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1.
Triple-negative breast cancer (TNBC) is defined as a type of breast cancer with lack of expression of estrogen receptor, progesterone receptor and human epidermal growth factor 2 protein. In comparison to other types of breast cancer, TNBC characterizes for its aggressive behavior, more prone to early recurrence and a disease with poor response to molecular target therapy. Although TNBC is identified in only 25%-30% of American breast cancer cases annually, these tumors continue to be a therapeutic challenge for clinicians for several reasons: Tumor heterogeneity, limited and toxic systemic therapy options, and often resistance to current standard therapy, characterized by progressive disease on treatment, residual tumor after cytotoxic chemotherapy, and early recurrence after complete surgical excision. Cell-surface targeted therapies have been successful for breast cancer in general, however there are currently no approved cell-surface targeted therapies specifically indicated for TNBC. Recently, several cell-surface targets have been identified as candidates for treatment of TNBC and associated targeted therapies are in development. The purpose of this work is to review the current clinical challenges posed by TNBC, the therapeutic approaches currently in use, and provide an overview of developing cell surface targeting approaches to improve outcomes for treatment resistant TNBC.  相似文献   
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Lasers in Medical Science - Diabetes mellitus is mostly interrelated to deficiency in wound healing. Low-level laser therapy has been shown to exert reliable effects on the acceleration of wound...  相似文献   
3.
Fluoridated toothpaste is effective for dental caries control, yet may be a risk factor for dental fluorosis. This study aimed to quantify fluoride ingestion from toothpaste by children and to investigate the effects of age, gender, and social class on the amount of fluoride ingested per toothbrushing session. Sixty‐one children, 4–6 yr of age, were recruited: 38 were from low socio‐economic (LSE) areas of Newcastle, UK, and 23 were from high socio‐economic (HSE) areas of Newcastle, UK. All expectorated saliva, rinse water (if used), and residual toothpaste were collected after brushing at home and were analysed for fluoride. Of the children, 74% and 69% from HSE and LSE areas, respectively, claimed that they brushed twice per day. The mean (SD) weight of toothpaste dispensed was 0.67 (0.36) g. The mean (SD) amount of fluoride ingested per toothbrushing session and per day was 17.0 (14.7) and 29.3 (32.8) μg kg?1 of body weight, respectively. Daily fluoride intake per kilogram of body weight did not differ significantly between children from LSE and HSE areas. Fluoride intake per toothbrushing session was significantly influenced by weight of toothpaste, its fluoride concentration, and the child's age. Whilst the average amount of toothpaste used per toothbrushing session was more than twice the recommended amount (of 0.25 g), only one child had a daily fluoride intake that exceeded the tolerable upper intake level of 0.1 mg kg?1 of body weight for this age group.  相似文献   
4.
BACKGROUND: Nosocomial infection is a serious health and financial problem. The purpose of this study was to determine the extra hospital stay attributable to nosocomial infections for patients undergoing surgery. METHOD: All patients undergoing surgery admitted from March 1, 1999, to February 28, 2000, to the 38-bed general surgery ward within a university hospital in Shiraz, Iran, were included in this study. The study was planned as a pairwise-matched case-control study nested in cohort design. A case was defined as any patient with 1 of 4 of the following nosocomial infections: urinary tract infection; surgical site infection; bloodstream infection; or pneumonia, whereby definitions for the nosocomial infections were on the basis of National Nosocomial Infection Surveillance system definitions. For each patient, an appropriate match was selected, which resulted in 69 pairs of study patients. RESULTS: The total incidence of nosocomial infection during the study period was 17.59%. The mean extra length of hospitalization as a result of all major kinds of nosocomial infections was 6.62 days total, which was obtained using 4.4, 5.33, 8.73, and 9.2 extra days for urinary tract infection, pneumonia, surgical site infection, and bloodstream infection, respectively. CONCLUSION: Nosocomial infections add considerable costs to the health care system in Iran. Therefore, the development of strategies and concepts to reduce the incidence of nosocomial infections is cost-effective and warranted, and an appropriate surveillance system on the basis of international criteria is the cornerstone for this task.  相似文献   
5.
Objective: To identify the incidence rate, relative risk, hotspot regions and incidence trend of COVID-19 in Qom province, northwest part of Iran in the first stage of the pandemic.Methods: The study included 1125 officially reported PCR-confirmed cases of COVID-19 from 20 February 2020 to 20 April 2020 in 90 regions in Qom city, Iran. The Bayesian hierarchical spatial model was used to model the relative risk of COVID-19 in Qom city, and the segmented regression model was used to estimate the trend of COVID-19 incidence rate. The Poisson distribution was applied for the observed number of COVID-19, and independent Gamma prior was used for inference on log-relative risk parameters of the model. Results: The total incidence rate of COVID-19 was estimated at 89.5 per 100000 persons in Qom city (95% CI: 84.3, 95.1). According to the results of the Bayesian hierarchical spatial model and posterior probabilities, 43.33% of the regions in Qom city have relative risk greater than 1; however, only 11.11% of them were significantly greater than 1. Based on Geographic Information Systems (GIS) spatial analysis, 10 spatial clusters were detected as active and emerging hotspot areas in the south and central parts of the city. The downward trend was estimated 10 days after the reporting of the first case (February 7, 2020); however, the incidence rate was decreased by an average of 4.24% per day (95% CI: ?10.7, ?3.5). Conclusions: Spatial clusters with high incidence rates of COVID-19 in Qom city were in the south and central regions due to the high population density. The GIS could depict the spatial hotspot clusters of COVID-19 for timely surveillance and decision-making as a way to contain the disease.  相似文献   
6.
Various studies have described glycyrrhizin (GL), an active triterpenoic saponin extract of licorice roots, as an anti-inflammatory, antiviral, antimicrobial, anti-tumor and immunomodulating agent. The activity of GL has been mainly attributed to its metabolites, 18-alpha (GA) and 18-beta-glycyrrhetinic acid (GB), which their mechanism of action on the immune system cells is not clearly known. In this study, we have investigated the effects of GA and GB on the immune system by targeting dendritic cells and analyzing phenotypic and functional maturity of murine dendritic cells (DCs) after treatment with these components. Stimulation of DCs with GA and GB resulted in up-regulation of CD40, CD86 and MHC-II molecules indicating their effects on the maturation of DCs. These components induced the allogenic immunostimulatory capacity of DCs by stimulating the proliferation of T cells and production of the T helper (h)1-promoting cytokine, IL-12. They also increased the production of IFN-γ by T cells in mixed-lymphocyte reaction. In conclusion, these results indicate that GA and GB may insert their immunomodulatory effects by enhancing DC maturation and modulating Th1/Th2 response through an increase in Th1 responses, implying their beneficial in host defense against infectious diseases.  相似文献   
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Due to adolescents’ future crucial roles, their health needs should be included in the national health system policy. In this cross-sectional study 2010 female adolescents were recruited from randomly selected schools in Iran. To obtain their health needs, the participants completed a self-administrated questionnaire. It was revealed that emotional needs were the most important health needs of adolescents. Furthermore, there was a meaningful relationship between health needs’ score with the adolescents’ age and their mothers’ education level. Finally, the mean score of health needs was significantly higher in urban adolescents. Therefore, it is suggested that adolescents’ emotional health needs to be paid attention; otherwise irrecoverable serious problems may occur in the next generation’s health.  相似文献   
10.

Background

Colitis, a colonic inflammatory condition, showed a linkage with hepatobiliary disorders such as cirrhosis. It has been reported that both endogenous opioids and nitric oxide (NO) play critical roles in colitis pathogenesis. Moreover, opioid and NO levels showed elevation in patients with cirrhosis. The aim of this study was to evaluate the effect of cirrhosis on the experimental model of colitis and the possible involvement of opioidergic/nitrergic systems in rats.

Methods

Colitis was induced by acetic acid 28 days after bile duct ligation (BDL). L-NAME, as an inhibitor of NO synthase and naltrexone, as an antagonist of opioid receptors were administered intraperitoneally to animals during 3 days after induction of colitis. Macroscopic colitis lesion area, inflammatory mediators change, NO metabolite levels, and colon microscopic injuries were assessed 3 days after induction.

Results

Cirrhosis significantly reduced the severity of damages to the colon. Administration of L-NAME (10 mg/kg), naltrexone (10 mg/kg) and co-administration of L-NAME (1 mg/kg) and naltrexone (5 mg/kg) significantly decreased the protective effect of BDL on colitis. Nitrite elevated levels in BDL rats were significantly diminished in L-NAME- and naltrexone-treated animals. Histopathology parameters and cytokines level alterations in the colon of acetic acid-treated animals after BDL was reversed after injection of L-NAME, naltrexone, and co-administration of L-NAME (1 mg/kg) + naltrexone (5 mg/kg).

Conclusion

Cirrhosis improved the intestinal damages induced by acetic acid in rats which may be mediated through interaction of nitrergic and opioidergic systems.  相似文献   
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