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941.
OBJECTIVES: To assess the ability of anthropometric measurements to identify young women at risk of developing diabetes, hypertension and heart disease in the future and to compare cut-off points for common anthropometric measures established with receiver-operating characteristic (ROC) curves with those reported in the literature. DESIGN: Cross-sectional study. SUBJECTS: Eight hundred and two young Mexican women living in semi-urban poverty. MEASUREMENTS/METHODS: The ability of anthropometric measures of fatness and fat distribution (body mass index (BMI), summed skinfold thickness (SST), waist circumference (WC), waist-to-hip ratio (WHR), conicity index (CI), abdominal volume index (AVI)) to predict risk of future disease (pre-diabetes: fasting blood glucose 100-126 mg dl-1; pre-hypertension: systolic blood pressure 120-139 mmHg and/or diastolic blood pressure 80-89 mmHg; hypertriglyceridaemia: triglycerides > or =150 mg dl-1; or a combination of risk factors) was assessed using ROC curve analysis. RESULTS: Twenty-three of the 802 women who were interviewed had incomplete data and 50 (6.4%) were eliminated from the analysis due to hypertension and/or diabetes. Mean age of the remaining 729 women was 29.6 +/- 5.4 years and mean BMI was 27.7 +/- 4.5 kg m-2. There were no significant differences in the area under the ROC curve for BMI, WC, AVI or SST for any of the four outcomes. However, these indices performed significantly better than WHR and CI (P < 0.05). The BMI cut-off points that maximised sensitivity and specificity for the four outcomes were in the range of 27.7-28.4 kg m-2, and for WC were 89.3-91.2 cm. To detect 90% of the cases of any metabolic alteration, the necessary BMI cut-off was 26.1 kg m-2. Younger women (<25 years) were at greater risk than older women for a given BMI increment (P < 0.05). CONCLUSIONS: We found that BMI and WC cut-off points commonly used for the identification of risk of existing disease were also appropriate in this population for the identification of risk in the future among women without diabetes or hypertension. The early identification of at-risk individuals, prior to the onset of disease, is fundamental particularly in the context of a country with scarce resources that is rapidly undergoing nutrition transition.  相似文献   
942.
A 10 year-old, spayed female Domestic Short-Haired (DSH) cat was diagnosed with a large primary uveal melanoma and exenteration was recommended. Thoracic radiographs, abdominal ultrasonography, and complete blood count and serum biochemistry panel did not reveal any abnormality compatible with metastatic disease and surgery was performed. Histopathologic study of the eye confirmed a diffuse iris melanoma. Five months later, the cat presented with a lameness of the right anterior extremity. On physical exam the right elbow was swollen and painful. Radiographs showed a severe osteolysis of the radial head and proximal diaphysis. Fine needle aspiration of the radius head identified a round cell neoplasm with scattered cells containing intracytoplasmatic pigmented granules, compatible with metastatic melanoma. The owners decided not to treat the patient with chemotherapy and declined a biopsy. Two months later, the cat died and necropsy was performed confirming bone metastasis of the uveal melanoma. A diagnosis of generalized metastasis from primary diffuse iris melanoma was made. This report describes, for the first time, long bone metastasis from an uveal melanoma in a cat.  相似文献   
943.
In this study, to determine the prevalence of swine toxoplasmosis, 1754 pigs from different regions of Poland were tested for IgG antibodies by an in-house ELISA technique based on native Toxoplasma lysate antigen. Seropositive individuals were found in 19.2% of the examined population. The diagnostic usefulness of three T. gondii recombinant antigens (rMAG1, rSAG1, and rGRA7), either individually or in cocktails (M1: rMAG1 + rSAG1; M2: rMAG1 + rGRA7; M3: rSAG1 + rGRA7; M4: rMAG1 + rSAG1 + rGRA7) were also assessed with serum samples from naturally infected pigs by ELISA analysis. Both rSAG1 and rGRA7 antigens detected specific IgG antibodies with a similar sensitivity (85.3% and 81.3%, respectively), whereas the lower sensitivity was obtained for rMAG1 (only 64%). Better results of reactivity were obtained for mixtures of two antigens: M1 (86.7%), M2 (89.3%) and M3 (92%). Furthermore, the reactivity of three antigens cocktail M4 (97.3%) was much higher than that of individual proteins and combinations containing two antigens. These results suggest that the combination of three recombinant antigens might be useful for the serological detection of T. gondii infection in pigs.  相似文献   
944.
Fossil capitula and pollen grains of Asteraceae from the Eocene of Patagonia, southern Argentina, exhibit morphological features recognized today in taxa, such as Mutisioideae and Carduoideae, that are phylogenetically close to the root of the asteracean tree. This fossil supports the hypothesis of a South American origin of Asteraceae and an Eocene age of divergence and suggests that an ancestral stock of Asteraceae may have formed part of a geoflora developed in southern Gondwana before the establishment of effective dispersal barriers within this landmass.  相似文献   
945.
Two types of live attenuated vaccines have been used worldwide for the control of infectious laryngotracheitis virus (ILTV): 1) chicken embryo origin (CEO) vaccines; and 2) tissue culture origin vaccines (TCO). However, the disease persists in spite of extensive use of vaccination, particularly in areas of intense broiler production. Among the factors that may influence the efficiency of ILTV live attenuated vaccines is a possible interference of Newcastle Disease virus (NDV) and infectious bronchitis virus (IBV) vaccines with the protection induced by ILTV vaccines. The protection induced by CEO and TCO vaccines was evaluated when administered at 14 days of age alone or in combination with the B1 type strain of NDV (B1) and/or the Arkansas (ARK) and Massachusetts (MASS) serotypes of IBV vaccines. Two weeks after vaccination (28 days of age), the chickens were challenged with a virulent ILTV field strain (63140 isolate, group V genotype). Protection was evaluated at 5 and 7 days postchallenge by scoring clinical signs and quantifying the challenge virus load in the trachea using real-time PCR (qPCR). In addition, the viral load of the vaccine viruses (ILTV, NDV, and IBV) was quantified 3 and 5 days postvaccination also using qPCR. The results of this study indicate that the NDV (B1) and IBV (ARK) vaccines and a multivalent vaccine constituted by NDV (B1) and IBV (ARK and MASS) did not interfere with the protection induced by the CEO ILTV vaccine. However, the NDV (BI) and the multivalent (B1/MASS/ARK) vaccines interfered with the protection induced by the TCO vaccine (P < 0.05). Either in combination or by themselves, the NDV and IBV vaccines decreased the tracheal replication of the TCO vaccine and the protection induced by this vaccine, since the ILTV-vaccinated and -challenged chickens displayed significantly more severe clinical signs and ILTV load (P < 0.05) than chickens vaccinated with the TCO vaccine alone. Although NDV and IBV challenges were not performed, the antibody responses elicited by NDV and/or the IBV vaccinations were significantly reduced (P < 0.05) when applied in combination with the CEO vaccine.  相似文献   
946.
对广西主要作物种植区土壤进行调查研究,结果表明:甘蔗、木薯、大豆和花生的缺硫土壤分别占41.3%、38.5%、37.1%和31.6%。施用硫肥后,甘蔗、木薯、大豆和花生分别平均增产7.4%。11.1%、5.2%~7.9%、6.6%~8.7%和7.1%~9.5%。施用元素硫肥与施用硫酸根态硫肥的增产效果基本相当。甘蔗、木薯、大豆和花生对硫的吸收量约为50~60kg/hm^2.30-35kg/hm^2,22-28kg/hm^2和23-30kg/hm^2。  相似文献   
947.
广西桉树种植区土壤条件及其可持续开发的思考   总被引:1,自引:0,他引:1  
作为广西3大造林树种之一,桉树具有速生丰产、适应性广、病虫害少、用途广泛的特点,但长期种植会引起土壤肥力衰退,严重影响种植区可持续生产。通过对田林、钦州、扶绥3个桉树种植区的土壤条件、桉树生长量及其对养分的吸收量所作的分析显示,平衡施肥可有效弥补因桉树砍伐所带走的矿质养分,维持树体养分平衡,是营造桉树丰产林、实现种植区可持续生产的重要手段。  相似文献   
948.
BACKGROUND: A single nucleotide polymorphism in the mitochondrial cytochrome b gene confers resistance to strobilurin (QoI) fungicides in phytopathogenic fungi. Recent studies have revealed worrying levels of resistance to strobilurins in Podosphaera fusca (Fr.) U Braun & N Shishkoff comb. nov. [ = Sphaerothecafusca (Fr.) S Blumer], the main causal agent of cucurbit powdery mildew in Spain. In the present study the underlying resistance mechanism to QoI fungicides in the Spanish populations of P. fusca was investigated. RESULTS: Analysis of the Q(o) domains of cytochrome b in a collection of isolates revealed that none of the typical mutations conferring resistance to QoI, including the G143A and F129L substitutions, was present in the QoI-resistant isolates. Moreover, although different amino acid polymorphisms were observed in the two regions spanning the Q(o) site, none of them consistently distinguished QoI-resistant from QoI-sensitive strains. Exposure to salicylhydroxamic acid (SHAM), a specific inhibitor of alternative oxidase, in the presence of trifloxystrobin did not have any effect on QoI resistance, ruling out alternative respiration as the mechanism of resistance. Sensitivity tests to a battery of respiration inhibitors revealed high levels of cross-resistance to all Qo-inhibitors tested but not to Qi-inhibitors, these features resembling those of a target-site-based resistance. CONCLUSIONS: The results indicate that the mechanism responsible for QoI resistance in P. fusca is not linked to typical mutations in cytochrome b gene and that the absence of the G143A substitution cannot be explained by an intron following codon 143. These are important observations, especially in relation to the possible molecular diagnosis of resistance.  相似文献   
949.
Control of IBR and BVD should be possible in Europe. Effective vaccines and reliable tools for monitoring are available. Systematic approach and strict implementation of control measures are essential. Voluntary or mandatory programs are ongoing on regional or national level in a lot of countries. Successful programs put pressure on surrounding regions/countries to initiate control program as well.  相似文献   
950.
ABSTRACT A degree of genetic diversity may exist among Verticillium dahliae isolates within vegetative compatibility groups (VCGs) that bears phytopathological significance and is worth investigating using molecular tools of a higher resolution than VCG characterization. The molecular variability within and among V. dahliae VCGs was studied using 53 artichoke isolates from eastern-central Spain, 96 isolates from cotton, 7 from cotton soil, and 45 from olive trees in countries of the Mediterranean Basin. Isolates were selected to represent the widest available diversity in cotton- and olive-defoliating (D) and -nondefoliating (ND) pathotypes, as well as for VCG. The VCG of 96 cotton and olive isolates was determined in this present study. Molecular variability among V. dahliae isolates was assessed by fluorescent amplified fragment length polymorphism (AFLP) analysis and by polymerase chain reaction (PCR) assays for DNA fragments associated with the D (462 bp) and ND (824 bp) pathotypes, as well as a 334-bp amplicon associated with D pathotype isolates but also present in some VCG2B isolates. Isolates from cotton were in VCG1A, VCG1B, VCG2A, VCG2B, and VCG4B and those from olive trees were in VCG1A, VCG2A, and VCG4B. Artichoke isolates included representatives of VCG1A, VCG2A, VCG2B (including a newly identified VCG2Ba), and VCG4B. AFLP data were used to generate matrixes of genetic distance among isolates for cluster analysis using the neighbor-joining method and for analysis of molecular variance. Results demonstrated that V. dahliae isolates within a VCG subgroup are molecularly similar, to the extent that clustering of isolates correlated with VCG subgroups regardless of the host source and geographic origin. VCGs differed in molecular variability, with the variability being highest in VCG2B and VCG2A. For some AFLP/VCG subgroup clusterings, V. dahliae isolates from artichoke grouped in subclusters clearly distinct from those comprising isolates from cotton and olive trees. In addition, VCG2B isolates from artichoke formed two distinct clusters that correlated with PCR markers of 334 bp (VCG2B(334)) or 824 bp (VCG2B(824)). Artichoke isolates in the VCG2B(334)/2beta(334) cluster were molecularly similar to isolates of VCG1A. The molecular difference found among artichoke isolates in VCG2B correlates with virulence of isolates to artichoke and cotton cultivars demonstrated in a previous study.  相似文献   
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