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排序方式: 共有381条查询结果,搜索用时 15 毫秒
31.
Pedersen LM Terslev L SŁrensen PG Stokholm KH 《Medical oncology (Northwood, London, England)》2000,17(2):117-122
Transcapillary escape rate of albumin was determined in 22 patients with different malignancies. In addition, urinary albumin
excretion rate was measured in 24-h urine samples using a sensitive immunoassay. Increased urinary albumin excretion was defined
as ≥20 μg/min according to conventional standards. Renal glomerular filtration and tubular function was estimated by51Cr-EDTA plasma clearance and urinary beta 2-microglobulin, respectively. Median urinary albumin excretion rate was 15.0 μg/min
(range 6–510 μg/min) and the frequency of increased urinary albumin excretion was 41%. This agrees with other studies showing
increased albuminuria in several types of malignant diseases. Patients with advanced disease (tumour, node, metastasis (TNM)
stage II–IV) had a significantly higher urinary albumin excretion rate than patients with localized disease (TNM stage I).
Serum creatinine, glomerular filtration rate and urinary beta 2-microglobulin were all within normal limits. Median transcapillary
escape rate of albumin was 5.5%/h (range 2–8%/h) and this level is comparable with values in healthy subjects. There was no
significant difference in transcapillary escape rate between patients with elevated urinary albumin excretion and the normoalbuminuric
group. Median value of the absolut outflux of albumin was 10.6 g/h with similar levels in patients with increased urinary
albumin excretion and patients with normoalbuminuria. Our results indicate a high prevalence of minor glomerular dysfunction
with a slightly elevated urinary albumin excretion in patients with malignancies. The normal endothelial function, as estimated
by the transcapillary escape rate of albumin, suggests an overal unaffected capillary permeability and increased urinary albumin
loss appears to be an isolated renal phenomenon in cancer patients. 相似文献
32.
OBJECTIVE: To determine whether children's food consumption is increased by the size of the group of children in which they are eating. DESIGN: Crossover study. SETTING: University based preschool. PARTICIPANTS: 54 children, aged 2.5-6.5 years. INTERVENTIONS: Each child ate a standardised snack in a group of three children, and in a group of nine children. MAIN OUTCOME MEASURES: Amount each individual child consumed, in grams. RESULTS: Amount eaten and snack duration were correlated (r = 0.71). The association between group size and amount eaten differed in the short (<11.4 min) versus the long (> or =11.4 min) snacks (p = 0.02 for the interaction between group size and snack duration). During short snacks, there was no effect of group size on amount eaten (16.7 (SD 11) g eaten in small groups vs 15.1 (6.6) g eaten in large groups, p = 0.42). During long snacks, large group size increased the amount eaten (34.5 (16) vs 26.5 (13.8), p = 0.02). The group size effect was partially explained by a shorter latency to begin eating, a faster eating rate and reduced social interaction in larger groups. CONCLUSIONS: Children consumed 30% more food when eating in a group of nine children than when eating in a group of three children during longer snacks. Social facilitation of food consumption operates in preschool-aged children. The group size effect merits consideration in creating eating behaviour interventions. 相似文献
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37.
Flexible tantalum stents implanted in aortas and iliac arteries: effects in normal canines 总被引:2,自引:0,他引:2
Barth KH; Virmani R; Strecker EP; Savin MA; Lindisch D; Matsumoto AH; Teitelbaum GP 《Radiology》1990,175(1):91-96
Vascular endoprostheses made of knitted tantalum wire and expanded over angioplasty balloons were placed into aortas or iliac arteries of 14 normal dogs. Twelve stents were placed into the infrarenal abdominal aorta and two stents in the left common iliac arteries by the left carotid artery approach. To firmly expand the stent against the vascular wall, nominal stent sizes 0.5-1.0 mm larger than the measured arterial diameter were required. Arteriography performed at specified follow-up intervals showed no evidence of thrombi or emboli; all side branches (lumbar arteries) covered by the stents remained patent. Vascular diameter decreased minimally at 8 and 26 weeks, associated with histopathologic evidence of neointimal buildup. This buildup was highest at 8 weeks (mean, 313 microns) and was slightly less at 26 weeks (mean, 223 microns). Almost complete coverage by endothelium was seen as early as 3 weeks. It is concluded that the flexible tantalum wire stents are well tolerated by the arterial wall and become quickly endothelialized. No excessive neointimal buildup was observed during the 6-month study. 相似文献
38.
M Sun ; KH Chao ; LE Modahl ; G Leoung ; H Khayam-Bashi ; VL Ng ; EL Murphy 《Transfusion》1994,34(4):344-348
BACKGROUND: Asian Americans are generally underrepresented both as volunteer blood and bone marrow donors. STUDY DESIGN AND METHODS: To investigate the risk of transfusion transmission of viruses that is associated with increasing participation by Asian American donors, antibodies to human T-lymphotropic virus (HTLV), hepatitis C, and human immunodeficiency virus in Asian American volunteers recruited as potential bone marrow donors were measured. A total of 1354 Asian Americans were enrolled in the study, of whom 54 percent were Chinese, 26 percent Japanese, 9 percent Filipino, 4 percent Korean, 3 percent Indian, and 5 percent of other Asian or mixed Asian and other ethnicity. The majority of the study population was aged 20 through 49 and of high socioeconomic status, as indicated by education and income. Viral antibodies were measured with both screening enzyme-linked immunosorbent assays and supplemental testing, and polymerase chain reaction was used to resolve discrepant HTLV results. RESULTS: Confirmed seroprevalence rates for HTLV were 0.15 percent with one manufacturer's Western blot and 0.3 percent with the other; however, no sample was positive for HTLV types I or II in polymerase chain reaction. Confirmed seroprevalence to hepatitis C virus was 0.5 percent. No subject was seropositive for human immunodeficiency virus. CONCLUSION: On the basis of the moderate size and high education level of this study population, it is concluded that Asian American volunteer bone marrow donors do not pose a greater risk for transmission of HTLV type I or II, human immunodeficiency virus, or hepatitis C virus than does the average American blood donor. 相似文献
39.
True or sham plasma exchange was done weekly for 20 weeks in patients in two of the randomization groups in a prospective, blind clinical trial of experimental treatments for multiple sclerosis. Because patients could be randomized to receive sham plasma exchange and placebo medications, it was decided when the trial was designed that the use of fistulae, arteriovenous shunts, venous cutdowns, or other aggressive forms of venous access would not be permitted for any patient. Accordingly, patients judged to have inadequate superficial antecubital veins were ineligible for the trial. To date, only 13 (4.4%) of 294 patients considered for entry into the trial have been rejected on these grounds. In only 4 of the 93 patients undergoing exchange was it necessary to discontinue plasma exchange because of inadequate venous access. In 79.3 percent of the 1207 exchanges done in these patients, there were no problems of any kind with venous access. In 5.4 percent of these 1207 exchanges, it was necessary to terminate the procedure prematurely because of difficulties with patients' veins. Thus, the great majority of patients free of serious systemic illness (other than chronic progressive multiple sclerosis) can undergo weekly plasma exchange for up to 20 weeks using superficial antecubital veins without the need to resort to more invasive methods of venous access. 相似文献
40.
La nécrosectomie transgastrique semble être une alternative présentant peu de risques de traitement pour les patients gravement
atteints. Cependant, il manque à ce jour, une analyse des risques du procédé sur un nombre suffisant de patients; il est urgent
de procéder à des collectes de données multicentriques. Il s’agit de procédés endoscopiques complexes, qui nécessitent une
grande expérience, et le traitement de chaque patient devrait être planifié de fa?on interdisciplinaire en collaboration avec
le chirurgien. Ce procédé devrait par conséquent rester limité aux centres spécialisés. 相似文献