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Human embryonic stem cells: A potential source for cellular therapy   总被引:4,自引:0,他引:4  
Many degenerative human diseases reflect damage to cells that are not normally repaired or replaced, such as diabetes, Parkinson's disease, hepatic failure and congestive heart failure. Preliminary studies in animals and humans have suggested that these diseases may be treatable by transplantation of healthy cells. Such cells may be obtained by in vitro culture of embryonic stem cells, which are capable of differentiating into many cell types. This review discusses applicative approaches for the derivation, maintenance and safety of human embryonic stem (hES) cells as well as ethical concerns surrounding their possible source for cellular therapy. hES cells offer broad application in cellular therapy; however, this review specifically emphasizes on cardiovascular repair, generation and characterization of hES cell-derived cardiomyocytes, vascular progenitors and differentiation of derivatives.  相似文献   
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A randomized, placebo-controlled, double-blind study involving 60 subjects, aged 6-18 years old, was conducted over a period of 3 months to determine the effect of Pycnogenol® (a proprietary mixture of water-soluble bioflavonoids extracted from French maritime pine) on mild-to-moderate asthma. After baseline evaluation, subjects were randomized into two groups to receive either Pycnogenol® or placebo. Subjects were instructed to record their peak expiratory flow with an Assess® Peak Flow Meter each evening. At the same time, symptoms, daily use of rescue inhalers (albuterol), and any changes in oral medications were also recorded. Urine samples were obtained from the subjects at the end of the run-in period, and at 1-, 2-, and 3-month visits. Urinary leukotriene C4/D4/E4 was measured by an enzyme immunoassay. Compared with subjects taking placebo, the group who took Pycnogenol® had significantly more improvement in pulmonary functions and asthma symptoms. The Pycnogenol® group was able to reduce or discontinue their use of rescue inhalers more often than the placebo group. There was also a significant reduction of urinary leukotrienes in the Pycnogenol® group. The results of this study demonstrate the efficacy of Pycnogenol® as an adjunct in the management of mild-to-moderate childhood asthma.  相似文献   
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OBJECTIVE: To assess readability of over-the-counter (OTC) contraceptive product instructions currently available, compare the results with previous studies from a decade ago, and review the implications for health care providers, in particular pharmacists counseling on OTC contraceptives. METHODS: A sample of contraceptive instructions was submitted to a readability analysis using four standard readability formulas. Products included condoms, spermicides, and emergency contraception instruction pamphlets. RESULTS: Reading grade levels for condoms ranged from 6th to 12th grade. The average reading levels for the spermicides were 9th-10th grade and for the emergency contraceptives 10th-12th grade. These results were consistent with those of similar studies performed a decade ago. CONCLUSIONS: Consumers need to have at least a high school reading level in order to comprehend current product instructions. Very little has changed in the past decade regarding readability of OTC contraceptive patient instructions, despite calls to simplify written instructions. Healthcare providers, in particular pharmacists, must be aware of these disparities to enhance patient education and advocate for simpler reading materials.  相似文献   
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Poverty influences health status, life expectancy, health behaviours, and use of health services. This study examined factors influencing the use of health-related services by people living in poverty. In the first phase, 199 impoverished users of health-related services in 2 large Canadian cities were interviewed by their peers. In the second phase, group interviews with people living in poverty (n = 52) were conducted. Data were analyzed using thematic content analysis. Diverse health-related services were used to meet basic and health needs, to maintain human contact, and to cope with life's challenges. Use of services depended on proximity, affordability, convenience, information, and providers' attitudes and behaviours. Use was impeded by inequities based on income status. To promote the health of people living in poverty, nurses and other health professionals can enhance the accessibility and quality of services, improve their interactions with people living in poverty, provide information about available programs, offer coordinated community-based services, collaborate with other sectors, and advocate for more equitable services and policies.  相似文献   
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Gonadal steroid levels were determined in the ovary ofSalamandra salamandra infraimmaculataduring the reproductive cycle in populations from a xeric region in northern Israel. Varying proportions of previtellogenic and vitellogenic oocytes were present throughout the year, and mature oocytes were present in winter and spring. The numbers of mature oocytes were greater between December and April, after parturition. The levels of 17β-estradiol and testosterone rose during oocyte vitellogenesis and maturation. Levels of progesterone and 17α-hydroxy progesterone appeared to be related to the level of vitellogenesis. Gravid females contained greater quantities of all four steroids than did nongravid females.  相似文献   
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