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131.
Background: Only limited data exist comparing differences in sensory function and responses to neural blockade in infant and adult rats. Therefore, the authors sought (1) to compare baseline thermal, proprioceptive, and postural responses in infant, adolescent, and adult rats; and (2) to compare the effects of sciatic nerve blockade on thermal, proprioceptive, and postural responses in infant, adolescent, and adult rats.

Methods: Infant, adolescent, and adult rats were evaluated for proprioceptive, thermal, and mechanical nociceptive and motor function before and after sciatic blockade using a detailed neurologic examination.

Results: Mechanical and thermal nociception were present in all rats, starting from age 1 day. The withdrawal reflex latency to pinch was rapid at all ages, whereas that reaction to thermal stimulus depended on both age and temperature. In contrast, the tactile placing response and hopping response were absent at birth and developed completely during the first 10 days of life. The extensor postural thrust was absent in the first 2 weeks of life and developed variably during the first 50 days of life. Sciatic blockade duration is shorter in infant rats than in adult rats receiving the same dose per kilogram. A brief halothane general anesthetic at the time of sciatic injection in infant or adult rats does not alter the duration of blockade.  相似文献   

132.
Little is known about oral health care behaviors of community-dwelling, cognitively impaired elderly (CIE) persons. Few studies have been conducted regarding the actual provision of oral care for CIE persons or the attitudes and concerns about oral health among their caregivers. The CIE person's ability to perform self-care decreases over time, and the role of the caregiver in daily oral care becomes increasingly important. The purpose of this pilot study was to explore the attitudes toward oral health and identify related concerns among caregivers who care for community-dwelling CIE persons. Caregivers were surveyed by means of a self-administered, mailed questionnaire. To maintain confidentiality, an intermediary was used for recruitment and data collection. Overall, 148 caregivers were invited by an intermediary to participate in the survey; only 21 (14%) consented to participate and returned the questionnaire. This paper discusses some of the numerous methodological challenges identified when an attempt was made to survey caregivers' attitudes toward and barriers to providing oral care for a dependent CIE.  相似文献   
133.
134.
Objective: Our purpose was to determine whether insulin-like growth factors I and II preferentially stimulate uterine leiomyoma cells versus myometrial cells in monolayer culture.Study design: Leiomyomas and normal myometrium were obtained at hysterectomy from five premenopausal women. Specimens were enzymatically digested for use in primary monolayer cell cultures. By use of serum-free media, insulin-like growth factor I or II was added in 1, 10, and 100 ng/ml concentrations to both cell types with the patient serving as her own control. Cell number, prolactin production, and proliferative index values were measured on day 15 of cell culture.Results: Significant increases in cell number were found in the leiomyoma cultures (p < 0.05) treated with 10 and 100 ng/ml insulin-like growth factors I but not with insulin-like growth factos II. Neither factor exerted a stimulatory effect on myometrial cells.Conclusion: Insulin-like growth factor sI preferentially stimulates leiomyoma cells in monolayer culture. These results suggest an autocrine-paracine role in vivo for this factor in conjuction with gonadal steroids in promoting leiomyoma growth.  相似文献   
135.
A brief overview is provided of the bioactivity of macrolides against a range of bacterial species. Topics considered include the cellular pharmacokinetics of uptake and efflux of these drugs and the importance of intra- or extracellular and cytoplasmic or granular location on their activity. Emphasis is placed on the importance of synergy between macrolides and host defenses, with drug accumulation producing modification of cellular function, such as enhancement of phagocytosis, and exocytosis of polymorphonuclear neutrophils. Such interaction may explain the activity of such agents against organisms which normally inhibit fusion of phagolysosomes.  相似文献   
136.
137.
There have been few reports of relative rates of provision of dental health services in rural and urban settings, a comparative measure of access to care in these populations. One part of a statewide survey of active North Carolina general dentists (n=959, response rate=47%) was designed to quantify provision of prosthetic services. To determine contrasting rural and urban rates, responses were analyzed according to dentists'self-report of practice city size using analysis of covariance with percent of insured patients in the practice as the covariate. Mean per-patient-visit rates for crowns, fixed partial dentures, removable partial dentures, and extractions, as well as the distributions of treatment following tooth extraction, differed by city size, with practitioners in the smallest cities reporting treatment distributions reflecting more frequent loss of teeth and less frequent replacement. These differences in patterns of prosthetic care echo the limited existing information describing oral health status, provider supply, and receipt of care, all of which suggest that differential levels of access to care exist and lead to differences in oral health outcomes.  相似文献   
138.
139.
An extrachromosomal nucleic acid element was detected in high-molecular-weight DNA preparations formBabesia equi merozoites. This extrachromosomal element was shown to be DNA rather than RNA and had an apparent fragment size of about 9 kilobasepairs (kb). Hybridization experiments using purified 9-kb DNA as a probe revealed sequence homologies with extrachromosomal DNA from two otherBabesia species.  相似文献   
140.
The aim of this study was to test the inter-rater reliability of a revised oral assessment guide (ROAG) for patients residing in a geriatric rehabilitation ward. A consecutive sample of 140 patients was recruited for the study. Oral assessments were performed for 133 newly admitted patients by one registered nurse (RN) during a period of six months. A dental hygienist (DH) carried out 103 oral assessments during the same half-year. For 66 patients, the RN and the DH performed independent assessments. There was an agreement between the RN and the DH in the majority of the independent assessments, except for tongue and teeth/dentures. The percentage agreement exceeded 80 percent. Inter-rater agreement measured by Cohen's Kappa coefficient ranged from moderate to very good and percentage agreement had a range of 58 to 91 percent. The agreement was highest in assessment of voice and swallowing (91%). Assessments of teeth and dentures seemed to be most difficult for the RN to evaluate. ROAG was found to be a clinically useful assessment tool. Additional education and training is needed to improve the reliability of the oral assessments and should include continuous support from a dental hygienist as well as a pictorial manual on how to use the ROAG.  相似文献   
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