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1.

Objectives

Short successive periods of skeletal muscle disuse have been suggested to substantially contribute to the observed loss of skeletal muscle mass over the life span. Hospitalization of older individuals due to acute illness, injury, or major surgery generally results in a mean hospital stay of 5 to 7 days, during which the level of physical activity is strongly reduced. We hypothesized that hospitalization following elective total hip arthroplasty is accompanied by substantial leg muscle atrophy in older men and women.

Design and participants

Twenty-six older patients (75 ± 1 years) undergoing elective total hip arthroplasty participated in this observational study.

Measurements

On hospital admission and on the day of discharge, computed tomographic (CT) scans were performed to assess muscle cross-sectional area (CSA) of both legs. During surgery and on the day of hospital discharge, a skeletal muscle biopsy was taken from the m. vastus lateralis of the operated leg to assess muscle fiber type–specific CSA.

Results

An average of 5.6 ± 0.3 days of hospitalization resulted in a significant decline in quadriceps (?3.4% ± 1.0%) and thigh muscle CSA (?4.2% ± 1.1%) in the nonoperated leg (P < .05). Edema resulted in a 10.3% ± 1.7% increase in leg CSA in the operated leg (P < .05). At hospital admission, muscle fiber CSA was smaller in the type II vs type I fibers (3326 ± 253 μm2 vs 4075 ± 279 μm2, respectively; P < .05). During hospitalization, type I and II muscle fiber CSA tended to increase, likely due to edema in the operated leg (P = .10).

Conclusions

Six days of hospitalization following elective total hip arthroplasty leads to substantial leg muscle atrophy in older patients. Effective intervention strategies are warranted to prevent the loss of muscle mass induced by short periods of muscle disuse during hospitalization.  相似文献   
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HOCK LEONG EE  MBBS  MRCP    CHEE LEOK GOH  MBBS  FRCP    KHOO    ES-Y. CHAN  PHD    POR ANG  MBBS  MRCP 《Dermatologic surgery》2006,32(1):34-40
BACKGROUND: Acquired bilateral nevus of Ota-like macules (Hori's nevus) is a common dyschromatosis among Asian women. Q-switched lasers have been used successfully as a treatment modality. OBJECTIVE: The purpose of this study was to compare the efficacy of using the Q-switched 532 nm neodymium:yttrium-aluminum-garnet (Nd:YAG) laser followed by the 1,064 nm laser versus the Q-switched 1,064 nm Nd:YAG laser alone in the treatment of Hori's nevus. METHODS: This is a prospective left-right comparative study. Ten women with bilateral Hori's nevus were recruited and treated with a combination of the Q-switched 532 and 1,064 nm Nd:YAG lasers on the right cheek and the Q-switched 1,064 nm Nd:YAG laser alone on the left cheek. Only one laser treatment session was performed. The degree of pigmentation was objectively recorded with a mexameter. Subjective assessment was made by both patients and two blinded, nontreating dermatologists. RESULTS: At 6 months, there was a statistically significant difference (p = .009) of 35.10 points using objective mexameter measurements between the two sides, favoring the side treated with a combination of 532 and 1,064 nm laser treatment. Subjective grading by the patients and blinded dermatologists also confirmed that combination therapy was more successful after one treatment. Although combination treatment had a higher incidence of mild postinflammatory changes, this disappeared within 2 months. CONCLUSIONS: Concurrent use of the Q-switched 532 nm Nd:YAG laser in combination with the 1,064 nm laser is more effective in pigment clearance than the Q-switched 1,064 nm Nd:YAG laser alone for Hori's nevi.  相似文献   
4.
Kim  EE; Pjura  G; Lowry  P; Verani  R; Sandler  C; Flechner  S; Kahan  B 《Radiology》1986,159(2):443-446
Serial radionuclide studies using both Tc-99m DTPA (perfusion) and I-131 hippuran (tubular function) were correlated with histologic findings in 25 patients with renal transplants. These cases included 15 cases of cyclosporin-A nephrotoxicity (CsA-NT) and ten cases of acute cellular rejection that were retrospectively selected on the basis of biopsy findings and favorable clinical response to therapy specific for each of these conditions. The serial radionuclide studies enabled the correct diagnosis in 12 of 15 cases of CsA-NT and eight of ten cases of acute rejection. Posttherapy radionuclide studies, furthermore, demonstrated improvement consistent with clinical response. In all cases, the radionuclide results were available at least 24 hours before biopsy findings. These results indicate that serial radionuclide studies evaluating interval changes in both perfusion and tubular function are of significant value in the diagnosis and follow-up of CsA-NT and acute cellular rejection in transplant recipients. This initial experience suggests a sensitivity of 80%.  相似文献   
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6.
Fluorescence in situ hybridization (FISH) was used to study numerical and structural chromosome 1 aberrations in interphase nuclei of transitional cell carcinomas (TCCs) of the urinary bladder. One of the characteristic numerical aberrations, as detected previously in low-grade noninvasive TCCs, included trisomy for chromosome 1 (A. H. N. Hopman et al., Cancer Res., 51: 644-651, 1991). We examined in more detail 22 cases with a centromeric (1q12) and a telomeric associated (1p36) DNA probe and with a library DNA probe from sorted human chromosome 1 in single- and double-target FISH procedures. All flow cytometrically determined DNA diploid TCCs (13 cases), which showed three spots for 1q12 (6 cases), had two spots for 1p36. Since the library DNA probe showed three separate domains in the nuclei of these cases, the additional copy for 1q12 could be explained as an extra chromosome 1p-, containing the 1q12 target. In the flow cytometrically determined DNA tetraploid/aneuploid tumors, the results were more complex. In 6 of 9 cases, we observed an overrepresentation of 1q12 as compared to 1p36, also suggesting the presence of extra copies of 1p- chromosomes. The results of the present study demonstrate the utility of the FISH method to assess structural chromosome aberrations in interphase nuclei of solid tumors.  相似文献   
7.
Summary It has been suggested that the reduced resistance of patients with rheumatoid arthritis (RA) to bacterial joint infections may be due in part to polymorphonuclear cell (PMN) function. To obtain further insight into the mechanis that contribute to the increased susceptiblity of RA patients to such infections we investigated the influence of different solid surfaces on the ingestion of various bacterial strains by PMN. Both in the presence and absence of serum, phagocytosis of bacteria by PMN was significantly lower on monolayers of synovial fibroblasts as compared to monolayers of endothelial cells and embryonic fibroblasts. It could be shown that the relative influence of the solid surfac on the results of the phagocytosis assay increased when decreasing concentrations of purified IgG were used. The results of this study sugpurified IgG were used. The results of this study suggested that the effect of synovial fibroblasts on PMB may lead to reduced clearance of bacteria from the joint.  相似文献   
8.
Background: The effects of tailored intervention on multiple behaviors and possible moderators of tailoring effects have not yet been sufficiently demonstrated.Purpose: The purpose of this study was to examine the effectiveness of a computer-tailored intervention on smoking; physical activity; and fruit, vegetable, and fat intake; and to test potential moderators of the effectiveness (BMI, age, SES, gender, motivation, and the number of behaviors for which respondents met the recommendations from national guidelines).Methods: Respondents were randomly assigned to a tailored intervention group, receiving one tailored letter on all of these behaviors, or a control intervention group, receiving one general information letter on all behaviors.Results: Three months after the baseline assessment, the tailored intervention group showed significantly better effects than the control group for all behaviors studied, except for smoking. Notably, the intervention did not enhance the health behaviors, but rather reduced a decline in these behaviors during the 3-month study interval. Effect sizes were small. No moderating factors were found, except for the number of behaviors for which recommendations were met in the tailoring intervention group on fruit consumption. The largest effects of the tailored intervention were found for fruit in respondents who did not meet the recommendations for any behavior (Cohen’s d=0.3).Conclusions: A tailored intervention on multiple behaviors had significant, but limited effects when compared to generic information. The number of bad habits influenced the effects of the tailored intervention on fruit consumption.  相似文献   
9.
In a randomized, double-blind, crossover cumulative study, the individual maximal bronchodilator dosages for formoterol (F) and salbutamol (S) were assessed for their respective influence on ECG, pulse rate, and serum potassium levels in 13 patients with stable and reversible asthma. The following dosages were administered with an interval of 1 h: 12-24-48-(48)-(48) micrograms for F and 100-200-400-400-(400)-(400) micrograms for S. The study day was discontinued if pulse rate was above 140 beats min-1, a flattening of T wave on the ECG was recorded, or a maximal bronchodilation in FEV1 was observed (above 110 percent of the predicted value or an increase in FEV1 in the last two measurements below 5 percent). The maximal individual dose of F administered was 84 micrograms in six patients, 132 micrograms in three patients, 180 micrograms in three patients, and 228 micrograms in one patient. For S, the maximal individual dose was 400 micrograms in three patients, 2,200 micrograms in eight patients, 3,000 micrograms in one patient, and 3,800 micrograms in one patient. The mean maximal increase in FEV1 was 36.0 percent after F and 35.1 percent after S. Pulse rate increased from 73 to S3 beats.min-1 after F and from 75 to 84 beats.min-1 after S (both statistically significant). No pulse rate above 140 beats.min-1 was observed. In the high-therapeutic range (up to 36 micrograms of F and 6,090 micrograms of S), no changes in potassium level were observed. In still higher dosages, mean potassium level decreased from 4.16 to 3.78 mmol.L-1 after F and from 4.02 to 3.88 mmol.L-1 after S (not clinically relevant). The lowest individual potassium level recorded was 3.1 mmol.L-1. No clinically important changes in ECG were observed. In conclusion, very high doses of F and S administered from a metered dose inhaler proved to be safe for patients.  相似文献   
10.
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