2-adrenergic receptor gene are not associated with obesity in Japanese men 总被引:1,自引:0,他引:1
Hayakawa T Nagai Y Kahara T Yamashita H Takamura T Abe T Nomura G Kobayashi K 《Metabolism: clinical and experimental》2000,49(9):1215-1218
The beta2-adrenergic receptor (beta2AR), beta3AR, or uncoupling protein 1 (UCP1) may play a pathogenic role in obesity. In Swedish Caucasians, a polymorphism at codon 27 (Gln27Glu) of the beta2AR gene was shown to be associated with obesity, but no such association was shown for a polymorphism of codon 16 (Arg16Gly). Thus, we investigated whether these polymorphisms contribute to obesity in 210 Japanese men. The frequencies of the Gln27Glu and Arg16Gly polymorphisms were 0.05 and 0.48, respectively, and there was no association with obesity. A strong linkage disequilibrium between the Gln27Glu and Arg16Gly polymorphisms was shown, but there was no apparent additive effect on the clinical or metabolic characteristics. Our results suggest that the Gln27Glu and Arg16Gly polymorphisms of the beta2AR gene are not a major contributing factor to obesity in Japanese men. 相似文献
934.
935.
Natsuko Kobayashi Hiroko Iijima Toshifumi Tada Yoko Shibata Takashi Nishimura Takashi Kumada Mariko Hashimoto Akiko Higashiura Masahiro Yoshida Junko Nishimura Nobuhiro Aizawa Naoto Ikeda Tomoyuki Takashima Ryo Takata Hiroki Nishikawa Yoshinori Iwata Hirayuki Enomoto Seiichi Hirota Etsuro Hatano 《Ultrasound in medicine & biology》2021,47(4):941-946
The aim of the study described here was to clarify the diagnostic value of the fluttering sign, a new sign that characterizes hepatic hemangiomas in gray-scale ultrasonography (US). It refers to a phenomenon in which the speckled echogenicity inside the hemangioma changes continuously and seems to be moving. A total of 172 hemangiomas diagnosed with contrast-enhanced US were evaluated. The fluttering sign was found in 123 of 172 hemangiomas (71.5%). Its prevalence was significantly higher than that of the marginal strong echo (89/172, 51.7%, p < 0.001), posterior acoustic enhancement (103/172, 59.9%, p = 0.031) and chameleon sign (100/172, 58.1%, p = 0.013). In addition, the fluttering sign was observed significantly more frequently in mixed or hypo-echoic tumors than in hyper-echoic tumors (p < 0.001), relatively large tumors (p < 0.001) and tumors that were less than 5 cm from the body surface (p = 0.015). The fluttering sign in gray-scale US has great potential to be a new complementary sign for the diagnosis of hemangioma. 相似文献
936.
Shoichiro Mineo Mamoru Niikura Shin-Ichi Inoue Masahiko Kuroda Fumie Kobayashi 《Infection and immunity》2013,81(10):3865-3871
Pregnant women are highly susceptible to malaria infection because of their low immunity and are at increased risk of maternal illness or death, in addition to spontaneous abortion, stillbirth, premature delivery, and low birth weight. However, the detailed pathogenesis of maternal malaria remains unclear. In this study, we evaluated a mouse model that shows similar severe pathological features of pregnant women during Plasmodium falciparum infection and investigated the pathogenesis of maternal malaria. Pregnant mice immunized by infection with an attenuated parasite, Plasmodium berghei XAT, were more susceptible to virulent P. berghei NK65 challenge/infection than were nonpregnant mice and showed high levels of parasitemia and a poor pregnancy outcome associated with placental pathology, such as accumulation of parasitized red blood cells, in the late phase of pregnancy. Notably, the pregnant immune mice challenged/infected with P. berghei NK65 developed liver injury associated with microvesicular fatty infiltration in late pregnancy. The pathological features were similar to acute fatty liver of pregnancy. Higher levels of gamma interferon and nitric oxide (NO) were found in plasma from pregnant immune mice infected with P. berghei NK65 than in plasma from nonpregnant mice. These findings suggest that development of liver injury and placental pathology in pregnant immune mice challenged/infected with P. berghei NK65 is accompanied by enhanced production of proinflammatory cytokines. 相似文献
937.
Norio Akuta Fumitaka Suzuki Taito Fukushima Yusuke Kawamura Hitomi Sezaki Yoshiyuki Suzuki Tetsuya Hosaka Masahiro Kobayashi Tasuku Hara Mariko Kobayashi Satoshi Saitoh Yasuji Arase Kenji Ikeda Hiromitsu Kumada 《Journal of clinical microbiology》2013,51(9):2862-2868
It is often difficult to predict the response to telaprevir-pegylated interferon (PEG-IFN)-ribavirin triple therapy and the appearance of telaprevir-resistant variants. The present study determined the predictive factors of a sustained virological response (SVR) to 12- or 24-week triple therapy (T12PR12 or T12PR24, respectively) in 194 Japanese patients infected with hepatitis C virus genotype 1b (HCV-1b). The study also evaluated whether ultradeep sequencing technology can predict at baseline the emergence of resistant variants after the start of therapy. Analysis of the data of the entire group indicated that an SVR was achieved in 78% of the patients. Multivariate analysis identified IL28B rs8099917 (genotype TT), the substitution of amino acid (aa) 70 (Arg70), response to prior treatment (naive or relapse), PEG-IFN dose (≥1.3 μg/kg of body weight), and treatment regimen (T12PR24) as significant determinants of SVR. Among patients of the T12PR24 group, 92% with genotype TT achieved an SVR, irrespective of a substitution at aa 70. In patients with the non-TT genotype, an SVR was achieved in 76% of those with Arg70, while only 14% of patients with the non-TT genotype, Gln70(His70), and nonresponse to ribavirin combination therapy achieved an SVR. Ultradeep sequencing was conducted for 17 patients who did not achieve an SVR to determine the emergence of resistant variants during therapy. De novo resistant variants were detected in 16 of 17 patients (94%), regardless of the variant frequencies detected at baseline. In conclusion, the results indicate that the response to triple therapy can be predicted by the combination of host, viral, and treatment factors and that it is difficult to predict at baseline the telaprevir-resistant variants that emerge during triple therapy, even with the use of ultradeep sequencing. 相似文献
938.
Norimasa Matsushita Atsushi Aruga Yasunobu Kobayashi Keishi Tanigawa Masakazu Yamamoto 《Immunopharmacology and immunotoxicology》2013,35(1):31-47
We aimed to induce three different immune cell subsets from a single blood sample from cancer patients to target different biological characters of cancer cells. In the presence of 6000 IU/ml IL-2, natural killer (NK) cells adhere to plastic. By using this ability, we could separate dendritic cells, T cells, and NK cells from peripheral blood mononuclear cells. The cultured NK cells demonstrated higher nonspecific cytotoxicity against tumor cell lines than did the T cells. Furthermore, adherent NK cells demonstrated higher cytotoxicity than nonadherent NK cells, although there was no difference between adherent and nonadherent NK cells in natural cytotoxicity receptors (NKp30, NKp44, NKp46) and NKG2D expression. With these results, we confirmed that we could induce dendritic cell, T cell, and higher cytotoxic NK cells from a single blood draw, and this methodology facilitates to the use of these cells for clinical grade conditions. 相似文献
939.
Mime Kobayashi Ryosuke Honda Tsuyoshi Ando Masao Tanihara 《Journal of biomaterials science. Polymer edition》2013,24(13):1161-1171
AbstractWe have developed biocompatible scaffolds that enable cell fate control with visible light. The scaffolds are based on synthetic collagen-like polypeptide, poly(prolyl-hydroxyprolyl-glycyl) {poly(Pro-Hyp-Gly)} which has been used for cosmetics and other healthcare applications. Bioactive peptides were conjugated to the scaffolds via photoactivation reaction utilizing 488?nm visible light. In addition, the use of a photocleavable crosslinker enables dissociation of chemical moieties by 405?nm laser irradiation. The synthesis scheme enables optical control to attach and detach functional peptides in pre-patterned shapes. Using bone forming peptide (BFP), we demonstrate that calcium deposition by rat bone stromal cells can be directed on the scaffold. Using other signaling molecules and three-dimensional scaffolds, controlled differentiation of stem cells can be achieved by spatio-temporally specific irradiation of confocal microscope laser. 相似文献
940.
Giovanni Pellegrino Tanguy Hedrich Viviane Sziklas JeanMarc Lina Christophe Grova Eliane Kobayashi 《Human brain mapping》2021,42(11):3352
Interactions between interictal epileptiform discharges (IEDs) and distant cortical regions subserve potential effects on cognition of patients with focal epilepsy. We hypothesize that “healthy” brain areas at a distance from the epileptic focus may respond to the interference of IEDs by generating inhibitory alpha and beta oscillations. We predict that more prominent alpha‐beta oscillations can be found in patients with less impaired neurocognitive profile. We performed a source imaging magnetoencephalography study, including 41 focal epilepsy patients: 21 with frontal lobe epilepsy (FLE) and 20 with mesial temporal lobe epilepsy. We investigated the effect of anterior (i.e., frontal and temporal) IEDs on the oscillatory pattern over posterior head regions. We compared cortical oscillations (5–80 Hz) temporally linked to 3,749 IEDs (1,945 frontal and 1,803 temporal) versus an equal number of IED‐free segments. We correlated results from IED triggered oscillations to global neurocognitive performance. Only frontal IEDs triggered alpha‐beta oscillations over posterior head regions. IEDs with higher amplitude triggered alpha‐beta oscillations of higher magnitude. The intensity of posterior head region alpha‐beta oscillations significantly correlated with a better neuropsychological profile. Our study demonstrated that cerebral cortex protects itself from IEDs with generation of inhibitory alpha‐beta oscillations at distant cortical regions. The association of more prominent oscillations with a better cognitive status suggests that this mechanism might play a role in determining the cognitive resilience in patients with FLE. 相似文献