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991.
An HIV-1-infected T cell clone defective in IL-2 production and Ca2+ mobilization after CD3 stimulation 总被引:10,自引:0,他引:10
V L Perez T Rowe J S Justement S T Butera C H June T M Folks 《Journal of immunology (Baltimore, Md. : 1950)》1991,147(9):3145-3148
A chronically HIV-1-infected T cell clone (J1.1) derived from Jurkat cells was developed that possesses defects in CD3 signaling. This clone was phenotypically determined to be CD4- and express a reduced surface density of CD3 as compared with a pool of uninfected Jurkat clones. Although J1.1 could be induced with TNF-alpha to produce HIV-1 particles, stimulation via the CD3 (T3-Ti) complex, using mAb cross-linking, had no effect on viral production. Further investigation revealed that J1.1 secreted approximately 20-fold less IL-2 than did uninfected Jurkat cells after anti-CD3 treatment. In addition, a separate defect in Ca2+ mobilization was noted in the HIV-1-infected J1.1 line when compared with uninfected Jurkat cells after anti-CD3 cross-linking. The cell line described offers a new model in which to study the mechanisms of several defects directly imposed by HIV-1 on CD3+ cells. 相似文献
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993.
Joong Sun Kim Yeonghoon Son Min Ji Bae Seung Sook Lee Sun Hoo Park Hae June Lee Soong In Lee Chang Geun Lee Sung Dae Kim Wol Soon Jo Sung Ho Kim In Sik Shin 《PloS one》2015,10(11)
Although safe doses of radiation have been determined, concerns about the harmful effects of low-dose radiation persist. In particular, to date, few studies have investigated the correlation between low-dose radiation and disease development. Asthma is a common chronic inflammatory airway disease that is recognized as a major public health problem. In this study, we evaluated the effects of low-dose-rate chronic irradiation on allergic asthma in a murine model. Mice were sensitized and airway-challenged with ovalbumin (OVA) and were exposed to continuous low-dose-rate irradiation (0.554 or 1.818 mGy/h) for 24 days after initial sensitization. The effects of chronic radiation on proinflammatory cytokines and the activity of matrix metalloproteinase-9 (MMP-9) were investigated. Exposure to low-dose-rate chronic irradiation significantly decreased the number of inflammatory cells, methylcholine responsiveness (PenH value), and the levels of OVA-specific immunoglobulin E, interleukin (IL)-4, and IL-5. Furthermore, airway inflammation and the mucus production in lung tissue were attenuated and elevated MMP-9 expression and activity induced by OVA challenge were significantly suppressed. These results indicate that low-dose-rate chronic irradiation suppresses allergic asthma induced by OVA challenge and does not exert any adverse effects on asthma development. Our findings can potentially provide toxicological guidance for the safe use of radiation and relieve the general anxiety about exposure to low-dose radiation. 相似文献
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995.
996.
Heung Yong Jin Na Young Lee Hyun A. Ko Kyung Ae Lee 《Somatosensory & motor research》2016,33(3-4):186-195
Although diabetic peripheral neuropathy (DPN) and chemotherapy-induced peripheral neuropathy (CIPN) are different disease entities, they share similar neuropathic symptoms that impede quality of life for these patients. Despite having very similar downstream effects, there have been no direct comparisons between DPN and CIPN with respect to symptom severity and therapeutic responses. We compared peripheral nerve damage due to hyperglycemia with that caused by paclitaxel (PAC) treatment as represented by biochemical parameters, diverse sensory tests, and immunohistochemistry of cutaneous and sciatic nerves. The therapeutic effects of alpha-lipoic acid and DA-9801 were also compared in the two models. Animals were divided into seven groups (n?=?7–10) as follows: normal, diabetes (DM), DM?+?alpha-lipoic acid 100?mg/kg (ALA), DM?+?DA-9801 (100?mg/kg), paclitaxel-treated rat (PAC), PAC?+?ALA (100?mg/kg), and PAC?+?DA-9801 (100?mg/kg). The sensory thresholds of animals to mechanical, heat, and pressure stimuli were altered by both hyperglycemia and PAC when compared with controls, and the responses to sensory tests were different between both groups. There were no significant differences in the biochemical markers of blood glutathione between DM and PAC groups (p?>?.05). Quantitative comparisons of peripheral nerves by intraepidermal nerve fiber density (IENFD) analysis indicated that the DM and PAC groups were similar (6.18?±?1.03 vs. 5.01?±?2.57). IENFD was significantly improved after ALA and DA-9801 treatment in diabetic animals (7.6?±?1.28, 7.7?±?1.28, respectively, p?.05) but did not reach significance in the PAC-treated groups (6.05?±?1.76, 5.66?±?1.26, respectively, p?>?.05). Sciatic nerves were less damaged in the PAC-treated groups compared with the DM groups with respect to axonal diameter and area (8.60?±?1.14?μm vs. 6.66?±?1.07?μm, and 59.04?±?15.16?μm2 vs. 35.71?±?11.2?μm2, respectively, p?.05). Based on these results, the neuropathic manifestation and therapeutic responses of DPN may be different from other peripheral neuropathies. Therefore, specific pathogenic consideration according to peripheral neuropathy classification in addition to common treatments needs to be developed for management strategies of peripheral neuropathies. 相似文献
997.
Jeong‐Kyu KIM Chang‐Soo KANG Jong‐Kwon LEE Young‐Ran KIM Hye‐Yun HAN Hwa Kyung YUN 《Entomological Research》2005,35(2):117-120
Repellent efficacies of two natural aroma compounds, citronella and citronellal, against mosquitoes, Culex pipiens pallens, were evaluated both in field and in vitro. In vitro, the experiment was conducted with three controlled bands impregnated with 30% citronella extract, 15% citronella extract and 30% citronellal extract, and with bands impregnated 30% citronella in field. Data was obtained by the means of counting numbers bitten by mosquitoes per unit time, namely human bait method. Percentage repellencies of above three controlled bands were calculated at 86%, 73%, and 78%, respectively in vitro, and 80% in field, showing high repellent effectiveness against mosquitoes. This estimation was also confirmed by t‐test compared between control group and each experimental group. 相似文献
998.
IL-5 induces a Pgp-1 (CD44) bright B cell subpopulation that is highly enriched in proliferative and Ig secretory activity and binds to hyaluronate 总被引:14,自引:0,他引:14
S Murakami K Miyake C H June P W Kincade R J Hodes 《Journal of immunology (Baltimore, Md. : 1950)》1990,145(11):3618-3627
Pgp-1 expression was examined in unstimulated B cell populations and in B cells activated with several polyclonal stimuli. Flow cytometry analysis demonstrated that Pgp-1 expression increased when B cells were activated with supernatant of cloned Th2 cells, with LPS, or with IL-5, stimuli that induced polyclonal proliferation and differentiation. IL-5-primed B cells were phenotypically unique and could be divided into two distinct subpopulations based on the brightness of Pgp-1 expression. Furthermore, sterile sorting experiments showed that proliferating and differentiating B cells were highly enriched in a Pgp-1-bright, Ia-dull, B220-dull subpopulation. The possibility that Pgp-1 expressed on activated B cells functions as an adhesion molecule was evaluated by assessing adhesion of activated B cells to defined substrates. It was found that IL-5-activated B cells bound strongly to hyaluronate-coated surface, and this binding was specifically inhibited by anti-Pgp-1 Ab. These findings suggest that Pgp-1 expression is a useful marker which, under defined conditions, identifies the proliferating and differentiating subset of activated B cells. Moreover, the Pgp-1 bright subset of IL-5-primed B cells binds to hyaluronate in a Pgp-1-dependent manner that suggests a potential role of Pgp-1 in the in vivo adherence and trafficking of activated B cells. 相似文献
999.
Effects of Ethylene on the Kinetics of Curvature and Auxin Redistribution in Gravistimulated Roots of Zea mays 总被引:1,自引:1,他引:0 下载免费PDF全文
We tested the involvement of ethylene in maize (Zea mays L.) root gravitropism by measuring the kinetics of curvature and lateral auxin movement in roots treated with ethylene, inhibitors of ethylene synthesis, or inhibitors of ethylene action. In the presence of ethylene the latent period of gravitropic curvature appeared to be increased somewhat. However, ethylene-treated roots continued to curve after control roots had reached their final angle of curvature. Consequently, maximum curvature in the presence of ethylene was much greater in ethylene-treated roots than in controls. Inhibitors of ethylene biosynthesis or action had effects on the kinetics of curvature opposite to that of ethylene, i.e. the latent period appeared to be shortened somewhat while total curvature was reduced relative to that of controls. Label from applied 3H-indole-3-acetic acid was preferentially transported toward the lower side of stimulated roots. In parallel with effects on curvature, ethylene treatment delayed the development of gravity-induced asymmetric auxin movement across the root but extended its duration once initiated. The auxin transport inhibitor, 1-N-naphthylphthalamic acid reduced both gravitropic curvature and the effect of ethylene on curvature. Since neither ethylene nor inhibitors of ethylene biosynthesis or action prevented curvature, we conclude that ethylene does not mediate the primary differential growth response causing curvature. Because ethylene affects curvature and auxin transport in parallel, we suggest that ethylene modifies curvature by affecting gravity-induced lateral transport of auxin, perhaps by interfering with adaptation of the auxin transport system to the gravistimulus. 相似文献
1000.
Helen E. Gruber G. June Marshall Loyda M. Nolasco Mary E. Kirchen David L. Rimoin 《Biotechnic & histochemistry》1988,63(5):299-306
Human bone and cartilage specimens were evaluated for acid and alkaline phosphatase localization following varying fixation periods for fresh or frozen tissue. Formalin fixations of up to 183 hr were followed by embedment in methyl methacrylate; frozen tissue was examined either without fixation or following fixation for up to 1 hr and subsequent glycol or methyl methacrylate embedding. The humeral epiphysis of a young patient with osteogenic sarcoma showed optimum acid and alkaline phosphatase localization following fixation for periods up to 15 hr and embedding in methyl methacrylate. Frozen costochondral junction from a newborn with osteogenesis imperfecta type II showed optimum acid and alkaline phosphatase localization following 30 min fixation in formalin and embedding in methyl methacrylate or after 5 min fixation and embedding in glycol methacrylate. 相似文献