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排序方式: 共有8788条查询结果,搜索用时 31 毫秒
91.
David Litaker Randall D Cebul Sophia Masters Thomas Nosek Robert Haynie C Kent Smith 《Academic medicine》2004,79(7):690-697
PURPOSE: It is unclear whether academic health centers are successfully addressing societal needs and expectations by preparing students with knowledge and skills in disease prevention and health promotion. The authors assessed whether students were exposed to key content in these areas and whether they felt this exposure was adequate. METHOD: All components of the first three years of the Case Western Reserve University (Case) curriculum were examined in 2001 to create a curricular map, using competencies in disease prevention and health promotion identified by the Association of Teachers of Preventive Medicine (ATPM) as a template to assess the scope of instruction. Case students' United States Medical Licensing Examination (USMLE) Step 2 subscores in preventive medicine and health maintenance from 1994 to 2000 and graduating seniors' assessment of the adequacy of their training were compared to national data from the Association of American Medical Colleges' 2000 Graduation Questionnaire (GQ). RESULTS: Most content areas identified by ATPM were present in the Case curriculum and were offered frequently in a variety of educational venues over the first three years. USMLE scores increased nationally and at Case from 1994 to 2000 and Case students' perception of training adequacy in preventive medicine and health promotion was comparable to national ratings from the 2000 GQ. CONCLUSIONS: Broad and frequent exposure to disease prevention and health promotion core competencies has value, but may not sufficiently prepare students to deliver health-promoting services confidently. Creative curricula highlighting prevention's relevance throughout clinical practice and incorporating formal opportunities to apply knowledge and build experience may result in greater success. 相似文献
92.
In chicks infected with Mycoplasma synoviae after hatching agglutinins were not detected for between 27 and 42 days. By this age the largely asymptomatic infection had spread extensively by contact. Detection of maternal agglutinins from hatching to 9 days in chicks from infected hens indicated that this should be considered as a diagnostic technique particularly where access to parent stock is limited. 相似文献
93.
We performed a randomized doubled-blind study to evaluate whether there was a benefit in delay in tourniquet deflation with intra-articular administration of morphine and bupivacaine following operative arthroscopic surgery. In 34 patients the tourniquet was deflated immediately and in 38 patients the tourniquet remained inflated for 10 min following injection. The analgesic efficacy was assessed using pain scores and the amount of supplementary analgesia required. The results demonstrate no benefit in delay in tourniquet deflation. 相似文献
94.
95.
Changes in Lower Leg Anterior Compartment Pressure Before,During, and After Creatine Supplementation
Potteiger JA Carper MJ Randall JC Magee LJ Jacobsen DJ Hulver MW 《Journal of Athletic Training》2002,37(2):157-163
OBJECTIVE: To determine if 35 days of creatine supplementation (Cr) followed by 28 days of no supplementation altered lower leg anterior compartment pressure (ACP) at rest and after exercise. DESIGN AND SETTING: Subjects were divided into 2 treatment groups: (1) high dose (0.3 g Cr.kg body mass(-1).d(-1) for 7 days followed by 0.03 g Cr.kg body mass(-1).d(-1) for 28 days), or (2) low dose (0.03 g Cr.kg body mass(-1).d(-1) for 35 days). After 35 days, supplementation was terminated, and no Cr was ingested for 28 days. SUBJECTS: Sixteen physically active, healthy, college-aged males (O(2)max = 47.6 +/- 5.1 mL.kg(-1).min(-1)). MEASUREMENTS: At baseline, 7 days and 35 days of supplementation, and 28 days postsupplementation, ACP was measured preexercise and immediately, 1, 5, 10, and 15 minutes postexercise after a treadmill run at 80% O(2)max. RESULTS: For ACP, there was no significant group-by-time interaction, but there was a significant time effect for group when the data were combined. ACP was significantly increased at preexercise, immediately postexercise, and 1, 5, and 10 minutes from baseline to 7 days. ACP remained significantly elevated from baseline at 35 days immediately postexercise and 1 minute postexercise. After 28 days of no supplementation, ACP began to return to presupplementation levels, with only the 1-minute postexercise measurement significantly elevated from baseline. CONCLUSIONS: Creatine supplementation increased ACP at rest and after exercise, and ACP began to return to normal after 28 days of no supplementation. 相似文献
96.
A series of experiments were conducted on instrumental modification of the Galvanic Skin Response (GSR) in a discrimination procedure where preparatory signals indicated which discriminative stimulus was to occur. When shock avoidance was contingent upon the presence of a response the GSR was enhanced; when shock avoidance was contingent upon the inhibition of a response there was a decrement in reactivity. Heart rate acceleration occurred to Respond stimuli while deceleration occurred to Inhibit stimuli. Various types of cognitive strategies were reported by the subjects from attempts to control attention by attending less to stimuli associated with inhibition to attempts to arouse a response by thinking of exciting events and to inhibit by thinking of calming events. Postexperimental recognition of words tended to be negatively related to magnitude of response. When the verbal stimuli served directly as discriminative stimuli, however, these relationships tended to be reversed. 相似文献
97.
Battaglia TC Clark RT Chhabra A Gaschen V Hunziker EB Mikic B 《Connective tissue research》2003,44(5):218-224
The mechanisms by which tendon strength is established during growth and development and restored following injury are not completely understood and are likely to be complex, multifactorial processes. Several studies examining the relationship between mechanical behavior and ultrastructural characteristics of tendons and ligaments during growth and maturation suggest that collagen fibril diameter is strongly correlated with tendon strength. Because of the similarities between development and repair processes of musculoskeletal tissues, increases in tendon strength during healing may be related to increases in fibril ultrastructural parameters such as fibril size, numerical density, and area fraction. In this study, we compared murine Achilles tendons at various time points after tenotomy with sham-operated controls in tensile tests to failure and examined tendons using electron microscopy to assess collagen fibril ultrastructure. We found that in the 6-week period following Achilles tenotomy, fibril mean diameter remained significantly smaller than sham-side diameter by a factor of 2-3. Despite the persistently small fibril size, increasing numerical density resulted in a gradual increase in fibril area fraction. Biomechanical strength did not reach that of intact tendons until some time between 5 and 7 weeks, approximately the same time period when fibril area fraction began to approach sham values. These data suggest that parameters other than collagen fibril size are most responsible for increased tendon strength during healing. 相似文献
98.
Vladimir Turzhitsky Yang Liu Nahla Hasabou Michael Goldberg Hemant K. Roy Vadim Backman Randall Brand 《Disease markers》2008,25(6):313-321
Pancreatic cancer screening has been hampered by the high rate of complications associated with interrogating the pancreas. The closest non-invasively accessible mucosa available for pancreatic cancer screening is the periampullary duodenal tissue. Our earlier report has shown the potential of using optical markers to interrogate this tissue for the presence of pancreatic cancer. In this study, we report a larger data set of low-coherence enhanced backscattering (LEBS) and elastic light scattering fingerprinting (ELF) optical markers from the periampullary duodenal mucosa. Optical measurements from biopsy samples were acquired from a total of 203 patients with varying clinical classification including healthy controls, a family history of pancreatic cancer, pancreatitis, mucinous cystic precursor lesions, pancreatic cancer, and other pancreatic malignancies. Evaluation of the performance of an independent testing set for discriminating healthy control patients from pancreatic cancer patients showed a 95% sensitivity, 71% specificity, and 85% area under the receiver operator characteristic (AUROC) curve. Importantly, this performance was uncompromised for detecting potentially curable stages of the disease. Additionally, optical markers in higher risk populations such as family history and pancreatitis had values between those of healthy control and pancreatic cancer patients, thus allowing for future investigations of screening from these high risk groups. 相似文献
99.
OBJECTIVE: To examine college athletic trainers' confidence in helping female athletes who have eating disorders. DESIGN AND SETTING: We mailed a 4-page, 53-item survey to head certified athletic trainers at all National Collegiate Athletic Association Division IA and IAA institutions (N = 236). A 2- wave mailing design was used to increase response rate. SUBJECTS: A total of 171 athletic trainers returned completed surveys for a response rate of 77%. Eleven institutions either did not identify their head athletic trainer or did not have an identifiable mailing address. Two surveys were undeliverable because of incorrect mailing addresses. MEASUREMENTS: The survey consisted of 4 subscales: (1) efficacy expectation, (2) outcome expectation, (3) outcome value, and (4) experience in dealing with eating disorders. Content validity was established by review from a national panel of experts. Reliability ranged from.66 to.73 for the subscales. RESULTS: Although virtually all athletic trainers (91%) had dealt with a female athlete with an eating disorder, only 1 in 4 (27%) felt confident identifying a female athlete with an eating disorder, and only 1 in 3 (38%) felt confident asking an athlete if she had an eating disorder. One in 4 athletic trainers (25%) worked at an institution that did not have a policy on handling eating disorders. Almost all athletic trainers (93%) felt that increased attention needs to be paid to preventing eating disorders among collegiate female athletes. CONCLUSIONS: Collegiate athletic programs are encouraged to develop and implement eating-disorder policies. Continuing education on the prevention of eating disorders among athletes is also strongly recommended. 相似文献
100.
We investigated the role of saccadic gaze fixations in encoding target locations for planning a future manual task consisting of a sequence of discrete target-oriented actions. We hypothesized that fixations of the individual targets are necessary for accurate encoding of target locations and that there is a transfer of sequence information from visual encoding to manual recall. Subjects viewed four targets presented at random positions on a screen. After various delays following target extinction, the subjects marked the remembered target locations on the screen with the tip of a hand-held stick. When the targets were presented simultaneously among distracting elements, the overall accuracy of marking increased with presentation time and total number of targets fixated because the subjects had to serially fixate the individual targets to locate them. Without distractors, the marking accuracy was similarly high regardless of duration of target presentation (0.25-8 s) and number of targets fixated; it was comparable to that with distractors when all four targets had been fixated. This indicates parallel encoding of target locations largely based on peripheral vision. Location memory was stable in these tasks over the delay periods investigated (0.5-8 s). With parallel encoding there was a "shrinkage" in the visuomotor transformation, i.e., the distances between the markings were systematically smaller than the corresponding inter-target distances. When the targets were presented sequentially without distractors, marking accuracy improved with the total number of targets fixated and shrinkage in the visuomotor transformation occurred only with parallel encoding, i.e., when subjects did not fixate the targets. In all experimental conditions for trials in which targets were fixated during encoding, there was little correspondence between the marking sequence and the sequence in which the targets were fixated. We conclude that subjects benefit from fixating targets for subsequent target-oriented manual actions when the targets are presented among distractors and when presented sequentially; when distinct targets are presented simultaneously against a blank background, they are efficiently encoded in parallel largely by peripheral vision. 相似文献