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81.
PURPOSE: There is a paucity of data describing female lower limb biomechanics during "high risk" movements linked to noncontact ACL injury. This study compared, across gender, knee kinematics associated with sidestepping maneuvers to provide insight into why women display a significantly higher incidence of this injury than do men. METHODS: Thirty participants (16 men, 14 women) had bilateral knee joint kinematic data recorded while sidestepping. A custom software package (JTMOTION) quantified maximum, minimum, and range of motion during stance for each of the three clinical knee joint rotations (flexion/extension, adduction/abduction and external/internal rotation) over 20 (leg x condition x trial (5)) trials. RESULTS: Gender differences possessed limited clinical significance with all maximum values well within safe ranges of knee motion. Women did, however, display increased intertrial variability for axial rotation patterns during cutting compared with men. This variability was thought to be unaffected by gender, with experience level found statistically (P < 0.01) to be the major determinant of knee kinematic variability during sidestepping. Hence, the level of exposure to sidestep cutting may have a large impact on the subsequent risk of ACL injury when when one performs these maneuvers. CONCLUSIONS: Gender differences in knee motions during cutting did not contribute to the increased risk of noncontact ACL injury in women compared with men. The reasons for this increased incidence, therefore, remain unclear. The potential relationship between gender and other parameters linked to ACL injury such as joint geometry, ligament morphology, and physical conditioning requires further investigation.  相似文献   
82.
The objective of the study was to compare the Euroqol EQ-5D (Euroqol) and short-form 36 (SF-36) health questionnaires in patients with chronic fatigue syndrome (CFS). One hundred and twenty-seven out-patients referred to a hospital-based infectious disease clinic with a diagnosis of CFS were contacted by post and asked to complete both questionnaires. Additional data were determined from hospital casenotes. Eighty-five patients returned correctly completed questionnaires. Euroqol health values and visual analogue scale (VAS) scores were strongly and significantly correlated with all dimensions of the SF-36, with the exception of physical limitation of role. SF-36 dimensions were in turn strongly and significantly correlated with each other, with the same exception. Patients reported a high degree of physical disability and a moderate degree of emotional or psychological ill-health. The Euroqol elements dealing with mobility and self-care referred to inappropriately severe degrees of disability for these patients with CFS. Similarly some dimensions in the SF-36 were oversensitive and did not discriminate between patients with moderate or severe disability. It was concluded that Euroqol scores correlated strongly with SF-36 scores and provided useful information about patients with CFS and that Euroqol would be a useful tool for the rapid assessment of health status in CFS. The current Euroqol instrument refers to inappropriately severe degrees of disability for patients with CFS and would need to be modified to be maximally useful in this situation.  相似文献   
83.
Suramin, a highly sulfonated drug, has been reported to be effective against several human malignancies in vitro and in vivo, and currently is undergoing clinical trials against prostate tumors. The biochemical and molecular mechanisms for suramin's antiproliferative activity are not clear. In order to define the biochemical basis for its antitumor activity and to enhance suramin's chemotherapeutic potential while decreasing its toxicity, we have examined interactions of suramin with topoisomerase I and 11 and several clinically active anticancer drugs against the human prostate (PC3 and LNCaP) cancer cell line. While etoposide, m-AMSA, camptothecin, and SN-38 (the active metabolite of CPT-11) were active in killing prostate cells as single agents, combinations of suramin and these agents were antagonistic against these cells. We found that suramin inhibited activities of purified topoisomerase I and II in vitro as measured by relaxation and cleavage assays. Further studies indicated that suramin also inhibited the drug-induced DNA damage in vitro and in isolated nuclei. These findings indicate that combinations of suramin with topoisomerase inhibitors, for example, VP-16, m-AMSA, or CPT, may not be beneficial to patients receiving suramin-containing chemotherapy. © 1993 Wiley-Liss, Inc.
  • 1 This article is a US Government work and, as such, is in the public domain in the United States of America
  • .  相似文献   
    84.
    85.
    Subclinical eye movement disorders in patients with multiple sclerosis   总被引:1,自引:0,他引:1  
    Eye movements were quantitatively evaluated in 16 patients with well-documented multiple sclerosis who had minimal or no clinically apparent eye movement disorder. Induced saccade and pursuit eye movements were recorded with electro-oculography and analyzed with newly developed programs on a laboratory digital computer. Thirteen of the 16 patients had significant (p less than 0.05) impairment of saccades and/or smooth pursuit when compared with 25 normal subjects tested in our laboratory. The type and frequency of abnormalities were as follows: saccade dysmetria, eight; delayed saccade reaction time, five; bilateral saccade slowing, four; slowing of adducting saccades only (medial longitudinal fasciculus syndrome), one; and impaired smooth pursuit, both directions, three, and one direction only, three. In addition, four patients had vestibular nystagmus with eyes closed, and one patient had typical rebound nystagmus. These data suggest that quantitative assessment of eye movements in patients with suspected multiple sclerosis can help in identifying the important "second lesion."  相似文献   
    86.
    The first commercial version of the Massachusetts General Hospital (MGH) positron camera was used to image the relative distributions of 13N (T 1/2=9.96min) in the human heart, pancreas, and liver after intravenous administration of [13N]-l-glutamate. The instrument was operated in two imaging modes. Conventional 2-dimensional (2-D) focal-plane images showed high concentrations of 13N in the heart and pancreas, and lower levels in the liver. Five PET tomographic transverse section (3-D) images were made through the heart and three through the pancreas. Our results suggest that further studies designed to gain an improved understanding of the biochemistry of [13N]-l-glutamate aided by PET imaging, especially with newer instrumentation, are worthy of further investigation.  相似文献   
    87.
    From 1985 to 1988, a state-wide program of cancer education was offered to community-based allied health professionals (AHPs) at five different program sites in Pennsylvania. During this three-year period, 512 social workers, clergy, dieticians, physical therapists and others received training to increase their knowledge about cancer and counseling, improve their supportive attitude regarding cancer patients and families, and decrease stress related to their work with this population. Overall, the Program was successful in reaching AHPs working with cancer clients who had little formal training in the cancer field. At the beginning of training, it was observed that AHPs with initially higher levels of education and more years of work experience with cancer patients had higher levels of counseling knowledge. Those who were women, worked in hospitals, or had worked with cancer patients longer exhibited higher levels of cancer knowledge. Participants who were women and who had more education had reported lower levels of job stress. Among those AHPs who completed the training courses, cancer knowledge increased by 14 percent. In addition, knowledge related to counseling cancer patients and their families improved by 11 percentage points. Perceived job stress among the AHPs also declined by 10 percent. Finally, participant supportive attitude concerning cancer clients improved.  相似文献   
    88.
    The role and operation of transport in the health sector in developing countries is important, costly but often taken for granted. This article suggests the need for a fresh look at the policy, planning and management of transport through the analysis of the essential components of a successful transport scenario for health services in developing countries i.e. transport and health planning; transport and organisational responsibility; the role of health sector donors; decision-making and procurement of transport and spares; transport and human resources; monitoring and control of transport and information; maintenance and repair; the budget. The article concludes with a checklist of key questions that may be used in assessing the contribution of transport to the health services.  相似文献   
    89.
    G R Cooper  G L Myers  S J Smith  R C Schlant 《JAMA》1992,267(12):1652-1660
    OBJECTIVE--To describe the magnitude and impact of the major biological and analytical sources of variation in serum lipid and lipoprotein levels on risk of coronary heart disease; to present a way to qualitatively estimate the total intraindividual variation; and to demonstrate how to determine the number of specimens required to estimate, with 95% confidence, the "true" underlying total cholesterol value in the serum of a patient. DATA SOURCES--Representative references on each source of variation were selected from more than 300 reviewed publications, most published within the past 5 years, to document current findings and concepts. Most articles reviewed were in English. STUDY SELECTIONS--Studies on biological sources of variation were selected using the following criteria: representative of published findings, clear statement of either significant or insignificant results, and acquisition of clinical and laboratory data under standardized conditions. Representative results for special populations such as women and children are reported when results differ from those of adult men. DATA EXTRACTION--References were selected based on acceptable experimental design and use of standardized laboratory lipid measurements. DATA SYNTHESIS--The lipid levels considered representative for a selected source of variation arose from quantitative measurements by a suitably standardized laboratory. Statistical analysis of data was examined to assure reliability. The proposed method of estimating the biological coefficient of variation must be considered to give qualitative results, because only two or three serial specimens are collected in most cases for the estimation. CONCLUSIONS--Concern has arisen about the magnitude, impact, and interpretation of preanalytical as well as analytical sources of variation on reported results of lipid measurements of an individual. Preanalytical sources of variation from behavioral, clinical, and sampling sources constitute about 60% of the total variation in a reported lipid measurement of an individual. A technique is presented to allow physicians to qualitatively estimate the intraindividual biological variation of a patient from the results of two or more specimens reported from a standardized laboratory and to determine whether additional specimens are needed to meet the National Cholesterol Education Program recommendation that the intraindividual serum total cholesterol coefficient of variation not exceed 5.0. A National Reference Method Network has been established to help solve analytical problems.  相似文献   
    90.
    Factors which regulate net hepatic glucose uptake in vivo   总被引:1,自引:0,他引:1  
    The regulation of net hepatic glucose uptake in vivo occurs by way of the hormonal milieu (insulin and glucagon), the glucose level, and the route of glucose delivery. Hyperglycemia in the absence of changes in pancreatic hormones (i.e., increased insulin and/or decreased glucagon) does not elicit significant glucose uptake by the liver. Net hepatic glucose uptake is augmented in a dose-dependent manner by a rise in insulin and is further stimulated by the presence of a "portal signal." The presence of coordinated changes in insulin, glucagon, and the glucose level in combination with the "portal signal" ensures adequate glucose uptake by the liver in response to a meal.  相似文献   
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