全文获取类型
收费全文 | 195篇 |
免费 | 8篇 |
国内免费 | 4篇 |
专业分类
207篇 |
出版年
2022年 | 6篇 |
2021年 | 15篇 |
2020年 | 6篇 |
2019年 | 7篇 |
2018年 | 3篇 |
2017年 | 5篇 |
2016年 | 7篇 |
2015年 | 14篇 |
2014年 | 10篇 |
2013年 | 21篇 |
2012年 | 17篇 |
2011年 | 18篇 |
2010年 | 9篇 |
2009年 | 9篇 |
2008年 | 7篇 |
2007年 | 15篇 |
2006年 | 7篇 |
2005年 | 4篇 |
2004年 | 3篇 |
2003年 | 1篇 |
2002年 | 3篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1971年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有207条查询结果,搜索用时 0 毫秒
101.
Sonboli A Mirjalili MH Hadian J Ebrahimi SN Yousefzadi M 《Zeitschrift für Naturforschung. C, Journal of biosciences》2006,61(9-10):677-680
The chemical composition of the essential oil obtained from the aerial flowering parts of Ziziphora clinopodioides subsp. bungeana (Juz.) Rech. f. was analyzed by GC and GC-MS. Thirty-two components representing 97.1% of the total oil were identified. Oxygenated monoterpenes (94.3%) were the predominant fraction of the oil with pulegone (65.2%), isomenthone (11.9%), 1,8-cineole (7.8%) and piperitenone (6.5%) as the main constituents. Antibacterial activity of the oil and also its two main components (pulegone and 1,8-cineole) were tested against seven bacteria. It was found that the oil exhibited interesting antibacterial activity against Staphylococcus epidermidis, S. aureus, Escherichia coli and Bacillus subtilis with MIC values of 3.75 mg/ml. 相似文献
102.
VGLUT2-dependent glutamate release from nociceptors is required to sense pain and suppress itch 总被引:1,自引:0,他引:1
Itch can be suppressed by painful stimuli, but the underlying neural basis is unknown. We generated conditional null mice in which vesicular glutamate transporter type 2 (VGLUT2)-dependent synaptic glutamate release from mainly Nav1.8-expressing nociceptors was abolished. These mice showed deficits in pain behaviors, including mechanical pain, heat pain, capsaicin-evoked pain, inflammatory pain, and neuropathic pain. The pain deficits were accompanied by greatly enhanced itching, as suggested by (1) sensitization of both histamine-dependent and histamine-independent itch pathways and (2) development of spontaneous scratching and skin lesions. Strikingly, intradermal capsaicin injection promotes itch responses in these mutant mice,?as opposed to pain responses in control littermates. Consequently, coinjection of capsaicin was no longer able to mask itch evoked by pruritogenic compounds. Our studies suggest that synaptic glutamate release from a group of peripheral nociceptors is required to sense pain and suppress itch. Elimination of VGLUT2 in these nociceptors creates a mouse model of chronic neurogenic itch. 相似文献
103.
Proteomics research routinely involves identifying peptides and proteins via MS/MS sequence database search. Thus the database search engine is an integral tool in many proteomics research groups. Here, we introduce the Comet search engine to the existing landscape of commercial and open‐source database search tools. Comet is open source, freely available, and based on one of the original sequence database search tools that has been widely used for many years. 相似文献
104.
105.
Dilfaraz Khan Hidayat Ullah Khan Farmanullah Khan Shafiullah Khan Syed Badshah Abdul Samad Khan Abdul Samad Farman Ali Ihsanullah Khan Nawshad Muhammad 《PloS one》2014,9(4)
A phytochemical investigation on the ethyl acetate soluble fraction of Lonicera quinquelocularis (whole plant) led to the first time isolation of one new phthalate; bis(7-acetoxy-2-ethyl-5-methylheptyl) phthalate (3) and two new benzoates; neopentyl-4-ethoxy-3, 5-bis (3-methyl-2-butenyl benzoate (4) and neopentyl-4-hydroxy-3, 5-bis (3-methyl-2-butenyl benzoate (5) along with two known compounds bis (2-ethylhexyl phthalate (1) and dioctyl phthalate (2). Their structures were established on the basis of spectroscopic analysis and by comparison with available data in the literature. All the compounds (1–5) were tested for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities in dose dependent manner. The IC50 (50% inhibitory effect) values of compounds 3 and 5 against AChE were 1.65 and 3.43 µM while the values obtained against BChE were 5.98 and 9.84 µM respectively. Compounds 2 and 4 showed weak inhibition profile. 相似文献
106.
Gheisari Y Ahmadbeigi N Naderi M Nassiri SM Nadri S Soleimani M 《Cell biology international》2011,35(3):209-213
Paracrine secretion of mediators may be the main route by which stem cells protect against injuries. Stem cells commonly secrete different bioactive molecules. In this study, we examined the hypothesis that administration of conditioned media of stem cells can diminish the burden of kidney injury. A mouse model of cisplatin-induced nephropathy was developed to test the putative renoprotective effects of conditioned media of human umbilical cord blood USSCs (unrestricted somatic stem cells) as well as mouse bone marrow MSCs (mesenchymal stem cells). None of these two types of conditioned medium could protect against kidney failure in terms of serum urea and creatinine, histopathologic examinations and physical activity score. Neither MSC- nor USSC-conditioned media were effective in protecting against kidney injury in our study. Possible explanations for our observations are offered, and related literature is reviewed. 相似文献
107.
Shirin T Rahman A Danielsson Å Uddin T Bhuyian TR Sheikh A Qadri SS Qadri F Hammarström ML 《Microbes and infection / Institut Pasteur》2011,13(12-13):1111-1120
Patients with acute watery diarrhea caused by Vibrio cholerae O1 or enterotoxigenic Escherichia coli (ETEC) were analyzed for innate immune factors produced by the epithelium during the disease process. Duodenal biopsies were obtained from study participants at the acute (day 2) and convalescent (day 21) stages of disease. Levels of α-defensin (HD-5 and -6), β-defensin (hBD-1-4), and cathelicidin (LL-37) mRNAs were determined by real-time qRT-PCR. hBD-2, HD-5, LL-37 peptides were analyzed in duodenal epithelium by immunomorphometry. Concentration of hBD-2 in stool was determined by ELISA. Specimens from healthy controls were also analyzed. hBD-2 mRNA levels were significantly increased at acute stage of diarrhea; hBD-2 peptide was detected in fecal specimens but barely in duodenal epithelium at acute stage. Immunomorphometry analysis showed that Paneth cells contain significantly higher amounts of HD-5 pre/propeptide at convalescence (P<0.01) and in healthy controls (P<0.001) compared to acute stage, LL-37 peptide levels also decreased at acute stage while mRNA levels remained unchanged. mRNA expression levels of the other antimicrobial peptides remained unchanged with higher levels of α-defensins than β-defensins. V. cholerae induced an innate immune response at the acute stage of disease characterized by increased expression of hBD-2, and continued expression of hBD-1, HD-5-6, and LL-37. 相似文献
108.
109.
Dharni S Alam M Kalani K Abdul-Khaliq Samad A Srivastava SK Patra DD 《Journal of microbiology and biotechnology》2012,22(5):674-683
A new strain, SD12, was isolated from tannery waste polluted soil and identified as Pseudomonas aeruginosa on the basis of phenotypic traits and by comparison of 16S rRNA sequences. This bacterium exhibited broad-spectrum antagonistic activity against phytopathogenic fungi. The strain produced phosphatases, cellulases, proteases, pectinases, and HCN and also retained its ability to produce hydroxamate-type siderophore. A bioactive metabolite was isolated from P. aeruginosa SD12 and was characterized as 1-hydroxyphenazine ((1-OH-PHZ) by nuclear magnetic resonance (NMR) spectral analysis. The strain was used as a biocontrol agent against root rot and wilt disease of pyrethrum caused by Rhizoctonia solani. The stain is also reported to increase the growth and biomass of Plantago ovata. The purified compound, 1-hydroxyphenazine, also showed broad-spectrum antagonistic activity towards a range of phytopathogenic fungi, which is the first report of its kind. 相似文献
110.
Dobrzanski MJ Rewers-Felkins KA Samad KA Quinlin IS Phillips CA Robinson W Dobrzanski DJ Wright SE 《Cancer immunology, immunotherapy : CII》2012,61(6):839-854
Adoptive T cell therapy for cancer patients optimally requires participation of CD4 T cells. In this phase I/II study, we assessed the therapeutic effects of adoptively transferred IL-10- and IFN-γ-producing CD4 effector cells in patients with recurrent ovarian cancer. Using MUC1 peptide and IL-2 for ex vivo CD4 effector cell generation, we show that three monthly treatment cycles of autologous T cell restimulation and local intraperitoneal re-infusion-modulated T cell-mediated immune responses that were associated with enhanced patient survival. One patient remains disease-free, another patient experienced prolonged survival for nearly 16?months with recurrent disease, and two patients expired within 3-5?months following final infusion. Prolonged survivors showed elevated levels of systemic CD3(+)CD4(+)CD25(+) and CD3(+)CD4(+)CD25(-) T cells when compared to that of pre-treatment levels and similarly treated short-term survivors. Such cell populations among these patients contained variable levels of "Inducible" Tr1 (CD4(+)CD25(-)FoxP3(-)IL-10(+)) and "Natural" (CD4(+)CD25(+)CD45RO(+)FoxP3(+)) TReg cell numbers and ratios that were associated with prolonged and/or disease-free survival. Moreover, peptide-restimulated T cells from these patients showed an elevation in both IFN-γ production, memory cell phenotype, and select TNF family ligands associated with enhanced T cell survival and apoptosis-inducing activities. This suggests that intraperitoneally administered Th1-like cells, producing elevated levels of IL-10, may require and/or induce differential levels of distinct systemic TReg subpopulations that influence, in part, long-term tumor immunity and enhanced memory/effector CD4-mediated therapeutic potentials. Furthermore, treatment efficacy and enhanced memory cell phenotype did not appear to be dependent on TReg cell numbers but upon ratios of "Inducible" and "Natural" TReg subpopulations. 相似文献