Stimulation treatment

However, production engineers have been reluctant to use particle bridging because of the possibility of particle transport into the formation, resulting in formation damage and/or costly and often ineffective stimulation treatments. A particle bridging fluid has been developed that quickly and effectively controls fluid loss in a wide range of permeabilities and pore diameters [916]. 

For worthwhile oil or gas well stimulation, the best proppant and fluids have to be combined with a good design plan and the right equipment. The selection of a proppant is an important factor in determining how successful the stimulation treatment can be. To select the best proppant for each well, a general understanding of available proppants is imperative. 

The flowback of a proppant following fracture stimulation treatment is a major concern because of the damage to equipment and loss in well production. The mechanisms of flowback and the methods to control flowback have been recently discussed in the literature [ 1343]. To reduce proppant flow-back, a curable resin-coated proppant can be applied [1349]. The agent must be placed across the producing interval to prevent or reduce the proppant flowback. 

The stimulation treatments were performed using retarded hydrofluoric acid. A typical retarded hydrofluoric acid treatment consisted of ... 

Production was monitored for 4-6 months after the stimulation treatments. Total oil production from the twelve wells treated without the polymeric mineral fines stabilizer (1100 bbl/day) was decreasing at a rate of 0.13%/day while the produced water oil ratio remained fairly constant. The eight wells treated using the cationic organic polymer mineral fines stabilizer exhibited a total oil production of 7700 bbl/day which was increasing at a rate of... 

Ely, J.W. "Stimulation Treatment Handbook," Penwell Publications Tulsa, OK, 1985. 

Read, D.A. and Wells, G.L. "Measurement While Fracturing for Comparing and Optimizing the Performance of Well Stimulation Treatments," 1985 Proc. Annu. Southwest Pet. Short Course, 171 176. 

Jensen P. Longer term effects of stimulant treatments for attention-deficit/hyperactivity disorder. J Attention Disord 2002 6(Supplement 1) S17-S30. 

Stimulants. Treatment for narcolepsy has focused on its most disabling symptoms namely, sleep attacks and daytime drowsiness. The mainstay of treatment has... 

Gillberg C, Melander H, von Knorring AL, Janols LO, Themlnnd G Hagglof B, Eidevall-Wallin L, Gustafsson P, Kopp S. (1997) Long-term stimulant treatment of children with attention-deficit hyperactivity disorder symptoms. A randomized, donble-blind, placebo-controlled trial. Arch Gen Psychiatry 54 857-864. 

Unlabeled Uses Appetite stimulant, treatment of hormone-dependent or advanced prostate carcinoma, treatment of uterine bleeding... 

Stimulant treatment of ADHD has generated the largest body of treatment literature of any childhood psychiatric disorder. Between 1962 and 1993, over 250 reviews and over 3000 articles were published on stimulant effects (Swanson, 1993). By 1996, 161 randomized controlled trials (RCTs) had been published, encompassing 5 preschool, 150 school-age, 7 adolescent, and 9 adult studies. Improvement occurred in 65 %-75% of the children randomized to stimulants (meth-ylphenidate) [MPH] n = 133 trials dextroamphetamine [DEX] n = 22 trials pemoline [PEM] n = 6 trials) compared to 5%-30% of those assigned to pla-... 

Despite the overwhelming evidence for short-term effectiveness, only recently have studies begun to address long-term benefits of stimulant treatments. Prospective randomized controlled trials with durations of 12 to 24 months and doses up to 60 mg/day of MPH have been conducted to address this issue. The largest of these studies, the National Institute of Mental Health (NIMH)-sponsored Multimodal Treatment Study of Attention-Deficit Hyperactivity Disorder (MTA Study), showed that stimulants (either by themselves or in combination with behavioral treatments) lead to stable, long-term improvements in ADHD symptoms as long as the medication is taken (MTA Cooperative Group, 1999). 

Methylphenidate also has been combined with clon-idine, the a.2 agonist, to reduce aggression, to provide better control of ADHD symptoms after the stimulant wears off, and to counteract insomnia associated with stimulant treatment (Wilens et ah, 1994). The report of four deaths on the Federal Drug Administration (FDA) s MEDWATCH surveillance network, however,... 

There is not an empirically proven threshold of ADHD symptoms that can guide the decision about whether a particular child should be started on a stimulant, or what the initial dosage should be. Only those patients with moderate to severe impairment should be considered. Even though children diagnosed with ADD, predominantly inattentive type, might not experience impairment socially or at home, they may benefit academically from stimulant treatment. To qualify for stimulant treatment, the child must be living with a responsible adult who can administer the medication. In the case of multiple daily dosing schedules, it is necessary for school personnel to administer the mid-day dose. 

Children naive to stimulant treatment may be started directly on a sustained-release formulation. Starting doses could be any of the following 5 mg of Dexedrine spansules once in the morning, or 5 mg of Adderall bid, or 18 mg of Concerta, which is equivalent to MPH 5 mg tid. Before the availability of Concerta, it had become common practice to combine short-acting MPH with MPH-SR20 to increase efficacy and duration of effect and to allow for more flexible dosing. 

An improved understanding of the neurobiological substrates underlying attentional mechanisms, as well as the mechanisms of stimulant action, could aid in the development of future medication formulations. The lack of data on stimulant use in particular populations, especially among preschoolers and children with developmental disabilities, and questions regarding the safety and efficacy of long-term stimulant treatment underscore the need for further research. 

Angold, A., Erkanli, A., Egger, H., and Costello, J. (2000) Stimulant treatment for children a community perspective. Acad Child Adolesc Psychiatry 39 975-983. 

Greenhill, L.L. and MTA Cooperative Group. (1999) Chronic stimulant treatment effects of weight acquisition rates of ADHD children. 39 26-27. 

First, exclusive treatment with stimulant medication is effective, but may not be maximally effective for core ADHD outcomes in some children. That is, many children will experience reductions in symptoms that nevertheless continue to occur at clinically significant levels. Stated differently, while many children improve substantially with pharmacotherapy, most do not reach full normalization on symptoms with stimulant treatments alone, even at very high doses. Conversely, a greater percentage of children achieve normalization with combination treatment. 

A final limitation of stimulant treatment alone has to do with its applicability to home behavior problems. Many pharmacotherapists limit the use of stimulants to school hours during the 9 months of the academic year, to avoid growth and appetite suppression, sleep disruption, and other undesirable side effects. This leaves parents to their own devices to manage impulsive, oppositional, and disruptive behavior in the afternoons and evenings, weekends, and summers. When no other treatment is provided, parents frequently resort to coercive, hostile, and overly punitive interactions with their children, which may exacerbate rather than improve the child s behavioral problems. This is a par-... 

While stimulants are potentially abusable, recent evidence suggests that stimulant treatment substantially reduces the risk for substance abuse generated by ADHD cognitive and behavioral impairments (Bieder-man et al., 1999b). Moreover, another study has shown that the most commonly abused substance in ADHD adolescents and adults is marijuana and not stimulants (Biederman et ah, 1995b). Appropriate education and monitoring are crucial to the safe prescription of psychostimulants in adolescents and adults. 

Castellanos, F.X., Giedd, J.N., Elia, J., Marsh, W.L., Ritchie, G.F., Hamburger, S.D., and Rapoport, J.L. (1997) Controlled stimulant treatment of ADHD and comorbid Tourette s syndrome effects of stimulant and dose. / Am Acad Child Adolesc Psychiatry 36 589-96. 

Gillberg, C., Melander, H., Knotting, A., Janols, L., Thernlund, G., Gagglof, B., Wallin, L., Gustafsson, P., and Kopp, S. (1997) Longterm stimulant treatment of children with ADHD symptoms a randomized, double-blind, placebo controlled trial. Arch Gen Psychiatry 54 865-870. 

Catlson, G.A., Loney, J., Salisbury, H., Kramer, J.R., and Arthur, C. (2000h) Stimulant treatment in young hoys with symptoms suggesting childhood mania a report from a longitudinal study. J Child Adolesc Psychopharmacol 10 175—184. 

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