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991.
OBJECTIVE: To examine the physical activity (PA) counseling literature in primary care in order to identify which intervention provider has been used to date and their relative effectiveness for increasing PA. METHOD: MEDLINE and PsycINFO databases were searched for PA intervention studies in primary care settings. RESULTS: Of the 19 studies, 37% were conducted solely by physicians, 37% by allied health professionals, while 26% were combined-provider interventions. There was a decline in the number of physician-only interventions and a shift towards interventions offered by allied health professionals as adjuncts or alone. Interventions across all provider categories generated some improvements in physical activity behavior, however, it appears that allied health professionals as adjuncts or alone produced the best results in the long-term (>6 months). There was substantial variation in the location and counseling approach employed by allied health professionals. CONCLUSION: We argue for an interdisciplinary model in which physicians recommend PA and provide referrals to allied health professionals such as physical activity counselors. PRACTICE IMPLICATIONS: With physical activity counselors' specialized training and greater time available to the patient, they may provide more intensive and effective counseling required for behavior change and maintenance.  相似文献   
992.
Although cytogenetic analysis advanced the understanding of the pathogenesis of primary non-Hodgkin lymphoma and led to improved clinical management, there have been no large cytogenetic studies of post-transplant lymphoproliferative disorder (PTLD). We examined the karyotypes of 36 PTLD cases and correlated them with clinical, laboratory, and pathologic findings. The cases included 2 early lesions, 13 polymorphic PTLDs, and 21 monomorphic PTLDs (18 B-cell and 3 T-cell proliferations). Cytogenetic abnormalities were identified in 72% of monomorphic B-cell PTLDs and in all T-cell PTLDs, but in only 15% of polymorphic PTLDs and in no early lesions. The most frequent clonal abnormalities in monomorphic PTLD were trisomies 9 and/or 11 (5 cases), followed by rearrangements of 8q24.1 (4 cases), 3q27 (2 cases), and 14q32 (2 cases). MYC rearrangement (8q24.1) and T-cell-associated chromosomal abnormalities correlated with poor outcome and short survival. PTLD with trisomy 9 and/or 11 developed early after transplant, presenting as Epstein-Barr virus-positive large B-cell lymphoma with prolonged survival.  相似文献   
993.
This longitudinal study examined antecedents of substance use behavior among 176 (53% male) adolescents. Adolescents were classified as (a) abstainers (n = 19), (b) experimenters (n = 65), (c) at-risk youth (n = 63), and (d) abusers (n = 29) based on their reported substance use behavior at age 17.5. Parental behavior, peer competence, and problem behavior, measured from early childhood through age 16, were examined as predictors of substance use patterns. Multinomial logistic regression models revealed that early maternal hostility, externalizing behavior problems in first grade and at age 16, internalizing behavior in first grade and at age 16, and parental monitoring at age 16 significantly differentiated substance use groups. The study provides evidence that experiences occurring early in development, in addition to those that occur later in development, can play a pivotal role in setting the stage for late adolescent substance use behavior.  相似文献   
994.
Remodeling of injured blood vessels is dependent on smooth muscle cells and matrix metalloproteinase activity. Doxycycline is a broad spectrum matrix metalloproteinase inhibitor that is under investigation for the treatment of acute coronary syndromes and aneurysms. In the present study, we examine the mechanisms by which doxycycline inhibits smooth muscle cell responses using a series of in vitro assays that mimic critical steps in pathological vascular remodeling. Doxycycline treatment dramatically increased smooth muscle cell adhesion to the substrate, as evidenced by interference reflection microscopy and immunostaining for paxillin and phosphotyrosine. Cell aggregation was also potentiated after treatment with doxycycline. Treatment with 104 mumol/L doxycycline reduced thymidine uptake by 58% compared with untreated cells (P < 0.05) and inhibited closure of a scrape wound made in a smooth muscle cell monolayer by 20% (P < 0.05). Contraction of a three-dimensional collagen gel was used as an in vitro model for constrictive vessel remodeling, demonstrating that treatment with 416 mumol/L doxycycline for 12 hours inhibited collagen gel remodeling by 37% relative to control (P < 0.05). In conclusion, we have shown that doxycycline treatment leads to dramatically increased smooth muscle cell adhesion, which in turn might limit responses in pathological vascular remodeling.  相似文献   
995.
Fifty-two Haemophilus influenzae isolates from patients with invasive disease in the province of Manitoba, Canada, were examined for serotype, biotype, genotype, and antibiotic susceptibility. Half of the 52 isolates were found to be serotype a, and 38.5% (20 isolates) were found to be nonserotypeable (NST). There were only three serotype b strains and one each for serotypes c, d, and f. All 26 serotype a isolates belonged to biotype II and demonstrated identical or highly similar DNA fingerprints by pulsed-field gel electrophoresis. An analysis of these isolates by multilocus sequence typing showed that they belong to the clonal complex ST-23. While 69% (18 of 26) of the serotype a cases were found in males, only 9 (45%) of the 20 patients with NST isolates were males. Twenty (77%) of the 26 serotype a isolates were from patients who were 相似文献   
996.
Human bone marrow contains a population of bone marrow stromal cells (hBMSCs) capable of forming several types of mesenchymal tissues, including bone and cartilage. The present study was designed to test whether large cartilaginous and bone-like tissue constructs can be selectively engineered using the same cell population (hBMSCs), the same scaffold type (porous silk) and same hydrodynamic environment (construct settling in rotating bioreactors), by varying the medium composition (chondrogenic vs. osteogenic differentiation factors). The hBMSCs were harvested, expanded and characterized with respect to their differentiation potential and population distribution. Passage two cells were seeded on scaffolds and cultured for 5 weeks in bioreactors using osteogenic, chondrogenic or control medium. The three media yielded constructs with comparable wet weights and compressive moduli (25 kPa). Chondrogenic medium yielded constructs with higher amounts of DNA (1.5-fold) and glycosaminoglycans (GAG, 4-fold) per unit wet weight (ww) than control medium. In contrast, osteogenic medium yielded constructs with higher dry weight (1.6-fold), alkaline phosphatase (AP) activity (8-fold) and calcium content (100-fold) per unit ww than control medium. Chondrogenic medium yielded constructs that were weakly positive for GAG by contrast-enhanced MRI and alcian blue stain, whereas osteogenic medium yielded constructs that were highly mineralized by μCT and von Kossa stain. Engineered bone constructs were large (8 mm diameter × 2 mm thick disks) and resembled trabecular bone with respect to structure and mineralized tissue volume fraction (12%).  相似文献   
997.
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999.
Data from 10 sites of the NICHD/NIDCD Collaborative Programs of Excellence in Autism were combined to study the distribution of head circumference and relationship to demographic and clinical variables. Three hundred thirty-eight probands with autism-spectrum disorder (ASD) including 208 probands with autism were studied along with 147 parents, 149 siblings, and typically developing controls. ASDs were diagnosed, and head circumference and clinical variables measured in a standardized manner across all sites. All subjects with autism met ADI-R, ADOS-G, DSM-IV, and ICD-10 criteria. The results show the distribution of standardized head circumference in autism is normal in shape, and the mean, variance, and rate of macrocephaly but not microcephaly are increased. Head circumference tends to be large relative to height in autism. No site, gender, age, SES, verbal, or non-verbal IQ effects were present in the autism sample. In addition to autism itself, standardized height and average parental head circumference were the most important factors predicting head circumference in individuals with autism. Mean standardized head circumference and rates of macrocephaly were similar in probands with autism and their parents. Increased head circumference was associated with a higher (more severe) ADI-R social algorithm score. Macrocephaly is associated with delayed onset of language. Although mean head circumference and rates of macrocephaly are increased in autism, a high degree of variability is present, underscoring the complex clinical heterogeneity of the disorder. The wide distribution of head circumference in autism has major implications for genetic, neuroimaging, and other neurobiological research.  相似文献   
1000.
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