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81.
Twenty-nine New Zealand white rabbits were allocated to undergo insertion of either polytetrafluoroethylene (PTFE) (n = 22) or microporous silicone rubber (SR) (n = 7), 3-mm diameter, 10-mm long aortic grafts. Animals with PTFE grafts received aspirin (ASA) 10 mg/kg/d and dipyridamole (DPM) 10 mg/kg/d (n = 11) or placebo (n = 11). Autologous In-111-oxine-labeled platelets were reinfused on reestablishment of blood flow through the graft. Using gamma camera images, an external graft platelet accumulation index (E-GPAI) was calculated as the In-111 activity in the graft area to the reference aorta at 24, 48, and 72 hours post implantation. Mean E-GPAI +/- SEM values for the ASA/DPM (n = 4) and control groups (n = 7) were 1.13 +/- 0.16 and 1.34 +/- 0.05 (NS) at 24 hours, 1.20 +/- 0.16 and 1.33 +/- 0.07 (NS) at 48 hours, and 1.38 +/- 0.07 and 1.35 +/- 0.10 (NS) at 72 hours, respectively. A similar internal graft platelet accumulation index (I-GPAI) was constructed based on In-111 activity in excised grafts and reference aorta measured in a scintillation counter. Mean I-GPAI +/- SEM values for the PTFE ASA/DPM (n = 9) and control groups (n = 8) at 48 hours post implantation were 43.1 +/- 2.7 and 216.8 +/- 73.9 (P = 0.05), respectively. I-GPAI values for the SR grafts were 192.5 +/- 43.1. Conclusion: The E-GPAI was not sensitive enough to demonstrate the effect of antiplatelet medication on platelet accumulation on the PTFE grafts.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
82.
Vol. 33(4) 2003, pp 880‐888 Pages 882 (Fig. 2) and 883 (Fig. 5) The x‐axis label in Fig. 2 should have the same sampling times post‐infection as Fig. 1. The legend to Fig. 5 should be amended to read: blue nuclei, red collagen and yellow connective tissue or hepatic parenchyma.  相似文献   
83.
During a 3-year period we studied 393 adult patients (382 of whom were unrelated) with a history of acute venous thromboembolism. A congenital deficiency state known to predispose to thrombosis was found in 27.2%. Of these, most were due to deficiencies of protein C (9.2%), protein S (7.6%), antithrombin III (5%) or to increased plasma PAI-1 concentration (3.1%) which, in the absence of any known factor that predisposes towards thrombosis, results in a diminished fibrinolytic activity. There was a characteristic pattern between the age of onset (mean 34 years) of thrombosis and individual protein deficiency. Thrombosis appeared spontaneously in 73% of cases with recurrence in 80%. In contrast, in the remaining unrelated patients, 138 (35.1%) in whom venous thromboembolism was secondary and occurred at a mean age of 43 years, and in the other 140 (35.6%) who suffered thromboembolism spontaneously at a later age (mean age 55), there was no permanent protein deficiency state or alteration in fibrinolytic activity and thrombosis recurrence was lower (53.6% and 20.7% respectively). Of the 393 patients, deep vein thrombosis was the most common manifestation; however, in congenital thrombophilia, thrombosis of visceral vessels and Raynaud's syndrome (6%) were also detected.  相似文献   
84.
A randomized trial of a family physician intervention for smoking cessation   总被引:13,自引:0,他引:13  
We assessed the impact of three conditions on one-year smoking cessation rates. Physicians in 70 community general practices were randomly allocated by practice to one of three groups: In the usual care group, smoking patients were to receive the care they normally would receive. In the gum only group, physicians were asked to speak to patients about smoking cessation and offer nicotine gum. In the gum plus group, physicians were trained in the experimental intervention. This intervention involved advice to stop smoking, the setting of a quit date, the offer of nicotine gum, and four follow-up visits. Smoking cessation was measured by self-report after one year and validated using saliva cotinine measures. Using a criterion of at least three months of abstinence, 8.8% of the patients of the trained physicians had stopped smoking at the one-year follow-up compared with 4.4% and 6.1% of the patients in the usual care and gum only groups, respectively.  相似文献   
85.
A new hemoglobin variant with a Ser----Phe substitution at position beta 49(CD8) was discovered in two members of a family living in the Canary Islands, Spain. Detection was by polyacrylamide gel electrophoresis and by reversed phase high performance liquid chromatography. The variant, which constituted 43% and 45%, respectively, in the two heterozygotes, was slightly unstable. Its presence did not affect hematological values though there was a mild reticulocytosis.  相似文献   
86.
The proliferative potential of low-grade astrocytomas was estimated in 47 patients. Each patient received an intravenous infusion of bromodeoxyuridine (BUdR), 150 to 200 mg/sq m, at the time of craniotomy to label cells in deoxyribonucleic acid (DNA) synthesis; the percentage of S-phase cells, or BUdR labeling index (LI), of each tumor was determined immunohistochemically. In 29 patients (60%), the tumors had BUdR LI's of less than 1%, indicating a slow growth rate; only three (10%) of these patients died of recurrent tumor during a follow-up period of up to 3 1/2 years. In contrast, of the 18 patients (40%) whose tumors had BUdR LI's of 1% or more, 12 (67%) had a recurrence and nine died during the same follow-up period. These results show that the proliferative potential, as reflected by the BUdR LI, is an important prognostic factor that separates low-grade astrocytomas into two groups and provides a more scientific rationale for selecting treatment for individual patients.  相似文献   
87.
It has been suggested that delayed repair with preoperative stabilization might improve survival in high-risk (symptomatic within 6 hours of birth) congenital diaphragmatic hernia (CDH). This study compares the results of immediate operation versus delayed repair using extracorporeal membrane oxygenation (ECMO) when necessary. Since we first used ECMO in 1984, 101 high-risk CDH infants have been treated. Prior to 1987, we used immediate repair and postoperative ECMO if necessary. Between 1987 and 1990 we combined delayed operation (24 to 36 hours) with preoperative ECMO as necessary. No infant in this series was excluded from ECMO therapy unless absolute contraindications existed (prematurity, intracranial hemorrhage, or other major anomalies). Fifty-five patients received immediate operation and 46 had delayed repair. The two groups were comparable populations based on gestational age, birth weight, age at onset of symptoms, Apgar scores, best postductal PO2 (BPDPO2), and frequency of antenatal diagnosis. There was no statistically significant difference in overall survival between the two groups. Differences in survival among subpopulations (BPDPO2 greater than 100 or less than 100, antenatal diagnosis, inborn v outborn) also are not significant. The requirement for ECMO was similar in both groups. Survivors in the delayed repair group were ventilated longer and on ECMO longer, but had fewer late deaths (greater than 21 days) and fewer pulmonary sequelae (O2 dependency at discharge) than infants in the immediate repair group (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
88.
MR imaging of spinal cord hemangioblastoma associated with syringomyelia   总被引:1,自引:0,他引:1  
A case of isolated spinal cord hemangioblastoma with associated extensive syringohydromyelia, which was evaluated by myelography, postmyelographic CT, magnetic resonance (MR), and angiography is presented. The specific preoperative and postoperative advantages of MR are given as well as a brief review of the literature.  相似文献   
89.
Seventy-one neuropathic ulcers of the foot in sixty-six patients were treated with the use of a total-contact cast. The ulcers had been present for an average of five months (range, one to twenty-nine months) and were graded according to the Wagner classification; only patients who had grade-I or grade-II lesions were treated with a total-contact cast. The diameter of the ulcer averaged 3.5 centimeters (range, 1.5 to 15.5 centimeters). Sixty-four (90 per cent) of seventy-one ulcers were healed at a mean of five and one-half weeks (range, one to fourteen weeks). A deep infection developed in two patients during treatment. Twenty-two ulcers (31 per cent) recurred within eighteen months after initial healing; nineteen (86 per cent) of them healed after an average of two weeks in a second cast. Recurrent ulceration was usually associated with an underlying fixed deformity or osseous prominence. The total-contact cast provided safe, reliable, and cost-effective treatment for patients who had neuropathic ulcers of the foot.  相似文献   
90.
Myotonic dystrophy is an autosomal dominant disorder in which an early-onset form is characteristically inherited from the mother. We studied 17 affected sibling pairs from 15 families in which two or more affected children were born to mothers with myotonic dystrophy. Later-born affected children suffered more severe disease than their first-born siblings in 13 of 17 sibling pairs. Later-born affected siblings displayed significantly more neonatal feeding difficulties, later age when first sitting alone, later age when first walking alone, and a higher incidence of scoliosis. The overall difference in disease severity between affected siblings increased as the age difference between them increased, suggesting that increasing maternal age is a factor in the relative disease severity of affected children. These findings may have relevance for genetic counseling.  相似文献   
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