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71.
When intact Toxoplasma trophozoites were stained with isotonic alkaline methylene blue solution, the organelles rich in nucleic acid, i.e., nucleus, free and membrane-bound ribosomes appeared as electron dense areas. When the parasites were incubated with the anti-Toxoplasma antibody and the accessory factor, swelling of the surface membrane occurred first, followed by destruction of the inner structures. In the dye test positive parasites, there were no definite organelles recognizable, as there were in the intact parasites. By the negative staining method, holes (defects) with dark central portions were observed on the surface of the parasites treated with the antibody and the accessory factor, the diameter of the holes measuring about 10–11 nm. These holes, which tended to occur in clusters, were each surrounded by a clear ring. 相似文献
72.
摘要 目的:观察八段锦和五行音乐疗法对新型冠状病毒肺炎(COVID-19)患者负性情绪的疗效。方法:收集孝感市第一人民医院就诊的COVID-19患者40例,采用随机数字表法将40例患者随机分为对照组(n=20)和观察组(n=20),观察组接受八段锦和子午流注理论指导下的择时五行音乐疗法进行干预,对照组保持日常生活方式。两组在干预前、干预2周采用焦虑自评量表(SAS)和抑郁自评量表(SDS)分别评定两组实验对象在实验前和干预后的负性情绪的改变,用患者生活质量量表(QLQ-C30)分别对两组患者进行生活质量的测评。结果:接受八段锦和子午流注理论指导下的择时五行音乐疗法的患者负性情绪明显减低,SAS、SDS评分明显较前明显改善,观察组患者SAS评分、SDS评分较对照组降低程度明显,差异存在统计学差异(P<0.05);干预后观察组、对照组的角色功能、认知功能、情感功能、躯体功能及生活质量评分均明显改善,接受八段锦和子午流注理论指导下的择时五行音乐疗法的患者在角色功能、认知功能、情感功能、躯体功能及生活质量评分方面均优于对照组,差异存在统计学差异(P<0.05)。结论:COVID-19患者通过八段锦和五行音乐疗法能够明显减低负性情绪,此种疗法可有效起到"精神内守,病安从来"的安慰作用。 相似文献
73.
Charles Dewitt Roberts 《Biometrical journal. Biometrische Zeitschrift》1993,35(5):581-587
The use of the negative binomial distribution in both the numerator and denominator in prospective studies leads to an unbiased estimate of the odds ratio and an exact expression for its variance. Sample sizes that minimize the variance of odds ratio estimates are specified. The variance of the odds ratio estimate is shown to be close to the Cramér-Rao lower bound. 相似文献
74.
A. N. Philippou 《Biometrical journal. Biometrische Zeitschrift》1984,26(7):789-794
The negative binomial distribution of order k is introduced and briefly studied. First it is shown that it is a proper probability distribution. Then its probability generating function, mean and variance are derived. Finally it is shown that the number of trials until the rth kth consecutive success (r ≧ 1, k ≧ 1) in independent trials with constant success probability p (0 < p < 1) is distributed as negative binomial distribution of order k. The present paper generalizes results of SHANE (1973), PHILIPPOU and MUWAFI (1982), and PHILIPPOU, GEORGHIOU and PHILIPPOU (1982). 相似文献
75.
Wen-Tao Huang A. K. Md. Ehsanes Saleh 《Biometrical journal. Biometrische Zeitschrift》1987,29(7):857-863
We propose a new class of selection rules for selecting superior models from finite Binomial models. This new class of rules extends the classes of classical rules and shows its superiority to the classical selection rules by some Monte Carlo results. This new class of rules is easier and more flexible to apply than these known classical rules. 相似文献
76.
《Saudi Journal of Biological Sciences》2021,28(11):6289-6296
According Global Cancer Statistics 2020 GLOBOCAN estimates female breast cancer was found as the most commonly diagnosed cancer, with an estimated 2.3 million new cases (11.7%), and the fourth leading cause (6.9%) of cancer death among women worldwide. Identification of new diagnostic marker sharply characterize the tumor feature is intensive need. The present work was performed to investigate the involvement of the INF-γ + 874 T/A gene polymorphism in different breast cancer prognostic factors. Polymorphism detection analysis was performed on 163 subjects from breast cancer patients, 79 with inflamed cells of breast patients and 144 controls. The gene polymorphism was detected using the amplification refractory mutation system- polymerase chain reaction method (ARMS-PCR). The distribution of INF-γ T + 874A gene polymorphism shows strong significant association between INF-γ + 874 T/A genotypes TT in BC patients (ORTT: 6.41 [95% CI = 2.72–15.1] P < 0.0001) as well as strong significant association regarding T allele (ORT: 1.99 [95% CI = 1.43–2.76] P < 0.0001) when compared to the healthy control. In ICB group the strong association was noted with INF-γ + 874 T/A genotypes AT genotype (ORAT: 2.28 [95% CI = 1.22–4.29] P = 0.007). From the different histological BC hormonal markers the human epidermal growth factor receptor 2 (HER2) was showing significant association in INF-γ + 874 T/A genotypes TT (P = 0.03) and recessive model (TT versus AA + AT P = 0.03). Concerning different BC prognostic models, the poor prognostic one of luminal B, (ER+ve PR+ve Her2+ve) show significant association in the host INF-γ + 874 T/A genotype (TT, P = 0.03) and recessive model (TT versus AA + AT P = 0.02) when compared to the good prognostic hormonal status luminal A model, (ER+ve PR+ve Her2-ve). It seems that this is the first study that interested in correlate the INF-γ + 874 T/A gene polymorphisms in Egyptian BC patients. T allele, TT genotype and recessive model of the INF-γ + 874 T/A gene variants were documented as risk factors for BC pathogenesis. It may be used as practical biomarker to guide the BC carcinogenesis and risk process. 相似文献
77.
Osvaldo Loquiha Niel Hens Leonardo Chavane Marleen Temmerman Marc Aerts 《Biometrical journal. Biometrische Zeitschrift》2013,55(5):647-660
Count data are very common in health services research, and very commonly the basic Poisson regression model has to be extended in several ways to accommodate several sources of heterogeneity: (i) an excess number of zeros relative to a Poisson distribution, (ii) hierarchical structures, and correlated data, (iii) remaining “unexplained” sources of overdispersion. In this paper, we propose hierarchical zero‐inflated and overdispersed models with independent, correlated, and shared random effects for both components of the mixture model. We show that all different extensions of the Poisson model can be based on the concept of mixture models, and that they can be combined to account for all different sources of heterogeneity. Expressions for the first two moments are derived and discussed. The models are applied to data on maternal deaths and related risk factors within health facilities in Mozambique. The final model shows that the maternal mortality rate mainly depends on the geographical location of the health facility, the percentage of women admitted with HIV and the percentage of referrals from the health facility. 相似文献
78.
P. A. Lachenbruch 《Biometrical journal. Biometrische Zeitschrift》1991,33(1):41-45
This paper discusses analysis of dispersion tests in tables with spoiled data, that is, where some cells are missing. BENNETT (1987) gave a method for estimating the missing cells in a two-way table and illustrated it with a simple example. This paper uses GLIM to estimate the models and indicates that the General Linear Model performs the computations without need to estimate the missing values. The binomial error model also may be used for this problem, and is the more natural approach to the problem. 相似文献
79.
Zuben P. Brown Takao Arimori Kenji Iwasaki Junichi Takagi 《Journal of structural biology》2018,201(3):247-251
Several gene fusion technologies have been successfully applied to label particular subunits or domains within macromolecular complexes to enable positional mapping of electron microscopy (EM) density maps, but exogenous fusion of a protein domain into the target polypeptide can cause unwanted structural and functional outcomes. Fab fragments from antibodies can be used as labeling reagents during EM visualization without gene manipulation of the target protein, but this method requires a panel of high-affinity antibodies that recognize a wide variety of epitopes. Linear peptide tags and their anti-tag antibodies can be used but they have a limited mapping ability as their placement is usually limited to the terminal regions of a protein. The PA dodecapeptide epitope tag (GVAMPGAEDDVV), forms a tight β-turn in the antigen binding pocket of its antibody (NZ-1). This capability allows for insertion of the PA tag into various surface-exposed loops within a multi-domain cell adhesion receptor, αIIbβ3 integrin. We confirmed that the purified PA-tagged integrin ectodomain fragments can form a stable complex with NZ-1 Fab. Negative stain EM of the various integrin-NZ-1 complexes revealed that a majority of the particles exhibited a clear density corresponding to the NZ-1 Fab; and the positions of the bound Fab were in good agreement with the predicted location of the inserted PA tag. The high-affinity and insertion-compatibility of the PA tag system allowed us to develop a new EM labeling methodology applicable to proteins for which good antibodies are not available. 相似文献
80.
Andrew S. Felts Alice L. Rodriguez Ryan D. Morrison Anna L. Blobaum Frank W. Byers J. Scott Daniels Colleen M. Niswender P. Jeffrey Conn Craig W. Lindsley Kyle A. Emmitte 《Bioorganic & medicinal chemistry letters》2018,28(10):1679-1685
Based on previous work that established fused heterocycles as viable alternatives for the picolinamide core of our lead series of mGlu5 negative allosteric modulators (NAMs), we designed a novel series of 6-(pyrimidin-5-ylmethyl)quinoline-8-carboxamide mGlu5 NAMs. These new quinoline derivatives also contained carbon linkers as replacements for the diaryl ether oxygen atom common to our previously published chemotypes. Compounds were evaluated in a cell-based functional mGlu5 assay, and an exemplar analog 27 was >60-fold selective versus the other seven mGlu receptors. Selected compounds were also studied in metabolic stability assays in rat and human S9 hepatic fractions and exhibited a mixture of P450- and non-P450-mediated metabolism. 相似文献