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81.
It is unknown whether treatment for osteoporosis with raloxifene is safe or effective in those with chronic kidney disease (CKD). With data from a multicenter, randomized, placebo-controlled trial of 7705 postmenopausal women with osteoporosis, the effect of raloxifene on rate of change of bone mineral density (BMD), incidence of fractures, and adverse events by stage of CKD was examined over 3 yr. Baseline serum creatinine values were available for 7316 women, and these values were used to assign a category of creatinine clearance (CrCl) using the Cockcroft-Gault formula (CrCl < 45, 45 to 59, and > or = 60 ml/min). BMD was measured at baseline and annually by dual x-ray absorptiometry. Within the placebo group, lower baseline CrCl was associated with a trend for higher annual losses of BMD at the femoral neck; however, within the raloxifene group, lower baseline CrCl was associated with greater increases in femoral neck BMD. This interaction between category of CrCl and treatment assignment was significant for rate of change of BMD at the hip. Irrespective of kidney function, raloxifene treatment was associated with a greater increase in spine BMD, a reduction in vertebral fractures, and no effect on nonvertebral fractures compared with placebo. Within each category of kidney function, adverse events were similar between the raloxifene and placebo groups. In conclusion, raloxifene increases BMD at both the hip and the spine and reduces the risk for vertebral fractures among individuals with CKD. The effect ofraloxifene on hip BMD is greater among those with mild to moderate CKD.  相似文献   
82.
Objective: To examine the outcomes of geriatric ESRD patients selected for kidney transplantation. Design: Data were extracted from the USRDS Standard Analysis Files (SAF). All persons ages 75 and over who received a kidney transplant from 1994 to 2000 were compared with those remaining on dialysis or on a transplant waiting list. Data on mortality or removal from the waiting list were obtained from the United Network for Organ Sharing (UNOS). The main outcome measure was patient and kidney transplant survival. Results: Superior five year survival after kidney transplantation was attained by the geriatric cohort given a live donor transplant (59.9%), compared with recipients of deceased donor kidneys (40.3%), dialysis patients waiting for transplant (29.7%), and those who were not selected for kidney transplantation and remained on dialysis (12.5%). The likelihood of being removed from the waiting list for any reason was higher in this group (over 75) (30.3%) than in the 66–75 age group (26.8%). Their average annual mortality rate on the waiting list was 7.9, compared to 6.6% for those 66–75. Conclusion: Even after the age of 75 years, kidney transplantation provides substantial life prolongation and excellent graft survival. USRDS Disclaimer: The data reported here have been supplied by the United States Renal Data System (USRDS) and the United Network for Organ Sharing (UNOS). The interpretation and reporting of these data are the responsibility of the authors and in no way should be seen as official policy or interpretation of the US government.  相似文献   
83.
To examine the degree of trauma in major osteoporotic fractures (MOF) in men versus women, we used data from 15,698 adults aged ≥65 years enrolled in the Osteoporotic Fractures in Men (MrOS) study (5994 men) and the Study of Osteoporotic Fractures (SOF) (9704 women). Participants were contacted tri‐annually to ascertain incident fractures, which were confirmed by radiographic reports and coded according to degree of self‐reported trauma. Trauma was classified as low (fall from ≤ standing height; fall on stairs, steps, or curb; minimal trauma other than fall [coughing, turning over]); moderate (collisions with objects during normal activity without associated fall); or high (fall from > standing height; severe trauma [motor vehicle accident, assault]). MOF included hip, clinical vertebral, wrist, and humerus fractures. Mean fracture follow‐up was 9.1 years in SOF and 8.7 years in MrOS. A total of 14.6% of the MOF in men versus 6.3% of the MOF in women were classified as high trauma (p < 0.001); men versus women more often experienced fractures resulting from severe trauma as well as from fall > standing height. High‐trauma fractures were more significantly common in men versus women at the hip (p = 0.002) and wrist (p < 0.001) but not at the spine or humerus. Among participants with MOF, the odds ratio of a fracture related to high‐trauma fracture among men versus women was 3.12 (95% confidence interval [CI] 1.70–5.71) after adjustment for traditional risk factors. Findings were similar in analyses limited to participants with hip fractures (odds ratio [OR] = 3.34, 95% CI 1.04–10.67) and those with wrist fracture (OR = 5.68, 95% CI 2.03–15.85). Among community‐dwelling older adults, MOF are more likely to be related to high trauma in men than in women. These findings are not explained by sex differences in conventional risk factors and may reflect a greater propensity among men to engage in risky behavior. © 2015 American Society for Bone and Mineral Research.  相似文献   
84.
The purpose of this study was to compare the VO2 kinetic and mechanical power responses of boys and men to all out 90 s sprint cycle exercise. Eight boys (14.6 ± 0.3 y) and eight men (33.8 ± 6.5 y) volunteered to participate and completed a ramp test (to determine VO2peak and ventilatory threshold, VT) and then on subsequent days, two 90 s all out cycle sprints on an isokinetic cycle ergometer. During each test, breath-by-breath pulmonary gas exchange and power output were measured. Parameters from the power output profiles were derived from the average response of the two tests including peak power (PP, highest power output in 1 s), end power (EP60-90, power over the last 30 s), and mean power over the 90 s (MP90). Independent pairwise and dependent t-tests were used to compare the data from tests between adults and boys subject groups. Significant differences between adults and boys were found for absolute PP (881.4 ± 60.7 vs 533.6 ± 50.7 W), EP60-90 (288.6 ± 25.7 vs 134.3 ± 17.6 W) and MP90 (434.5 ± 27.4 vs 238.4 ± 17.3 W, p =0.001) respectively. Relative to body mass significant differences between adults and boys were found for EP60-90, MP90 and total work (p < 0.002). The boys attained 90 s VO2 values that were closer to VO2peak than their adult counterparts (93.3 ± 2.6 vs 84.9 ± 2.3 %, p = 0.03). They also demonstrated faster VO2 kinetics (10.8 ± 1.5 vs 17.6 ± 1.0 s, p < 0.01). In conclusion, during all out 90 s cycle sprinting boys were able to attain VO2 values that were closer to VO2peak and a faster time constant than adult men. These findings provide insight into the contribution and speed of response of the aerobic system during an ‘anaerobic’ test.

Key Points

  • The results of this study confirm the significant contributions of the aerobic energy systems during so called ‘anaerobic tests’.
  • Boys were able to attain VO2 values from an all out 90 s sprint cycle that were closer to their aerobic VO2 peak test than adults. More detailed studies are required to investigate the limiting factors that prevent VO2 peak being reached in an all out sprint cycle.
  • All out tests of a duration > 30 s and coupled with gas and power analyses offer paediatric physiologists considerable scope to examine the contributions of the anaerobic and aerobic energy systems until more ethically viable methods are found.
Key Words: VO2peak, anaerobic, kinetics, aerobic, ergometry  相似文献   
85.
A Method of Separating Agglutinated and Free Erythrocytes   总被引:2,自引:0,他引:2  
A method is described for separating two populations of erythrocytes of different blood groups by agglutinating one population with a suitable antiserum and separating the agglutinates from the free cells by centrifugation through a layer of 20% dextrose.

Résumé


Une méthode est décrite pour la séparation de deux populations érythrocytaires de types sanguins différents en agglutinant une population avec un anti-sérum correspondent et en séparant les agglutinats des cellules libres par centrifugation dans un substrat constitué par une solution de dextrose à 20%.

Zusammenfassung


Es wird eine Méthode zur Trennung von zwei Erythrozytenpopulationen mit unterschiedlicher Blutgruppe beschrieben. Sie beruht darauf, daß die eine Population mittels eines geeigneten Antiserums agglutiniert und durch Zentrifugation durch eine Schicht von 20%iger Dextrose von den freien Zellen abgetrennt wird.  相似文献   
86.
Background: Polysensitization ( ≥ 3 contact allergies) may be regarded as a special entity in patients with contact allergies. However, this group of polysensitized patients is poorly characterized. Filaggrin mutations are associated with atopic eczema and lead to impaired skin barrier which may predispose to contact allergy. Therefore, it is of interest to consider atopic eczema and contact allergies, especially in patients with multiple allergies.
Objective: To characterize polysensitized patients regarding occurrence, duration and course of dermatitis, and examine potential risk factors for polysensitization, including atopic eczema.
Methods: A questionnaire case–control study of 562 polysensitized and 1124 single/double-sensitized individuals was performed.
Results: The results show that 45% of polysensitized and 31% of single/double-sensitized patients had or had had atopic eczema, and atopic eczema was identified as a risk factor for polysensitization. Patients with leg ulcer constituted only a minor part of the polysensitized group and leg ulcers were not identified as a risk factor for polysensitization in this study. The influence of contact allergies on duration and course of disease diverged between the group of patients with atopic eczema and the group without atopic eczema.
Conclusion: Patients with atopic eczema were overrepresented in the group of polysensitized patients and polysensitized patients should be viewed in the light of occurrence or lack of atopic eczema.  相似文献   
87.
Background: Hand eczema as well as nickel contact allergy is prevalent among hairdressers. Recently, two female hairdressers were diagnosed with nickel contact allergy-related hand eczema following prolonged skin contact with scissors and crochet hooks used during work.
Objectives: To determine the proportion of hairdressers' scissors and crochet hooks that released an excessive amount of nickel and to determine the prevalence of nickel allergy among patch-tested female hairdressers.
Materials: Random hairdressers' stores in Copenhagen were visited. The dimethylglyoxime (DMG) test was used to assess excessive nickel release. The prevalence of nickel allergy among female hairdressers from the database at Gentofte Hospital was compared with the prevalence of nickel allergy among other consecutively patch-tested dermatitis patients.
Results: DMG testing showed that 1 (0.5%; 95% CI = 0 − 2.0) of 200 pairs of scissors and 7 (53.8%; 95% CI = 26.0 − 82.0) of 13 crochet hooks released an excessive amount of nickel. The prevalence of nickel allergy was higher among middle-aged and older female hairdressers than among young female hairdressers.
Conclusions: The prevalence of nickel allergy was lower among young hairdressers in comparison to older hairdressers. This may possibly be a result of the European Union (EU) Nickel Directive or a consequence of a decreased use of nickel-releasing work tools in salons. When nickel allergic hairdressers present with hand eczema, their work tools should be investigated for nickel release.  相似文献   
88.
Background: An association between nickel contact allergy and hand eczema has previously been demonstrated. In 1990, Denmark regulated the extent of nickel release in the ear‐piercing process as well as nickel release from consumer products. Objectives: This study aimed to evaluate the effect of the Danish nickel regulation by comparing the prevalence of concomitant nickel allergy and hand eczema observed in two repeated cross‐sectional studies performed in the same general population in Copenhagen. Materials: In 1990 and 2006, 3881 18–69 year olds completed a postal questionnaire and were patch tested with nickel. Data were analysed by logistic regression analyses and associations were expressed as odds ratios (ORs) with 95% confidence intervals (CIs). Results: The prevalence of concomitant nickel contact allergy and a history of hand eczema decreased among 18–35‐year‐old women from 9.0% in 1990 to 2.1% in 2006 (P < 0.01). The association between nickel contact allergy and a history of hand eczema decreased in this age group between 1990 (OR = 3.63; CI = 1.33–9.96) and 2006 (OR = 0.65; CI = 0.29–1.46). Among older women, no significant changes were observed in the association between nickel contact allergy and hand eczema. Conclusions: Regulatory control of nickel exposure may have reduced the effect of nickel on hand eczema in the young female population.  相似文献   
89.
The preservative methyldibromo glutaronitrile (MDBGN) has caused an epidemic of contact allergy in Europe. However, most data concerning contact allergy comes from hospital departments of dermatology. As a part of the primary health care sector, Danish dermatologists in private practice provide the front line of care for patients with skin diseases. Data from this source may therefore better reflect trends in the general population than material from hospital departments of dermatology. In this study, the frequency of MDBGN allergy and the characteristics of patients seen by dermatologists in private practice were studied. In 1 year, 2146 patients were patch tested by the participating dermatologists from 4 clinics in various parts of Denmark. 5% (110) had positive patch tests to MDBGN, with no difference between the sexes. After adjustment was made for other background variables, multivariate analysis using logistic regression showed a significant association between hand eczema and MDBGN allergy (OR 2.5, P < 0.001). In 53 cases (52.4%), the patch test reaction to MDBGN was judged to be of current relevance. Creams and lotions accounted for 31% of the identified causative products and liquid soaps for 23%. It is concluded that contact allergy to MDBGN is frequent among patients seen by dermatologists in private practice. This is consistent with results from hospital departments of dermatology in Europe and indicates a general trend and ongoing epidemic in the general population. The significant relationship between hand eczema and MDBGN allergy is of concern, and the finding that wash-off products, especially liquid soaps, play a significant role in MDBGN allergy calls for a revision of the safety assessment of MDBGN in wash-off products.  相似文献   
90.
Axillary dermatitis is common and overrepresented in people with contact allergy to fragrances. Many people suspect their deodorants to be the incriminating products. In order to investigate the significance of isoeugenol in deodorants for the development of axillary dermatitis when used by people with and without contact allergy to isoeugenol, patch tests with deodorants and ethanol solutions with isoeugenol, as well as repeated open application tests (ROAT) with roll-on deodorants with and without isoeugenol at various concentrations, were performed in 35 dermatitis patients, 10 without and 25 with contact allergy to isoeugenol. A positive ROAT was observed only in patients hypersensitive to isoeugenol (P<0.001) and only in the axilla to which the deodorants containing isoeugenol had been applied (P<0.001). Deodorants containing isoeugenol in the concentration range of 0.0063-0.2% used 2 times daily on healthy skin can thus elicit axillary dermatitis within a few weeks in people with contact allergy to isoeugenol.  相似文献   
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