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排序方式: 共有368条查询结果,搜索用时 31 毫秒
1.
A method was developed to optimize simultaneous selection for a quantitative trait with a known QTL within a male and a female line to maximize crossbred performance from a two-way cross. Strategies to maximize cumulative discounted response in crossbred performance over ten generations were derived by optimizing weights in an index of a QTL and phenotype. Strategies were compared to selection on purebred phenotype. Extra responses were limited for QTL with additive and partial dominance effects, but substantial for QTL with over-dominance, for which optimal QTL selection resulted in differential selection in male and female lines to increase the frequency of heterozygotes and polygenic responses. For over-dominant QTL, maximization of crossbred performance one generation at a time resulted in similar responses as optimization across all generations and simultaneous optimal selection in a male and female line resulted in greater response than optimal selection within a single line without crossbreeding. Results show that strategic use of information on over-dominant QTL can enhance crossbred performance without crossbred testing. 相似文献
2.
R A Rathod L J Bhagia G L Pandya V L Katagade D J Parikh B B Chatterjee 《European journal of applied physiology and occupational physiology》1987,56(1):58-63
A preliminary survey of the few units of the small-scale glass bangle industry in Firozabad, Agra District, Uttar Pradesh, indicated that the workers were exposed to severe degrees of heat stress during various operations in the manufacturing processes. A more detailed study in eight glass bangle units was therefore undertaken to make quantitative estimates of heat stress on exposed workers in the summer season. The thermal data collected confirmed that the heat stress on the workers was severe but measurement of certain physiological indicators revealed relatively low levels of strain amongst the exposed workers. The findings could be attributable to high degrees of acclimatization, but further observations in the field supplemented by studies on simulated exposures of volunteers in a climatic chamber seem to be warranted. 相似文献
3.
Previously, we reported that incorporation of threo-beta-fluoroasparagine into cellular protein inhibits N-linked glycosylation. We now show that short synthetic peptides which contain N-acetyl-threo-beta-fluoroasparagine fail to undergo glycosylation in a cell-free system except at extremely high substrate concentrations. An N-benzoyl-threo-beta-fluoroasparagine-containing peptide has a 100-fold lower Vmax/Km than the analogous N-benzoyl-asparagine-containing peptide. Substitution of a fluorine for a hydrogen on the beta-carbon of asparagine weakens the ability of the peptide to bind the oligosaccharyltransferase. A 100-fold excess of acetyl-threo-beta-fluoroasparaginyl-leucyl-threonine methylamide over acetyl-asparaginyl-leucyl-threonine methylamide inhibited glycosylation of the latter peptide by less than 10%. Both threo-beta-fluoroasparagine and erythro-beta-fluoroasparagine-containing peptides are glycosylated at the same rate. Glycofluoropeptides generated from beta-fluoroasparagine-containing peptides were N-glycosylated. These cell-free studies with synthetic fluoropeptides suggest that incorporation of beta-fluoroasparagine into cellular protein inhibits N-linked glycosylation by rendering protein substrates ineffective for glycosylation. In the course of this work, we also demonstrate that the N-linked glycosylating enzyme acts only on L-asparagine-containing peptides and not on D-asparagine peptides. 相似文献
4.
Tazeen Hasan Jafar Ngiap Chuan Tan Rupesh Madhukar Shirore John Carson Allen Eric Andrew Finkelstein Siew Wai Hwang Agnes Ying Leng Koong Peter Kirm Seng Moey Gary Chun-Yun Kang Chris Wan Teng Goh Reena Chandhini Subramanian Anandan Gerard Thiagarajah Chandrika Ramakrishnan Ching Wee Lim Jianying Liu for SingHypertension Study Group 《PLoS medicine》2022,19(6)
BackgroundDespite availability of clinical practice guidelines for hypertension management, blood pressure (BP) control remains sub-optimal (<30%) even in high-income countries. This study aims to assess the effectiveness of a potentially scalable multicomponent intervention integrated into primary care system compared to usual care on BP control.Methods and findingsA cluster-randomized controlled trial was conducted in 8 government clinics in Singapore. The trial enrolled 916 patients aged ≥40 years with uncontrolled hypertension (systolic BP (SBP) ≥140 mmHg or diastolic BP (DBP) ≥90 mmHg).Multicomponent intervention consisted of physician training in risk-based treatment of hypertension, subsidized losartan-HCTZ single-pill combination (SPC) medications, nurse training in motivational conversations (MCs), and telephone follow-ups. Usual care (controls) comprised of routine care in the clinics, no MC or telephone follow-ups, and no subsidy on SPCs. The primary outcome was mean SBP at 24 months’ post-baseline. Four clinics (447 patients) were randomized to intervention and 4 (469) to usual care. Patient enrolment commenced in January 2017, and follow-up was during December 2018 to September 2020. Analysis used intention-to-treat principles. The primary outcome was SBP at 24 months. BP at baseline, 12 and 24 months was modeled at the patient level in a likelihood-based, linear mixed model repeated measures analysis with treatment group, follow-up, treatment group × follow-up interaction as fixed effects, and random cluster (clinic) effects.A total of 766 (83.6%) patients completed 2-year follow-up. A total of 63 (14.1%) and 87 (18.6%) patients in intervention and in usual care, respectively, were lost to follow-up. At 24 months, the adjusted mean SBP was significantly lower in the intervention group compared to usual care (−3.3 mmHg; 95% CI: −6.34, −0.32; p = 0.03). The intervention led to higher BP control (odds ratio 1.51; 95% CI: 1.10, 2.09; p = 0.01), lower odds of high (>20%) 10-year cardiovascular risk score (OR 0.67; 95% CI: 0.47, 0.97; p = 0.03), and lower mean log albuminuria (−0.22; 95% CI: −0.41, −0.02; p = 0.03). Mean DBP, mortality rates, and serious adverse events including hospitalizations were not different between groups. The main limitation was no masking in the trial.ConclusionsA multicomponent intervention consisting of physicians trained in risk-based treatment, subsidized SPC medications, nurse-delivered motivational conversation, and telephone follow-ups improved BP control and lowered cardiovascular risk. Wide-scale implementation of a multicomponent intervention such as the one in our trial is likely to reduce hypertension-related morbidity and mortality globally.Trial registrationTrial Registration: Clinicaltrials.gov .Tazeen H Jafar and colleagues present findings from a cluster-randomized controlled trial conducted to evaluate the effectiveness of an intervention designed to manage hypertension. NCT02972619相似文献
5.
Mahendra Rai Dnyaneshwar Rathod Gauravi Agarkar Mudasir Dar Marian Brestic Glaucia Maria Pastore Mario Roberto Marostica Junior 《Symbiosis (Philadelphia, Pa.)》2014,62(2):63-79
Agricultural productivity suffers a heavy loss due to plant pathogens, insect pests and various abiotic stresses. Agriculture being the world’s largest economic sector, it is the need of time to find and establish the ideal strategy for sustainable agriculture and improvement in crop growth. Endophytes are microorganisms that asymptomatically grow within the plant tissues without causing any disease to the host. Endophytic fungi live in symbiotic association with plants and play an important role in plant growth promotion, higher seed yield and plants resistant to various biotic, abiotic stresses and diseases. Many are able to produce antimicrobial compounds, plant growth hormones and various agrochemical bioactive metabolites. These mycoendophytes hold enormous potential for the development of eco-friendly and economically viable agricultural products. In this review we focused on the endophytic fungi recovered from different medicinal plants, their active principles involved in plant growth enhancement and the applications of fungal endophytes in agriculture. Moreover, we also discussed about endophytic fungi and their pragmatic approach towards sustainable food and agriculture. 相似文献
6.
Comprehensive epitope analysis of human immunodeficiency virus type 1 (HIV-1)-specific T-cell responses directed against the entire expressed HIV-1 genome demonstrate broadly directed responses,but no correlation to viral load 总被引:24,自引:0,他引:24
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Addo MM Yu XG Rathod A Cohen D Eldridge RL Strick D Johnston MN Corcoran C Wurcel AG Fitzpatrick CA Feeney ME Rodriguez WR Basgoz N Draenert R Stone DR Brander C Goulder PJ Rosenberg ES Altfeld M Walker BD 《Journal of virology》2003,77(3):2081-2092
Cellular immune responses play a critical role in the control of human immunodeficiency virus type 1 (HIV-1); however, the breadth of these responses at the single-epitope level has not been comprehensively assessed. We therefore screened peripheral blood mononuclear cells (PBMC) from 57 individuals at different stages of HIV-1 infection for virus-specific T-cell responses using a matrix of 504 overlapping peptides spanning all expressed HIV-1 proteins in a gamma interferon-enzyme-linked immunospot (Elispot) assay. HIV-1-specific T-cell responses were detectable in all study subjects, with a median of 14 individual epitopic regions targeted per person (range, 2 to 42), and all 14 HIV-1 protein subunits were recognized. HIV-1 p24-Gag and Nef contained the highest epitope density and were also the most frequently recognized HIV-1 proteins. The total magnitude of the HIV-1-specific response ranged from 280 to 25,860 spot-forming cells (SFC)/10(6) PBMC (median, 4,245) among all study participants. However, the number of epitopic regions targeted, the protein subunits recognized, and the total magnitude of HIV-1-specific responses varied significantly among the tested individuals, with the strongest and broadest responses detectable in individuals with untreated chronic HIV-1 infection. Neither the breadth nor the magnitude of the total HIV-1-specific CD8+-T-cell responses correlated with plasma viral load. We conclude that a peptide matrix-based Elispot assay allows for rapid, sensitive, specific, and efficient assessment of cellular immune responses directed against the entire expressed HIV-1 genome. These data also suggest that the impact of T-cell responses on control of viral replication cannot be explained by the mere quantification of the magnitude and breadth of the CD8+-T-cell response, even if a comprehensive pan-genome screening approach is applied. 相似文献
7.
C McBerry CE Egan R Rani Y Yang D Wu N Boespflug L Boon B Butcher J Mirpuri SP Hogan EY Denkers J Aliberti DR Herbert 《Journal of immunology (Baltimore, Md. : 1950)》2012,189(6):3078-3084
IL-12-mediated type 1 inflammation confers host protection against the parasitic protozoan Toxoplasma gondii. However, production of IFN-γ, another type 1 inflammatory cytokine, also drives lethality from excessive injury to the intestinal epithelium. As mechanisms that restore epithelial barrier function following infection remain poorly understood, this study investigated the role of trefoil factor 2 (TFF2), a well-established regulator of mucosal tissue repair. Paradoxically, TFF2 antagonized IL-12 release from dendritic cells (DCs) and macrophages, which protected TFF2-deficient (TFF2(-/-)) mice from T. gondii pathogenesis. Dysregulated intestinal homeostasis in naive TFF2(-/-) mice correlated with increased IL-12/23p40 levels and enhanced T cell recruitment at baseline. Infected TFF2(-/-) mice displayed low rates of parasite replication and reduced gut immunopathology, whereas wild-type (WT) mice experienced disseminated infection and lethal ileitis. p38 MAPK activation and IL-12p70 production was more robust from TFF2(-/-)CD8(+) DC compared with WT CD8(+) DC and treatment of WT DC with rTFF2 suppressed TLR-induced IL-12/23p40 production. Neutralization of IFN-γ and IL-12 in TFF2(-/-) animals abrogated resistance shown by enhanced parasite replication and infection-induced morbidity. Hence, TFF2 regulated intestinal barrier function and type 1 cytokine release from myeloid phagocytes, which dictated the outcome of oral T. gondii infection in mice. 相似文献
8.
Younis N Sharma R Soran H Charlton-Menys V Elseweidy M Durrington PN 《Current opinion in lipidology》2008,19(4):378-384
PURPOSE OF REVIEW: To highlight the potential importance of glycation as an atherogenic modification of LDL in both diabetic and nondiabetic people. RECENT FINDINGS: Small dense LDL which is known to be most closely associated with atherogenesis is more susceptible to glycation than more buoyant LDL. Glycation and oxidation of LDL appear to be intimately associated. SUMMARY: Glycation of LDL occurs chiefly due to the nonenzymatic reaction of glucose and its metabolites with the free amino groups of lysine in which LDL is rich. Higher concentrations of glycated LDL are present in diabetic than in nondiabetic individuals, but even in the latter, there is generally more circulating glycated LDL than oxidatively modified LDL. Probably, oxidation and glycation of LDL are at least partially interdependent, but both prevent LDL receptor-mediated uptake and promote macrophage scavenger receptor uptake. The recognition that LDL glycation is at least as important as oxidation in atherogenesis may lead to improvements in our understanding of its mechanism and how to prevent it. 相似文献
9.