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991.
Sean D. Madsen Sean H. Jones H. Alan Tucker Margaret K. Giler Dyllan C. Muller Carson T. Discher Katie C. Russell Georgina L. Dobek Mimi C. Sammarco Bruce A. Bunnell Kim C. O'Connor 《Biotechnology and bioengineering》2020,117(1):ii-ii
In vivo mesenchymal stem cell (MSC) survival is relevant to therapeutic applications requiring engraftment and potentially to nonengraftment applications as well. MSCs are a mixture of progenitors at different stages of cellular aging, but the contribution of this heterogeneity to the survival of MSC implants is unknown. Here, we employ a biomarker of cellular aging, the decoy TRAIL receptor CD264, to compare the survival kinetics of two cell populations in human bone marrow MSC (hBM-MSC) cultures. Sorted CD264+ hBM-MSCs from two age-matched donors have elevated β-galactosidase activity, decreased differentiation potential and form in vitro colonies inefficiently relative to CD264− hBM-MSCs. Counterintuitive to their aging phenotype, CD264+ hBM-MSCs exhibited comparable survival to matched CD264− hBM-MSCs from the same culture during in vitro colony formation and in vivo when implanted ectopically in immunodeficient NIH III mice. In vitro and in vivo survival of these two cell populations were independent of colony-forming efficiency. These findings have ramifications for the preparation of hBM-MSC therapies given the prevalence of aging CD264+ cells in hBM-MSC cultures and the popularity of colony-forming efficiency as a quality control metric in preclinical and clinical studies with MSCs. 相似文献
992.
993.
Trang Thi Thu Tran Kiyoki Kitagawa Shinji Kitajima Tadashi Toyama Yasunori Iwata 《Biomarkers》2020,25(2):194-200
AbstractPurpose: We examined the relationship between autoantibodies to erythropoietin receptor (EPOR) and renal outcome in patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).Materials and methods: Sixty-three Japanese patients with AAV were enrolled and followed for a median of 31.4?months. Patients were screened for serum anti-EPOR antibodies using an enzyme-linked immunosorbent assay. Associations of anti-EPOR antibodies with clinical parameters were analyzed using logistic-regression models.Results: Anti-EPOR antibodies were detected in 7 (11%) of the 63 patients, and levels of the antibodies decreased with immunosuppressive therapy. The presence of anti-EPOR antibodies was associated with a higher Birmingham vasculitis activity score. In addition, anti-EPOR antibodies were more frequently observed in patients with renal outcomes, which was defined as a sustained 50% reduction in the estimated glomerular filtration rate from baseline, than in those without. Multiple logistic regression analysis revealed that presence of anti-EPOR antibodies, as well as age at disease onset, were as risk factors for the renal outcome.Conclusion: Anti-EPOR antibodies were associated with the progression of renal dysfunction in patients with AAV. 相似文献
994.
Tien Van Vu Velu Sivankalyani Eun‐Jung Kim Duong Thi Hai Doan Mil Thi Tran Jihae Kim Yeon Woo Sung Minwoo Park Yang Jae Kang Jae‐Yean Kim 《Plant biotechnology journal》2020,18(10):2133-2143
Genome editing via the homology‐directed repair (HDR) pathway in somatic plant cells is very inefficient compared with error‐prone repair by nonhomologous end joining (NHEJ). Here, we increased HDR‐based genome editing efficiency approximately threefold compared with a Cas9‐based single‐replicon system via the use of de novo multi‐replicon systems equipped with CRISPR/LbCpf1 in tomato and obtained replicon‐free but stable HDR alleles. The efficiency of CRISPR/LbCpf1‐based HDR was significantly modulated by physical culture conditions such as temperature and light. Ten days of incubation at 31 °C under a light/dark cycle after Agrobacterium‐mediated transformation resulted in the best performance among the tested conditions. Furthermore, we developed our single‐replicon system into a multi‐replicon system that effectively increased HDR efficiency. Although this approach is still challenging, we showed the feasibility of HDR‐based genome editing of a salt‐tolerant SlHKT1;2 allele without genomic integration of antibiotic markers or any phenotypic selection. Self‐pollinated offspring plants carrying the HKT1;2 HDR allele showed stable inheritance and germination tolerance in the presence of 100 mm NaCl. Our work may pave the way for transgene‐free editing of alleles of interest in asexually and sexually reproducing plants. 相似文献
995.
Vuong Quang Tran Thang Phan Quang Ohura Takeshi Choi Sung-Deuk 《Reviews in Environmental Science and Biotechnology》2020,19(2):259-273
Reviews in Environmental Science and Bio/Technology - Chlorinated and brominated polycyclic aromatic hydrocarbons (ClPAHs and BrPAHs, respectively) are a new derivative group of PAHs. These... 相似文献
996.
Ninh Khac Ban Vu Huong Giang Tran My Linh Le Quynh Lien Ninh Thi Ngoc Do Thi Thao Nguyen Hoai Nam Nguyen Xuan Cuong Phan Van Kiem Chau Van Minh 《Phytochemistry letters》2013,6(2):267-269
This work was done as a part of our ongoing projects to catalog the chemical constituents and biological activities of the Morinda species growing in Vietnam. Phytochemical investigations of the methanol extract of Morinda umbellata aerial parts resulted in the isolation of two new 11-noriridoids, umbellatolides A (1) and B (2). Their structures were elucidated by NMR (1H NMR, 13C NMR, HSQC, HMBC, 1H–1H COSY, and NOESY) and FTICRMS data. This is the first report of 11-noriridoids from M. umbellata. The cytotoxic activity and protective effect on oxidative stress injury stimulated by H2O2 in murine hepatocyte of 1 and 2 were also evaluated. 相似文献
997.
Bich Tran David C. Whiteman Penelope M. Webb Lin Fritschi Jonathan Fawcett Harvey A. Risch Robyn Lucas Nirmala Pandeya Annaka Schulte Rachel E. Neale 《Cancer epidemiology》2013,37(6):886-892
Background: Ecological studies showing an inverse association between pancreatic cancer incidence and mortality and levels of ultraviolet radiation (UVR), suggest that higher levels of sun exposure may reduce risks of pancreatic cancer but there has been only one individual-level study that examined this issue. We aimed to examine the association between pancreatic cancer and markers of exposure to solar UVR, namely skin type, treatment of skin lesions, ambient UVR and time outdoors on work days. Methods: We used data from an Australian case-control study. Location at birth, residential location during adulthood, outdoors work, history of skin lesion treatment and sensitivity of the skin to the sun were obtained by questionnaire. We limited the analyses to Caucasians who answered the questionnaire about UVR (controls = 589/711 recruited; cases = 496/705 recruited). We used NASA's Total Ozone Mapping Spectrometer to estimate ambient UVR. Results: Being born in or living in areas of higher ambient UVR (compared to lower ambient UVR) was associated with about 30–40% lower risk of pancreatic cancer. People with fair skin colour had 47% lower risk of pancreatic cancer than those with dark skin colour (95% CI 0.37–0.75). There was some suggestion of increased risk with increased average number of hours spent outside at work. Conclusions: This study suggests that people with light skin colour or those born or living in areas of high ambient UVR have lower risk of pancreatic cancer. Our analysis supports an association between UVR and pancreatic cancer, possibly mediated through production of vitamin D. 相似文献
998.
999.
Richelle C. Charles Tania Sultana Mohammad Murshid Alam Yanan Yu Ying Wu-Freeman Meagan Kelly Bufano Sean M. Rollins Lillian Tsai Jason B. Harris Regina C. LaRocque Daniel T. Leung W. Abdullah Brooks Tran Vu Thieu Nga Sabina Dongol Buddha Basnyat Stephen B. Calderwood Jeremy Farrar Farhana Khanam John S. Gunn Firdausi Qadri Stephen Baker Edward T. Ryan 《PLoS neglected tropical diseases》2013,7(8)
Background
Salmonella enterica serotype Typhi can colonize and persist in the biliary tract of infected individuals, resulting in a state of asymptomatic chronic carriage. Chronic carriers may act as persistent reservoirs of infection within a community and may introduce infection to susceptible individuals and new communities. Little is known about the interaction between the host and pathogen in the biliary tract of chronic carriers, and there is currently no reliable diagnostic assay to identify asymptomatic S. Typhi carriage.Methodology/Principal Findings
To study host-pathogen interactions in the biliary tract during S. Typhi carriage, we applied an immunoscreening technique called in vivo-induced antigen technology (IVIAT), to identify potential biomarkers unique to carriers. IVIAT identifies humorally immunogenic bacterial antigens expressed uniquely in the in vivo environment, and we hypothesized that S. Typhi surviving in the biliary tract of humans may express a distinct antigenic profile. Thirteen S. Typhi antigens that were immunoreactive in carriers, but not in healthy individuals from a typhoid endemic area, were identified. The identified antigens included a number of putative membrane proteins, lipoproteins, and hemolysin-related proteins. YncE (STY1479), an uncharacterized protein with an ATP-binding motif, gave prominent responses in our screen. The response to YncE in patients whose biliary tract contained S. Typhi was compared to responses in patients whose biliary tract did not contain S. Typhi, patients with acute typhoid fever, and healthy controls residing in a typhoid endemic area. Seven of 10 (70%) chronic carriers, 0 of 8 bile culture-negative controls (0%), 0 of 8 healthy Bangladeshis (0%), and 1 of 8 (12.5%) Bangladeshis with acute typhoid fever had detectable anti-YncE IgG in blood. IgA responses were also present.Conclusions/Significance
Further evaluation of YncE and other antigens identified by IVIAT could lead to the development of improved diagnostic assays to identify asymptomatic S. Typhi carriers. 相似文献1000.