全文获取类型
收费全文 | 227篇 |
免费 | 25篇 |
出版年
2024年 | 1篇 |
2023年 | 1篇 |
2022年 | 2篇 |
2021年 | 3篇 |
2020年 | 4篇 |
2019年 | 1篇 |
2018年 | 4篇 |
2017年 | 7篇 |
2016年 | 11篇 |
2015年 | 8篇 |
2014年 | 16篇 |
2013年 | 10篇 |
2012年 | 15篇 |
2011年 | 15篇 |
2010年 | 6篇 |
2009年 | 4篇 |
2008年 | 7篇 |
2007年 | 11篇 |
2006年 | 9篇 |
2005年 | 9篇 |
2004年 | 9篇 |
2003年 | 11篇 |
2002年 | 7篇 |
2001年 | 4篇 |
2000年 | 5篇 |
1999年 | 7篇 |
1998年 | 8篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1995年 | 9篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 5篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 5篇 |
1988年 | 1篇 |
1987年 | 5篇 |
1986年 | 3篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 3篇 |
1981年 | 2篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1968年 | 2篇 |
1965年 | 1篇 |
排序方式: 共有252条查询结果,搜索用时 734 毫秒
1.
2.
G Palka A Verrotti S Peca L Mosca G Lombardo M Verrotti G Morgese 《Annales de génétique》1986,29(1):55-58
A female infant with severe growth-weight retardation and with a ring chromosome 11, associated with trisomy X in 15% of metaphases, has been reported. A literature review of cases of r(11) shows that the clinical features of these patients, although showing different frequencies, are similar to those of the del(11q) syndrome. It has been suggested that the variability of the mental retardation in r(11) patients is attributable to the unstability of the ring and to the different break points in these two chromosomal rearrangements. The origin of the r(11) was also addressed by studying fragile sites of the parents at 11p15 and 11q25. 相似文献
3.
Mosca W 《Parasitology today (Personal ed.)》1986,2(4):122; author reply 122-122; author reply 123
4.
Mosca A D'Alagni M Del Prete R De Michele GP Summanen PH Finegold SM Miragliotta G 《Anaerobe》1995,1(1):21-24
In this study we describe two properties of the Gram-negative bacterium Bilophila wadsworthia, namely the ability to clot Limulus lysate and the capacity to induce the production of tissue factor-like procoagulant activity by human mononuclear cells in vitro. Although exhibited at a lower degree when compared with those of typical Gram-negative bacteria or Gram-negative endotoxin those activities may account in part for Bilophila's pathogenicity. The capacity indeed to induce fibrin formation through the interaction with mononuclear cells suggests one mechanism by which the microorganism might cause abscess formation in the host. Moreover, since this activity is dependent on the number of Bilophila interacting with mononuclear cells, we hypothesize that this biological activity is closely influenced by growth environment. 相似文献
5.
acta ethologica - Here, we describe the epimeletic behavior of an adult Risso’s dolphin towards a deceased newborn calf of the same species across several days with photographs, acoustic... 相似文献
6.
Variation in heat shock proteins within tropical and desert species of poeciliid fishes 总被引:8,自引:0,他引:8
Norris CE; diIorio PJ; Schultz RJ; Hightower LE 《Molecular biology and evolution》1995,12(6):1048-1062
The 70-kilodalton heat shock protein (hsp70) family of molecular
chaperones, which contains both stress-inducible and normally abundant
constitutive members, is highly conserved across distantly related taxa.
Analysis of this protein family in individuals from an outbred population
of tropical topminnows, Poeciliopsis gracilis, showed that while
constitutive hsp70 family members showed no variation in protein isoforms,
inducibly synthesized hsp70 was polymorphic. Several species of
Poeciliopsis adapted to desert environments exhibited lower levels of
inducible hsp70 polymorphism than the tropical species, but constitutive
forms were identical to those in P. gracilis, as they were in the
confamilial species Gambusia affinis. These differences suggest that
inducible and constitutive members of this family are under different
evolutionary constraints and may indicate differences in their function
within the cell. Also, northern desert species of Poeciliopsis synthesize a
subset of the inducible hsp70 isoforms seen in tropical species. This
distribution supports the theory that ancestral tropical fish migrated
northward and colonized desert streams; the subsequent decrease in
variation of inducible hsp70 may have been due to genetic drift or a
consequence of adaptation to the desert environment. Higher levels of
variability were found when the 30- kilodalton heat shock protein (hsp30)
family was analyzed within different strains of two desert species of
Poeciliopsis and also in wild-caught individuals of Gambusia affinis. In
both cases the distribution of hsp30 isoform diversity was similar to that
seen previously with allozyme polymorphisms.
相似文献
7.
Ecologic and hygienic interests led us to analyze the mycoflora of the sands of a sand box for children's play in Turin.Along with traditional methods, we have also employed selective techniques suitable for the isolation of cellulolytic and keratinolytic fungi.A total of 89 species were isolated. As supported by the literature references, the presence of most species is justified by the exogenous supply of vegetal residues, hairs, feathers and excrements. A good deal of species, moreover, are either well known agents of mycoses or have been isolated from various animal and human lesions; thus these sands do not represent the ideal environment for children's play.Work n. 253 performed under the auspices of the Centro di Studio sulla Micologia del Terreno del C.N.R. at the Istituto Botanico dell'Università di Torino. 相似文献
8.
Control of cell volume in the J774 macrophage by microtubule disassembly and cyclic AMP 总被引:8,自引:5,他引:3
下载免费PDF全文
![点击此处可从《The Journal of cell biology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
We have explored the possibilities that cell volume is regulated by the status of microtubule assembly and cyclic AMP metabolism and may be coordinated with shape change. Treatment of J774.2 mouse macrophages with colchicine caused rapid microtubule disassembly and was associated with a striking increase (from 15-20 to more than 90 percent) in the proportion of cells with a large protuberance at one pole. This provided a simple experimental system in which shape changes occurred in virtually an entire cell population in suspension. Parallel changes in cell volume could then be quantified by isotope dilution techniques. We found that the shape change caused by colchicine was accompanied by a decrease in cell volume of approximately 20 percent. Nocodozole, but not lumicolchicine, caused identical changes in both cell shape and cell volume. The volume loss was not due to cell lysis nor to inhibition of pinocytosis. The mechanism of volume loss was also examined. Colchicine induced a small but reproducible increase in activity of the ouabain-sensitive Na(+), K(+)-dependent ATPase. However, inhibition of this enzyme/transport system by ouabain did not change cell volume nor did it block the colchicines-induced decrease in volume. One the other hand, SITS (4’acetamido, 4-isothiocyano 2,2’ disulfonic acid stilbene), an inhibitor of anion transport, inhibited the effects of colchicines, thus suggesting a role for an anion transport system in cell volume regulation. Because colchicine is known to activate adenylate cyclase in several systems and because cell shape changes are often induced by hormones that elevate cyclic AMP, we also examined the effects of cyclic AMP on cell volume. Agents that act to increase syclic AMP (cholera toxin, which activates adenylate cyclase; IBMX, and inhibitor of phosphodiesterase; and dibutyryl cyclic AMP) all caused a volume decrease comparable to that of colchicine. To define the effective metabolic pathway, we studied two mutants of J774.2, one deficient in adenylate cyclase and the other exhibiting markedly reduced activity of cyclic AMP-dependent protein kinase. Cholera toxin did not produce a volume change in either mutant. Cyclic AMP produced a decrease in the cyclase-deficient line comparable to that in wild type, but did not cause a volume change in the kinase- deficient line. This analysis established separate roles for cyclic AMP and colchicine. The volume decrease induced by cyclic AMP requires the action of a cyclic AMP-dependent protein kinase. Colchicine, on the other hand, induced a comparable volume change in both mutants and wild type, and thus does not require the kinase. 相似文献
9.
M A Rosei L Mosca C De Marco 《Biochemical and biophysical research communications》1992,184(3):1190-1196
Leu-enkephalin and Met-enkephalin are oxidized in vitro by mushroom and sepia tyrosinase giving rise to synthetic melanins whose production is dependent on incubation time and on enzyme concentration. The Enk-melanins formed are acid-insoluble brownish or reddish pigments showing a continuous absorbance in the visible region when dissolved in basic solution. The presence of the amino acid chain makes them fully soluble in pH 7.4 0.05 M phosphate buffer and methanol. 相似文献
10.