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排序方式: 共有712条查询结果,搜索用时 31 毫秒
1.
2.
Ketai LH; Williamson MR; Telepak RJ; Levy H; Koster FT; Nolte KB; Allen SE 《Radiology》1994,191(3):665
3.
Braffman BH; Coleman BG; Ramchandani P; Arger PH; Nodine CF; Dinsmore BJ; Louie A; Betsch SE 《Radiology》1994,190(3):797
4.
Kinnison ML; Perler BA; Kaufman SL; Mitchell SE; Kadir S; Williams GM; White RI Jr 《Radiology》1986,160(3):727-730
In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications. 相似文献
5.
6.
Intestinal schistosomiasis japonica: CT-pathologic correlation 总被引:1,自引:0,他引:1
Lee RC; Chiang JH; Chou YH; Rubesin SE; Wu HP; Jeng WC; Hsu CC; Tiu CM; Chang T 《Radiology》1994,193(2):539
7.
Marelise E M W Eekhoff Marjolein van der Klift Herman M Kroon Cyrus Cooper Albert Hofman Huibert A P Pols Socrates E Papapoulos 《Journal of bone and mineral research》2004,19(4):566-570
Serum ALP may be a good indicator of Paget's disease in epidemiologic studies. Subjects with raised and normal ALP from a population cohort were matched (1 in 6, total 548), and radiographs were taken. ALP was an excellent marker of the disease (RR, 10.9), but the majority of those affected had normal ALP. INTRODUCTION: Evidence from radiographic surveys of limited skeletal sites has shown that Paget's disease of bone (PDB) is common in the elderly and has a distinct geographic variation. There is no information, however, about the relation of serum alkaline phosphatase (ALP) activity, a marker of the disease, and its prevalence in the population. MATERIALS AND METHODS: We analyzed data from a well-defined Dutch population cohort (the Rotterdam study) with the following specific aims: (1) to assess the relationship between serum ALP activity and prevalence of radiographically diagnosed PDB, (2) to estimate the overall prevalence of the disease in the Netherlands, and (3) to assess the appearance of the disease with time. Using a nested case-control design, subjects with an increased serum ALP and normal serum liver enzymes were matched for gender and age (1 to 6) with subjects with normal serum ALP activity. Radiographs of the thoracic and lumbar spine, pelvis, proximal femurs, knees, wrists, and hands were taken. RESULTS AND CONCLUSIONS: PDB was diagnosed in 20.5% of subjects with elevated serum ALP activity and in 2.3% in those with normal serum ALP activity, increasing with age in both groups. The relative risk (RR) for PDB in the presence of raised serum ALP activity was 10.9 (95% CI, 4.8, 24.9). The estimated prevalence of PDB in the population was 3.6%, and the large majority (about 86%) had normal serum ALP activity, contrasting findings in bone clinics where the opposite is the case. Finally, in subjects with normal and raised serum ALP activity but no PDB at baseline, radiographs taken 6-9 years later showed no evidence of the disease. This study demonstrated that serum ALP activity is a sensitive marker of PDB in men and women >55 years of age, but the majority of those affected have normal serum ALP activity. 相似文献
8.
Papapoulos S. E.; Berg H. v.d.; Frolich M.; Valentijn R. M. 《Nephrology, dialysis, transplantation》1988,3(5):647-650
The formation of 1.25-dihydroxycholecalciferol (1.25-(OH)2D3after single intravenous injections of 1-hydroxycholecalciferol(1-OHD3) was examined in four patients with chronic renal failureon regular haemodialysis. Following 13µg 1-OHD3administered at weekly intervals, 1.25-(OH)2D3 appeared in thecirculation within 1 h, and peak concentrations were reachedbetween 2 h and 5 h. By 8 h serum 1.25-(OH)2D3 concentrationshad started declining and by 44 h they had returned to baselineafter 1µg 1-OHD3 but they were still above basal after2 and 3 µg by an average of 30 pmol/l. One week afterinjections, concentrations were back to basal in all patientsstudied. The serum 1,25-(OH)2D3 dose response to injected la-OHDwas linear, indicating ample capacity of the liver 25-hydroxylaseto further hydroxylate 1-OHD. However, examination of the individualresponses revealed lower increments in serum 1.25-(OH)3 concentrationsin the patients with the highest basal serum 25-hydroxyvitaminD concen trations. Intravenous 1-OHD3 may be useful in the furtherstudy of the interactions between 1.25-(OH)23 calcium and PTHin chronic renal failure, as well as of the hepatic metabolismof vitamin D. 相似文献
9.
The effects of antioxidant supplementation during Percoll preparation on human sperm DNA integrity 总被引:20,自引:6,他引:20
Hughes CM; Lewis SE; McKelvey-Martin VJ; Thompson W 《Human reproduction (Oxford, England)》1998,13(5):1240-1247
The integrity of sperm DNA is crucial for the maintenance of genetic
health. A major source of damage is reactive oxygen species (ROS)
generation; therefore, antioxidants may afford protection to sperm DNA. The
objectives of the study were, first, to measure the effects of antioxidant
supplementation in vitro on endogenous DNA damage in spermatozoa using the
single cell gel electrophoresis (comet) assay and, second, to assess the
effect of antioxidant supplementation given prior to X-ray irradiation on
induced DNA damage. Spermatozoa from 150 patients were prepared by Percoll
centrifugation in the presence of ascorbic acid (300, 600 microM), alpha
tocopherol (30, 60 microM), urate (200, 400 microM), or acetyl cysteine (5,
10 microM). DNA damage was induced by 30 Gy X-irradiation. DNA strand
breakage was measured using the comet assay. Sperm DNA was protected from
DNA damage by ascorbic acid (600 microM), alpha tocopherol (30 and 60
microM) and urate (400 microM). These antioxidants provided protection from
subsequent DNA damage by X-ray irradiation. In contrast, acetyl cysteine or
ascorbate and alpha tocopherol together induced further DNA damage.
Supplementation in vitro with the antioxidants ascorbate, urate and alpha
tocopherol separately has beneficial effects for sperm DNA integrity.
相似文献
10.
Kirkpatrick SE; Pitlick PT; Naliboff J; Friedman WF 《The American journal of physiology》1976,231(2):495-500