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排序方式: 共有892条查询结果,搜索用时 78 毫秒
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Ketai LH; Williamson MR; Telepak RJ; Levy H; Koster FT; Nolte KB; Allen SE 《Radiology》1994,191(3):665
4.
Braffman BH; Coleman BG; Ramchandani P; Arger PH; Nodine CF; Dinsmore BJ; Louie A; Betsch SE 《Radiology》1994,190(3):797
5.
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
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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
8.
Beta-adrenergic stimulation and alpha 2-adrenergic inhibition increase lipolysis from fat cells. Twenty-eight obese women were placed on a calorie-restricted diet and one of five treatments was applied to one thigh three to five times per week for four weeks: (1) isoproterenol injections; (2) cream containing colforsin (forskolin), aminophylline, and yohimbine; (3) yohimbine cream; (4) colforsin cream; or (5) aminophylline cream. The opposite thigh was treated with a placebo (injection or cream). The treated thighs lost significantly more girth after treatment, both by injection and by cream. No adverse reactions were attributable to either the cream or the injections. It is concluded that local fat reduction from the thigh can be safely accomplished. 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.
The effect of haemorrhage on venous return and regional blood flow in the anaesthetized cat 总被引:2,自引:0,他引:2
1. In cats under pentobarbitone anaesthesia, a venous long-circuit technique was used to measure the blood flows in the superior vena cava and the hepatic, renal and iliac segments of the inferior vena cava. The sum of these flows gave the venous return (minus coronary and bronchial flows).2. In these preparations, the mean venous return was 130 ml./kg. Of this 28% came from the superior vena cava and 37% from the hepatic, 23% from the renal and 12% from the iliac segments of the inferior vena cava.3. After haemorrhage, the flows from all the venae cavae segments decreased. The quantitative changes varied with the particular cat, the degree and duration of the haemorrhage and whether the animal had been subjected to a previous haemorrhage.4. The proportion of the reduced venous return draining from the superior vena cava and the hepatic segment increased, that draining from the renal and iliac segments decreased. Vasoconstriction occurred in all vascular beds, but was greatest in the kidney and hind limbs. Thus the blood flow through the head and liver was partially maintained at the expense of that through the kidneys and hind limbs.5. Autoregulation of blood flow in the kidneys was usually seen immediately after the first removal of blood but with the onset of renal vasoconstriction it was reduced or abolished for the remainder of the experiment. 相似文献