全文获取类型
收费全文 | 113篇 |
免费 | 26篇 |
国内免费 | 1篇 |
专业分类
140篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 1篇 |
2019年 | 2篇 |
2018年 | 7篇 |
2017年 | 4篇 |
2016年 | 6篇 |
2015年 | 4篇 |
2014年 | 10篇 |
2013年 | 4篇 |
2012年 | 5篇 |
2011年 | 5篇 |
2010年 | 4篇 |
2009年 | 4篇 |
2008年 | 9篇 |
2007年 | 8篇 |
2006年 | 2篇 |
2005年 | 4篇 |
2003年 | 4篇 |
2002年 | 2篇 |
2001年 | 2篇 |
2000年 | 4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 |
1992年 | 4篇 |
1991年 | 4篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1988年 | 5篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 5篇 |
1984年 | 2篇 |
1983年 | 4篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有140条查询结果,搜索用时 15 毫秒
51.
BOLA‐DRB3 gene polymorphisms influence bovine leukaemia virus infection levels in Holstein and Holstein × Jersey crossbreed dairy cattle 下载免费PDF全文
H. A. Carignano M. J. Beribe M. E. Caffaro A. Amadio J. P. Nani G. Gutierrez I. Alvarez K. Trono M. M. Miretti M. A. Poli 《Animal genetics》2017,48(4):420-430
Bovine leukemia virus (BLV) infections, causing persistent lymphocytosis and lethal lymphosarcoma in cattle, have reached high endemicity on dairy farms. We observed extensive inter‐individual variation in the level of infection (LI) by assessing differences in proviral load in peripheral blood. This phenotypic variation appears to be determined by host genetics variants, especially those located in the BoLA‐DRB3 MHCII molecule. We performed an association study using sequencing‐based typed BOLA‐DRB3 alleles from over 800 Holstein and Holstein × Jersey cows considering LI in vivo and accounting for filial relationships. The DBR3*0902 allele was associated with a low level of infection (LLI) (<1% of circulating infected B‐cells), whereas the DRB3*1001 and DRB3*1201 alleles were related to a high level of infection (HLI). We found evidence that 13 polymorphic positions located in the pockets of the peptide‐binding cleft of the BOLA‐DRB3 alleles were associated with LI. DRB3*0902 had unique haplotypes for each of the pockets: Ser13‐Glu70‐Arg71‐Glu74 (pocket 4), Ser11‐Ser30 (pocket 6), Glu28‐Trp61‐Arg71 (pocket 7) and Asn37‐Asp57 (pocket 9), and all of them were significantly associated with LLI. Conversely, Lys13‐Arg70‐Ala71‐Ala74 and Ser13‐Arg70‐Ala71‐Ala74, corresponding to the DRB3*1001 and *1201 alleles respectively, were associated with HLI. We showed that the specific amino acid pattern in the DRB3*0902 peptide‐binding cleft may be related to the set point of a very low proviral load level in adult cows. Moreover, we identified two BOLA‐DRB3 alleles associated with a HLI, which is compatible with a highly contagious profile. 相似文献
52.
Olli Salmi Janne Hukkinen Jyrki Heino Nani Pajunen Maaria Wierink 《Journal of Industrial Ecology》2012,16(1):119-128
Many scholars of industrial ecology have focused on the institutional and organizational challenges of building and maintaining regional industrial symbiosis through the synergistic integration of material and energy flows. Despite the promise that these intellectual developments hold for the future dematerialization of industrial production, they rarely address the actual regulatory obstacles of turning wastes into raw materials. In this article we introduce a potential future industrial symbiosis around the Gulf of Bothnia between Finland and Sweden, and assess the regulatory bottlenecks related to waste by‐product consideration. We find that although the Gulf of Bothnia region has technological and economic potential for industrial symbiosis, the regulatory support for this is insufficient. We suggest a common pool resource‐based governance system that could utilize market and regulatory mechanisms in a regional‐level cross‐border system of governance. Importantly, the suggested governance system would protect the users of potential raw materials from unpredictable waste regulation, market risks related to large‐scale material flows, and societal risks of hazardous waste treatment. 相似文献
53.
Claudia Maria Lincoln Silva Fred Bernardes Filho Glauber Voltan Jaci Maria Santana Marcel Nani Leite Filipe Rocha Lima Luisiane de Avila Santana Natlia Aparecida de Paula Patricia Toscano Barreto Nogueira Onofre Wilson Marques-Junior Vanessa Aparecida Tomaz Carmem Sílvia Vilela Pinese Marco Andrey Cipriani Frade 《PLoS neglected tropical diseases》2021,15(8)
54.
Subtropical streams harbour higher genus richness and lower abundance of insects compared to boreal streams,but scale matters 下载免费PDF全文
55.
Maura Porta Paula L. Diaz-Sylvester Alma Nani Julio A. Copello 《生物化学与生物物理学报:生物膜》2008,1778(11):2469-2479
Ca2+-entry via L-type Ca2+ channels (DHPR) is known to trigger ryanodine receptor (RyR)-mediated Ca2+-release from sarcoplasmic reticulum (SR). The mechanism that terminates SR Ca2+ release is still unknown. Previous reports showed evidence of Ca2+-entry independent inhibition of Ca2+ sparks by DHPR in cardiomyocytes. A peptide from the DHPR loop II-III (PepA) was reported to modulate isolated RyRs. We found that PepA induced voltage-dependent “flicker block” and transition to substates of fully-activated cardiac RyRs in planar bilayers. Substates had less voltage-dependence than block and did not represent occupancy of a ryanoid site. However, ryanoids stabilized PepA-induced events while PepA increased RyR2 affinity for ryanodol, which suggests cooperative interactions. Ryanodol stabilized Imperatoxin A (IpTxA) binding but when IpTxA bound first, it prevented ryanodol binding. Moreover, IpTxA and PepA excluded each other from their sites. This suggests that IpTxA generates a vestibular gate (either sterically or allosterically) that prevents access to the peptides and ryanodol binding sites. Inactivating gate moieties (“ball peptides”) from K+ and Na+ channels (ShakerB and KIFMK, respectively) induced well resolved slow block and substates, which were sensitive to ryanoids and IpTxA and allowed, by comparison, better understanding of PepA action. The RyR2 appears to interact with PepA or ball peptides through a two-step mechanism, reminiscent of the inactivation of voltage-gated channels, which includes binding to outer (substates) and inner (block) vestibular regions in the channel conduction pathway. Our results open the possibility that “ball peptide-like” moieties in RyR2-interacting proteins could modulate SR Ca2+ release in cells. 相似文献
56.
Oili A. Hietala Anitta E. Pulkka Seppo P. Lapinjoki Päivi H. Laitinen Antti E. I. Pajunen 《Journal of neurochemistry》1983,41(3):801-808
Abstract: Effects of intracerebroventricularly injected methylglyoxal bis(guanylhydrazone) on polyamine metabolism in mouse brain were recorded during 180 h after a single dose of 3.4 μmol/kg body weight. Cerebral concentrations of 31 other amino compounds were also asayed during the experiment. The drug caused a significant inhibition of adenosylmethionine decarboxylase that lasted for 50 h, with the maximal decrease, about 70%, occurring between 5 and 10 h after injection. Significant decreases of brain spermidine and spermine concentrations were observed in three phases. Two transient decreases occurred at 10 and at 35 h, and a longer-lasting one between 60 and 100 h. Ornithine decarboxylase was stimulated within 5 h after the injection, reaching a maximal level about 30-fold above normal at 60 h, and returned to control level at 140 h. This stimulation was accompanied by significant accumulation of the reaction product, putrescine, in the brain. It was maximally > 10-fold above normal at 160 h, and was still significantly above control at the end of the observation period. The time course of changes in the parameters of polyamine metabolism was regarded as support of a previously presented hypothesis that limiting putrescine concentration may play a role in the regulation of cerebral polyamine metabolism. In addition, the present results emphasize the possibility that changes in the activities of catabolic reactions may also contribute to the regulation of cerebral polyamine concentrations. Of the 31 amino compounds analyzed, only the concentrations of ornithine, urea, glutamine, and glutamate showed significant changes from normal. Ornithine concentration first was significantly increased at 25 h, whereafter it decreased and was somewhat below normal for most of the period between 60 and 180 h. The urea concentration showed a tendency to increase throughout the experiment, being significantly elevated at the end. These changes were regarded as suggesting that the increased need for ornithine in putrescine synthesis is satisfied mainly by increased arginine uptake and degradation. The magnitude of urea accumulation suggested that metabolism of ornithine to glutamate was also accelerated. An unexpected shift toward glutamine in the glutamine/glutamate relationship was observed during the first 100 h. However, the total concentration of these two compounds was quite constant throughout the experiment. Inhibition of ornithine decarboxylase by intraventricular injection of 2-difluoromethylornithine was tried during the study, but sufficient doses could not be used without induction of acute side effects. 相似文献
57.
Hibernation pattern in the garden dormouse (Eliomys quercinus) was studied at TA's of 0, 4, 6.5, and 9 degrees C during 6 months in each study winter. The animals were kept in darkness without food or water. Body temperature and the mean duration of the hibernation periods were ambient temperature dependent. The comparison of hibernation at different TA's was based on three features: the mean duration of the hibernation periods during the midwinter plateau, the existence of the initial and terminal phases with the changing length of the hibernation periods, and the differences between the sexes. The TA of 4 degrees C was the optimal TA for long-term hibernation. The difference between 4 degrees C and other TA's was greater in males. The TA's of 0 and 9 degrees C were near the lower and higher TA limits for long-term hibernation. Signs of the existence of a circannual rhythm were detected in the males toward the end of the hibernation season. 相似文献
58.
A human-mouse hybrid, DUR 4 (Solomon et al., 1976), containing a human X/15 translocation chromosome and also chromosome 5, among other human chromosomes, was used in a double selection system to obtain hybrids of four different types: X/15+ 5+, X/15- 5+, X/15+, 5-. Standard positive and negative selection systems were used for the X chromosome, and negative selection for chromosome 5 was done with diphtheria toxin. The assignment of HEXB and presently only when both the X/15 chromosome and chromosome 5 were present. A "HEXA-like" band segregated with chromosome 15 (or X/15) but independently of chromosome 5. This component, unlike HEXA, does not contain human HEXbeta antigen. 相似文献
59.
Jaepyeong Cha Roger R. Nani Michael P. Luciano Gabriel Kline Aline Broch Kihoon Kim Jung-Man Namgoong Rhushikesh A. Kulkarni Jordan L. Meier Peter Kim Martin J. Schnermann 《Bioorganic & medicinal chemistry letters》2018,28(16):2741-2745
Surgical methods guided by exogenous fluorescent markers have the potential to define tissue types in real time. Small molecule dyes with efficient and selective renal clearance could enable visualization of the ureter during surgical procedures involving the abdomen and pelvis. These studies report the design and synthesis of a water soluble, net neutral C4′-O-alkyl heptamethine cyanine, Ureter-Label (UL)-766, with excellent properties for ureter visualization. This compound is accessed through a concise synthetic sequence involving an N- to O-transposition reaction that provides other inaccessible C4′-O-alkyl heptamethine cyanines. Unlike molecules containing a C4′-O-aryl substituent, which have also been used for ureter visualization, UL-766 is not reactive towards glutathione and the cellular proteome. In addition, rat models of abdominal surgery reveal that UL-766 undergoes efficient and nearly exclusive renal clearance in vivo. In total, this molecule represents a promising candidate for visualizing the ureter during a variety of surgical interventions. 相似文献
60.
L Pajunen T A Jones A Goddard D Sheer E Solomon T Pihlajaniemi K I Kivirikko 《Cytogenetics and cell genetics》1991,56(3-4):165-168
Prolyl 4-hydroxylase, an alpha 2 beta 2 tetramer, catalyzes the formation of 4-hydroxyproline in collagens and related proteins by hydroxylating proline residues in peptide linkages. The beta-subunit of prolyl 4-hydroxylase (P4HB) is a highly unusual multifunctional polypeptide that is identical to the enzyme protein disulfide isomerase and a major cellular thyroid hormone-binding protein and is highly similar to a glycosylation site-binding polypeptide of oligosaccharyl transferase. We report here the regional assignment of the gene for this multifunctional polypeptide. In situ hybridization mapped the gene to 17q25. Southern blot analyses of restricted DNA from a chromosome-mediated gene transfer transfectant panel suggested that the P4HB gene is located distal to the gene for thymidine kinase, either between the genes for thymidine kinase and galactokinase or on the telomeric side of both these genes. 相似文献