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1.
血液光谱在疾病诊断中的应用   总被引:3,自引:1,他引:2  
本文介绍光谱技术在血液诊断学研究中的应用原理与研究现状;包括利用光谱技术进行癌症的诊断,白血病的诊断,血液中微量元素与疾病检测的关系等。讨论利用光谱技术进行诊断存在的问题并展望其在疾病诊断上的应用前景。  相似文献   

2.
张勇  杨星科 《昆虫知识》2004,41(4):308-317
跳甲作为叶甲科Chrysomelidae中最大的一个类群具有重要的经济意义。该文简述了跳甲亚科Alticinae的分类研究历史 ,回顾了世界及中国的研究概况 ,从分类地位、族级阶元的划分、支序系统学及分子系统学等方面综述了跳甲亚科的最新研究进展 ,并简要讨论了存在的问题及研究前景  相似文献   

3.
This study focuses on earnings disadvantages experienced by three ethnic groups of Jewish immigrants in Israel. Data were obtained from the 2011 Income Survey gathered by the Israel Central Bureau of Statistics. The findings reveal that when compared to Israeli-born, all ethnic groups are disadvantaged in earnings attainment in the first generation. The earnings disadvantages of immigrants as compared to Israeli-born decrease with the passage of time and become negligible in the second generation. To disentangle the impact on earnings penalty of ethnic origin from that of immigrant status, a procedure for decomposing mean differences between groups is introduced. The analysis reveals that earnings disadvantage among Ashkenazim and Soviet immigrants can be attributed to immigrant status but not to ethnicity. By contrast, earnings penalties among Sephardim immigrants can be attributed to both ethnicity and immigrant status. The implications of the long-lasting effect of ethnicity versus the short-term effect of immigrant status are discussed.  相似文献   

4.
Residents’ health is an important factor affecting social development and harmony. Based on 2010 China Family Panel Studies data of the Institute of Social Science Survey, Peking University and using a multi-classification logit regression model, we analyze the factors that affect the health status of residents in China. These factors include environmental pollution, which is a particularly important factor. Our study found that the impacts of residents’ characteristic variables, external living environment, and living habits vary. As residents age, their health status deteriorates. For the General, Less healthy, and Unhealthy groups, an income of less than CNY 10,000 significantly affects health status; however, when their income is greater than CNY 10,000, it no longer has a significant effect. For the Very unhealthy group, this particular threshold value is CNY 3000. At least one of urban–rural classification and residence registration status is significant, indicating that the urban–rural dual structure as well as the household registration system significantly affects residents’ health status. However, the direction of this effect is uncertain. Cooking water significantly affects the Less healthy and Unhealthy groups, and tap water is more conducive to health. Polluting enterprises within a radius of five kilometers mainly affect the Unhealthy group, but the direction of its impact is contrary to expectations. Smoking and drinking significantly affect the health status of the General, Less healthy, and Unhealthy groups. However, the direction of their impact was contrary to expectations. For the Very unhealthy group, drinking has a significant impact on residents’ health status, but the direction of the impact was again the opposite of what we expected. Smoking has no significant impact on the health status of this group. Exercise significantly affects the Less healthy and Unhealthy groups, but its influence has no obvious trend. Our study shows that living habits have a smaller influence on residents’ health status.  相似文献   

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6.
The weight of evidence does not support the hypothesis that the health status of the population is largely dependent on the quality and quantity of its medical services. Evidence to test this hypothesis is presented in a conceptual model of the relationship between health and disease and their care systems, suggesting that medical care is largely unrelated to the health status of the population.Examples of disease trends and distribution are presented to support the thesis that ecology is the primary determinant of the health status of the populationData from selected epidemiological studies point to poverty and air pollution as key factors in determining the pattern of mortality in the urban eco-system.  相似文献   

7.
At a time when tetravalent conjugate vaccines for meningococcal serogroups A/C/Y/W135 are being formulated the O-acetylation status of their respective capsular polysaccharides has not previously been studied in the UK for all components. Although this has been elucidated for serogroup C, little is known about the O-acetylation status of serogroups W135 and Y. Meningococcal serogroup W135 (n=181) and Y (n=90) isolates submitted to the PHLS Meningococcal Reference Unit in 1996, 2000 and 2001 were investigated for O-acetylation capsular status by dot blot assay. Eight per cent of W135 and 79% of Y isolates respectively were found to be O-acetylated with a similar distribution found in both carrier and case isolates. An increase in O-acetylated W135 isolates was noted between 2000 (0%) and 2001 (21%) which was not due to the introduction of the Hajj associated W135 (ET 37 complex; serosubtype P1.5,2) isolates, all of which were de-O-acetylated. Although the biological relevance of O-acetylation status is unknown for these serogroups, an understanding of O-acetylation status of the respective polysaccharides may provide useful insights into the optimal vaccine formulation.  相似文献   

8.
This paper is a preliminary report of a dental pilot study which was recently conducted with 104 elderly subjects, 77 of whom also participated in a nutrition status survey. The study was comprehensive, including measurements of oral health status, and medical data concerning nutrition status. Also included were questionnaires concerning diet and nutritional habits, and attitudes towards dental care. A literature review is also presented. Statistical analysis reveals correlations between certain food types, (liquid/solid fermentable, slowly dissolving fermentable), and root and coronal decay. The correlation with coronal decay is greater. Some of the data are still undergoing analysis. When all the data are analyzed and available, additional reports will be forthcoming and will describe any other correlations that are found between nutritional and oral health status. Certain new periodontal indices will also be described. The relationships between the oral health status and the nutritional needs of the elderly have not been adequately studied. It is expected that with a broader data base, these relationships will be better understood.  相似文献   

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10.
Fifteen triads of unacquainted men conversed for ten minutes while stress was measured in real time by pulse rate and thumb blood volume (TBV). Salivary measures of testosterone (T), cortisol (C), and the stress-related enzyme alpha-amylase (AA) were measured at the beginning and end of the session. Fully or partially transitive status hierarchies formed in 14 triads. (Highest ranked man was scored 1, lowest 3, with ties allowed.) Ten of the triads participated in Study 1, where nothing was at stake in the casual conversation. Five additional triads were run in Study 2, intended to introduce competition by offering a $20 reward to the man afterward chosen as having led the conversation. Most results from the two studies are similar, suggesting that the $20 reward had little effect. Combining studies, pulse and TBV show that conversation is more stressful than watching a video beforehand. Within the conversation, speaking turns are more stressful than listening turns, especially among the lowest ranked men, less so among those higher in rank. This supports a stress-based mechanism for status allocation among humans. Apparently, human speech is a form of status signaling, homologous with nonlinguistic status signals used by other primates, as posited by the “biosocial model.” The biosocial model also posits that a physiological substrate (T, C, and AA) is related to dominance or status. Predicted effects are not replicated here, except for an inverse relationship between the stress enzyme AA and status. The mostly null results, obtained from conversations where there was little or nothing at stake, suggest that T and C (and their interaction) are not relevant to emergent status in the absence of serious competition.  相似文献   

11.
12.
Early warning of ecological carrying capacity (ECC) is essential for the urbanization process. It provides information on the deterioration of the urban ecological environment and potential hazards and promotes sustainable development. However, research on early warning of ECC in the urbanization process has been limited and mainly focused on a single aspect of ECC, a comprehensive early warning system based on the three perspectives of ecological elasticity (EE), resource carrying (RC), and environmental carrying (EC) is still lacking. Additionally, previous studies did not effectively predict the future evolution trends of ECC and failed to reveal the spatiotemporal evolution characteristics. To address these shortcomings, in this study, we propose a comprehensive early warning indicator of ECC incorporating EE, RC, and EC. The state space technique and back-propagation (BP) neural network model were applied to analyze the spatiotemporal evolution of the warning state in the Dongting Lake area. The results showed that the ECC index decreased from 0.5383 to 0.5364 in 2001–2020, and the risk status was in the range of medium risk. This result was consistent with an analysis of the three subsystems, which indicated that urbanization exceeded the ECC. The early warning index of ECC is predicted to be 0.6257 in 2025. The risk status is predicted to be low risk. From 2001 to 2020, the risk status of counties were significantly different. Most counties in the central area had a low-risk status, and peripheral counties had a medium-risk status. The counties with the most serious risk status were mostly distributed along the edge of the area, in places with higher urbanization rates. Neither the spatial pattern nor the risk status is predicted to change substantially before 2025. Therefore, some targeted measures should be taken to improve the ECC and mitigate the risk.  相似文献   

13.
《Genomics》2022,114(4):110412
Tumors are genetically heterogeneous and many mutations are actually present in subclonal populations. The clonal status of mutations is valuable for accurate prognosis, clinical management. The aim of this study was to identify the clonal status of somatic mutations and systematically evaluate their prognostic values across various cancer types. We totally identified 227 clonal and 432 subclonal mutations contributed to prognosis and demonstrated the importance of clonal status in improving mutation-related clinical guidance. We further developed a customized multi-step approach to identify gene-specific prognostic patterns of clonal status at pan-cancer level and found some cancer-specific prognostic patterns. The ‘subclonal-dependent risk’ subpattern was one of the most common subpatterns, it usually accompanied by high genomic in-stability and high extent of intra-tumor heterogeneity and could be used to improve the accuracy of prognostic analysis. Our results revealed the importance of clonal status, especially subclonal mutation in clinical survival.  相似文献   

14.
During the carcinogenesis of colorectal cancer in about half of the cases K-RAS, while much less frequently B-RAF mutation occur in early adenomas. While K-RAS mutant tumors are more likely present in male patients, B-RAF mutant tumors develop more frequently in females and are independent of the microsatellite status. Colorectal cancers are characterized by EGFR expression; the gene is not mutated, rarely amplified and increased copy number is due to chromosomal polysomy. This phenotype/genotype of colorectal cancer lent support to the introduction of anti-EGFR antibody therapies. For a while positive EGFR expression status of the tumor was the basis of patient selection for these targeted therapies in colorectal cancer. Monotherapies with the two available anti-EGFR antibodies of chemoresistant colorectal cancers resulted in appr. 10% objective response rate, which was independent of the level of EGFR expression. In case of panitumumab it was discovered that the efficacy of this targeted therapy depends on the K-RAS mutant status of the tumors. Furthermore, preliminary data suggest that cetuximab combined with chemotherapy is effective also exclusively in K-RAS wild-type tumors. Based on these data it is safe to say that K-RAS mutant status of colorectal cancer is a negative predictor for EGFR-targeted therapies of colorectal cancer. Accordingly, it is necessary to determine the K-RAS status of colorectal cancer before making therapeutic decisions.  相似文献   

15.
In the report there are present the results of monitoring of the state of immune status in the remote period after the accident at the Chernobyl Nuclear Power Plant among three groups of liquidators, which were from Moscow and the Moscow district, the Northwestern region of Leningrad district and from Krasnoyarsk territory. During the monitoring of the liquidators from different regions there was found phenotype of immune status with regional characteristics. In the Moscow district the clinical displays of immune insufficiency prevail and in the North western region the modifications of immune status prevail among liquidators. In all the groups we could see quantitative and immunoregulatory disbalance with the increase of parameters of cellular activity such as CD95+, HLA-DR+, T-activated lymphocytes, fluctuation cytotoxic cells (CD8+, CD16+), persevering disimmunoglobulinemia with differently directed modification serum of immunoglobulins at decrease B-lymphocytes. By the end of the twenty-year period after the accident we can see a similar phenotype of immune status in all the groups with increasing of the marker of late activation (HLA-DR+) and apoptotic activity (CD95+) and it is potentially dangerous regarding cancerogenesis. According to the basis of long-term monitoring there has been discovered the immune characteristic of proliferative syndrome for the first time. The monitoring of 2004 has revealed a huge similarity immune status at non-malignant growth at significant decrease CD25+ in the Northwestern region and some differences in common IgE.  相似文献   

16.
Communication signals are key regulators of social networks and are thought to be under selective pressure to honestly reflect social status, including dominance status. The odours of dominants and nondominants differentially influence behaviour, and identification of the specific pheromones associated with, and predictive of, dominance status is essential for understanding the mechanisms of network formation and maintenance. In mice, major urinary proteins (MUPs) are excreted in extraordinary large quantities and expression level has been hypothesized to provide an honest signal of dominance status. Here, we evaluate whether MUPs are associated with dominance in wild‐derived mice by analysing expression levels before, during and after competition for reproductive resources over 3 days. During competition, dominant males have 24% greater urinary MUP expression than nondominants. The MUP darcin, a pheromone that stimulates female attraction, is predictive of dominance status: dominant males have higher darcin expression before competition. Dominants also have a higher ratio of darcin to other MUPs before and during competition. These differences appear transient, because there are no differences in MUPs or darcin after competition. We also find MUP expression is affected by sire dominance status: socially naive sons of dominant males have lower MUP expression, but this apparent repression is released during competition. A requisite condition for the evolution of communication signals is honesty, and we provide novel insight into pheromones and social networks by showing that MUP and darcin expression is a reliable signal of dominance status, a primary determinant of male fitness in many species.  相似文献   

17.
Summary The results of a greenhouse and a field experiment to evaluate the nitrogen nutrition status of rice indicate that: (1) first and second most recently natured leaves are sensitive indicators of the nitrogen status of plants; (2) the total nitrogen concentration in these leaves are a better indicator of the nutrient status of plants than are the water-soluble and amide-plus-ammonium nitrogen fractions; and (3) that the best correlation between plant growth and total nitrogen is obtained when these leaves are sampled at the stage of growth between maximum tillering and panicle emergence.  相似文献   

18.
According to the materials of multiyear studies, the author estimates the ecological status of forest lakes in the Omsk Priirtyshye with respect to the phytoplankton development indicators. The species composition, structure, and floristic similarity degree of the phytoplankton of polytypic forest lakes are described. The author also determines the trophic status and water quality of these lakes. It is found that excessive recreation has a negative impact on the ecological status of the lakes.  相似文献   

19.
NDVI曲线与农作物长势的时序互动规律   总被引:69,自引:2,他引:69  
利用气象卫星NOAA AVHRR资料,反演出农作物生育期内每日和旬度的NDVI数据,分析了NDVI时间曲线的波动与农作物生长发育阶段及农作物长势的响应规律,并以华北冬小麦为例,探讨了NDVI在冬小麦中生育期的积分值与农作物单产之间的相互关系。结果表明,利用长时间序列的NDVI数据,结合作物的物候历,可以实现作物长势的遥感监测和产量遥感估算。  相似文献   

20.
Phylogenetic analysis of selected subfamily and family taxa within the Dactylogyroidea indicates that the Ancyrocephalidae Bychowsky, 1937, is unnatural. The family contains both poly- and paraphyletic features. The analysis supports the previous elevation of the Pseudomurraytrematinae to family status and suggests that revision of the Ancyrocephalidae is necessary. Two options for revision are provided; that of returning the taxon to subfamily status within the Dactylogyridae is preferred, requiring a change in status of the Heterotesiidae to a subfamily within the Dactylogyridae.  相似文献   

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