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121.
Dual-energy X-ray absorptiometry (DXA)-derived appendicular lean mass/height2 (ALM/ht2) is the most commonly used estimate of muscle mass in the assessment of sarcopenia, but its predictive value for fracture is substantially attenuated by femoral neck (fn) bone mineral density (BMD). We investigated predictive value of 11 sarcopenia definitions for incident fracture, independent of fnBMD, fracture risk assessment tool (FRAX®) probability, and prior falls, using an extension of Poisson regression in US, Sweden, and Hong Kong Osteoporois Fractures in Men Study (MrOS) cohorts. Definitions tested were those of Baumgartner and Delmonico (ALM/ht2 only), Morley, the International Working Group on Sarcopenia, European Working Group on Sarcopenia in Older People (EWGSOP1 and 2), Asian Working Group on Sarcopenia, Foundation for the National Institutes of Health (FNIH) 1 and 2 (using ALM/body mass index [BMI], incorporating muscle strength and/or physical performance measures plus ALM/ht2), and Sarcopenia Definitions and Outcomes Consortium (gait speed and grip strength). Associations were adjusted for age and time since baseline and reported as hazard ratio (HR) for first incident fracture, here major osteoporotic fracture (MOF; clinical vertebral, hip, distal forearm, proximal humerus). Further analyses adjusted additionally for FRAX-MOF probability (n = 7531; calculated ± fnBMD), prior falls (y/n), or fnBMD T-score. Results were synthesized by meta-analysis. In 5660 men in USA, 2764 Sweden and 1987 Hong Kong (mean ages 73.5, 75.4, and 72.4 years, respectively), sarcopenia prevalence ranged from 0.5% to 35%. Sarcopenia status, by all definitions except those of FNIH, was associated with incident MOF (HR = 1.39 to 2.07). Associations were robust to adjustment for prior falls or FRAX probability (without fnBMD); adjustment for fnBMD T-score attenuated associations. EWGSOP2 severe sarcopenia (incorporating chair stand time, gait speed, and grip strength plus ALM) was most predictive, albeit at low prevalence, and appeared only modestly influenced by inclusion of fnBMD. In conclusion, the predictive value for fracture of sarcopenia definitions based on ALM is reduced by adjustment for fnBMD but strengthened by additional inclusion of physical performance measures. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
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Cytogenetic analysis of 114 adenocarcinomas of the lung revealed clonal abnormalities in 67 tumors. The chromosome numbers ranged from near-diploid to hypertetraploid. Clonal abnormalities seen as the sole anomaly were loss of the Y chromosome (21 tumors), trisomy 7 (2 tumors), and trisomy 12 (1 tumor). A supernumerary ring chromosome was the only clonal change in 4 tumors. The bands most often affected were 17p11-13 (13 cases), 1q10-12 and 1p22 (10 cases each), 1p11-13 and 1q21 (9 cases each), and 11p11, 11p15 and 15p11-13 (6 cases each). The chromosomes most frequently involved in structural rearrangements were chromosomes 1 (30 cases), 11 (20 cases), 3 (17 cases), 17 and 7 (16 cases each). Repeated loss of material from chromosome arms 1p, 3p, 6q, 11p, and 17p and gains of 1q were found. Recurrent structural changes were del(1)(p22) and i(5)(p10) (5 cases each) i(1)(q10), i(13)(q10), i(14)(q10) and del(17)(p11) (3 cases each). We found no abnormalities that seemed to be specifically associated with pulmonary adenocarcinomas, but isochromosomes i(1)(q10), i(5)(p10) and i(13)(q10) and changes of 6q were present in our series at frequencies higher than those generally seen in the other main types of lung cancer.  相似文献   
125.
Changes in everyday functioning and cognitive abilities are studied longitudinally in a representative sample of the oldest old. Respondents were selected by using census records from all people aged 84, 86, 88, and 90 years old living in an area of South Central Sweden, and then were assessed at 2-year intervals. The findings show high base rates for disabilities and high incidence of cognitive and functional deficits among survivors. Mortality is associated with higher rates of disability at the previous time of assessment. Because of this increased mortality rate among disabled individuals, prevalence does not rise as much as would be expected from the high incidence. Instead, new cases of disabled are partly replacing disabled individuals who died since the previous evaluation.  相似文献   
126.
Swedish guidelines for early childhood education emphasize the importance of children's existential questions. The program encourages preschool to offer children different opportunities to work on questions like what it is to be, to live and die, grow old, about religion, beliefs, traditions, etc. at their level of maturity (Social-styrelsen, 1987). Our experience in teacher education and early childhood programs is, however, that this is an area in which many teachers have difficulties. In the present empirical study 13 teachers were interviewed to find outwhat they consider existential questions for their children to be, and whatstrategies or methods they have for dealing with these questions. Teachers' conceptions about the what and how aspects of existential questions are described in terms of their qualitative differences. Each teacher was then asked to keep a diary of the existential questions children raised during the following month. Differences between the teachers' conceptions, which showed hesitation, and the spontaneous approaches and active involvement that emerged in reality, as recorded in their own diaries, are discussed.  相似文献   
127.
BACKGROUND: The pharmacokinetics of the steroid anesthetic eltanolone have been studied in male volunteers. However, steroids may exhibit gender-related differences in pharmacokinetics and surgery may alter drug disposition. METHODS: Male (n = 12) and female (n = 9) ASA 1-2 patients (age 26-45 yrs) undergoing discectomy with microsurgical technique were included. Anesthesia was induced with eltanolone 0.75 mg/kg and maintained with nitrous oxide, fentanyl and atracurium. Venous blood was sampled for up to 12 h and analyzed for eltanolone and its major metabolites. RESULTS: Induction was smooth and anesthesia uneventful, except that five cases developed a mild transient erythema. Loss of verbal contact occurred within 20-60 s. Pharmacokinetics in one person deviated significantly from the rest of the subjects. No difference between groups with respect to the primary outcome variable noncompartmental clearance (Cl, 1/min) 1.7 vs 1.6, was found. However, the volume of distribution at steady state (Vss, 1/kg) was larger in women (3.1) compared to men (1.3). The pharmacokinetics followed a three-compartment model. The half-lives (min) of the alpha, beta and gamma phases (men vs women, medians) were 1.5 vs 2.2, 42 vs 40 and 222 vs 360, respectively. Area under the curve (AUC, min microgram/l) was 39,810 vs 34,905. Context-sensitive modelling indicated that it may take 10 min more for women than men to recover from an eltanolone infusion of 2 h duration. CONCLUSION: The gender-related differences in the pharmacokinetics of eltanolone were small, and of little clinical significance for induction of anesthesia with eltanolone.  相似文献   
128.
BACKGROUND: A prospective randomized multicentre study was performed to compare the outcome of laparoscopic and open appendicectomy in patients with suspected acute appendicitis. METHODS: A total of 523 patients was randomized, but because of 23 withdrawals the outcome in 500 patients is reported, 244 in the laparoscopic group and 256 in the open group. RESULTS: Patients having laparoscopic appendicectomy recovered more quickly than those having open surgery (13 versus 21 days, P < 0.001). There was no significant difference in duration of sick leave after operation (laparoscopic group 11 days versus open group 14 days). Postoperative pain (at 24 h, 7 days and 14 days) was less after laparoscopic operations and a functional index 1 week after operation was more favourable in these patients (P < 0.001). Operating time was significantly longer in the laparoscopic group (60 versus 35 min, P < 0.01). Hospital stay and complications did not differ between the groups. Thirty laparoscopic procedures (12 per cent) were converted to open appendicectomy. CONCLUSION: Laparoscopic appendicectomy is as safe as open appendicectomy and has the advantage of allowing a quicker recovery.  相似文献   
129.
Contrast agents have dramatically improved magnetic resonance angiography (MRA) of the abdominal and peripheral arteries. The imaging technique for these applications is usually a steady-state acquisition, for which the relationship between T1 in blood and the MR signal is well known. However, in electrocardiography-triggered angiography with limited acquisition windows, this relationship is more complex. Therefore the purpose of this work is to define the relationship between the T1 in blood and the MR signal amplitude in three-dimensional magnetic resonance coronary angiography (3D-MRCA). Simulations were performed using equations describing the MR signal in both steady-state and triggered acquisition schemes. Triggered acquisition schemes use flip-angle sweeps to maintain a constant signal during the acquisition. In this study, the effect of the flip angle sweep was calculated as a function of T1. The results show that the effect of T1 shortening in contrast-enhanced 3D-MRCA differs substantially from that in conventional contrast-enhanced MRA. The triggered acquisition allows unsaturated blood to enter the volume between the acquisitions and thereby gives a much higher signal at long T1s than does steady-state acquisition. Therefore, to gain a benefit in signal amplitude with contrast agents for 3D-MRCA using gradient-echo sequences, the T1 in blood may have to be as low as 50 msec. In addition, when using a prepulse to null myocardium, the results indicate the need for a large difference in T1 between blood and myocardium to avoid signal loss in blood.  相似文献   
130.
OBJECTIVE: We aimed to describe the attitudes among GPs and physiotherapists toward the diagnostic approach and management of patients with a common shoulder disorder. METHOD: A questionnaire was sent out to 188 GPs and 71 physiotherapists. The total response rate was 71.8%. The questions were based on a written case simulation with cues about history and symptoms. RESULTS: The results showed a unanimous opinion of the diagnosis. Rotator cuff tendinitis was marked as the most probable. The two groups showed similarities in the way that they would examine the patient. The GPs referred the patients to the physiotherapists significantly more often than the other way around. The most probable choice of treatment made by the GPs was non-steroidal anti-inflammatory drugs (NSAIDs) and by the physiotherapists, movement exercises together with ergonomics. Most treatment alternatives had at least 20% of the responders marking a neutral attitude, and few treatments were disregarded. CONCLUSIONS: We conclude that in Swedish primary care GPs and physiotherapists have a uniform diagnostic approach towards patients with subacromial pain, but their choice of treatment reflects an uncertainty about the effectiveness of conservative treatments. The questioned pathogenesis of the suggested diagnosis and lack of research regarding the efficacy of conservative treatments could explain this uncertainty.  相似文献   
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