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1.
Summary The individual effects of seven hormones on the in vitro growth rate of different classifications of human mammary epithelium were compared. Hormones used were: 17β-estradiol, estriol, progesterone, hydrocortisone, testosterone, prolactin, and growth hormone. Cell cultures included three established breast cell lines and primary monolayer cultures established form breast fluids and excised mammary tissue from 40 women and 4 men. Specimens comprised three classifications: normal, nonmalignant atypical, and malignant. Growth was quantitated in situ and expressed as population doubling time. Principal findings were: (a) estrogens, prolactin, and growth hormone stimulated growth of normal cells more frequently than growth of malignant cells, whereas testosterone and hydrocortisone stimulated growth of malignant cells more frequently than growth of normal cells; (b) cells cultured from nonmalignant atypias generally showed hormone response profiles intermediate between those of normal and malignant cells; (c) progesterone stimulated the growth of cells from malignant specimens but not the growth of cells from normal and nonmalignant atypical samples. This research was supported by NIAID Research Training Grant 5-TO1-A1-00332-06.  相似文献   
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Abstract

The Westland petrel (Procellaria westlandica) is an endemic New Zealand species and one of the very few burrowing seabird species still breeding on mainland New Zealand. It nests only on a series of coastal ridgelines near to Punakaiki on the West Coast of the South Island. Between 2002 and 2005, surveys were undertaken at 28 of the 29 known colonies. The area occupied by the colonies was 73 ha; most colonies had fewer than 50 burrows, but six colonies had 201–500 burrows and four colonies had more than 1000 burrows. We find that the current breeding range of Westland petrel and the location of individual colonies are similar to those reported in both the 1950s and 1970s. Based on total burrow counts at 28 colonies and burrow occupancy rates determined by annual monitoring, the annual breeding population is estimated to be between 2954 and 5137 breeding pairs.  相似文献   
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Background

Patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) commonly require hospitalization and admission to intensive care unit (ICU). It is useful to identify patients at the time of admission who are likely to have poor outcome. This study was carried out to define the predictors of mortality in patients with acute exacerbation of COPD and to device a scoring system using the baseline physiological variables for prognosticating these patients.

Methods

Eighty-two patients with acute respiratory failure secondary to COPD admitted to medical ICU over a one-year period were included. Clinical and demographic profile at the time of admission to ICU including APACHE II score and Glasgow coma scale were recorded at the time of admission to ICU. In addition, acid base disorders, renal functions, liver functions and serum albumin, were recorded at the time of presentation. Primary outcome measure was hospital mortality.

Results

Invasive ventilation was required in 69 patients (84.1%). Fifty-two patients survived to hospital discharge (63.4%). APACHE II score at the time of admission to ICU {odds ratio (95 % CI): 1.32 (1.138–1.532); p < 0.001} and serum albumin (done within 24 hours of admission) {odds ratio (95 % CI): 0.114 (0.03-0.432); p = 0.001}. An equation, constructed using the adjusted odds ratio for the two parameters, had an area under the ROC curve of 91.3%. For the choice of cut-off, sensitivity, specificity, positive and negative predictive value for predicting outcome was 90%, 86.5%, 79.4% and 93.7%.

Conclusion

APACHE II score at admission and SA levels with in 24 hrs after admission are independent predictors of mortality for patients with COPD admitted to ICU. The equation derived from these two parameters is useful for predicting outcome of these patients.  相似文献   
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HeLa was the first human cell line established (1952) and became one of the most frequently used lines because of its hardiness and rapid growth rate. During the next two decades, the development of other human cell lines mushroomed. One reason for this became apparent during the 1970s, when it was demonstrated that many of these cell lines had been overgrown and replaced by fast-growing HeLa cells inadvertently introduced into the original cultures. Although the discovery of these "HeLa contaminants" prompted immediate alarm, how aware are cell culturists today of the threat of cell line cross-contamination? To answer this question, we performed a literature search and conducted a survey of 483 mammalian cell culturists to determine how many were using HeLa contaminants without being aware of their true identity and how many were not using available means to ensure correct identity. Survey respondents included scientists, staff, and graduate students in 48 countries. HeLa cells were used by 32% and HeLa contaminants by 9% of survey respondents. Most were also using other cell lines; yet, only about a third of respondents were testing their lines for cell identity. Of all the cell lines used, 35% had been obtained from another laboratory instead of from a repository, thus increasing the risk of false identity. Over 220 publications were found in the PubMed database (1969-2004) in which HeLa contaminants were used as a model for the tissue type of the original cell line. Overall, the results of this study indicate a lack of vigilance in cell acquisition and identity testing. Some researchers are still using HeLa contaminants without apparent awareness of their true identity. The consequences of cell line cross-contamination can be spurious scientific conclusions; its prevention can save time, resources, and scientific reputations.  相似文献   
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The aetiology of anti-neutrophil cytoplasmic antibody (ANCA)-associated systemic vasculitis has not been well defined. Here we review two factors which may play a role in the pathogenesis of the disease: genetics and infection. In particular, we discuss the role of autoantibodies to LAMP-2, which may arise following infection with Gram-negative bacteria, and may contribute to the development of ANCA-associated systemic vasculitis in genetically susceptible individuals.  相似文献   
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Background

Current techniques used to obtain lung samples have significant limitations and do not provide reproducible biomarkers of inflammation. We have developed a novel technique that allows multiple sampling methods from the same area (or multiple areas) of the lung under direct bronchoscopic vision. It allows collection of mucosal lining fluid and bronchial brushing from the same site; biopsy samples may also be taken. The novel technique takes the same time as standard procedures and can be conducted safely.

Methods

Eight healthy smokers aged 40–65 years were included in this study. An absorptive filter paper was applied to the bronchial mucosa under direct vision using standard bronchoscopic techniques. Further samples were obtained from the same site using bronchial brushings. Bronchoalveolar lavage (BAL) was obtained using standard techniques. Chemokine (C-C Motif) Ligand 20 (CCL20), CCL4, CCL5, Chemokine (C-X-C Motif) Ligand 1 (CXCL1), CXCL8, CXCL9, CXCL10, CXCL11, Interleukin 1 beta (IL-1β), IL-6, Vascular endothelial growth factor (VEGF), Matrix metalloproteinase 8 (MMP-8) and MMP-9 were measured in exudate and BAL. mRNA was collected from the bronchial brushings for gene expression analysis.

Results

A greater than 10 fold concentration of all the biomarkers was detected in lung exudate in comparison to BAL. High yield of good quality RNA with RNA integrity numbers (RIN) between 7.6 and 9.3 were extracted from the bronchial brushings. The subset of genes measured were reproducible across the samples and corresponded to the inflammatory markers measured in exudate and BAL.

Conclusions

The bronchoabsorption technique as described offers the ability to sample lung fluid direct from the site of interest without the dilution effects caused by BAL. Using this method we were able to successfully measure the concentrations of biomarkers present in the lungs as well as collect high yield mRNA samples for gene expression analysis from the same site. This technique demonstrates superior sensitivity to standard BAL for the measurement of biomarkers of inflammation. It could replace BAL as the method of choice for these measurements. This method provides a systems biology approach to studying the inflammatory markers of respiratory disease progression.

Trial registration

NHS Health Research Authority (13/LO/0256).  相似文献   
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