全文获取类型
收费全文 | 1204篇 |
免费 | 67篇 |
国内免费 | 1篇 |
出版年
2022年 | 9篇 |
2021年 | 9篇 |
2020年 | 8篇 |
2019年 | 10篇 |
2018年 | 14篇 |
2017年 | 16篇 |
2016年 | 20篇 |
2015年 | 29篇 |
2014年 | 35篇 |
2013年 | 73篇 |
2012年 | 72篇 |
2011年 | 65篇 |
2010年 | 38篇 |
2009年 | 36篇 |
2008年 | 61篇 |
2007年 | 51篇 |
2006年 | 71篇 |
2005年 | 53篇 |
2004年 | 47篇 |
2003年 | 36篇 |
2002年 | 52篇 |
2001年 | 34篇 |
2000年 | 39篇 |
1999年 | 30篇 |
1998年 | 10篇 |
1997年 | 12篇 |
1995年 | 8篇 |
1993年 | 9篇 |
1992年 | 23篇 |
1991年 | 25篇 |
1990年 | 14篇 |
1989年 | 16篇 |
1988年 | 16篇 |
1987年 | 12篇 |
1986年 | 12篇 |
1985年 | 15篇 |
1984年 | 9篇 |
1983年 | 11篇 |
1981年 | 11篇 |
1980年 | 10篇 |
1979年 | 12篇 |
1978年 | 8篇 |
1975年 | 10篇 |
1974年 | 8篇 |
1973年 | 11篇 |
1972年 | 9篇 |
1971年 | 11篇 |
1969年 | 12篇 |
1968年 | 13篇 |
1966年 | 11篇 |
排序方式: 共有1272条查询结果,搜索用时 31 毫秒
991.
Amano T Ichinose M Koga S Inoue Y Nishiyasu T Kondo N 《Journal of applied physiology (Bethesda, Md. : 1985)》2011,111(2):524-529
To investigate the effects of different training methods on nonthermal sweating during activation of the muscle metaboreflex, we compared sweating responses during postexercise muscle occlusion in endurance runners, sprinters, and untrained men under mild hyperthermia (ambient temperature, 35°C; relative humidity, 50%). Ten endurance runners, nine sprinters, and ten untrained men (maximal oxygen uptakes: 57.5 ± 1.5, 49.3 ± 1.5, and 36.6 ± 1.6 ml·kg(-1)·min(-1), respectively; P < 0.05) performed an isometric handgrip exercise at 40% maximal voluntary contraction for 2 min, and then a pressure of 280 mmHg was applied to the forearm to occlude blood circulation for 2 min. The Δ change in mean arterial blood pressure between the resting level and the occlusion was significantly higher in sprinters than in untrained men (32.2 ± 4.4 vs. 17.3 ± 2.6 mmHg, respectively; P < 0.05); however, no difference was observed between distance runners and untrained men. The Δ mean sweating rate (averaged value of the forehead, chest, forearm, and thigh) during the occlusion was significantly higher in distance runners than in sprinters and untrained men (0.38 ± 0.07, 0.19 ± 0.03, and 0.11 ± 0.04 mg·cm(-2)·min(-1), respectively; P < 0.05) and did not differ between sprinters and untrained men. Our results suggest that the specificity of training modalities influences the sweating response during activation of the muscle metaboreflex. In addition, these results imply that a greater activation of the muscle metaboreflex does not cause a greater sweating response in sprinters. 相似文献
992.
Ken Kono Eri Takeda Hiromi Tsutsui Ayumu Kuroishi Amy E. Hulme Thomas J. Hope Emi E. Nakayama Tatsuo Shioda 《PloS one》2013,8(8)
Human immunodeficiency virus type 1 (HIV-1) productively infects only humans and chimpanzees, but not Old World monkeys, such as rhesus and cynomolgus (CM) monkeys. To establish a monkey model of HIV-1/AIDS, several HIV-1 derivatives have been constructed. We previously generated a simian-tropic HIV-1 that replicates efficiently in CM cells. This virus encodes a capsid protein (CA) with SIVmac239-derived loops between α-helices 4 and 5 (L4/5) and between α-helices 6 and 7 (L6/7), along with the entire vif from SIVmac239 (NL-4/5S6/7SvifS). These SIVmac239-derived sequences were expected to protect the virus from HIV-1 restriction factors in monkey cells. However, the replicative capability of NL-4/5S6/7SvifS in human cells was severely impaired. By long-term cultivation of human CEM-SS cells infected with NL-4/5S6/7SvifS, we succeeded in partially rescuing the impaired replicative capability of the virus in human cells. This adapted virus encoded a G-to-E substitution at the 116th position of the CA (NL-4/5SG116E6/7SvifS). In the work described here, we explored the mechanism by which the replicative capability of NL-4/5S6/7SvifS was impaired in human cells. Quantitative analysis (by real-time PCR) of viral DNA synthesis from infected cells revealed that NL-4/5S6/7SvifS had a major defect in nuclear entry. Mutations in CA are known to affect viral core stability and result in deleterious effects in HIV-1 infection; therefore, we measured the kinetics of uncoating of these viruses. The uncoating of NL-4/5S6/7SvifS was significantly slower than that of wild type HIV-1 (WT), whereas the uncoating of NL-4/5SG116E6/7SvifS was similar to that of WT. Our results suggested that the lower replicative capability of NL-4/5S6/7SvifS in human cells was, at least in part, due to the slower uncoating of this virus. 相似文献
993.
Kayoko?Ichikawa Yoshimitsu?Takahashi Masahiko?Ando Tokie?Anme Tatsuro?Ishizaki Hinako?Yamaguchi Takeo?NakayamaEmail author 《BioPsychoSocial medicine》2013,7(1):14
Background
Although social skills training programs for people with high-functioning autism (HFA) are widely practiced, the standardization of curricula, the examination of clinical effectiveness, and the evaluation of the feasibility of future trials have yet to be done in Asian countries. To compensate for this problem, a Japanese pilot randomized controlled trial (RCT) of the Treatment and Education of Autistic and Related Communication Handicapped Children (TEACCH)-based group social skills training for children with HFA and their mothers was conducted.Methods
Eleven children with HFA, aged 5–6 years, and their mothers were randomly assigned to the TEACCH program (n=5) or a waiting-list control group (n=6). The program involved comprehensive group intervention and featured weekly 2-hour sessions, totaling 20 sessions over six months. The adaptive behaviors and social reciprocity of the children, parenting stress, and parent–child interactions were assessed using the Strengths and Difficulties Questionnaire (SDQ), Parenting Stress Index (PSI), Beck depression inventory-II (BDI-II), and Interaction Rating Scale (IRS).Results
Through this pilot trial, the intervention and evaluation of the program has been shaped. There were no dropouts from the program and the mothers’ satisfaction was high. The outcome measurements improved more in the program group than in the control group, with moderate effect sizes (SDQ, 0.71; PSI, 0.58; BDI-II, 0.40; and IRS, 0.69). This pilot trial also implied that this program is more beneficial for high IQ children and mothers with low stress than for those who are not.Conclusion
We have standardized the TEACCH program, confirmed the feasibility of a future trial, and successfully estimated the positive effect size. These findings will contribute to a larger trial in the future and to forthcoming systematic reviews with meta-analyses.Trial registration
UMIN000004560994.
Yuichi Kano Tatsuro Sato Liangliang Huang Chris Wood Kazuhiro Bessho Tomotaka Matsumoto Yukihiro Shimatani Jun Nakajima 《Landscape and Ecological Engineering》2013,9(2):289-298
We provide the first evidence for navigation impact on resident river fish in China. The survey was conducted in the East Tiaoxi River that discharges into Lake Taihu near Shanghai, on which cargo ship traffic has dramatically increased in the recent economic development period. Water turbidity, ship traffic and other environmental factors were evaluated at 29 sites on the river. In a multiple regression model with the stepwise method, turbidity was significantly correlated with ship traffic (R 2 = 0.53). Another survey was conducted at 46 sites in the same area of the river, in which environmental factors were evaluated and fish individuals were electrofished. A generalised linear model with the stepwise method was applied to predict ecological indicators of the fish assemblage (species richness, individual density and Shannon’s diversity index) based on environmental factors. The results showed that the indicators were negatively correlated with turbidity and presence of artificial shore embankment structures. Another analysis further showed that the negative effect of turbid water was especially considerable for fish of smaller size. In conclusion, cargo ship traffic has a negative impact on fish assemblage, especially on smaller individuals, in the East Tiaoxi River. A higher profile for conservation actions and consideration of environmental impacts of such traffic should be given increasing focus for this and other similar East Asian water courses. 相似文献
995.
Yasushi Mandai Daisuke Takahashi Koji Hase Yuuki Obata Yukihiro Furusawa Masashi Ebisawa Tomoo Nakagawa Toru Sato Tatsuro Katsuno Yasushi Saito Takeshi Shimaoka Osamu Yokosuka Kotaro Yokote Hiroshi Ohno 《PloS one》2013,8(6)
CD4+ T cells play a central role in the development of inflammatory bowel disease (IBD) via high-level production of effector cytokines such as IFN-γ and TNF-α. To better characterize the colitogenic CD4+ T cells, we examined their expression of CXCR6, a chemokine receptor that is expressed by T cells upon activation and is upregulated in several inflammatory diseases. We found that 80% of colonic lamina propria CD4+ T cells expressed CXCR6 in the CD45RBhigh T cell-transferred colitis model. CXCR6 expression was similarly upregulated in inflamed mucosa of patients with Crohn’s disease. Although surface marker analysis demonstrated that both CXCR6+ and CXCR6− CD4+ T-cell subsets consist of the cells with effector and effector-memory cells, the more cells in the CXCR6+ subset produced IFN-γ and TNF-α compared to CXCR6− subset, and only the CXCR6+ subset produced IL-17A. Nevertheless, adoptive retransfer of lamina propria CXCR6+ T cells into Rag1
−/− recipients failed to induce the disease due to limited expansion of the transferred cells. By contrast, retransfer of CXCR6− cells evoked colitis similar to that observed in CD4+CD45RBhigh T cell-transferred mice, and resulted in their conversion into CXCR6+ cells. Collectively, these observations suggest that the CXCR6+CD4+ T-cell subset consists of terminally differentiated effector cells that serve as the major source of effector cytokines in the inflamed tissue, whereas CXCR6−CD4+ T-cell subset serves as a colitogenic memory compartment that retains the ability to proliferate and differentiate into CXCR6+CD4+ T cells. 相似文献
996.
We measured the adhesion of candidate probiotic lactic acid bacteria (LAB) to carp intestinal mucus. The percentage of adherent bacteria varied among strains. Four strains, two with high adhesion and two with low adhesion in vitro, were tested for in vivo colonization ability. Carp were fed LAB-containing feed for 12 d, and then unsupplemented feed until day 33, and the numbers and compositions of intestinal LAB were analyzed during the entire period. LAB with lower in vitro adhesion disappeared quickly from the intestine after LAB feeding stopped. LAB with higher in vitro adhesion remained in the intestine 3 weeks after LAB feeding stopped, indicating a strong correlation between mucus adhesion in vitro and colonization ability in vivo. Next we isolated nine candidate probiotic LAB with high in vitro mucus-binding ability. Three of them were fed to carp, and all three were stably maintained in the intestine. 相似文献
997.
Shimizu K Suzuki N Imai T Aizawa K Nanba H Hanaoka Y Kuno S Mesaki N Kono I Akama T 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(9):2565-2572
The purpose of this study was to examine the effects of exercise training on age-related impairment of immune parameters related to T-cell activation in elderly individuals. Twenty-four elderly subjects were assigned to an exercise training group (EXC: 3 men, 9 women; age 61-76 years) or a nonexercise control group (CON: 4 men, 8 women; age 62-79 years). Subjects in EXC participated in exercise sessions 2 d·wk(-1) for 12 weeks. The training session included stretching and endurance exercise (10 minutes), resistance training comprised leg extension, leg press, hip abduction, and hip adduction using exercise machine and each subject's body weight. Subjects in CON maintained their normal physical activity levels during the study period. Blood samples were collected before and after the training period. Samples were measured for the numbers of leukocytes, lymphocytes, and monocytes, and for CD3(+), CD4(+), CD8(+), CD28(+)CD4(+), CD28(+)CD8(+), TRL-4(+)CD14(+), and CD80(+)CD14(+) cells. The number of leukocytes, lymphocytes, monocytes, CD3(+), CD4(+), and CD8(+) cells did not change after 12 weeks in either EXC or CON. The number of CD28(+)CD8(+) cells increased significantly after training in EXC (p ≤ 0.05), although CON showed no significant change. In the EXC group, CD80(+)CD14(+) cell counts were significantly higher after training (p ≤ 0.05), but the TLR-4(+)CD14(+) cell counts were unchanged. In the CON group, no significant alteration existed in TLR-4(+)CD14(+) and CD80(+)CD14(+) cell numbers. In conclusion, exercise training in elderly people is associated with increased CD28-expressing Tc cells and CD80-expressing monocytes. Therefore, exercise training might upregulate monocyte and T-cell-mediated immunity in elderly people. 相似文献
998.
Interleukin-6 (IL-6) plays a crucial role in malignant diseases, such as rheumatoid arthritis, Castleman disease, and multiple
myeloma, and as such, is an attractive therapeutic target. Here, the authors isolated a novel IL-6 inhibitor peptide by in
vitro selection using mRNA display. The authors first used a random-primed human cDNA library to isolate IL-6-binding peptides.
After four rounds of selection, a 19-amino acid peptide named CA11 was selected and confirmed to specifically interact with
IL-6. The authors then performed an alanine scan analysis of CA11 and determined the amino acid residues necessary to interact
with IL-6. Next, the authors constructed a CA11-based partially randomized library and after ten more rounds of selection,
isolated several groups of peptides. The most frequently occurring sequence, RA07, bound to IL-6 with 3 to 4-fold higher affinity
than CA11. Furthermore, RA07 inhibited IL-6-dependent KT-3 cell proliferation in a dose-dependent manner. ELISAs revealed
that RA07 could not inhibit IL-6 from binding to the IL-6 receptor (IL-6R), but could inhibit the IL-6/IL-6 complex binding
to gp130. 相似文献
999.
For production of a new type of functional liposome whose destabilization can be triggered by a combination of a temperature signal and acidic pH signal, we prepared liposomes modified with hyperbranched poly(glycidol) derivatives having N-isopropylamide and carboxyl groups. HeLa cells incubated with the dual signal-responsive liposomes encapsulating a water-soluble fluorescent dye pyranine at 28 °C displayed punctate fluorescence of pyranine, indicating that the liposomes were trapped in endosome. However, after heating at 45 °C for 15 min, the same cells exhibited diffuse fluorescence of pyranine, indicating that destabilization of the liposomes in endosome with an acidic environment in combination with the brief heating caused efficient transfer of the contents into cytosol. The dual signal-responsive liposomes might have usefulness for site-specific delivery of membrane-impermeable molecules, which exhibit bioactivities in the intracellular spaces, such as siRNA and proteins. 相似文献
1000.
Tokuda N Igarashi K Shimamura T Yurugi-Kobayashi T Shiroishi M Ito K Sugawara T Asada H Murata T Nomura N Iwata S Kobayashi T 《Protein expression and purification》2011,79(1):81-87
Anion exchangers are membrane proteins that have been identified in a wide variety of species, where they transport Cl(-) and HCO3(-)across the cell membrane. In this study, we cloned an anion-exchange protein from the genome of the basidiomycete Phanerochaete chrysosporium (PcAEP). PcAEP is a 618-amino acid protein that is homologous to the human anion exchanger (AE1) with 22.9% identity and 40.3% similarity. PcAEP was overexpressed by introducing the PcAEP gene into the genome of Pichia pastoris. As a result, PcAEP localized in the membrane of P. pastoris and was solubilized successfully by n-dodecyl-β-D-maltoside. His-tagged PcAEP was purified as a single band on SDS-PAGE using immobilized metal affinity chromatography and gel filtration chromatography. Purified PcAEP was found to bind to SITS, an inhibitor of the AE family, suggesting that the purified protein is folded properly. PcAEP expressed and purified using the present system could be useful for biological and structural studies of the anion exchange family of proteins. 相似文献