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111.
E M Spencer  C C Liu  E C Si  G A Howard 《BONE》1991,12(1):21-26
The in vivo action of insulin-like growth factor-I on bone metabolism has been studied using a new model. Insulin-like growth factor-I (IGF-I) was continuously infused into the arterial supply of the right hindlimb of ambulatory rats for up to 14 days and the effects on cortical and trabecular bone formation and the number of osteoclasts were determined by histomorphometric techniques. The contralateral limb acted as an internal control. IGF-I infusion significantly increased cortical bone formation (p less than 0.01). Trabecular bone was increased 22% (p = 0.07), but the infusion was only for seven days. These effects of IGF-I were age dependent, being absent in young, rapidly growing animals, but present at least until one year of age. IGF-I appears to be a purely anabolic hormone for bone formation, since it significantly stimulates osteoblasts and decreases the number of osteoclasts. Thus, although IGF-I mediates the growth-promoting effect of growth hormone, it does not mediate growth hormone's action on bone resorption.  相似文献   
112.
Methionine synthase and neural tube defects.   总被引:3,自引:0,他引:3       下载免费PDF全文
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113.
Controlled studies of treatments effective with victims of natural disasters are almost nonexistent. This is a small study conducted under difficult conditions to test the effectiveness of Eye Movement Desensitization and Reprocessing (EMDR) in treating trauma related reactions following Hurricane Andrew. The results were positive in that EMDR produced significant improvement over wail list controls in perceived posttraumatic avoidance behaviors and thoughts as measured by changes in the Impact of Event Scale and significant improvement in subjective aversive reactions to representative experiences of the hurricane. These results suggest and support other studies that EMDR can be an effective therapeutic intervention for trauma reactions.  相似文献   
114.
This paper describes the implementation of a community-based youth violence prevention project that utilized an educational curriculum and a mass media campaign. The extent of penetration of the intervention into target areas and the degree of contamination of control areas are assessed, and the most frequently contacted forms of educational outreach are identified. Two sources of data, provider interviews and a random digit dialed telephone survey, were used to track the source and extent of teens' exposure to the intervention. Agency provider data revealed that 40% of the 92 contacted agencies actually conducted violence prevention education, reaching 22% of the target area teens. Approximately one-half of the surveyed teens reported some exposure to the program, with 13% of the teens in target areas reporting participation in interactive educational activities associated with the project. The most common source of exposure was the media campaign. Most teens report a single exposure, usually to the media campaign, although 29% report contact with more than one form of violence prevention education. While the project did not achieve community saturation, the data show that the community-based model of intervention for violence prevention is feasible and effective in reaching teenagers. This research highlights some difficulties in evaluating prevention programs, including reconciling community ownership with project identification, the ethics of curtailing services for control purposes, and factors influencing recall of participation.  相似文献   
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The Management of Health and Safety Regulations will be operative from the beginning of 1993. While duties for employers are similar to those laid out by previous legislation, Gillian Howard suggests that aspects of the new Regulations will see a new role for occupational health practitioners.  相似文献   
118.
: A rising prostate specific antigen (PSA) following treatment for adenocarcinoma of the prostate indicates eventual clinical failure, but the rate of rise can be quite different from patient to patient, as can the pattern of clinical failure. We sought to determine whether the rate of PSA rise could differentiate future local versus metastatistic failure.

: Two thousand six hundred sixty-seven PSA values from 400 patients treated with radiotherapy for localized adenocarcinoma of the prostate were analyzed with respect to PSA patterns and clinical outcome. Patients had received no hormonal therapy or prostate surgey and had ?4 PSA values post-treatment PSA rate of rise, determined by the slope of the natural log, was classified as gradual (< 0.69 log (ng/ml)/year, or doubling time (DT) > 1 year), moderate (0.69-1.4 log (ng/ml)/year, or DT 6 months-1 year), or rapid [>1.4 log (ng/ml)/year, or DT < 6 months].

: SIxty-one percent of patients had non-rising PSA following treatment; 25% of patients with rising PSA developed clinical failure, and 93% of patients with clinical failure had rising PSA. The rate of rise discerned different clinical failure patterns. Local failure occurred in 23% of patients with moderate rate of rise versus 7% with gradual rise (p = 0.0001). Metastatic disease developed in 46% of those with rapid versus 8% with moderate rise (p < 0.0001). By multivariate analysis, in addition to rate of rise, PSA nadir and rate of decline predicted local failure; those with post-treatment nadir of 1–4 ng/ml were five times more likely to experience local failure than nadir < 1 ng/ml (p = 0.0002). Rapid rate of rise was the most significant independent predictor of metastastic failure.

: The rate of PSA rise following definitive radiotherapy can predict clinical failure patterns, with a rapidly rising PSA indicating metastatic recurrence and moderately rising PSA local recurrence. This information could potentially dirent therapy; if the rise predicts metastatic failure hormonal therapy could be cosidereed, while aggressive salvage therapy may benefit subclinical local recurrence identified by a moderate rate of PSA rise.  相似文献   

119.
Partial thickness burns (PTB) usually heal within 3 weeks. Prevention of infection and desiccation of the wounds are crucial for optimal healing. Early tangential excision of the burn eschar and allografting prevent deepening of the burns, and are therefore advocated for treatment with the best functional and aesthetic results. For superficial partial thickness burns (SPTB) conservative use of topical antimicrobial agents with frequent dressing changes are implemented. We compared the conservarive treatment for PTBs and SPTBs to grafting cryopreserved cadaveric allografts with no prior excision.

Twelve patients with flame PTB areas were allografted after mechanical debridement without excision of the burn wounds. The allografts were cadaveric skin cryopreserved by programmed freezing and stored at −180°C for 30–48 months. Matching burns for depth and area were treated with silver sulfadiazine (SSD) one to two times daily until healing or debridement and grafting were required.

It was found that 80 per cent of the cryopreserved allografts adhered well and 76 per cent of the treated areas healed within 21 days, whereas only 40 per cent of the SSD-treated burns healed within 21 days.

Partial thickness burns can be treated successfully with viable human allografts (cryopreserved cadaveric skin) with no prior surgical excision. The burn wounds heal well within 3 weeks. For deep partial thickness burns (DPTB) treatment with allografts has no advantage if they have not been previously excised.  相似文献   

120.
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