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31.
Due to its high nutritional value, chickpea is one of the most important and cost-effective legumes for human diet. Nutrient elements, such as Cu, P, K have numerous essential functions for the human metabolism. In this study, association mapping of loci linked to the seed Cu, P and K concentrations were performed on a population consisting of 107 Cicer reticulatum and 73 Cicer arietinum individuals in four environments (two locations x two years). A total of 121,840 SNPs were genotyped across 180 individuals by GBS analysis. The association mapping between the SNP markers and the seed Cu, P, K concentrations were identified and eight SNPs were found to be significantly associated with variations in three nutrient elements in more than two environments This research suggests that association mapping is a useful methodology for the identification of loci controlling the Cu, P and K uptake in chickpea seeds for further association mapping, molecular breeding, and marker-assisted selection and plant breeding studies and provides a broader understanding of the relationship between the investigated Cicer species and the effects of environmental conditions.  相似文献   
32.

Background

We test whether the phenotypic variance of symbionts (Symbiodinium) in corals is closely related with the capacity of corals to acclimatize to increasing seawater temperatures. Moreover, we assess whether more specialist symbionts will increase within coral hosts under ocean warming. The present study is only applicable to those corals that naturally have the capacity to support more than one type of Symbiodinium within the lifetime of a colony; for example, Montastraea annularis and Montastraea faveolata.

Methodology/Principal Findings

The population dynamics of competing Symbiodinium symbiont populations were projected through time in coral hosts using a novel, discrete time optimal–resource model. Models were run for two Atlantic Ocean localities. Four symbiont populations, with different environmental optima and phenotypic variances, were modeled to grow, divide, and compete in the corals under seasonal fluctuations in solar insolation and seawater temperature. Elevated seawater temperatures were input into the model 1.5°C above the seasonal summer average, and the symbiont population response was observed for each location. The models showed dynamic fluctuations in Symbiodinium populations densities within corals. Population density predictions for Lee Stocking Island, the Bahamas, where temperatures were relatively homogenous throughout the year, showed a dominance of both type 2, with high phenotypic variance, and type 1, a high-temperature and high-insolation specialist. Whereas the densities of Symbiodinium types 3 and 4, a high-temperature, low-insolation specialist, and a high-temperature, low-insolation generalist, remained consistently low. Predictions for Key Largo, Florida, where environmental conditions were more seasonally variable, showed the coexistence of generalists (types 2 and 4) and low densities of specialists (types 1 and 3). When elevated temperatures were input into the model, population densities in corals at Lee Stocking Island showed an emergence of high-temperature specialists. However, even under high temperatures, corals in the Florida Keys were dominated by generalists.

Conclusions/Significance

Predictions at higher seawater temperatures showed endogenous shuffling and an emergence of the high-temperature Symbiodinium specialists, even though their phenotypic variance was low. The model shows that sustaining these “hidden” specialists becomes advantageous under thermal stress conditions, and shuffling symbionts may increase the corals'' capacity to acclimatize but not adapt to climatechange–induced ocean warming.  相似文献   
33.
OBJECTIVE: To assess the immunoreactivity of 5 proteins related to basement membrane (BM) and extracellular matrix in order to investigate whether any of them correlates with differentiation of prostatic adenocarcinoma (PAc). Two of these markers are collagen type IV (Col IV), the collagenous component of basement membrane, and fibronectin (Fn), an adhesion protein in extracellular matrix. Others are matrix metalloproteinase-9 (MMP-9), a type IV collagenase, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), which has a high affinity for MMP-9, and 67-kd laminin receptor (67LR), which belongs to the non-integrin laminin binding receptor family. STUDY DESIGN: Forty-three PAc cases with Gleason scores ranging between 5 and 10 and 10 benign prostatic hyperplasia (BPH) cases, the control group, were included in the study. Formalin-fixed and paraffin-embedded tissue slides from each case were immunostained with the avidin-biotin-peroxidase method. Immunoreactivity was determined by means of a scoring system similar to the Gleason scoring system. RESULTS: Overexpression of Col IV, Fn, 67LR and MMP-9 was detected in PAc as compared with BPH, whereas no difference was determined in TIMP-1 expression. Among these, only 67LR correlated statistically with Gleason score. CONCLUSION: Expression of 67LR in tumor cells was significantly increased in parallel to tumor grade. This may be useful in microscopic evaluation of PAc.  相似文献   
34.
Previous studies have described the paw preference and asymmetry in dog brains, based on experimental studies. The purpose of the present study is to investigate a possible association between callosal anatomy and paw preference in dogs. The midsagittal area of the dog corpus callosum was measured in its entirety and in six subdivisions in a sample of 21 brains obtained from 9 male and 12 female mongrel dogs which had paw preference testing. The present study showed significant paw differences in dog corpus callosum. A posterior segment of the callosum, the isthmus, was significantly larger in the right pawedness than the left.  相似文献   
35.

Background

Prophylactic treatment with N-acetylcysteine (NAC) for 3 months or more is associated with a reduction in the frequency of exacerbations of chronic obstructive pulmonary disease (COPD). This raises the question of whether treatment with NAC during an acute exacerbation will hasten recovery from the exacerbation.

Methods

We have examined this in a randomised, double-blind, placebo controlled trial. Subjects, admitted to hospital with an acute exacerbation of COPD, were randomised within 24 h of admission to treatment with NAC 600 mg b.d. (n = 25) or matching placebo (n = 25). Treatment continued for 7 days or until discharge (whichever occurred first). To be eligible subjects had to be ≥ 50 years, have an FEV1 ≤ 60% predicted, FEV1/VC ≤ 70% and ≥ 10 pack year smoking history. Subjects with asthma, heart failure, pneumonia and other respiratory diseases were excluded. All subjects received concurrent treatment with prednisone 40 mg/day, nebulised salbutamol 5 mg q.i.d and where appropriate antibiotics. FEV1, VC, SaO2 and breathlessness were measured 2 hours after a dose of nebulised salbutamol, at the same time each day. Breathlessness was measured on a seven point Likert scale.

Results

At baseline FEV1 (% predicted) was 22% in the NAC group and 24% in the control group. There was no difference between the groups in the rate of change of FEV1, VC, SaO2 or breathlessness. Nor did the groups differ in the median length of stay in hospital (6 days for both groups).

Conclusions

Addition of NAC to treatment with corticosteroids and bronchodilators does not modify the outcome in acute exacerbations of COPD.  相似文献   
36.
The synthesis of (1S,2R)-1-amino-2-indanol, a key component of HIV protease inhibitor is accomplished in four steps starting from indanone efficiently and with high levels of diastereo- and enantioselectivity. The starting material is converted into 2-acetoxy-1-indanone involving Manganese (III) acetate oxidation . The 2-acetoxyketone is hydrolyzed to 2-hydroxy-1-indanone enantioselectively using Rhizopus oryzae. Selective reduction of 2-hydroxyoxime derivative, derived from the 2-hydroxyketone, gives the amino alcohol up to 98% diastereo- and enantioselectivity.  相似文献   
37.
38.
Forecasts of ecological dynamics in changing environments are increasingly important, and are available for a plethora of variables, such as species abundance and distribution, community structure and ecosystem processes. There is, however, a general absence of knowledge about how far into the future, or other dimensions (space, temperature, phylogenetic distance), useful ecological forecasts can be made, and about how features of ecological systems relate to these distances. The ecological forecast horizon is the dimensional distance for which useful forecasts can be made. Five case studies illustrate the influence of various sources of uncertainty (e.g. parameter uncertainty, environmental variation, demographic stochasticity and evolution), level of ecological organisation (e.g. population or community), and organismal properties (e.g. body size or number of trophic links) on temporal, spatial and phylogenetic forecast horizons. Insights from these case studies demonstrate that the ecological forecast horizon is a flexible and powerful tool for researching and communicating ecological predictability. It also has potential for motivating and guiding agenda setting for ecological forecasting research and development.  相似文献   
39.
The uterosacral ligaments are an important part of the pelvic support system. The objective of this study was to compare the expression of collagen type I and collagen type III in the uterosacral ligament biopsies from women with and without pelvic organ prolapse (POP). The uterosacral ligament biopsies were obtained from women with POP (n = 29) and non-POP subjects (n = 35). Immunohistochemistry for collagen type I and collagen type III was performed on formalin-fixed and paraffin-embedded sections. The two groups were matched for age, body mass index, parity and postmenopausal status. The expression of collagen type I (p < 0.001) and collagen type III (p < 0.0001) differed between women with POP and non-POP subjects. There was decreased expression of collagen type I and increased expression of collagen type III in uterosacral ligaments of women with POP compared with non-POP subjects. This difference indicates a possible relationship between POP and the immunohistochemical expression of collagen type I and collagen type III in uterosacral ligaments.  相似文献   
40.

Introduction

Familial Mediterranean fever (FMF) is an auto-inflammatory disease characterized by recurrent attacks of fever and serositis. Limited data suggest that the prevalence of sacroiliitis is increased in patients with FMF. In our present study, we assessed the prevalence of spondyloarthritis (SpA), including ankylosing spondylitis (AS), among a cohort of FMF patients and their unaffected first-degree relatives (FDRs).

Methods

The current study cohort comprised a consecutive group of 201 unrelated patients with FMF and 319 FDRs (≥ 16 years old). These subjects were examined according to a standard protocol.

Results

A total of 157 FMF patients (78.1%) and 233 (73%) unaffected FDRs reported back pain. Fifteen FMF patients (7.5%) and nine unaffected FDRs fulfilled the modified New York (mNY) criteria for AS. One additional FDR with AS was identified after review of the medical records. None of the FMF patients with AS was HLA-B27 positive. The allele frequency of M694V among the FMF patients with radiographic sacroiliitis was significantly higher in comparison with those without sacroiliitis (OR 4.3). When compared with the general population, the risk ratios for SpA and AS among the FDRs of our FMF patients were 3.3 (95% CI; 2.0 to 5.5) and for AS 2.9 (95% CI; 1.3 to 6.4), respectively.

Conclusions

Our study suggests that a) factors other than HLA-B27 play a role in the association of FMF and SpA/AS; b) MEFV gene variations may be one of the geographic/region-specific potential pathogenetic links between these two disorders in the Turkish population.  相似文献   
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