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21.
The effects of three increasingly intensive training methods on therapist use, knowledge, and implementation adherence of contingency management (CM) with substance abusing adolescents were evaluated. Ten public sector substance abuse or mental health provider organizations were randomized to one of three training conditions: workshop and resources (WS +), WS + and computer assisted training (WS +/CAT), or WS +/CAT and supervisory support (WS +/CAT/SS). Across conditions, 161 therapists participated in the training experiences, and measures were obtained at baseline and 2-month intervals for 12 months following workshop participation. Across training conditions, therapists reported increased CM use, knowledge, and implementation adherence through the 12-month follow-up. The findings show that community-based practitioners are amenable to the adoption of evidence-based treatments when provided access to useful resources. Moreover, high quality workshops in combination with resource access can increase knowledge of the evidence-based treatment and might enhance intervention adherence to a level needed to improve youth outcomes.  相似文献   
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A significant number of people in the North Central Province of Sri Lanka suffer from chronic kidney diseases (CKD), and the author revisits existing literature related to CKD to find its causative factor. There is a direct connection between high fluoride levels in drinking water and kidney disease, and there are unhealthy levels of fluoride in the groundwater in Sri Lanka’s CKD-affected areas. Based on the following observations, the author believes with confidence that excess fluoride in drinking water and in the locally grown food in the affected areas are the culprits of CKD in Sri Lanka.
  • Fluoride excretion rate is considerably lower in children than adults, leading to renal damage of children living in areas with high fluoride.
  • Adults who had renal damage due to fluoride in childhood are vulnerable to CKD with continued consumption of water from the same source.
  • Patients with chronic renal insufficiency are at an increased risk of chronic fluoride toxicity.
  • High content of fluoride in groundwater paves the way to excess fluoride in local food crops, consequently adding more fluoride to the systems of the consumers.
  • People who work outdoors for prolonged periods consume excess water and tea, and are subjected to additional doses of fluoride in their system.
  • In the mid-1980s, the increase in water table levels of the affected areas due to new irrigation projects paved the way to adding more fluorides to their system through drinking water and locally grown foods.
  相似文献   
24.
BackgroundPostural orthostatic tachycardia syndrome (POTS) is a complex, multifaceted disorder that impairs functional status and quality of life. Current pharmacological treatments are limited.ObjectivesThis study investigated the effect of ivabradine (selective blocker of the Ifunny channel in the sinoatrial node) on heart rate, quality of life (QOL), and plasma norepinephrine (NE) levels in patients with hyperadrenergic POTS defined by plasma NE >600 pg/ml and abnormal tilt table test.MethodsIn total, 22 patients with hyperadrenergic POTS as the predominant subtype completed a randomized, double-blinded, placebo-controlled, crossover trial with ivabradine. Patients were randomized to start either ivabradine or placebo for 1 month, and then were crossed over to the other treatment for 1 month. Heart rate, QOL, and plasma NE levels were measured at baseline and at the end of each treatment month.ResultsThe average age was 33.9 ± 11.7 years, 95.5% were women (n = 21), and 86.4% were White (n = 23). There was a significant reduction in heart rate between placebo and ivabradine (p < 0.001). Patients reported significant improvements in QOL with RAND 36-Item Health Survey 1.0 for physical functioning (p = 0.008) and social functioning (p = 0.021). There was a strong trend in reduction of NE levels upon standing with ivabradine (p = 0.056). Patients did not experience any significant side-effects, such as bradycardia or hypotension, with ivabradine.ConclusionIvabradine is safe and effective in significantly improving heart rate and QOL in patients with hyperadrenergic POTS as the predominant subtype.  相似文献   
25.
Life Table analysis of stomal complications following colostomy   总被引:22,自引:10,他引:22  
PURPOSE: This study was designed to evaluate the longterm complication rate of left iliac fossa end sigmoid colostomies and to determine etiologic factors. METH-ODS: A retrospective chart review and actuarial analysis were performed. RESULTS: The crude and actuarial risks of paracolostomy complications in 203 patients were 51.2 percent and 58.1 percent at 13 years, respectively. Paracolostomy hernia was the most common complication (36.7 percent at 10 years). Siting the stoma through the belly of the rectus abdominis muscle did not reduce the risk of hernia, but an extraperitoneal course had a significantly lower risk of herniation when compared with a transperitoneal course and intestinal obstruction was marginally less frequent. Paracolostomy hernias were otherwise more likely in the elderly, and in those with other abdominal wall hernias. Mesenteric fixation did not reduce the subsequent chance of prolapse. The reduction in the risk of intestinal obstruction when lateral space closure was employed was not statistically significant (4 percent vs. 10 percent,P < 0.1), and all three patients with stomal retraction had had lateral space closure. CONCLUSION: The evidence in this study that spans a 22-year period questions much surgical technical dogma and raises the possibility that parastomal hernias may, like inguinal hernias, represent a failure in the transversalis fascia that might technically be avoidable.  相似文献   
26.
目的 探讨不明原因晕厥患者在直立倾斜试验中血流动力学反应模式及构成比例,方法 190例不明原因晕厥患者在安静环境下空腹进行直立倾斜试验。持续监测心电和血压,观察其血压、心率变化,结果 190例不明原因晕厥患者在直立倾斜试验中,经典血管迷走反应者106例(55.8%),其中混合型12例(6.3%),心脏抑制型4例(2.1%),血管减压型90例(47.4%),正常直立反应者56例(29.4%),自主神经障碍型10例(5.3%),体位性心动过速型4例(2.1%),心脏变时功能障碍型8例(4.2%),直立性低血压者6例(3.2%)。结论 不明原因晕厥患者在真诚立倾斜试验中以经典血管迷走反应为主,但还存在其他4种异常的血流动力学变化。  相似文献   
27.
28.
Sympathetic Activation in Neurocardiogenic Syncope. Introduction : Tilt table testing is widely used in the management of patients with neurocardiogenic syncope. However, the exact pathophysiologic mechanism of this disorder is still under debate. Likewise, therapy of these patients continues to represent a challenge in many cases. Therefore, the present study aimed to gain further insight into the pathophysiology of this syndrome and to examine easily accessible clinical parameters that can improve therapy selection.
Methods and Results : In 16 patients with neurocardiogenic syncope, changes in endogenous catecholamine concentrations were determined during repeated tilt table testing before and during treatment with metoprolol. Tachycardia preceded syncope in 8 of 10 responders compared to only 1 of 6 nonresponders (P < 0.05). In responders, the relative increase in epinephrine levels averaged 197%± 51% during drug-free tilting and 75%± 33% during repeated testing while on β-blocker therapy (P < 0.05). In nonresponders, there was a smaller relative increase in epinephrine averaging 137%± 35% at baseline tilt. During repeated tilt testing, a similar increase was observed in these patients with recurrent syncope (156%± 104%; P = NS compared to baseline).
Conclusion : In patients with neurocardiogenic syncope who show both an increase in epinephrine concentration during tilt test and sinus tachycardia prior to the onset of symptoms, β-blocker treatment is very effective. These findings confirm the major role of sympathetic activation as a trigger of syncope. Particularly, heart rate changes at the onset of syncope may allow early identification of patients responding to antiadrenergic therapy.  相似文献   
29.
目的探讨临床护理路径表在消化内镜治疗患者护理过程中的应用效果。方法将2012年5—12月行高难度消化内镜治疗患者分为观察组和对照组各250例,观察组按制订的护理路径表实施护理,对照组采用常规的护理方法。结果观察组患者平均住院日、平均住院费用、并发症发生率显著低于对照组,差异有统计学意义(P0.05);观察组患者内镜知识掌握率、对护理工作满意度、医生对护士满意度显著高于对照组,差异有统计学意义(P0.05)。结论对消化内镜治疗患者应用路径进行护理,可有效减少患者住院费用、缩短住院日、减少并发症、提高患者对护理工作的满意度及内镜知识的掌握率,提高医生对护士的满意度。  相似文献   
30.
A major goal in ecology is to understand mechanisms that increase invasion success of exotic species. A recent hypothesis implicates altered species interactions resulting from ungulate herbivore overabundance as a key cause of exotic plant domination. To test this hypothesis, we maintained an experimental demography deer exclusion study for 6 y in a forest where the native ungulate Odocoileus virginianus (white-tailed deer) is overabundant and Alliaria petiolata (garlic mustard) is aggressively invading. Because population growth is multiplicative across time, we introduce metrics that correctly integrate experimental effects across treatment years, the cumulative population growth rate, λc, and its geometric mean, λper-year, the time-averaged annual population growth rate. We determined λc and λper-year of the invader and of a common native, Trillium erectum. Our results conclusively demonstrate that deer are required for the success of Alliaria; its projected population trajectory shifted from explosive growth in the presence of deer (λper-year = 1.33) to decline toward extinction where deer are excluded (λper-year = 0.88). In contrast, Trillium’s λper-year was suppressed in the presence of deer relative to deer exclusion (λper-year = 1.04 vs. 1.20, respectively). Retrospective sensitivity analyses revealed that the largest negative effect of deer exclusion on Alliaria came from rosette transitions, whereas the largest positive effect on Trillium came from reproductive transitions. Deer exclusion lowered Alliaria density while increasing Trillium density. Our results provide definitive experimental support that interactions with overabundant ungulates enhance demographic success of invaders and depress natives’ success, with broad implications for biodiversity and ecosystem function worldwide.Steadily increasing pressure by invasive plant species on native biodiversity (1) disrupts both community and ecosystem function (2) and results in staggering economic costs worldwide (3, 4). A major goal in ecology is to understand how changes over time in species interactions affect invasion success of exotic species (58). According to ecological theory, the ability of the resident community to limit the success of invading exotics [biotic resistance (9, 10)] will depend upon ecological context that includes the suite of local interactors (1115). The abundance of herbivores and their local impacts (11, 14, 16) can play a prominent role in how fast plant populations grow or shrink and how much the relative abundance of plant species changes over time (5, 15), including changes associated with plant invasions (11, 1619). Recently, increased browsing pressure by overabundant ungulate herbivores on native plant communities has been proposed as a fundamental cause of a shift from native to exotic plant domination in forests and rangelands worldwide (11, 16, 20). Wild and domesticated ungulates (e.g., deer, elk, goats, sheep, horses, cows) that are either native or introduced have all been implicated in this process (11, 16, 20).Overabundant ungulates may change the success of invading exotics in numerous ways. Ungulate browsing on natives may depress their abundance and ability to compete (2124) and increase abiotic resources available to invaders (11, 25, 26), which can act synergistically to decrease communities’ ability to resist invasion (biotic resistance; refs. 8 and 10). Ungulates disperse exotic seeds (27, 28) and create novel abiotic conditions with respect to soil disturbance, soil quality, and light availability (21, 22, 26), which may enhance exotic establishment and growth. Moreover, although ungulates are considered diet generalists, in fact, they frequently behave as selective foragers (2124, 29), preferring natives to exotics. In this circumstance, unpalatable invaders can have a double advantage over natives—both release from historic enemies (20) and inedible to new potential enemies in the invaded range (30, 31). Together, these mechanisms not only implicate overabundant ungulates in their direct impact on the rate at which populations of palatable native species grow or shrink, but point to their potentially pivotal role in reducing the biotic resistance of the native community to favor invaders (13, 14).To determine how ungulate herbivores affect the fitness of invaders and natives, field experiments that manipulate herbivore access for several years and are spatially well replicated are required (11, 32, 33). The multiyear, population-level demographic data gained in such experiments can be used to estimate the ultimate metric of fitness: population growth rate (λ). However, despite the widespread use of manipulative experiments that alter herbivore access to plants, we still lack appropriate demographic data (i.e., complete schedules of fertility, mortality and growth for all stages) in invaded systems (2, 14, 17, 32, 33). Instead, herbivore–plant invader experiments typically report simple metrics of plant success (e.g., percent cover or counts of individuals) at a single time point. For example, the metric “percent cover” estimates the total leaf area of a species, often relative to other species. Lower leaf area of native plants where ungulates have access could merely be the result of leaf tissue lost to herbivory, with no actual change in invader or native numbers. Likewise, “snapshot counts” of invaders often leave out critical life cycle stages and do not provide information on rates of survival, reproduction, or growth, without which population dynamics cannot be analyzed. Thus, it is not surprising that ungulate exclusion experiments that apply such metrics provide no unified answer regarding exotic invaders [effect on invasion success: none (3436); mixed (37, 38); positive (3941; reviewed in ref. 16)] because these studies cannot address population viability of invaders or natives. Also, although evidence of ungulates’ influence on native plant population dynamics from exclusion experiments has been previously demonstrated (e.g., refs. 42 and 43), our study is distinct. We know of no other such experiments testing the link between ungulates and invasive exotic population growth rate in invaded systems.Here, we use experimental demography and stage-based data (rates of survival, fertility, and growth) collected over multiple years to test the hypothesis that an overabundant native ungulate herbivore drives positive population growth of invaders (11, 16). We emphasize that in herbivore removal experiments the fitness of plant populations, which is measured by population growth rate, is predicted to rebound with persistent, multiplicative beneficial effects over time. What has not previously been recognized in such experiments is that treatment effects accumulate over the span of an experiment (44), necessitating a quantitative metric that integrates fitness over the entire life cycle and over time. Moreover, population growth is a process that is multiplicative across time. Thus, we introduce the use of cumulative population growth rate, λc, at the end of a multiyear experiment as the metric that correctly integrates experimental effects across the observed sequence of demographic changes across time. Our multiyear demographic projection and the corresponding multiyear retrospective sensitivity analysis provide fresh insights. To facilitate comparisons of our results with studies that estimate λ from single-year transitions, we present λper-year, the geometric mean of λc. Our retrospective sensitivity analyses [similar to life table response experiment analysis for periodic matrices (45, 46)] of λc reveal how each part of the life cycle contributes to overall differences in cumulative population dynamics caused by an experimental manipulation. We conclusively show that overabundant deer create conditions favorable for explosive exponential population growth of an exotic plant invader, but that when deer are excluded, populations of the invader are projected to decline exponentially.We focus on the native ungulate Odocoileus virginianus (white-tailed deer; hereafter, deer) and the exotic herbaceous understory invader Alliaria petiolata (Brassicaceae; garlic mustard; hereafter, Alliaria), which both present serious management concerns in North American forests. Relative to historical records, deer densities are currently 4–10 times higher than pre-European settlement densities across North America (47). Overabundant native deer in forests exert the same kinds of pressures as other ungulates (native and nonnative, wild and domesticated) globally, including perturbation of understory communities (22, 27, 39), exotic seed dispersal (27), and alteration of abiotic conditions (21, 39). Likewise, Alliaria ranks among the most problematic forest invaders in North America (48). Introduced by early colonists, it was naturalized on Long Island, New York, by 1868 (reviewed in ref. 48). In its native Eurasia, Alliaria grows in edge or disturbed habitats, whereas in North America it increasingly occupies forest interiors (48). Relative to the slow-growing, long-lived understory community it invades, Alliaria has a rapid, biennial life cycle: spring seedlings form overwintering rosettes by autumn. In their second year, plants reproduce, disperse seeds, and die. In its invaded range, Alliaria has high population growth rates (λ = 1.4–3.4) (48), which project annual increases in numbers of 40–240%. Alliaria’s invasive success has been hypothesized to result from various factors. These include the following: novel allelopathic weapons, enemy release, positive soil feedback, taxonomic novelty, high competitive ability, and specific phenotypic traits. No single factor has yet to explain the broad reach of this tenacious exotic (reviewed in ref. 48). Here, we investigate what has not been previously explored: the role of ungulate disruption of native community biotic resistance (13) on Alliaria’s invasion success. To date, deer and Alliaria have been foci of intense, largely separate, research efforts. Our approach uses experimental demography to jointly examine these two issues. Together, they constitute an ideal system to investigate ungulate–exotic plant invasion linkages (11, 16).Our experiment was conducted in a beech–maple forest in southwestern Pennsylvania (Trillium Trail Nature Reserve, Allegheny County, Pennsylvania: 40° 52′ 01.40″ N; 79° 90″ 10.75″ W). Winter aerial flyovers of this area performed between 1993–2004 revealed overabundant deer: currently 20–42 deer per km2 compared with an historic density of 10–12 deer per km2 (Fig. S1). In a different area in this same forest, Knight et al. (39) used an indirect metric of plant performance and found that relative percent cover of Alliaria was lower and that there was significantly less bare ground where deer were excluded relative to sites where deer were present (39). However, in that study Alliaria nevertheless remained abundant (the second most abundant species) even where deer were excluded. That study (39), which used relative percent cover as a response metric, left several questions unanswered, including the following: Was Alliaria’s relative decline due to the native species increasing in cover with no actual change in cover of the invader? Did the tenacious invader’s population growth rate actually decline? Given these unanswered questions from the earlier study, the Trillium Trail forest was an ideal location to address these questions and to conduct a definitive demographic experiment that could distinguish among these mechanisms. In 2002, we established paired plots (n = 6 pairs of 14 × 14-m plots) with one plot per pair randomly assigned to a fenced treatment that excluded deer (see Materials and Methods for details). The other plot in each pair remained unfenced and experienced ambient levels of deer and other animals. We compared population-level responses of native understory herbaceous perennial species and Alliaria between treatments for 6 y. For three focal native herbs that are palatable to deer (e.g., ref. 49) and the unpalatable Alliaria, we quantified reproductive success each year. For Alliaria and one of the natives, Trillium erectum (Melanthiaceae, hereafter Trillium), we additionally quantified the complete schedule of survival, fertility, and growth rates each year. We selected Trillium as a counterpoint to Alliaria as it is the most common flowering herbaceous species found at Trillium Trail Nature Reserve. Moreover, Trillium species are a preferred food source for deer (49) and well-known phytoindicators of deer browse (e.g., ref. 49; but see ref. 50). In a nonexperimental study, deer browse levels within a population were negatively correlated with population growth rate for another species in the genus, Trillium grandiflorum (51). Accordingly, Trillium represents a model for understanding the impact of deer on native species, and the loss of such browse-sensitive species can be a metric of decline in forest integrity (52). We predicted that, if ungulates disrupt the native community and enhance exotic invasion success, then in plots experimentally protected from deer: (i) native species would have higher reproductive success, (ii) Trillium fitness would increase and its density would increase, (iii) Alliaria fitness would decrease and its density would decline. Meanwhile, in plots where deer were allowed access, we expected either the opposite trends or no change from initial conditions. Alternatively, if any of the other previously hypothesized mechanisms for Alliaria’s success (e.g., novel weapons, enemy release) are at play and more important than herbivore impacts, then we would expect Alliaria’s population growth rate to remain high despite deer exclusion, while predictions for the effects of deer on the natives remain the same.In brief, from 2003 to 2008 at annual censuses, we scored reproduction and survival of individuals of Alliaria and of the three native perennials that are preferred food sources for deer (49): Trillium, Maianthemum racemosum (Ruscaceae), and Polygonatum biflorum (Ruscaceae). In plots accessible to deer, we also scored deer browse. To assess the effect of deer exclusion on the fitness of Trillium and Alliaria, we implemented our multiyear matrix projection analysis to calculate cumulative population growth rates from 2003 to 2007 for each treatment. To construct matrices, we defined five life cycle stages for the perennial Trillium (germinant bank, seedling, one-leafed juvenile, three-leafed nonflowering, and three-leafed flowering; Fig. S2A) and three life cycle stages for Alliaria (dormant seed in the seed bank, rosette, and fruiting adult; Fig. S3A). Matrix elements were calculated as a function of the vital rates associated with each stage transition (Figs. S2A and S3A). We captured cumulative effects of deer exclusion or continued deer overabundance over time, parameterizing multiyear projection matrix models B, for each species and treatment by multiplication of annual projection matrices AYEAR-TREATMENT (e.g., BDEER = A2006-DEER A2005-DEER A2004-DEER A2003-DEER). The matrix B, at the heart our analyses, contains the rates at which individuals that were at a given stage at the beginning of the experiment will have either become or produced individuals of each stage after four transition years. Our analyses of multiyear matrices provide integrative measures of plant fitness over the time frame of the experiment, including treatment-specific cumulative population growth rates (λc, the dominant eigenvalue of B), time-averaged λ’s (λper-year-TREATMENT = the fourth root of the dominant eigenvalue, λc, of B), and an overall measure of the effect of protecting plants from deer on plant fitness Δλper-year = λper-year-NO_DEER – λper-year-DEER. [Note: Pooled plot data (Trillium) and individual plot data (Alliaria) were used. See Materials and Methods, Matrix Construction for Each Species and Treatment.] Finally, to uncover mechanistic differences between the response of the native and the exotic to deer exclusion, we use a life table response experiment retrospective sensitivity analysis (45, 46). The analysis shows how important each of these 4-y demographic rates is to differences in λc between treatments, quantified by contributions made during transitions from stage j to stage i, cij.  相似文献   
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