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71.
BACKGROUND: Manual muscle testing has been termed a "lost art" and is often considered to be of minor value. The aim of this investigation was to study the inter-rater reliability of manual examination of the maximal voluntary strength in a sample of upper limb muscles. PATIENTS AND METHODS: The material consisted of a series of 41 consecutive patients (82 limbs) who had been referred to a clinic of occupational medicine for various reasons. Two examiners who were blinded as to patient-related information classified 14 muscles in terms of normal or reduced strength. In order to optimize the evaluation, the individual strength was assessed simultaneously on the right and left sides with the limbs in standardized positions that were specific for each muscle. Information on upper limb complaints (pain, weakness and/or numbness/tingling) collected by two other examiners resulted in 38 limbs being classified as symptomatic and 44 as asymptomatic. For each muscle the inter-rater reliability of the assessment of strength into normal or reduced was estimated by kappa-statistics. In addition, the odds ratio for the relation to symptoms of the definition in agreement of strength was calculated. RESULTS: The median kappa-value for strength in the muscles examined was 0.54 (0.25-0.72). With a median odds ratio of 4.0 (2.5-7.7), reduced strength was significantly associated with the presence of symptoms. INTERPRETATION: This study suggests that manual muscle testing in upper limb disorders has diagnostic potential.  相似文献   
72.
STUDY OBJECTIVE: To analyse gender differences in associations between physical violence and self rated health and self reported morbidity among a random sample of adults in Denmark. DESIGN AND SETTING: Two questions on self rated health and self reported morbidity respectively, were obtained from a cross sectional national health interview survey conducted among 12 028 adults (16 years +) in Denmark in 2000. A question on six different forms of physical violence was obtained from a supplementary self administered questionnaire given to the same sample. The reporting period for experienced physical violence was the past 12 months and for morbidity symptoms, the past 14 days. MAIN RESULTS: Men aged 16-24 years were significantly more likely to have experienced violence than women (OR = 3.2, 95% CI = 2.3 to 4.2). Female victims of physical violence were significantly more likely to rate their health as poor (OR = 2.02, 95% CI = 1.41 to 2.89) and to report anxiety (OR = 2.14, 95% CI = 1.35 to 3.37), depression (OR = 2.36, 95% CI = 1.55 to 3.60), and stomach ache (OR = 1.58, 95% CI = 1.01 to 2.47) than female non-victims. Male victims of physical violence were only significantly more likely to report stomach ache (OR = 1.73, 95% CI = 1.03 to 2.89) than male non-victims. CONCLUSIONS: Associations between physical violence and poor self rated health and self reported morbidity were found to be significant for women, but not for men. It is probable that gender differences in experiences of violence, as well as gender differences in health related self perception, contribute to a gender specific process of victimisation. Improved knowledge about the relation between gender specific violence and victimisation as a gender specific consequence is essential for targeting violence prevention.  相似文献   
73.
OBJECTIVE: To compare a new density gradient medium, SpermFilter, for purifying spermatozoa in assisted reproduction with the more established medium, PureSperm. DESIGN: Part 1, a multicenter study on 225 semen samples purified using either PureSperm (115 semen samples) or SpermFilter (110 semen samples). Part 2, a retrospective, single center study on a total of 898 assisted reproductive cycles (245 insemination cycles using husband semen, 58 insemination cycles using donor semen and 595 in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles. SETTING: Part 1, three fertility clinics in Denmark (two university-affiliated fertility clinics and one private clinic). Part 2, one university-affiliated fertility clinic in Denmark. MAIN OUTCOME PARAMETERS: Part 1, purity of purified spermatozoa (% motile), motility index and recovery of motile spermatozoa. Part 2, malformation and baby take-home rates (insemination cycles), fertilization, cleavage, implantation, malformation and baby take-home rates (IVF/ICSI cycles). RESULTS: No statistical differences were observed in any of the parameters investigated. CONCLUSION: SpermFilter is a valid alternative to PureSperm in assisted reproduction technology (ART).  相似文献   
74.
PURPOSE: To estimate the clinical significance of low serum concentrations of mannose-binding lectin (MBL) in patients with acute myeloid leukaemia (AML) during initial cancer chemotherapy. PATIENTS AND METHODS: 80 consecutive, newly diagnosed, and unselected AML patients (age 18-77 yr) undergoing remission induction chemotherapy. The patients were examined for 28 d. MAIN FINDINGS: Low levels of serum MBL (<1,000 microg/L) were found in 16/80 patients at diagnosis. This frequency is similar to what is found in the general population. In the remaining 64 patients, MBL concentrations were significantly higher than in controls and showed only a slight rise during the period of antineoplastic chemotherapy with its associated infectious complications. Low levels of MBL did not affect overall survival or morbidity in terms of incidence or duration of fever, or occurrence of septicaemia or pneumonia. Long-term survival was likewise independent of MBL concentration. CONCLUSION: MBL levels have no discernible influence on the occurrence or course of infections in AML patients during the initial hospitalisation. The predominant immunodeficiency during this phase is the profound granulocytopenia, which also compromises important effector functions of MBL. The finding in most AML patients of elevated MBL concentrations on admission is most likely because of the role of MBL as an acute phase reactant.  相似文献   
75.
OBJECTIVES: The objectives were to identify prognostic factors for the survival of children with cerebellar astrocytoma, and to evaluate the reproducibility and prognostic value of histological sub-classification and grading. METHODS: Children aged 0-14 years treated in Denmark for a cerebellar astrocytoma in the period 1960-1984 were included and followed until January 2001 or until their death. The histological specimens from each patient were reviewed for revised grading and classification according to three different classification schemes: the WHO, the Kernohan and the Daumas-Duport grading systems. RESULTS: The overall survival rate was 81% after a follow-up time of 15-40 years. The significant positive prognostic factors for survival were "surgically gross-total removal" of the tumour at surgery and location of the tumour in the cerebellum proper as opposed to location in the fourth ventricle. No difference in survival time was demonstrated when we compared pilocytic astrocytoma and fibrillary astrocytoma. Moreover, we found that the Kernohan and the WHO classification systems had no predictive value and that the Daumas-Duport system is unsuitable as a prognostic tool for low-grade posterior fossa astrocytomas. CONCLUSION: Discordant observations due to interobserver variability make histological sub-classification of low-grade cerebellar astrocytomas in children insufficient for predicting prognosis and biological behaviour. Similar survival rates in a population of paediatric low-grade cerebellar astrocytomas of grades I and II indicate that tumour grade has no prognostic significance within this group of patients. "Surgically gross-total removal", especially if the tumour is located in the fourth ventricle is of the highest importance for long-term survival. Histological sub-classification of the tumours has no predictive value.  相似文献   
76.
BACKGROUND: The shoulder region is a common site of work-related musculoskeletal disorders. Biomechanical models may reveal the relative importance of force, joint-moments, and angular velocity for predicting muscle activity, thereby contributing to identify risk factors. OBJECTIVE: The aim of the present study was to predict muscle activity patterns from joint kinetics during cleaning work and to identify the most important variables requesting muscle activity.Design. A comparative study of six cleaners performing five different floor cleaning tasks (combinations of tool and working method) in a laboratory setting. METHODS: Net forces and moments at the glenohumeral joint were estimated using a video-based 3D link segment model together with 3D force-transducers at each hand, separately. Angular velocities of the upper arm were calculated, and electromyographic activity was recorded bilaterally from the muscles trapezius, deltoideus, and infraspinatus. RESULTS: The biomechanical model revealed abduction moment in the glenohumeral joint to be the most important factor for development of muscle activity in m. deltoideus and m. infraspinatus, while for m. trapezius vertical force was most important. CONCLUSION: Muscle specific determinants for shoulder muscle activity could be identified from glenohumeral joint kinetics. RELEVANCE: This study documents that mechanical work requirements in terms of joint forces, moments of force and angular velocities can predict major fractions of muscle activity patterns in the upper extremities. The biomechanical model used for this prediction revealed different factors of importance for individual muscles. This knowledge is fundamental for work place interventions aiming at minimizing overloading of specific muscles to prevent or rehabilitate muscle disorders.  相似文献   
77.
Christensen FB  Laursen M  Gelineck J  Eiskjaer SP  Thomsen K  Bünger CE 《Spine》2001,26(5):538-43; discussion 543-4
STUDY DESIGN: A prospective randomized clinical study in which four observers evaluated radiographs of posterolateral fusion masses. OBJECTIVES: To evaluate the accuracy of radiograph interpretation of the posterolateral spinal fusion mass when using a detailed classification system and to analyze the influence of metallic internal fixation devices on radiologic inaccuracy. SUMMARY OF BACKGROUND DATA: In general, the literature describing the classification criteria used for radiograph interpretation of spinal posterolateral fusion has serious deficiencies. There is a need for a detailed classification system. METHODS: Seventy patients were randomly allocated to receive no instrumentation (n = 36) or Cotrel-Dubousset instrumentation (n = 34) in posterolateral lumbar fusion. All four observers participated in a prestudy discussion and evaluated the radiographs (anteroposterior, lateral) taken at the 1-year follow-up evaluation. The observers scored the radiographs twice (30 days apart). Each level on each side was judged separately. A continuous intertransverse bony bridge involving at minimum one of the two sides indicated a fusion at that level. "Fusion" indicated this quality of fusion at all intended levels. If the fusion was doubtful on both sides of the interspace, the individual case could not be classified as "fused." RESULTS: The mean interobserver agreement was 86% (Kappa 0.53), and the mean intraobserver agreement was 93% (Kappa 0.78). No difference in interobserver and intraobserver agreement was found between patients with and without supplementary pedicle screw fixation. All mean Kappa values were classified as fair or good. The four observers identified a mean fusion rate of 81%. CONCLUSION: It is extremely difficult to interpret radiographic lumbar posterolateral fusion success. Such an assessment needs to be performed by use of a detailed radiographic classification system. The classification system presented here revealed good interobserver and intraobserver agreement, both with and without instrumentation. The classification showed acceptable reliability and may be one way to improve interstudy and intrastudy correlation of radiologic outcomes after posterolateral spinal fusion. Instrumentation did not influence reproducibility but may result in slightly underestimated fusion rates.  相似文献   
78.
STUDY DESIGN: A review of the smoking habits in 426 patients who had been followed prospectively for 2 years after a lumbar spinal fusion procedure was conducted. OBJECTIVE: To analyze the effect of pre- and postoperative smoking on clinical and functional outcome after lumbar spinal fusion. SUMMARY OF BACKGROUND DATA: Several animal models have shown a negative effect of nicotine on spinal fusion. At this writing, the clinical effect of nicotine on spinal fusion has not been fully clarified. METHODS: The study comprised 426 patients who underwent lumbar spinal fusion between 1993 and 1997. These patients received a mailed questionnaire regarding their tobacco consumption before and after their surgery. All other data, including preoperative clinical and functional status, were collected prospectively during a 2-year follow-up period. To assess functional outcome, the Dallas Pain Questionnaire was used. RESULTS: The questionnaire was answered by 396 patients (93%). Of these patients, 54.5% (20% more than the background population) were smokers before the operation. Smoking of more than 10 cigarettes daily before the operation and attempted fusion at two or more levels increased the risk of nonunion: odds ratio, 2.01 (P < 0.016) and odds ratio, 3.03 (P < 0.001), respectively. Smoking cessation increased fusion rates to near those of nonsmokers. Smoking had no influence on functional outcome, as assessed by the Dallas Pain Questionnaire, but preoperative smoking predicted a negative answer to the question "Would you undergo the same treatment again, now that you know the result?" (odds ratio, 1.65; P < 0.054). CONCLUSIONS: Smoking was shown to have a negative effect on fusion and overall patient satisfaction, but no measurable influence on the functional outcome as assessed by the Dallas Pain Questionnaire.  相似文献   
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