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81.
OBJECTIVE: To evaluate the cytocellularity and histocellularity of lobular carcinoma (LC) and the relationship to high false negative results of fine needle aspiration cytology (FNAC). STUDY DESIGN: In this retrospective study, cellularity was studied in 60 cases of classic LC, LC variants and lobular carcinoma in situ, comparing cytologic smears to their corresponding histologic sections. The cytologic smears were grouped into acellular, low, moderate and high categories, and the histologic sections were grouped into low, moderate and high categories. RESULTS: Malignancy or suspicion of malignancy was diagnosed in 78% of cases. Overall cytocellularity showed acellularity or low cellularity in 60% of cases, while overall histocellularity showed moderate or high cellularity in 95% of cases. When the cytocellularity was moderate or high, the corresponding histocellularity always showed moderate or high histocellularity. When the cytocellularity was low, the corresponding histology showed low histocellularity in 6.3% of cases. Thus, in acellular and low cellular aspirations, corresponding histocellularity may not be the contributing factor toward low cellular yield. In this study, 22% of cases were diagnosed as false negative, 40% were diagnosed as suspicious, and 38% were called positive. Only 17% of positive cases were diagnosed as LC. A large number of LC were misdiagnosed by FNAC as duct cell carcinoma, and most cases of low histocellularity were of the classic type. CONCLUSION: The results of this study suggest that in the majority of cases of LC, cellular yield of FNAC is disproportionately lower than expected when compared to the corresponding histocellularity. Awareness of modest cellularity and subtle cytologic features will aid in the correct preoperative diagnosis of LC, and false negative diagnoses can be minimized.  相似文献   
82.
83.
In this paper, the authors used cluster analysis method to study the corticolous lichen community structure in forest ecosystem of eastern AltayMts of Xinjiang according to the on the spot investigation results in many year. The results show that in this Mts the lichen species which can be divided into four communities: (1 ) Calicium abietinum Pers + Tephromela atra (Hundson) community; (2) Leptogium saturninum (Dicks. ) + Lecidea elabens Fr. community; (3) Parmelia sulcata Tayl. apud Mack + Ramalina farnacea (L. ) Ach community; (4) Caloplaca flavorubescens + Phaeophyscia nigricans (Flk. ) community. We also were compared the species diversity, similarity and evenness index of differentcommunities.  相似文献   
84.
地衣是由低等植物中的藻类与菌类中的真菌和兰细菌共生而成的一群特殊的植物。由于耐寒耐旱对生活中的养分要求不高,在养纷贫瘠、环境恶劣的高山寒漠、平原、戈壁和沙漠中地衣都能生长,因而广泛地分布和生长在不同的生态环境中。有关新疆地衣方面的研究报道集中在物种分类水平上,对于地衣群落结构方面的研究比较少。因此,我们应用多元分析中的主分量分析及聚类分析方法对分布在天山森林生态系统中树生地衣植物群落进行数量分类并对群落结构物种多样性、相似性和均匀度等群落参数进行了比较系统的研究。结果表明, 在西部天山不同森林生态系统中树生地衣群落的分布与海拔高度和树种有密切的关系, 不同海拔的不同类型的森林生态系统中分布着不同种类的树生地衣植物。 根据多元分析结果和生境的综合特征,该地区的树生地衣可划分为4种类型: 1) 茎口果粉衣+金黄茶衣群丛Chaenotheca stemonea+Candellaria aurella Association; 2)叉小孢衣+裸扁枝衣+粉唇蜈蚣衣群丛Bryoria furcellata+Evernia esorediosa+Physcia tribacoides Association; 3)亚广开梅衣+槽梅衣+疑小梅衣群丛Parmelia fertilis+Parmelia sulcata+Parmeliopsis ambigua Association; 4)睫毛黑蜈蚣衣+黑蜈蚣衣群丛Phaeophyscia ciliata+Phaeophyscia nigricans Association。其群落多样性指数以亚广开梅衣+槽梅衣+疑小梅衣群丛为最高 (1.920), 叉小孢衣+裸扁枝衣+粉唇蜈蚣衣群丛为最低 (1.562)。  相似文献   
85.
86.
Annona muricata has been used in folk medicine for the treatment of cancer and tumors. This study evaluated the chemopreventive properties of an ethyl acetate extract of A. muricata leaves (EEAML) on azoxymethane-induced colonic aberrant crypt foci (ACF) in rats. Moreover, the cytotoxic compound of EEAML (Annomuricin E) was isolated, and its apoptosis-inducing effect was investigated against HT-29 colon cancer cell line using a bioassay-guided approach. This experiment was performed on five groups of rats: negative control, cancer control, EEAML (250 mg/kg), EEAML (500 mg/kg) and positive control (5-fluorouracil). Methylene blue staining of colorectal specimens showed that application of EEAML at both doses significantly reduced the colonic ACF formation compared with the cancer control group. Immunohistochemistry analysis showed the down-regulation of PCNA and Bcl-2 proteins and the up-regulation of Bax protein after administration of EEAML compared with the cancer control group. In addition, an increase in the levels of enzymatic antioxidants and a decrease in the malondialdehyde level of the colon tissue homogenates were observed, suggesting the suppression of lipid peroxidation. Annomuricin E inhibited the growth of HT-29 cells with an IC50 value of 1.62 ± 0.24 μg/ml after 48 h. The cytotoxic effect of annomuricin E was further substantiated by G1 cell cycle arrest and early apoptosis induction in HT-29 cells. Annomuricin E triggered mitochondria-initiated events, including the dissipation of the mitochondrial membrane potential and the leakage of cytochrome c from the mitochondria. Prior to these events, annomuricin E activated caspase 3/7 and caspase 9. Upstream, annomuricin E induced a time-dependent upregulation of Bax and downregulation of Bcl-2 at the mRNA and protein levels. In conclusion, these findings substantiate the usage of A. muricata leaves in ethnomedicine against cancer and highlight annomuricin E as one of the contributing compounds in the anticancer activity of A. muricata leaves.  相似文献   
87.

Background

This trial was conducted to evaluate the safety and immunogenicity of two virosome formulated malaria peptidomimetics derived from Plasmodium falciparum AMA-1 and CSP in malaria semi-immune adults and children.

Methods

The design was a prospective randomized, double-blind, controlled, age-deescalating study with two immunizations. 10 adults and 40 children (aged 5–9 years) living in a malaria endemic area were immunized with PEV3B or virosomal influenza vaccine Inflexal®V on day 0 and 90.

Results

No serious or severe adverse events (AEs) related to the vaccines were observed. The only local solicited AE reported was pain at injection site, which affected more children in the Inflexal®V group compared to the PEV3B group (p = 0.014). In the PEV3B group, IgG ELISA endpoint titers specific for the AMA-1 and CSP peptide antigens were significantly higher for most time points compared to the Inflexal®V control group. Across all time points after first immunization the average ratio of endpoint titers to baseline values in PEV3B subjects ranged from 4 to 15 in adults and from 4 to 66 in children. As an exploratory outcome, we found that the incidence rate of clinical malaria episodes in children vaccinees was half the rate of the control children between study days 30 and 365 (0.0035 episodes per day at risk for PEV3B vs. 0.0069 for Inflexal®V; RR  = 0.50 [95%-CI: 0.29–0.88], p = 0.02).

Conclusion

These findings provide a strong basis for the further development of multivalent virosomal malaria peptide vaccines.

Trial Registration

ClinicalTrials.gov NCT00513669  相似文献   
88.
Abstract

Synthesis of nanoparticles using biodegradable source is safer and echo-friendly. Here, we describe the synthesis of polycrystalline silver nanocrystals using Citrus sinensis acting as both reducing and capping agents. After exposing the silver ions to orange extract, rapid reduction of silver ions led to the formation of stable silver nanocrystals due to the reducing and stabilizing properties of orange fruit juice. The synthesized silver nanocrystals were characterized using various analytical techniques like UV–vis spectroscopy, X-ray diffraction (XRD), dynamic light scattering (DLS), scanning electron microscope (SEM) and transmission electron microscopy (TEM). The biochemical activity of the synthesized nanocrystals was studied in the light of affinity to bovine serum albumin using several biophysical methods like absorbance, fluorescence and circular dichroism spectroscopy. Cytotoxic activity of these nanocrystals was also studied against Hep-2 cell line using fluorescence microscopy. It was also found that the synthesized nanocrystals can sense mercuric ion down to 50?µM in the presence of a number of cations. Furthermore, we established that the silver nanoparticles can effectively catalyse the reduction of methylene blue by ascorbic acid. The present study will enrich our knowledge on the chemical and biochemical activities of green-synthesized silver nanocrystals.  相似文献   
89.
Breast cancer is a complex heterogeneous disease involving genetic and epigenetic alterations in genes encoding proteins that are components of various signaling pathways. Candidate gene approach have identified association of genetic variants in the Wnt signaling pathway genes and increased susceptibility to several diseases including breast cancer. Due to the rarity of somatic mutations in key genes of Wnt pathway, we investigated the association of genetic variants in these genes with predisposition to breast cancers. We performed a case-control study to identify risk variants by examining 15 SNPs located in 8 genes associated with Wnt signaling. Genotypic analysis of individual locus showed statistically significant association of five SNPs located in β-catenin, AXIN2, DKK3, SFRP3 and TCF7L2 with breast cancers. Increased risk was observed only with the SNP in β-catenin while the other four SNPs conferred protection against breast cancers. Majority of these associations persisted after stratification of the cases based on estrogen receptor status and age of on-set of breast cancer. The rs7775 SNP in exon 6 of SFRP3 gene that codes for either arginine or glycine exhibited very strong association with breast cancer, even after Bonferroni''s correction. Apart from these five variants, rs3923086 in AXIN2 and rs3763511 in DKK4 that did not show any association in the overall population were significantly associated with early on-set and estrogen receptor negative breast cancers, respectively. This is the first study to utilize pathway based approach to identify association of risk variants in the Wnt signaling pathway genes with breast cancers. Confirmation of our findings in larger populations of different ethnicities would provide evidence for the role of Wnt pathway as well as screening markers for early detection of breast carcinomas.  相似文献   
90.
Parental participation is a key factor in the prevention and management of childhood obesity, thus parental recognition of weight problems is essential. We estimated parental perceptions and their determinants in the Emirati population. We invited 1541 students (grade 1–12; 50% boys) and their parents, but only 1440 (6–19 years) and their parents consented. Of these, 945 Emirati nationals provided data for analysis. Anthropometric and demographic variables were measured by standard methods. CDC BMI percentile charts for age and sex were used to classify children’s weight. Parental perception of their children’s weight status (underweight, normal, and overweight/obese) was recorded. Logistic regression analyses were used to identify independent predictors of parental perceptions of children’s weight status. Of all parents, 33.8% misclassified their children’s’ weight status; underestimating (27.4%) or overestimating (6.3%). Misclassification was highest among parents of overweight/obese children (63.5%) and underweight (55.1%) children. More importantly, parental perceptions of their children being overweight or obese, among truly overweight/obese children, i.e. correct identification of an overweight/obese child as such, were associated with the true child’s BMI percentile (CDC) with an OR of 1.313 (95% CI: 1.209–1.425; p<0.001) per percentile point, but not age, parental education, household income, and child’s sex. We conclude that the majority of parents of overweight/obese children either overestimated or, more commonly, underestimated children’s weight status. Predictors of accurate parental perception, in this population, include the true children’s BMI, but not age, household income, and sex. Thus, parents having an incorrect perception of their child’s weight status may ignore otherwise appropriate health messages.  相似文献   
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