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41.
MyD88 is a key downstream adapter for most Toll-like receptors (TLRs) and interleukin-1 receptors (IL-1Rs). MyD88 deficiency in mice leads to susceptibility to a broad range of pathogens in experimental settings of infection. We describe a distinct situation in a natural setting of human infection. Nine children with autosomal recessive MyD88 deficiency suffered from life-threatening, often recurrent pyogenic bacterial infections, including invasive pneumococcal disease. However, these patients were otherwise healthy, with normal resistance to other microbes. Their clinical status improved with age, but not due to any cellular leakiness in MyD88 deficiency. The MyD88-dependent TLRs and IL-1Rs are therefore essential for protective immunity to a small number of pyogenic bacteria, but redundant for host defense to most natural infections.  相似文献   
42.
Fruit thinning in pear is feasible for mitigation of water stress effects. However, it is not well known how fruit quality at harvest and after cold storage is affected by pre-harvest water stress. Even less is known about the effects of fruit thinning on quality under these circumstances. To elucidate these, we applied deficit irrigation (DI) and fruit thinning treatments to ‘Conference’ pear over the growing seasons of 2008 and 2009. At the onset of Stage II (80 and 67 days before harvest in 2008 and 2009, respectively), two irrigation treatments were applied: full irrigation (FI) and DI. FI trees received 100% of crop evapotranspiration (ETc). DI trees received no irrigation during the first three weeks of Stage II to induce water stress, but then received 20% of ETc to ensure tree survival. From bud-break until the onset of Stage II and during post-harvest, FI and DI trees received 100% of ETc. Each irrigation treatment received two thinning levels: no thinning leaving commercial crop load (∼180 fruits tree−1), and hand-thinning at the onset of Stage II leaving a light crop load (∼85 fruits tree−1). Under commercial crop loads, DI trees were moderately water-stressed and this had some positive effects on fruit quality. DI increased fruit firmness (FF), soluble solids concentrations (SSC) and acidity at harvest while no changes were observed in fruit maturity (based on ethylene production). Differences in FF and acidity at harvest between FI and DI fruit were maintained during cold storage. DI also reduced fruit weight loss during storage. But fruit size was reduced under DI. Fruit thinning under DI resulted in better fruit composition with no detrimental effect on fresh-market yield compared to un-thinned fruit. Fruit size at harvest and SSC values after five months of cold storage were higher in fruit from thinned trees than fruit from un-thinned trees. Fruit thinning increased fruit ethylene production, indicating advanced maturity. This may lead to earlier harvest which is desirable in years with impending drought. Fruit thinning is therefore a useful technique to enhance pear marketability under water shortage.  相似文献   
43.
Landscape Ecology - Protected areas (PAs) are essential for biodiversity conservation and the provision of ecosystem services (ES), representing 15% of the earth’s surface and targeted to...  相似文献   
44.
One hundred and seven fattening pig units randomly selected in Catalonia (Spain) were surveyed during 2001-2003, in order to determine the frequency of the prophylactic use of antimicrobials and mass treatments against respiratory and enteric disease outbreaks. Logistic regression and regression tree analysis were done to determine the factors associated with the on-farm mass antimicrobial usage. Fifty-eight per cent of the surveyed farms used mass antimicrobial prophylaxis; among them, 39% used two or more antimicrobials. The more frequently administered drugs were colistin, beta-lactams and tetracyclines. Fattening units from strict finishing farms were more likely to use antimicrobials than farrow-to-finish farms (Odds Ratio = 11.7) and farms with changing facilities were less likely to use these compounds (OR = 0.17). In the event of a respiratory disease outbreak, most farms applied mass treatment and 46% used two or more compounds, with tetracyclines, beta-lactams and sulphonamides being the most popular ones. Mass treatment with several compounds in case of respiratory problems was significantly related to the use of growth promoters on the farm (OR = 4.3). If an outbreak of an enteric disease occurred, most farms resorted also to a mass treatment and 48% used two or more drugs. The most frequent antimicrobial agent for the treatment of enteric disease was colistin. Fattening farms (OR = 6.9) and operations that perform routine antimicrobial prophylaxis (OR = 2.0) were more likely to use more than one antimicrobial agent for enteric diseases.  相似文献   
45.
Background:Genetic selection in cattle has been directed to increase milk production.This,coupled to the fact that the vast majority of bovine artificial inseminations(AI)are performed using cryopreserved sperm,have led to a reduction of fertility rates over the years.Thus,seeking sensitive and specific sperm biomarkers able to predict fertility rates is of vital importance to improve cattle reproductive efficiency.In humans,sperm chromatin condensation evaluated through chromomycin A3(CMA3)has recently been purported to be a powerful biomarker for sperm functional status and male infertility.The objectives of the present study were:a)to set up a flow cytometry method for simultaneously evaluating chromatin condensation and sperm viability,and b)to test whether this parameter could be used as a predictor of in vivo fertility in bulls.The study included pools of three independent cryopreserved ejaculates per bull from 25 Holstein males.Reproductive outcomes of each sire were determined by non-return rates,which were used to classify bulls into two groups(highly fertile and subfertile).Results:Chromatin condensation status of bovine sperm was evaluated through the combination of CMA3 and Yo-Pro-1 staining and flow cytometry.Sperm quality parameters(morphology,viability,total and progressive motility)were also assessed.Pearson correlation coefficients and ROC curves were calculated to assess their capacity to predict in vivo fertility.Sperm morphology,viability and total motility presented an area under the ROC curve(AUC)of 0.54,0.64 and 0.68,respectively(P>0.05),and thus were not able to discriminate between fertile and subfertile individuals.Alternatively,while the percentage of progressively motile sperm showed a significant predictive value,with an AUC of 0.73(P=0.05),CMA3/Yo-Pro-1 staining even depicted superior results for the prediction of in vivo fertility in bulls.Specifically,the percentage of viable sperm with poor chromatin condensation showed better accuracy and precision to predict in vivo fertility,with an AUC of 0.78(P=0.02).Conclusions:Chromatin condensation evaluated through CMA3/Yo-Pro-1 and flow cytometry is defined here as a more powerful tool than conventional sperm parameters to predict bull in vivo fertility,with a potential ability to maximising the efficiency of dairy breeding industry.  相似文献   
46.
OBJECTIVE: To compare the efficacy of meloxicam administered perioperatively with transdermal administration of fentanyl via a patch placed preoperatively in dogs undergoing orthopedic surgery. DESIGN: Prospective study. ANIMALS: 16 dogs. PROCEDURE: Unilateral or bilateral osteotomy of the tibia and fibula was surgically performed, and a uniplanar external distraction device was placed in each limb. Postoperative pain and lameness were assessed 24, 48, and 72 hours after administration of the first of 3 doses of meloxicam (0.2 mg/kg [0.09 mg/lb], IV, given preoperatively, followed by 0.1 mg/kg [0.045 mg/lb], IV, after 24 hours, and 0.1 mg/kg, PO, after 48 hours) or preoperative placement of a transdermal fentanyl patch (50 microg/h) left in place for 72 hours. RESULTS: No significant differences in total pain scores were detected between groups. Mean +/- SD lameness scores assessed at 24 and 72 hours were lower in dogs in the meloxicam group than dogs in the fentanyl group. Lameness scores decreased with time in a similar manner in both treatment groups. CONCLUSIONS AND CLINICAL RELEVANCE: Perioperative administration of meloxicam or preoperative placement of a transdermal fentanyl patch provided effective and similar postoperative analgesia in dogs undergoing orthopedic surgery. However, because of its anti-inflammatory effects, treatment with meloxicam reduced the degree of lameness and resulted in rapid functional recovery of the limb.  相似文献   
47.
48.
Tropical Animal Health and Production - Bovine brucellosis is a zoonotic disease that causes great economic losses. The disease is endemic in Colombia and animal movements from infected herds carry...  相似文献   
49.
Vegetative propagation techniques such as grafting can be used, in conjunction with field studies, to decouple the relative effects of age and size on tree metabolism and growth. Despite interest in this approach, little attention has been paid to the best metrics for assessing the growth performance of grafted plants over time. Based on an analysis of the grafting literature and our own data, we show that the choice of metrics to assess tree growth can entirely change the conclusions reached about the relative importance of age versus size. We recommend that absolute as well as relative rates of growth are calculated and that scion size be standardized as much as possible at the start of the experiment. Once proper metrics are chosen, all of the available published evidence is largely concordant with two concepts: (1) age-mediated controls of tree growth are likely to be important during the first few years of a tree's life (before phase change); and (2) after the first few years of a tree's life, size-mediated factors largely prevail over age-mediated factors in determining tree growth rates. We found no support for theories invoking age-mediated sink limitations in old trees.  相似文献   
50.
Growth and production in the first year, as additional selection criteria, were assessed for nine poplar clones to be used as short rotation woody crops (SRWC) in the production of biomass for energy purposes. In order to identify the most promising clones in terms of growth and yield and also to assess their stability, trials were established at different locations in Spain. The majority of these clones, which form part of the European list of base materials, have frequently been used in plantations aimed at timber production but not for biomass in Mediterranean conditions. Others, such as those selected in Italy specifically for biomass production (currently provisionally admitted), are being tested for the first time under different soil and climatic conditions in Southwest Europe. The early selection of clones for rapid juvenile growth provides a valuable additional input to the clonal selection process, especially where very short rotations are desired (no more than 3 years). In any case, determining clonal stability in terms of growth is of great use not only when deciding on the clones to be used in plantations but also when developing breeding programs. ANOVA and Genotype plus Genotype × Environment (GGE) biplot analyses were used to analyse the growth and stability of the clones, which were then ranked according to mean performance and stability. Differences were detected between clones as well as between the different environments tested. The biplot analysis allowed different groups of clones to be identified according to their performance and degree of interaction displayed, thus providing useful information for the selection process. The production of aboveground biomass in the first vegetative period ranged from 1.7 to 8.0 Mg DM ha−1 at the different sites. ‘Monviso’, ‘Guardi’, ‘AF2’ and ‘2000 verde’ were the most productive clones whereas ‘Unal’, ‘Pegaso’ and ‘USA 49-177’ were the least productive. The stability analysis identified ‘AF2’, ‘Guardi’, ‘I-214’ and ‘MC’ as more stable clones while ‘Monviso’, ‘2000 verde’, ‘Unal’, ‘Pegaso’ and ‘USA 49-177’ were found to be specifically adapted to certain environments. This implies that where information on site conditions is not available, the ‘AF2’ and ‘Guardi’ clones offer greater assurance of successful establishment and higher initial growth. The growth of ‘Monviso’ ‘2000 verde’ ‘Unal’ ‘Pegaso’ and ‘USA 49-177’ clones is highly dependent on site conditions during the establishment phase. Similarly, the SH (Shore Henares river) and LT (La Tallada) sites were identified as the most highly discriminative environments for the set of clones while CS (Cubo de la Solana) and AR (Atarfe) were identified as those where performance levels were average.  相似文献   
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