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61.
JA Nboyine S Boyer D Saville MJ Smith SD Wratten 《New Zealand journal of zoology.》2016,43(4):336-350
The endemic New Zealand ground wētā (Hemiandrus sp. ‘promontorius’) has a Naturally Uncommon conservation status. This is because of the paucity of information on its density and distribution. Here, the biology, density and distribution of a population of this wētā found in and around vineyards in the Awatere Valley, Marlborough was studied. Wētā density was assessed in vineyards, paddocks and shrublands in this valley. Soil moisture, penetration resistance, pH and organic matter were recorded at locations with and without wētā. Wētā density in vineyards was significantly higher than in either paddocks or shrub habitats. In vineyards, the density of this insect was significantly higher under-vines than in the inter-rows. Higher numbers of this wētā were found in moist soils that required lower force to burrow. Females laid an average of 55 eggs between March and April, which hatched in September. These findings highlight the intersection between agriculture and conservation. 相似文献
62.
Landi S Naccarati A Ross MK Hanley NM Dailey L Devlin RB Vasquez M Pegram RA DeMarini DM 《Mutation research》2003,538(1-2):41-50
Trihalomethanes (THMs) are disinfection by-products and suspected human carcinogens present in chlorinated drinking water. Previous studies have shown that many THMs induce sister chromatid exchanges and DNA strand breaks in human peripheral blood lymphocytes in vitro. Exposure to THMs occurs through oral, dermal, or inhalation routes, with the lung being a target of exposure by the latter route, although not a target for rodent carcinogenicity. Thus, to examine the genotoxicity of THMs in this tissue, we used the comet assay to examine the DNA damaging ability of five THMs in primary human lung epithelial cells. Cells were collected by scraping the large airways of four volunteers with a cytology brush and then passaging the cells no more than three times in order to have sufficient numbers for the experiments. Cells were exposed for 3h to 10, 100, or 1000 microM CHCl(3), CHCl(2)Br, CHClBr(2), or CHBr(3); CH(2)Cl(2) was also used as a model dihalomethane for comparison to the THMs. The compounds ranked as follows for DNA damaging ability: CHCl(2)Br>CHBr(3)>CHCl(3) approximately equal CH(2)Cl(2); CHClBr(2) was negative. Considerable inter-individual variation was observed. For example, CHCl(3) was genotoxic in only two subjects, and the interaction between dose and donor was highly significant (P<0.001). The same variation was observed for CHCl(2)Br, which was positive only in the two subjects in which CHCl(3) was negative. This variation was not due to the GSTT1-1 genotype of the subjects. Although two subjects were GSTT1-1(+), and two were GSTT1-1(-), no cultured cells with a GSTT1-1(+) genotype had detectable GSTT1-1 enzymatic activity nor did any frozen epithelial cells that had not been cultured. However, GSTT1-1 enzymatic activity was detected in fresh (neither frozen nor cultured) lung cells. These results show that freezing or culturing causes lung cells to lose GSTT1-1 activity and that factors other than GSTT1-1 activity play a role in the variable responses of these human cells to the genotoxicity of the halomethanes studied here. 相似文献
63.
Bakker MF Verstappen SM Welsing PM Jacobs JW Jahangier ZN van der Veen MJ Bijlsma JW Lafeber FP;Utrecht Arthritis Cohort study group 《Arthritis research & therapy》2011,13(3):R70
Introduction
The aim of this study was to investigate whether serum biomarker levels of C2C, C1,2C, CS846, and CPII can predict the long-term course of disease activity and radiographic progression early in the disease course of rheumatoid arthritis (RA). 相似文献64.
We have broadly defined the DNA regions regulating esterase6 activity in
several life stages and tissue types of D. melanogaster using P-
element-mediated transformation of constructs that contain the esterase6
coding region and deletions or substitutions in 5' or 3' flanking DNA.
Hemolymph is a conserved ancestral site of EST6 activity in Drosophila and
the primary sequences regulating its activity lie between -171 and -25 bp
relative to the translation initiation site: deletion of these sequences
decrease activity approximately 20-fold. Hemolymph activity is also
modulated by four other DNA regions, three of which lie 5' and one of which
lies 3' of the coding region. Of these, two have positive and two have
negative effects, each of approximately twofold. Esterase6 activity is
present also in two male reproductive tract tissues; the ejaculatory bulb,
which is another ancestral activity site, and the ejaculatory duct, which
is a recently acquired site within the melanogaster species subgroup.
Activities in these tissues are at least in part independently regulated:
activity in the ejaculatory bulb is conferred by sequences between -273 and
-172 bp (threefold decrease when deleted), while activity in the
ejaculatory duct is conferred by more distal sequences between -844 and
-614 bp (fourfold decrease when deleted). The reproductive tract activity
is further modulated by two additional DNA regions, one in 5' DNA (-613 to
-284 bp; threefold decrease when deleted) and the other in 3' DNA (+1860 to
+2731 bp; threefold decrease when deleted) that probably overlaps the
adjacent esteraseP gene. Collating these data with previous studies
suggests that expression of EST6 in the ancestral sites is mainly regulated
by conserved proximal sequences while more variable distal sequences
regulate expression in the acquired ejaculatory duct site.
相似文献
65.
Robin D. Couch Allyson Dailey Fatima Zaidi Karl Navarro Christopher B. Forsyth Ece Mutlu Phillip A. Engen Ali Keshavarzian 《PloS one》2015,10(3)
Studies have shown that excessive alcohol consumption impacts the intestinal microbiota composition, causing disruption of homeostasis (dysbiosis). However, this observed change is not indicative of the dysbiotic intestinal microbiota function that could result in the production of injurious and toxic products. Thus, knowledge of the effects of alcohol on the intestinal microbiota function and their metabolites is warranted, in order to better understand the role of the intestinal microbiota in alcohol associated organ failure. Here, we report the results of a differential metabolomic analysis comparing volatile organic compounds (VOC) detected in the stool of alcoholics and non-alcoholic healthy controls. We performed the analysis with fecal samples collected after passage as well as with samples collected directly from the sigmoid lumen. Regardless of the approach to fecal collection, we found a stool VOC metabolomic signature in alcoholics that is different from healthy controls. The most notable metabolite alterations in the alcoholic samples include: (1) an elevation in the oxidative stress biomarker tetradecane; (2) a decrease in five fatty alcohols with anti-oxidant property; (3) a decrease in the short chain fatty acids propionate and isobutyrate, important in maintaining intestinal epithelial cell health and barrier integrity; (4) a decrease in alcohol consumption natural suppressant caryophyllene; (5) a decrease in natural product and hepatic steatosis attenuator camphene; and (6) decreased dimethyl disulfide and dimethyl trisulfide, microbial products of decomposition. Our results showed that intestinal microbiota function is altered in alcoholics which might promote alcohol associated pathologies. 相似文献
66.
67.
Uterine involution and postpartum ovarian activity were studied in 53 Nili-Ravi buffaloes. Mean intervals to uterine involution (26 days), regression of the corpus albicans of pregnancy (22 days), resumption of follicular activity (21 days) and first postpartum estrus (56 days) were not affected by the month of calving or age. Mean interval to formation of first corpus luteum (CL) after calving as indicated by progesterone in plasma (>/= 1.5 ng/ml) was 23.8 +/- 1.7 days, but only 52% of these CL were palpable. The number of CL formed before first postpartum estrus ranged from zero to five per buffalo; mean values based upon progesterone and palpation were 1.6 +/- 1.3 and 0.8 +/- 0.2, respectively. Based upon either progesterone or palpation, length of first postpartum luteal phase (7.9 or 6.6 days) was shorter than the luteal phase immediately preceeding the first estrus (12.1 or 8.9 days). Intervals from regular cyclic ovarian activity was not established until first estrus and intervals from the end of one luteal phase to the onset of the next were as long as three weeks. High concentrations of progesterone (>/= 1.5 ng/ml) on the day of behavioral estrus were seen in 23% of the buffaloes studied. 相似文献
68.
M O Dailey J Schreurs H Schulman 《Journal of immunology (Baltimore, Md. : 1950)》1988,140(9):2931-2936
Lymphocytes have surface receptors for a variety of hormones that play an important part in modulating the immune response. Most previous studies, however, have examined the effects of hormone agonists on heterogeneous bulk populations of cells, making it difficult to precisely identify the responding target cells. We have therefore studied a set of well characterized T cell clones for a series of adenylate cyclase-linked hormone receptors and examined changes in receptor expression that occur after cell activation. All clones tested had receptors for histamine, isoproterenol, and PGE1, but not for several other cAMP-active hormone agonists. The apparent receptor affinities and their specificities were characteristic of typical histamine H2, beta 2-adrenergic, and PGE receptors. The cAMP response to PG was higher and longer lasting than that to histamine or isoproterenol, both of which appear to undergo receptor desensitization. After activation of quiescent cells in IL-2-containing media, the cAMP response to all three ligands increased, peaking 4 to 5 days after stimulation, and then returned to basal levels as the cells ceased proliferating. Inasmuch as this effect did not require Ag, it appears that the coordinate regulation of responsiveness to these ligands is a direct result of lymphocyte activation. This increase in hormone receptor activity is functionally analogous to the up-regulation of receptors for other ligands that occurs after lymphocyte activation and further demonstrates the important immunoregulatory role played by the changing repertoire of surface receptors that is associated with activation. 相似文献
69.
P. C. Jobe S. M. Lasley R. L. Burger A. F. Bettendorf P. K. Mishra J. W. Dailey 《Amino acids》1992,3(2):155-172
Summary Seizure facilitation has been proposed as a possible adverse effect of dietary consumption of aspartame. The conversion of this sweetener to phenylalanine and aspartate in the gastrointestinal tract, and subsequent absorption, elevates plasma levels of these two amino acids. Absorbed phenylalanine competes with other large neutral amino acids, including tyrosine and tryptophan, for transport into brain. Theoretically, this competition might reduce brain tyrosine and tryptophan which could decrease synthesis of norepinephrine, dopamine and serotonin. Diminished synaptic release of these monoaminergic neurotransmitters facilitates seizures in many seizure models. Our present study evaluates effects of oral aspartame on amino acids and electroshock seizures in normal and seizure predisposed rats. Heroic doses of aspartame produced preditable changes in plasma amino acids. However, none of the aspartame doses altered seizure indices. We conclude that aspartame does not alter maximal electroshock seizures in normal rats or in rats predisposed to seizures.Preliminary data were presented at the annual meeting of the Federation of American Societies for Experimental Biology (Jobe et al., 1988).This work was supported, in part, by a grant from the NutraSweet Company. 相似文献
70.
Current phylogenetic tree reconstruction methods assume that there is a
single underlying tree topology for all sites along the sequence. The
presence of mosaic sequences due to recombination violates this assumption
and will cause phylogenetic methods to give misleading results due to the
imposition of a single tree topology on all sites. The detection of mosaic
sequences caused by recombination is therefore an important first step in
phylogenetic analysis. A graphical method for the detection of
recombination, based on the least squares method of phylogenetic
estimation, is presented here. This method locates putative recombination
breakpoints by moving a window along the sequence. The performance of the
method is assessed by simulation and by its application to a real data set.
相似文献