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101.

Background

Breast cancer (BC) represents one of the leading causes of cancer related deaths worldwide. New tools for diagnostic staging and therapeutic monitoring are needed to improve individualized therapies and improve clinical outcome. The analyses of circulating tumour cells may provide important prognostic information in the clinical setting.

Materials and methods

Circulating tumour cells (CTC) of 63 BC patients were isolated from peripheral blood (PB) through immunomagnetic separation. Subsequently, RT-PCR or mPCR for the genes ga733.2, muc-1, c-erbB2, mgb-1, spdef and c-erbB2 were performed. Subsequently, expression data were correlated with the tumour stages. Fourteen healthy individuals served as controls.

Results

Significant correlations with tumour stages were found in single gene analyses of ga733.2, muc-1 and in multi-gene analyses of ga733.2/muc-1/mgb1/spdef. Furthermore, a significant correlation of Ca 15-3 and all studied genes was also observed.

Conclusion

Herein, we demonstrated a positive correlation of a gene signature consisting of ga733.2, muc-1, mgb1 and spdef and advanced stages of BC. Moreover, all studied genes and gene patterns revealed a significant correlation with Ca 15-3 positive cases.  相似文献   
102.
103.

Background  

Selective serotonin reuptake inhibitors (SSRIs), a popular class of antidepressants, may increase breast cancer risk by stimulating the secretion of prolactin, a potential tumour promoter. We evaluated the effects of duration of SSRI use, cumulative dose, and latency on the risk of breast cancer by conducting a population-based case-control study utilizing Saskatchewan health databases.  相似文献   
104.
BACKGROUND: The efficacy of bed covers that are impermeable to house dust mites has been disputed. AIM: The aim of the present study was to investigate whether the combination of 'house dust mite impermeable' covers and a self-management plan, based on peak flow values and symptoms, leads to reduced use of inhaled corticosteroids (ICS) than self-management alone. DESIGN OF STUDY: Prospective, randomised, double blind, placebo-controlled trial. SETTING: Primary care in a south-eastern region of the Netherlands. METHOD: Asthma patients aged between 16 and 60 years with a house dust mite allergy requiring ICS were randomised to intervention and placebo groups. They were trained to use a self-management plan based on peak flow and symptoms. After a 3-month training period, the intervention commenced using house dust mite impermeable and placebo bed covers. The follow-up period was 2 years. Primary outcome was the use of ICS; secondary outcomes were peak expiratory flow parameters, asthma control, and symptoms. RESULTS: One hundred and twenty-six patients started the intervention with house dust mite impermeable or placebo bed covers. After 1 and 2 years, significant differences in allergen exposure were found between the intervention and control groups (P<0.001). No significant difference between the intervention and control groups was found in the dose of ICS (P = 0.08), morning peak flow (P = 0.52), peak flow variability (P = 0.36), dyspnoea (P = 0.46), wheezing (P = 0.77), or coughing (P = 0.41). There was no difference in asthma control between the intervention and control groups. CONCLUSION: House dust mite impermeable bed covers combined with self-management do not lead to reduced use of ICS compared with self-management alone.  相似文献   
105.
106.
Previous studies have shown that a significant proportion of breast cancer patients exhibit elevated G2 chromosomal radiosensitivity in contrast to controls (approximately 40%). In this study, the G2 assay was applied to a small number of Irish breast cancer patients who were recorded as sporadic cases and they were compared with a control group to compare and contrast with the previous documented studies. Lymphocyte cultures were set up on whole blood samples and stimulated with phytohaemagglutinin. The cultures were irradiated 74?h later with 0.5?Gy gamma-radiation and cells were arrested in metaphase by treating the cultures with colcemid. The chromosomes were harvested and the aberrations scored per 100 metaphases to assign a G2 score. The assay was first carried out on four donor controls to estimate intra-individual variation and then ten controls for inter-individual variation to measure assay reproducibility. The G2 assay was then applied to 27 breast cancer patients. Good intrinsic assay reproducibility was observed in the coefficient of variation (CV) data in three out of four controls. Intra-individual variation was similar in three out of four of the donors (4.6?–?5.1%) with one donor showing a higher CV compared with the others (22.9%). Inter-individual variation was calculated at 30.5% for all controls. No significant difference was observed between intra- and inter-individual variation using the variance ratio F-test. A G2 radiosensitivity cut-off of 110 aberrations/100 metaphases was calculated from the controls, and from this 70.4% of breast cancer patients and 7.7% of controls were calculated as G2 radiosensitive. This proportion of G2-sensitive breast cancer patients is the highest recorded in studies to date. It is thought that the G2 radiosensitivity assay is a biomarker of breast cancer predisposition genes of low penetrance, suggesting the presence of these genes in the Irish breast cancer patients used in this study who were recorded as sporadic cases. A larger number of Irish patients would be required to consolidate these findings and be representative of the Irish breast cancer population.  相似文献   
107.
Umbilical cord blood (UCB) provides immediate access to haemopoietic stem/progenitor cells (HSPC) but low cell number restricts use in full adult bone marrow reconstitution. This study investigated early ex vivo expansion kinetics of UCB AC133+ cells (2-4 x 10(4)/ml), mononuclear cells (MNC, 1-2 x 10(6)/ml) and AC133negative cells (AC133(neg), 2-4 x 10(4)/ml) in stroma-free 8 d liquid culture (fetal bovine serum-supplemented Iscove's-modified Dulbecco's medium (IMDM) with either 'K36EG'[c-Kit ligand, interleukin 3 (IL-3), IL-6, erythropoietin, granulocyte colony-stimulating factor] or 'TPOFL' (thrombopoietin, Flt-3 ligand). Cell enumeration, apoptosis assay and AC133/CD34/CD38 antigen immunophenotyping were performed at d 0, 3, 5 and 8. All three cell populations went through a proliferation lag phase between d 3 and d 5. AC133+ cells recovered better from lag phase with significantly higher fold increase (FI) when compared with MNC and AC133(neg) populations (K36EG FI: 15.04 +/- 5.46; TPOFL FI: 8.59 +/- 2.92, P < 0.05). After 8 d, populations lacking AC133+ cells were significantly more inclined to undergo apoptosis under proliferative conditions (P < 0.01). Also, when compared with K36EG, 8 d TPOFL-expanded AC133+ cells encompassed a significantly higher percentage of AC133+ and CD34+ early HSPC (K36EG: 20.50 +/- 2.36; TPOFL: 47.00 +/- 7.69; P < 0.05). In conclusion, TPOFL synergism demonstrated the potential for AC133+ HSPC ex vivo expansion inducing self-renewal, early HSPC maintenance and promoting cell survival status.  相似文献   
108.
BACKGROUND: Anecdotal evidence suggests that high-dose intravenous immunoglobulin (IVIG) is useful in the management of human immunodeficiency virus (HIV)-associated thrombocytopenia. STUDY DESIGN AND METHODS: To rigorously evaluate this therapy, a crossover study was designed to compare IVIG, given at 1 g per kg per day for 2 consecutive days each week for 4 weeks, with intravenous saline placebo administered according to the same schedule. Subjects were randomly assigned to receive either IVIG or saline during the first 4 weeks; if IVIG was given, there was a 4-week period of no therapy before beginning placebo administration. Criteria for eligibility were platelet count of less than 50,000 per microL (50 × 10(9)/L), elevated platelet-associated IgG levels, increased megakaryocytes in the bone marrow, and positive HIV antibody test. Twelve patients (11 men, 1 woman) were studied. Seven patients completed the full protocol. Four dropped out: after 2, 5 (2 patients), and 8 weeks that included at least 2 weeks of IVIG. RESULTS: All patients sustained an increase in platelet count in response to IVIG, with increments ranging from 15,000 to 358,000 per microL (15 to 350 × 10(9)/L) (mean, 180,000/microL [180 × 10(9)/L]; median, 174,000/microL [174 × 10(9)/L]). No patient had an increase after placebo infusions. There were no adverse effects of treatment, and weekly chemical analyses showed no new abnormalities except for mild elevations in the serum protein. The duration of responses ranged from 2 to 10 weeks. No patient demonstrated refractoriness to IVIG. CONCLUSION: IVIG consistently raises platelet counts in patients with HIV-associated thrombocytopenia.  相似文献   
109.
目的:观测研究下坡(离心)运动对大鼠骨骼肌肌浆网Ca2+-ATP酶活性,Ca2+摄取与释放在量与时程上的影响。此外,测定离子载体的刺激作用,即测定在含与不含(Ca2+离子载体)A23187时Ca2+-ATP酶活性的比值,用以评定囊泡的完整性。方法:成年雄性SD大鼠随机分为对照与离心运动组, 离心运动的大鼠分别于运动后即刻, 4, 24, 48, 72 和144h后取样 (n=7). 离心运动方式采用90min持续跑台下坡运动(-16°;15m/min)。取大鼠红股肌制备组织匀浆, 测定肌浆网Ca2+-ATP酶活性,Ca2+摄取与释放。结果:与对照组[19.25±1.38 nmol ·min-1·(mg protein)-1]相比, 肌浆网Ca2+摄取分别于运动后即刻和4h下降了29% and 36% (P<0.05), 24h依然降低(P<0.05). 肌浆网Ca2+释放与对照组[31.06±2.36 nmol·min-1·(mg protein)-1] 相比,也分别于运动后即刻和4h下降了37% and 39% (P<0.05), 24h持续降低(P<0.05). 用含离子载体测定的肌浆网Ca2+-ATP酶活性运动后4h降低了31%(P<0.05), 并于运动后24h仍然降低 (P<0.05)。运动后, 含与不含A23187时测定的Ca2+-ATP酶活性的比值未见显著性改变, 表明该运动没有明显改变肌浆网膜的完整性。结论:一次性低强度,长时间下坡运动导致肌浆网功能长时间降低, 运动后恢复期两天尚未完全恢复, 亦可构成离心运动诱导的骨骼肌某些功能降低的基础。提示这些变化可能产生于离心收缩时肌节长度不匀一性所造成的张力应激。  相似文献   
110.

Objective

The objective of this study was to determine specific provider practices associated with high provider efficiency in community emergency departments (EDs).

Methods

A mixed‐methods study design was utilized to identify key behaviors associated with efficiency. Stage 1 was a convenience sample of 16 participants (ED medical directors, nurses, advanced practice providers, and physicians) identified provider efficiency behaviors during semistructured interviews. Ninety‐nine behaviors were identified and distilled by a group of three ED clinicians into 18 themes. Stage 2 was an observational study of 35 providers was performed in four (30,000‐ to 55,000‐visit) community EDs during two 4‐hour periods and recorded in minute‐by‐minute observation logs. In Stage 3, each behavior or practice from Stage 1 was assigned a score within each observation period. Behaviors were tested for association with provider efficiency (relative value units/hour) using linear univariate generalized estimating equations with an identity link, clustered on ED site.

Results

Five ED provider practices were found to be positively associated with efficiency: average patient load, using name of team member, conversations with health care team, visits to patient rooms, and running the board. Two behaviors, “inefficiency practices,” demonstrated significant negative correlations: non–work‐related tasks and documentation on patients no longer in the ED.

Conclusions

Average patient load, running the board, conversations with team member, and using names of team members are associated with enhanced provider productivity. Identification of behaviors associated with efficiency can be utilized by medical directors, clinicians, and trainees to improve personal efficiency or counsel team members.
  相似文献   
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