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The age-associated changes in dopamine subtype receptors were examined in Aplysia californica. The density of the subtype receptors D1, D2, D3 and D4 was examined in the ganglia from 4.5-, 6-, 8-, 9- and 12-month animals. Receptor analysis was performed by examining the binding of radiolabeled ligands to the individual subtypes. [3H]SCH23390 and [3H]Clozapine were used to analyze D1 and D4 specific binding. [3H]Quinpirole was used for determining D2 and D3 specific binding. Specific binding was found to be present for all four receptor subtypes. All receptor subtypes showed an increase in density from 4.5 to 6 months. From 6 to 8 months D2 and D3 decreased, while D1 and D4 increased. D4 showed the strongest increase. All four subtypes examined showed decreases from 8 to 12 months. ANOVA results indicated age was a significant factor in the subtype receptor density for all receptor types.  相似文献   
123.
The effect of six phosphorus levels (0, 40, 80, 120, 160 and 200 kg/ha) on the duration of cumulative leaf area, biomass and agronomic yield was determined in the maize cultivars: Amarillo Almoloya, Cacahuacintle and Condor in 2010 and 2011. Such cultivars were sown in the Cerrillo Piedras Blancas Mexico. A completely randomized complete block design with factorial arrangement was utilized. High phosphorus levels (120, 160 and 200 kg/ha) positively affected the duration of cumulative leaf area; greatest values were obtained in Cacahuacintle. A greater duration of accumulated leaf area contributes to determine high values of biomass accumulation and grain yield in this cultivar. Leaf area duration appeared to be a useful tool for evaluating different genotypes in a given environment.  相似文献   
124.
When L929 cells are exposed to 5 μg/ml dexamethasone, synthesis of a 90,000 M(r) polypeptide is induced within 12 h. Flattening of the cells begins at about this time and progresses to become quite prominent after 48 h of exposure. Two-dimensional PAGE and partial proteolytic fingerprints identify the 90,000 M(r) polypeptide as gelsolin, a Ca(++)-dependent inhibitor of actin polymerization. Thus, this system provides evidence that gelsolin may have a role in regulating cell shape in response to physiological agents such as glucocorticoids.  相似文献   
125.
Hilary A. Southall 《CMAJ》1985,133(10):1029-1039
A sample survey of Canadian Medical Association (CMA) members, conducted in early summer 1985 and designed to provide information to help guide the association''s activities and policies, shows that most Canadian physicians support involvement in political activities both by CMA and by indivudual physicians. A majority wishes to maintain the concept of extra/balance billing, to pursue the position that the health care system is underfunded and favours medicare premiums and hospital user fees as the preferred methods for increasing revenue.Most respondents believe that the number of doctors in Canada is about right but would prefer any reduction to be achieved by cutting medical school admissions or reducing postgraduate training positions open to graduates of foreign medical schools.Most of those members who know of CMA policies on a number of health care issues agree with them and also find them useful, but a significant proportion are not aware of their content.There is support for compulsory payment of dues by all licensed physicians to both their provincial medical association and CMA. A majority would like more information on pharmaceutical products and additional membership surveys.  相似文献   
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CD24 is a glycophosphatidylinositol (GPI)-linked cell surface receptor that is involved in regulating the survival or differentiation of several different cell types. CD24 has been used to identify pre-adipocytes that are able to reconstitute white adipose tissue (WAT) in vivo. Moreover, we recently found that the dynamic upregulation of CD24 in vitro during early phases of adipogenesis is necessary for mature adipocyte development. To determine the role of CD24 in adipocyte development in vivo, we evaluated the development of the inguinal and interscapular subcutaneous WAT and the epididymal visceral WAT in mice with a homozygous deletion of CD24 (CD24KO). We observed a significant decrease in WAT mass of 40% to 74% in WAT mass from both visceral and subcutaneous depots in male mice, with no significant effect in female mice, compared to wild-type (WT) sex- and age-matched controls. We also found that CD24KO mice had increased fasting glucose and free fatty acids, decreased fasting insulin, and plasma leptin. No major differences were observed in the sensitivity to insulin or glucose, or in circulating triglycerides, total cholesterol, HDL-cholesterol, or LDL-cholesterol levels between WT and CD24KO mice. Challenging the CD24KO mice with either high sucrose (35%) or high fat (45%) diets that promote increased adiposity, increased WAT mass and fasting insulin, adiponectin and leptin levels, as well as reduced the sensitivity to insulin and glucose, to the levels of WT mice on the same diets. The CD24-mediated reduction in fat pad size was due to a reduction in adipocyte cell size in all depots with no significant reduction pre-adipocyte or adipocyte cell number. Thus, we have clearly demonstrated that the global absence of CD24 affects adipocyte cell size in vivo in a sex- and diet-dependent manner, as well as causing metabolic disturbances in glucose homeostasis and free fatty acid levels.  相似文献   
128.

Background

For a good probiotic candidate, the abilities to adhere to intestinal epithelium and to fortify barrier function are considered to be crucial for colonization and functionality of the strain. The strain Lactobacillus acidophilus LAB20 was isolated from the jejunum of a healthy dog, where it was found to be the most pre-dominant lactobacilli. In this study, the adhesion ability of LAB20 to intestinal epithelial cell (IECs) lines, IECs isolated from canine intestinal biopsies, and to canine, porcine and human intestinal mucus was investigated. Further, we studied the ability of LAB20 to fortify the epithelial cell monolayer and to reduce LPS-induced interleukin (IL-8) release from enterocytes.

Results

We found that LAB20 presented higher adhesion to canine colonic mucus as compared to mucus isolated from porcine colon. LAB20 showed adhesion to HT-29 and Caco-2 cell lines, and importantly also to canine IECs isolated from canine intestinal biopsies. In addition, LAB20 increased the transepithelial electrical resistance (TER) of enterocyte monolayers and thus strengthened the intestinal barrier function. The strain showed also anti-inflammatory capacity in being able to attenuate the LPS-induced IL-8 production of HT-29 cells.

Conclusion

In conclusion, canine indigenous strain LAB20 is a potential probiotic candidate for dogs adhering to the host epithelium and showing intestinal barrier fortifying and anti-inflammatory effects.

Electronic supplementary material

The online version of this article (doi:10.1186/s12866-014-0337-9) contains supplementary material, which is available to authorized users.  相似文献   
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130.

Background

We consider the potential for infection to spread in a farm population from the primary outbreak farm via livestock movements prior to disease detection. We analyse how this depends on the time of the year infection occurs, the species transmitting, the length of infectious period on the primary outbreak farm, location of the primary outbreak, and whether a livestock market becomes involved. We consider short infectious periods of 1 week, 2 weeks and 4 weeks, characteristic of acute contagious livestock diseases. The analysis is based on farms in Scotland from 1 January 2003 to 31 July 2007.

Results

The proportion of primary outbreaks from which an acute contagious disease would spread via movement of livestock is generally low, but exhibits distinct annual cyclicity with peaks in May and August. The distance that livestock are moved varies similarly: at the time of the year when the potential for spread via movements is highest, the geographical spread via movements is largest. The seasonal patterns for cattle differ from those for sheep whilst there is no obvious seasonality for pigs. When spread via movements does occur, there is a high risk of infection reaching a livestock market; infection of markets can amplify disease spread. The proportion of primary outbreaks that would spread infection via livestock movements varies significantly between geographical regions.

Conclusions

In this paper we introduce a set-up for analysis of movement data that allows for a generalized assessment of the risk associated with infection spreading from a primary outbreak farm via livestock movements, applying this to Scotland, we assess how this risk depends upon the time of the year, species transmitting, location of the farm and other factors.  相似文献   
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