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21.
Melinda S. Lantz 《Current Psychosis and Therapeutics Reports》2004,2(1):7-12
Depressive symptoms in older adults are common, but the minority of elderly meet criteria for major depressive disorder. This
has led to confusion regarding the recognition of diagnosis, approach to treatment, and monitoring of outcomes in this needy
population. Few depressed older adults are willing to seek treatment from psychiatrists or mental health specialists. Treatment
approaches to the depressive spectrum of disorders in late life, which encompasses major and minor depressive disorder, dysthymic
disorder, and mood disorders related to medical conditions, must include evidence-based algorithms that can be delivered in
a variety of health care settings. Several recent multisite trials have advanced the use of collaborative care models and
the systematic stepwise approach to the treatment of depression and anxiety states in older adults. This offers the ability
to provide effective treatment of depression for older adults, consistent with current guidelines, in primary care and specialized
health care settings. 相似文献
22.
Several unique methodological challenges exist concerning the choice of the most appropriate comparator or control group for clinical research in complementary and alternative medicine (CAM). This article reviews the four major types of control groups (active control, placebo or sham, no intervention control, and different protocols of the experimental intervention), noting the different questions they answer and the different contexts in which they may be used, and discusses how this framework may be applied to CAM research in an effort to avoid methodologically flawed study designs. The choice of comparator depends on complex factors such as the research question being asked, the most plausible competing rival hypotheses, and logistical considerations related to ethics, methodology and feasibility. For example, for sham to be an effective comparator it must capture the ‘nonspecific’ elements of the treatment without containing those that are ‘specific’ to the research question at hand. However, as demonstrated by the examples of acupuncture and energy medicine, designing such sham intervention is not always easy. Controlling for social interaction between practitioners and subjects, addressing issues around ethics, having good-quality measurement of treatment integrity and intensity, and selecting practitioners of sufficient competence when doing a sham process are other important parts of correct design choices. In the light of these complexities, clinicians and researchers alike need a better match between the research questions and the design employed in order for their research to be both scientifically valid and clinically meaningful. 相似文献
23.
Jay Jegathesan Jennifer A Liebenthal Melinda G Arnett Richard L Clancy Janet D Pierce 《Medsurg nursing》2004,13(6):371-375
Advances in science have increased the knowledge of how cells die in the body (apoptosis). A basic understanding of this process can improve nurses' ability to review new scientific literature and enable them to provide safer bedside care. 相似文献
24.
Intra-lesional injections of collagenase are ineffective in the treatment of keloid and hypertrophic scars. 总被引:2,自引:0,他引:2
Norbert Kang Branavan Sivakumar Roy Sanders Charles Nduka David Gault 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(7):693-699
The treatment of keloid and hypertrophic scars remains difficult. Enzymatic digestion of keloid scars has been previously proposed as an effective treatment strategy for reducing the volume of keloid scars. To test this, we administered intra-lesional injections of pure collagenase (between 600 and 4500 units for each scar) into the keloid and hypertrophic scars of seven human volunteers (five keloid and two hypertrophic scars). Five patients (three keloid and two hypertrophic) received more than one injection of collagenase. The treatment resulted in a temporary reduction in scar volume for three of the patients with keloid scars. However, scar volumes for these three patients returned to the same (or greater) levels after 6 months of follow-up. Treatment with collagenase produced no change in scar volume for the two patients with hypertrophic scar. Side effects were numerous and severe including; pain, swelling, blistering, ulceration and ecchymosis at the site of injection. One patient required admission to hospital for 48 h after the first injection. Maximum length of follow-up was 6 months. None of the seven patients completed the study and returned for final follow-up at 2 years. This pilot study suggests that treatment of keloid and hypertrophic scars with intra-lesional injections of collagenase is ineffective. 相似文献
25.
26.
Incidence of retinal detachment following posterior chamber intraocular lens surgery 总被引:9,自引:0,他引:9
We examined the three-year incidence of retinal detachment in a consecutive cohort of 4,329 eyes which had cataract surgery with implantation of a posterior chamber intraocular lens between 1979 and 1984. The overall three-year incidence was 1.4%. The three-year incidence for open capsule cases (1.9%) was over twice that for intact capsule cases (0.8%). Axial myopes (axial length greater than or equal to 25 mm) overall were at least three times as likely to develop retinal detachment within three years (3.6%) as eyes with axial lengths less than 25 mm (1.1%). The combination of open capsule and axial myopia increased the three-year retinal detachment risk tenfold over that of the intact capsule in normal length eyes. 相似文献
27.
Retinoblastoma in Great Britain 1969-80: incidence, treatment, and survival. 总被引:7,自引:5,他引:2
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Patients with retinoblastoma diagnosed from 1969 to 1980 have been followed up for periods of up to 17 years. Data from a previous study of patients diagnosed from 1962 to 1968 have been included for analysis of incidence and second primary tumours, and for study of trends in treatment. The registration rate in Britain (which may be about 10% less than the true incidence) is about one in 23,000 live births, approximately 40% of cases being known to be genetic. There is no apparent trend in incidence during the period covered by these two studies. The three-year survival rate in 88%. Patients with bilateral tumours have a better survival rate than those with unilateral tumours for the first few years, but their long-term survival rate is worse because of later deaths from ectopic intracranial retinoblastoma or second primary neoplasms. Older children tend to have a worse prognosis, which is related to the fact that their tumours are diagnosed at a more advanced stage. There is a significantly higher survival rate for boys than for girls; this is partly accounted for by difference in age and stage at diagnosis between the sexes. Children referred to units specialising in the treatment of retinoblastoma have a higher three-year survival rate than those treated at other hospitals. Comparing methods of treatment between the periods 1962-8 and 1969-80, we find there has been a trend towards more conservative treatment. The use of chemotherapy is now usually reserved for recurrences and metastases and for palliative treatment in terminal retinoblastoma. 相似文献
28.
The growth and development of vegan children 总被引:1,自引:0,他引:1
The results of prospective study on the growth and diets, estimated from 7-day weighed food intake records, of 20 life vegan children (aged 5.8–12.8 years) are presented. The growth and development of the children were normal but they tended to be lighter in weight and exceptionally lean compared with standards. Heights were around the median of the Tanner-Whitehouse standards but were lower than the medians recently proposed by the Department of Health. Energy intakes were similar to those reported in children of the same age in the general population, but dietary fibre intakes were very high which may have influenced the digestible energy. Sugar provided an average 15.6% of the dietary energy and this was supplied mainly by fruit and fruit juice. Mean fat intakes were close to the dietary reference values. Daily intakes of essential nutrients generally met the amounts recommended, with the exceptions of calcium and vitamin B12 . Many children received supplementary sources of vitamin B12 and only two children had intakes below the lower recommended nutrient intake. Intakes of saturated fatty acids were low and those of linoleic acid were high. The ratio of linoleic/α-linolenic acid was high. As docosahexaenoic acid is absent from vegan diets, it is suggested that vegans should use oils with a lower ratio of linoleic/α-linolenic acid. Future studies should also consider the influence of a vegan diet on retinal function. None of the children was immunized against whooping cough and 11 had not been immunized against polio: 16 of the children had suffered from whooping cough. Future studies need to take into account factors other than diet when assessing the health of vegans. The results of this study show that children can be successfully reared on a vegan diet providing sufficient care is taken to avoid the known pitfalls of a bulky diet and vitamin B12 deficiency. 相似文献
29.
Increase in membrane uptake of long-chain fatty acids early during preadipocyte differentiation. 总被引:5,自引:1,他引:4
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N A Abumrad C C Forest D M Regen S Sanders 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(14):6008-6012
An increase in early rates of oleate uptake, which reflected fatty acid (FA) entry into the cells, was apparent 2-3 days after confluence of differentiating BFC-1 preadipocytes. The increase was measured in cells kept without glucose and with arsenate, where greater than 95% of intracellular radioactivity was recovered as free unesterified oleate. Uptake of retinoic acid, a molecule structurally similar to long-chain FA, remained unaltered during cell differentiation. Increase in oleate transport was related to increase in transport Vmax (determined under arsenate treatment) from 0.2 to 2 nmol/min per 10(6) cells, whereas Km remained unchanged (2 x 10(-7) M). Oleate transport was maximal at about day 6 after cell confluence (day 0), as FA metabolism (incorporation into lipids) began to gradually increase. The increase in transport preceded induction of mRNAs for both cytosolic FA-binding protein, which appeared at day 6, and for the FA synthase, which appeared at day 10. Data indicated that increases in activities of FA transport and of lipoprotein lipase, early during cell differentiation, favored increased availability of exogenous FA at a stage when endogenous FA synthesis is limited. This result would promote FA esterification and lipid deposition by supplying a rate-limiting substrate. Furthermore, oleate addition to BFC-1 preadipocytes at confluence potentiated the effect of dexamethasone in inducing mRNA for cytosolic FA-binding protein. In adipocytes, FA from exogenous or endogenous sources was necessary to maintain levels of cytosolic FA-binding protein mRNA. Thus, the increase in FA availability might contribute to, or modulate, induction of proteins necessary for preadipocyte differentiation. 相似文献
30.