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111.
目的 建立大鼠血浆中栀蒡热毒平方有效组分中栀子苷、牛蒡子苷和黄芩苷的HPLC血药浓度测定方法.方法 血浆样品采用甲醇-乙腈(1∶ 1)沉淀蛋白,HPLC测定血药浓度.色谱柱为Diamonsil C18柱(4.6 mm×150 mm, 5 μm),流动相乙腈-0.2%磷酸水梯度洗脱,流速1.0 mL/min,检测波长238 nm和278 nm.结果 各成分的最低检测浓度(S/N>3)在0.23~0.32 mg/L,平均回收率均在85%以上,日内、日间精密度及稳定性的RSD均小于10%.结论 该方法简便、准确,可作为栀蒡热毒平方血药浓度定量分析方法.  相似文献   
112.

INTRODUCTION

Published colorectal cancer surgery data suggest no role for the analysis of the anastomotic doughnuts following anterior resection. The usefulness of routine histological analysis of the upper gastrointestinal doughnut is not clear. Our study assessed the impact of cancer involvement of the doughnut on clinical practice. Factors associated with doughnut involvement and the effect on patients'' survival were also analysed.

PATIENTS AND METHODS

The clinicopathological details of 462 patients who underwent potentially curative oesophagogastrectomy for cancer with a stapled anastomosis between 1994 and 2006 in two specialist centres were retrospectively analysed. Univariate, multivariate and survival analyses were carried out.

RESULTS

Approximately 5% of doughnuts (22 of 462) were histologically involved with cancer. Microscopic involvement of the proximal resection margin, local lymph node metastasis and lymphatic invasion within the main resected specimen were independently associated with doughnut involvement (all P < 0.05). However, these three factors taken together failed to predict doughnut involvement. Doughnut involvement was an independent adverse prognostic factor for overall survival (P = 0.0013).

CONCLUSIONS

In contrast to findings in colorectal surgery, doughnut involvement with cancer appears to have useful prognostic information following oesophagogastrectomy. Routine histological analysis of upper gastrointestinal doughnuts is justified. Doughnut involvement could potentially strengthen the indications for adjuvant therapy in the future.  相似文献   
113.

Introduction

Breast gangrene has been reported as a complication following puerperal sepsis, breast surgery, nipple piercings, warfarin toxicity, etc. We report a case of primary breast gangrene in an HIV-positive individual which, to the best of our knowledge, is the first of its kind.

Case report

A 40-year-old previously healthy woman presented with fulminating left breast gangrene. She was detected to be HIV positive. Mastectomy was performed. The detailed management of the condition is discussed.

Conclusion

Severe necrotising infections may be initial manifestations of HIV infection and patients with such infections should be screened for HIV.  相似文献   
114.
子宫结合带(JZ)是MRI上显示的子宫壁正常结构,JZ在MRI上呈低信号。妊娠期以外的子宫结合带是依赖雌激素的周期性调控来控制子宫的收缩运动的,除此之外,许多生物因子都参与了JZ的调节,如CX43、干扰素因子IFNγ、细胞活素和生长因子等。JZ与子宫肌瘤、子宫内膜异位症、子宫腺肌症、妊娠期并发症、不孕、胚胎植入等的发生均有关,其相关研究现在主要聚集在MRI方面的研究,本文综述了子宫结合带的调节因素及相关疾病。  相似文献   
115.
Certain neurobehavioral deficiencies associated with Turner Syndrome have been attributed to brain volumetric abnormalities, particularly of the amygdala. Haplo-insufficiency of a non-dosage compensated gene or genes on the X chromosome has been hypothesized to be the cause of the neuroanatomical defect. We examined gene expression levels of 6,628 genes in developing amygdalae of late-stage embryos of a mouse model for Turner Syndrome. In total, 161 genes show significant differences in expression level between TS and normal female amygdala. In silico pathway analysis of both X-linked and autosomal mis-regulated genes suggests that modulation of Wnt signaling is a critical factor in the normal growth and development of the amygdala. Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.  相似文献   
116.
117.
Despite abundant examples of both adaptation at the level of phenotype and Darwinian selection at the level of genes, correlations between these two processes are notoriously difficult to identify. Positive Darwinian selection on genes is most easily discerned in cases of genetic conflict, when antagonistic evolutionary processes such as a Red Queen race drive the rate of nonsynonymous substitution above the neutral mutation rate. Genomic imprinting in mammals is thought to be the product of antagonistic evolution coincident with evolution of the placenta, but imprinted loci lack evidence of positive selection likely because of the ancient origin of viviparity in mammals. To determine whether genetic conflict is a general feature of adaptation to placental reproduction, we performed comparative evolutionary analyses of the insulin-like growth factor II (IGF2) gene in teleost fishes. Our analysis included several members of the order Cyprinodontiformes, in which livebearing and placentation have evolved several times independently. We found that IGF2 is subject to positive Darwinian selection coincident with the evolution of placentation in fishes, with particularly strong selection among lineages that have evolved placentation recently. Positive selection is also detected along ancient lineages of placental livebearing fishes, suggesting that selection on IGF2 function is ongoing in placental species. Our observations provide a rare example of natural selection acting in synchrony at the phenotypic and molecular level. These results also constitute the first direct evidence of parent-offspring conflict driving gene evolution.  相似文献   
118.
Vocteer is a university and community support agency collaborative program that matches undergraduate and graduate students with persons diagnosed with severe psychiatric disabilities in community-based volunteer positions. The program aims to improve self-esteem, community inclusion, and vocational skills of program participants. In addition, Vocteer helps participants develop skills necessary for employment or independent volunteering. The program, reports of participant satisfaction, and findings are described. Reports from the literature are presented and provide support for further exploration and development of such programs.  相似文献   
119.
Existing asthma therapies are not always able to achieve disease control. The addition of tiotropium bromide to inhaled corticosteroids might be effective in improving disease outcome. This paper discusses the results of a study evaluating the effects of tiotropium bromide added to inhaled corticosteroids when compared to other regimens in patients with uncontrolled asthma. The addition of tiotropium to the current inhaled corticosteroid dose is comparable to the addition of salmeterol: both are more effective in achieving disease control versus doubling the inhaled corticosteroid dose. It is well worth investigating the effects of tiotropium in asthma that is not adequately controlled with higher doses of inhaled corticosteroids.  相似文献   
120.

Background  

Within the last decade there has been a growth in the call-centre industry in the UK, with a growing awareness of the voice as an important tool for successful communication. Occupational voice problems such as occupational dysphonia, in a business which relies on healthy, effective voice as the primary professional communication tool, may threaten working ability and occupational health and safety of workers. While previous studies of telephone call-agents have reported a range of voice symptoms and functional vocal health problems, there have been no studies investigating the use and impact of vocal performance in the communication industry within the UK. This study aims to address a significant gap in the evidence-base of occupational health and safety research. The objectives of the study are: 1. to investigate the work context and vocal communication demands for call-agents; 2. to evaluate call-agents' vocal health, awareness and performance; and 3. to identify key risks and training needs for employees and employers within call-centres.  相似文献   
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