全文获取类型
收费全文 | 284篇 |
免费 | 6篇 |
出版年
2022年 | 3篇 |
2021年 | 3篇 |
2019年 | 3篇 |
2018年 | 9篇 |
2017年 | 4篇 |
2016年 | 4篇 |
2015年 | 5篇 |
2014年 | 8篇 |
2013年 | 8篇 |
2012年 | 9篇 |
2011年 | 8篇 |
2010年 | 11篇 |
2009年 | 7篇 |
2008年 | 15篇 |
2007年 | 16篇 |
2006年 | 8篇 |
2005年 | 4篇 |
2004年 | 11篇 |
2003年 | 14篇 |
2002年 | 8篇 |
2001年 | 14篇 |
2000年 | 10篇 |
1999年 | 5篇 |
1996年 | 3篇 |
1993年 | 3篇 |
1992年 | 9篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1989年 | 4篇 |
1988年 | 2篇 |
1987年 | 6篇 |
1986年 | 2篇 |
1985年 | 3篇 |
1983年 | 2篇 |
1981年 | 4篇 |
1979年 | 4篇 |
1978年 | 5篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 4篇 |
1974年 | 3篇 |
1973年 | 4篇 |
1972年 | 7篇 |
1971年 | 4篇 |
1970年 | 2篇 |
1969年 | 2篇 |
1968年 | 2篇 |
1967年 | 1篇 |
1966年 | 6篇 |
1965年 | 1篇 |
排序方式: 共有290条查询结果,搜索用时 15 毫秒
41.
42.
L. I. Kolesnikova M. A. Darenskaya L. V. Rychkova L. A. Grebenkina M. I. Dolgikh O. A. Gavrilova 《Journal of Evolutionary Biochemistry and Physiology》2018,54(5):356-362
The indicators of lipid metabolism were analyzed comparatively in 258 adolescent girls and boys representing major ethnic groups of Eastern Siberia: indigenous Tofalars, Evenks and Buryats and alien Europoids (Caucasoids). The adolescent lipid profile in these groups was found to be ethnos-specific. In contemporary Tofalars and Buryats, its indicators are stable, while the overall lipid profile shows an anti-atherogenic trend. By contrast, Evenks and Europoids show an increasing level of cholesterol-containing blood components. 相似文献
43.
Abstract: Many articulated brachiopods experience marked life habit variations during ontogeny because they experience their fluid environment at successively higher Reynolds numbers, and they can change the configuration of their inhalant and exhalant flows as body size increases. We show that the extant brachiopod Terebratalia transversa undergoes a substantial ontogenetic change in reorientation governed by rotation around the pedicle. T. transversa′s reorientation angle (maximum ability to rotate on the pedicle) decreases during ontogeny, from 180 degrees in juveniles to 10–20 degrees in individuals exceeding 5 mm, to complete cessation of rotation in individuals larger than 10 mm. Rotation ability is substantially reduced after T. transversa achieves the adult lophophore configuration and preferred orientation with respect to ambient water currents at a length of 2.5–5 mm. We hypothesize that the rotation angle of T. transversa is determined mainly by the position of ventral and dorsal points of attachment of dorsal pedicle muscles relative to the pedicle. T. transversa shows a close correlation between the ontogenetic change in reorientation angle and ontogeny of morphological traits that are related to points of attachment of dorsal pedicle muscles, although other morphological features can also limit rotation in the adult stage. The major morphological change in cardinalia shape and the observed reduction of rotation affect individuals 2.5–10 mm in length. The position of ventral insertions of dorsal pedicle muscles remains constant, but contraction of dorsal pedicle muscles is functionally handicapped because dorsal insertions shift away from the valve midline, rise above the dorsal valve floor, and become limited by a wide cardinal process early in ontogeny (<5 mm). The rate of increase of cardinal process width and of distance between dorsal pedicle muscle scars substantially decreases in the subadult stage (5–10 mm), and most of the cardinalia shell traits grow nearly isometrically in the adult stage (>10 mm). T. transversa attains smaller shell length in crevices than on exposed substrates. The proportion of small‐sized individuals and population density is lower on exposed substrates than in crevices, indicating higher juvenile mortality on substrates prone to grazing and physical disturbance. The loss of reorientation ability can be a consequence of morphological changes that strengthen substrate attachment and maximize protection against biotic or physical disturbance (1) by minimizing torques around the pedicle axis and/or (2) by shifting energy investments into attachment strength at the expense of the cost involved in reorientation. 相似文献
44.
I. N. Anisimova L. G. Tumanova V. A. Gavrilova A. V. Dyagileva L. I. Pasha V. A. Mitin G. I. Timofeyeva 《Russian Journal of Genetics》2009,45(8):934-943
The expression of genomic instability was studied at the phenotypical (morphological characters, electrophoretic spectra of
seed storage proteins) and molecular (DNA amplification products) levels in interspecific hybrids (ISHs) from crosses of inbred
lines of cultivated sunflower Helianthus annuus with perennial species of the genus Helianthus and in introgressive lines (ILs) produced on their basis. Unstable state of the locus determining the trait of lower branching
was proved by the method of hybridological analysis. It was shown with the use of RAPD markers that the IL genome is characterized
by instability even after long-term inbreeding (in generations F8-F12). In progenies of different combinations of interspecific crosses, identical polymorphic variants were revealed for a seed
storage protein, helianthinin, and for DNA fragments homologous to structural genes of functionally important proteins, suggesting
the nonrandom character of ISH genome variation. This variation may be determined by genome reorganizations under the action
of a genome shock induced by interspecific hybridization. The factors inducing reorganizations in the genome include the activity
of mobile genetic elements (MGEs). Using primers specific to different MGE families, nucleotide sequences with a high level
of homology to the sequences of fragments of the mobile elements MuDR, Far1, CACTA, Stowaway, and Tourist were identified
in the sunflower genome. The possibility of using MGE fragments for sunflower genotyping was demonstrated. 相似文献
45.
Junghyo Jo Oksana Gavrilova Stephanie Pack William Jou Shawn Mullen Anne E. Sumner Samuel W. Cushman Vipul Periwal 《PLoS computational biology》2009,5(3)
Adipose tissue grows by two mechanisms: hyperplasia (cell number increase) and hypertrophy (cell size increase). Genetics and diet affect the relative contributions of these two mechanisms to the growth of adipose tissue in obesity. In this study, the size distributions of epididymal adipose cells from two mouse strains, obesity-resistant FVB/N and obesity-prone C57BL/6, were measured after 2, 4, and 12 weeks under regular and high-fat feeding conditions. The total cell number in the epididymal fat pad was estimated from the fat pad mass and the normalized cell-size distribution. The cell number and volume-weighted mean cell size increase as a function of fat pad mass. To address adipose tissue growth precisely, we developed a mathematical model describing the evolution of the adipose cell-size distributions as a function of the increasing fat pad mass, instead of the increasing chronological time. Our model describes the recruitment of new adipose cells and their subsequent development in different strains, and with different diet regimens, with common mechanisms, but with diet- and genetics-dependent model parameters. Compared to the FVB/N strain, the C57BL/6 strain has greater recruitment of small adipose cells. Hyperplasia is enhanced by high-fat diet in a strain-dependent way, suggesting a synergistic interaction between genetics and diet. Moreover, high-fat feeding increases the rate of adipose cell size growth, independent of strain, reflecting the increase in calories requiring storage. Additionally, high-fat diet leads to a dramatic spreading of the size distribution of adipose cells in both strains; this implies an increase in size fluctuations of adipose cells through lipid turnover. 相似文献
46.
Margalit Goldgof Cuiying Xiao Tatyana Chanturiya William Jou Oksana Gavrilova Marc L. Reitman 《The Journal of biological chemistry》2014,289(28):19341-19350
The chemical uncoupler 2,4-dinitrophenol (DNP) was an effective and widely used weight loss drug in the early 1930s. However, the physiology of DNP has not been studied in detail because toxicity, including hyperthermia and death, reduced interest in the clinical use of chemical uncouplers. To investigate DNP action, mice fed a high fat diet and housed at 30 °C (to minimize facultative thermogenesis) were treated with 800 mg/liter DNP in drinking water. DNP treatment increased energy expenditure by ∼17%, but did not change food intake. DNP-treated mice weighed 26% less than controls after 2 months of treatment due to decreased fat mass, without a change in lean mass. DNP improved glucose tolerance and reduced hepatic steatosis without observed toxicity. DNP treatment also reduced circulating T3 and T4 levels, Ucp1 expression, and brown adipose tissue activity, demonstrating that DNP-mediated heat generation substituted for brown adipose tissue thermogenesis. At 22 °C, a typical vivarium temperature that is below thermoneutrality, DNP treatment had no effect on body weight, adiposity, or glucose homeostasis. Thus, environmental temperature should be considered when assessing an anti-obesity drug in mice, particularly agents acting on energy expenditure. Furthermore, the beneficial effects of DNP suggest that chemical uncouplers deserve further investigation for the treatment of obesity and its comorbidities. 相似文献
47.
48.
V G Vladimirov Iu E Strel'nikov S V Amosova G M Gavrilova V I Gostevskaia A S Petrov L A Sharova 《Radiobiologiia》1990,30(1):69-75
A new group of radioprotective agents, dimethylaminodithiazines, was discovered. The agents are effective when used in relatively small amounts and exert a radioprotective effect rapidly with both intraperitoneal and per os injections. The role of inhibition of oxidative processes and DNA biosynthesis in the mechanism of radioprotective action of dimethylaminodithiazines is discussed. 相似文献
49.
I. A. Ratnikova N. N. Gavrilova K. Bayakyshova Z. Zh. Turlybaeva L. A. Kosheleva N. M. Utegenova 《Biology Bulletin》2018,45(2):155-159
Strains of lactic acid and propionic acid bacteria and the A-5 bacterial association composed of the Lactobacillus brevis B-3/A-26, L. plantarum 2v/А-6, L. plantarum 14d/I, and Propionibacterium shermanii 2/10 cultures in equal proportion exhibiting high antitumor activity have been selected using the fungus Fusarium bulbigenum var. blasticola tumorlike growth model. L. acidophilus 27w, L. plantarum 2v/I, 2v/A-6, and 22A-310, L. fermentum 127A-4, L. cellobiosus 7n, L. salivarius 39n, P. shermanii 2/10, and the А-5 association were shown to inhibit completely the tumorlike growth of the fungus when present as 2% native cultures in the nutrient medium. The high antitumor activity of the A-5 association comparable with that of the therapeutic agents doxorubicin and cyclophosphamide was confirmed using human tumor cell lines originating from different organs (HepG2, RD, and H9). It has been demonstrated that the bacterial strains comprising the A-5 association were resistant to doxorubicin and methotrexate, the antitumor drugs tested. 相似文献
50.
Spectrophotometric study was carried out of the effect of medium polarity on the parabenzoquinone photooxidation of chlorophyll "a" at lower temperature using as solvents toluene and CCl4 containing different quantities of polaric solvents, methanole, ethanole, amilic alkohol, acetone. It is shown that the photoreaction with the formation of primary photooxidized form of the pigment starts only if some amount of the polar component is in the medium. The data are in favour of the suggestion that chlorophyll and quinone in non-polar medium form an reaction complex which disintegrates under the given conditions at a definite value of medium polarity. 相似文献