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1.
Pregnancy was prolonged as long as 23 days in gilts receiving daily oral 6-methyl-17 acetoxy-progesterone (MAP) at a level of 0.27–0.41 mg/kg body weight. These levels of progestin did not effect fetal welfare if administered throughout gestation and did not interfere with normal parturition and live litter size if treatment was terminated at the calculated term date which corresponded with the day of milk let-down. The initiation of milk let-down was not effected by treatment. Severe fetal death occurred in all gilts delivering young naturally during prolonged pregnancy and in gilts whose litters were delivered surgically 12 days or more after milk let-down. Mean live litter size was normal in gilts whose young were delivered surgically within 11 days of milk let-down. Fetal death at 12 days or more of prolonged pregnancy was attributed to placental insufficiency. The reproductive parameters studied were unaffected by the addition of 0.001 to 0.013 mg/kg body weight of diethylstilbestrol (DES) to the progestin treatment or the use of this agent alone.  相似文献   
2.
The epidemiology of vector transmitted plant diseases is highly influenced by dispersal and the host‐plant range of the vector. Widening the vector's host range may increase transmission potential, whereas specialization may induce specific disease cycles. The process leading to a vector's host shift and its epidemiological outcome is therefore embedded in the frameworks of sympatric evolution vs. immigration of preadapted populations. In this study, we analyse whether a host shift of the stolbur phytoplasma vector, Hyalesthes obsoletus from field bindweed to stinging nettle in its northern distribution range evolved sympatrically or by immigration. The exploitation of stinging nettle has led to outbreaks of the grapevine disease bois noir caused by a stinging nettle‐specific phytoplasma strain. Microsatellite data from populations from northern and ancestral ranges provide strong evidence for sympatric host‐race evolution in the northern range: Host‐plant associated populations were significantly differentiated among syntopic sites (0.054 < FHT < 0.098) and constant over 5 years. While gene flow was asymmetric from the old into the predicted new host race, which had significantly reduced genetic diversity, the genetic identity between syntopic host‐race populations in the northern range was higher than between these populations and syntopic populations in ancestral ranges, where there was no evidence for genetic host races. Although immigration was detected in the northern field bindweed population, it cannot explain host‐race diversification but suggests the introduction of a stinging nettle‐specific phytoplasma strain by plant‐unspecific vectors. The evolution of host races in the northern range has led to specific vector‐based bois noir disease cycles.  相似文献   
3.

Background

The pro-inflammatory status of the elderly triggers most of the age-related diseases such as cancer and atherosclerosis. Atherosclerosis, the leading cause world wide of morbidity and death, is an inflammatory disease influenced by life-style and genetic host factors. Stimuli such as oxLDL or microbial ligands have been proposed to trigger inflammation leading to atherosclerosis. It has recently been shown that oxLDL activates immune cells via the Toll-like receptor (TLR) 4/6 complex. Several common single nucleotide polymorphisms (SNPs) of the TLR system have been associated with atherosclerosis. To investigate the role of TLR-6 we analyzed the association of the TLR-6 SNP Pro249Ser with atherogenesis.

Results

Genotyping of two independent groups with CAD, as well as of healthy controls revealed a significant association of the homozygous genotype with a reduced risk for atherosclerosis (odds ratio: 0.69, 95% CI 0.51-0.95, P?=?0.02). In addition, we found a trend towards an association with the risk of restenosis after transluminal coronary angioplasty (odds ratio: 0.53, 95% CI 0.24-1.16, P?=?0.12). In addition, first evidence is presented that the frequency of this protective genotype increases in a healthy population with age. Taken together, our results define a role for TLR-6 and its genetic variations in modulating the inflammatory response leading to atherosclerosis.

Conclusions

These results may lead to a better risk stratification, and potentially to an improved prophylactic treatment of high-risk populations. Furthermore, the protective effect of this polymorphism may lead to an increase of this genotype in the healthy elderly and may therefore be a novel genetic marker for the well-being during aging.
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4.
Recent studies suggest that the therapeutic effects of stem cell transplantation following myocardial infarction (MI) are mediated by paracrine factors. One of the main goals in the treatment of ischemic heart disease is to stimulate vascular repair mechanisms. Here, we sought to explore the therapeutic angiogenic potential of mesenchymal stem cell (MSC) secretions. Human MSC secretions were collected as conditioned medium (MSC-CM) using a clinically compliant protocol. Based on proteomic and pathway analysis of MSC-CM, an in vitro assay of HUVEC spheroids was performed identifying the angiogenic properties of MSC-CM. Subsequently, pigs were subjected to surgical left circumflex coronary artery ligation and randomized to intravenous MSC-CM treatment or non-CM (NCM) treatment for 7 days. Three weeks after MI, myocardial capillary density was higher in pigs treated with MSC-CM (645 ± 114 vs 981 ± 55 capillaries/mm(2); P = 0.021), which was accompanied by reduced myocardial infarct size and preserved systolic and diastolic performance. Intravenous MSC-CM treatment after myocardial infarction increases capillary density and preserves cardiac function, probably by increasing myocardial perfusion.  相似文献   
5.
Plant and Soil - We imaged the sub-mm distribution of labile P and pH in the rhizosphere of three plant species to localize zones and hot spots of P depletion and accumulation along individual root...  相似文献   
6.
Mutations in the human ABCA3 gene, encoding an ABC-transporter, are associated with respiratory failure in newborns and pediatric interstitial lung disease. In order to study disease mechanisms, a transgenic mouse model with a disrupted Abca3 gene was generated by targeting embryonic stem cells. While heterozygous animals developed normally and were fertile, individuals homozygous for the altered allele (Abca3-/-) died within one hour after birth from respiratory failure, ABCA3 protein being undetectable. Abca3-/- newborns showed atelectasis of the lung in comparison to a normal gas content in unaffected or heterozygous littermates. Electron microscopy demonstrated the absence of normal lamellar bodies in type II pneumocytes. Instead, condensed structures with apparent absence of lipid content were found. We conclude that ABCA3 is required for the formation of lamellar bodies and lung surfactant function. The phenotype of respiratory failure immediately after birth corresponds to the clinical course of severe ABCA3 mutations in human newborns.  相似文献   
7.
According to the common view, weak acid uncouplers increase proton conductance of biological (and phospholipid bilayer) membranes, thus effecting H+ fluxes driven by their electrochemical gradients. Under certain conditions, however, uncouplers can induce unexpected effects opposite to the dissipation of H+ gradients. Results are presented here demonstrating CCCP-induced proton influx into Saccharomyces cerevisiae cytosol driven by the electrochemical potentials of CCCP and its CCCP? anions, independent of electrochemical H+-gradient. Another view of week acid uncouplers’ action is proposed that is logically consistent with these observations.  相似文献   
8.

Background

We need new biomarkers that can predict cardiovascular disease to improve both diagnosis and therapeutic strategies. The CIRCULATING CELLS study was designed to study the role of several cellular mediators of atherosclerosis as biomarkers of coronary artery disease (CAD). An objective and reproducible method for the quantification of CAD extension is required to establish relationships with these potential biomarkers. We sought to analyse the correlation of the SYNTAX score with known CAD risk factors to test it as a valid marker of CAD extension.

Methods and results

A subgroup of 279 patients (67.4% males) were included in our analysis. Main exclusion criteria were a history of previous percutaneous coronary intervention or surgical revascularisation that prevent an accurate assessment of the SS. Diabetes mellitus, smoking, renal insufficiency, body mass index and a history of CAD and myocardial infarction were all positively and strongly associated with a higher SYNTAX score after adjustment for the non-modifiable biological factors (age and sex). In the multivariate model, age and male sex, along with smoking and renal insufficiency, remain statistical significantly associated with the SYNTAX score.

Conclusion

In a selected cohort of revascularisation-naive patients with CAD undergoing coronary angiography, non-modifiable cardiovascular risk factors such as advanced age, male sex, as well as smoking and renal failure were independently associated with CAD complexity assessed by the SYNTAX score. The SYNTAX score may be a valid marker of CAD extension to establish relationships with potential novel biomarkers of coronary atherosclerosis.
  相似文献   
9.
The quagga mussel Dreissena rostriformis bugensis, native to the Dnieper and the northern Black Sea, has become a major invasive species in both the Volga River and the North American Great Lakes since the early 1990s. Findings in the Netherlands (2006) and Germany (2007) mark the start of its establishment in Western Europe. We investigated the current distribution, time of first arrival and population structure of D. rostriformis bugensis from the rivers Rhine, Main and in the Main-Danube canal in Germany. Two putative sources of the German populations were analysed by genetically comparing these populations to older invasive populations from North America and the southeast Danube. Dreissena rostriformis bugensis was abundant in the Main and in three Rhine harbours, but rare in the actual Rhine river and absent south of the Main-Danube canal. Mussels found in the Rhine harbours were significantly smaller than in the Main. Population genetic analyses found no sign of founder effects and minimal differentiation between German, North American and southeast Danube populations. The genetic data suggest that these invasive populations derive from a common and rapidly expanding source. Based on the non-continuous distribution and shell size differences of Rhine harbour and Main populations, our results indicate that expansion in Germany involved at least two independent settling events, one of which happened before 2005, and most likely was caused by jump dispersal.  相似文献   
10.
To simplify and facilitate beating heart (i.e., off-pump), minimally invasive coronary artery bypass surgery, a new coronary anastomotic connector, the Trinity Clip, is developed based on the excimer laser-assisted nonocclusive anastomosis technique. The Trinity Clip connector enables simplified, sutureless, and nonocclusive connection of the graft to the coronary artery, and an excimer laser catheter laser-punches the opening of the anastomosis. Consequently, owing to the complete nonocclusive anastomosis construction, coronary conditioning (i.e., occluding or shunting) is not necessary, in contrast to the conventional anastomotic technique, hence simplifying the off-pump bypass procedure. Prior to clinical application in coronary artery bypass grafting, the safety and quality of this novel connector will be evaluated in a long-term experimental porcine off-pump coronary artery bypass (OPCAB) study. In this paper, we describe how to evaluate the coronary anastomosis in the porcine OPCAB model using various techniques to assess its quality. Representative results are summarized and visually demonstrated.  相似文献   
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