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排序方式: 共有853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.
A Holte 《Maturitas》1992,14(2):127-141
As a continuation of a cross-sectional study in 1981 involving a representative sample of 1886 women between 45 and 55 years of age, 200 pre-menopausal subjects were selected randomly to take part in a follow-up study. Eighty-seven single measures covering 26 areas of health complaints which have been associated with the menopause in medical textbooks were investigated. A tentative method for relating health complaints at several time points to menopausal status is proposed. A significant number of women reported an increase in vasomotor complaints, vaginal dryness, heart palpitations and social dysfunction following the menopause, although many reported no change or even a reduction in these complaints. On the other hand, a decrease in headache and breast tenderness was noted. No significant differences were observed between the numbers of women reporting an increase or a decrease respectively on any of the other 69 measures (20 complaints), which included anxiety, depression and irritability. Further analyses indicated that the increase in social dysfunction was caused by hot flushes and sweating. This paper raises a number of issues regarding the methodology of longitudinal studies. 相似文献
5.
Anterior lumbar fusion using a hybrid interbody graft 总被引:3,自引:0,他引:3
Summary This is a radiographic report of 40 patients (20 men, 20 women) who underwent anterior lumbar interbody fusions (73 levels)
utilizing a “hybrid” interbody graft composed of femoral cortical allograft (FCA) bone and iliac crest cancellous autograft
bone. The average age at surgery was 38 years (range 17–64 years), and follow-up averaged 1.4 years (range 1.0–2.4 years).
Nineteen of the patients had undergone previous lumbar surgery. Thirty-two patients (63 levels) underwent anterior fusion
combined with some type of posterior fixation, and eight patients (10 levels) had no posterior fixation. Types of posterior
fixation included: for 20 patients (36 levels) Steffee variable screw placement fixation, for 10 patients (23 levels) translaminar
facet screws (TFS), for 1 patient (3 levels) Knodt rods and for 1 patient (1 level) facet screws. Based on the persistence
of lucent lines at the graft-host interface, three patients (one level each) were felt to have non-unions at their latest
follow-ups at 1.4, 1.5 and 2.0 years, respectively. Two of these patients had no posterior fixation, and the other had TFS
fixation. The overall fusion rate was 96% (70 of 73 levels). The fusion rate for all levels treated with posterior fixation
was 98% compared with 75% for those without fixation. Intervertebral disc heights (IVDH) were measured on all films and corrected
for magnification with computer assistance. On average, the IVDH was increased postoperatively but returned to preoperative
values at follow-up. IVDH loss was independent of the type of instrumentation used. No complications arose from the use of
the hybrid graft. Incorporation of the allograft portion of the graft is slow and was felt to be complete in only 7 of the
73 levels at follow-up. We conclude that the hybrid interbody graft technique is a safe and reliable method for performing
anterior lumbar interbody fusions and should be combined with some type of posterior fixation. Long-term follow-up will be
required to assess the behaviour of the allograft until incorporation is complete. 相似文献
6.
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
7.
8.
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
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