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排序方式: 共有4240条查询结果,搜索用时 15 毫秒
91.
92.
Paolo Ventura Herbert L. Bonkovsky Laurent Gouya Paula Aguilera-Peir D. Montgomery Bissell Penelope E. Stein Manisha Balwani D. Karl E. Anderson Charles Parker David J. Kuter Susana Monroy Jeeyoung Oh Bruce Ritchie John J. Ko Zhaowei Hua Marianne T. Sweetser Eliane Sardh 《Liver international》2022,42(1):i-i
93.
Marianne Ritchie MD James Caravelli MD Dr. Moshe Shike MD 《Digestive diseases and sciences》1986,31(5):552-555
Summary We present a 68-year-old patient who, over a two-year period, was observed to have persistent benign pneumoperitoneum. The free air was present in the abdominal cavity without gastrointestinal perforation or pneumatosis cystoides intestinalis. The persistent pneumoperitoneum was a benign process and was not associated with peritonitis or other ill effects. The source of the free air was not clear. Conceivably, microperforations occurring in colonic diverticula or in distended intestinal wall induced the persistent benign pneumoperitoneum. 相似文献
94.
Dr. Robert H. Thorlakson M.D.; F.R.C.S. F.R.C.S.C. F.A.CS. 《Diseases of the colon and rectum》1986,29(9):591-593
A set of double-angled needle holders and long, angled tissue forceps have been designed and presented for use in surgery
of the abdomen. The problems of passage and control of curved needles in all directions is well recognized. The marriage of
design and presentation addresses the mechanical and anatomic needs of surgeons in the pelvis, subdiaphragmatic area, and
in large and obese patients. Multiple variables in use provided by these instruments, particularly when used together, enhance
surgical control at problem sites. 相似文献
95.
Comparative plasma catecholamine and hemodynamic responses to handgrip, cold pressor and supine bicycle exercise testing in normal subjects 总被引:2,自引:0,他引:2
J R Stratton J B Halter A P Hallstrom J H Caldwell J L Ritchie 《Journal of the American College of Cardiology》1983,2(1):93-104
Serial hemodynamic and plasma catecholamine responses were compared among 10 healthy men (27 +/- 3 years) (+/- 1 standard deviation) during symptom-limited handgrip (33% maximal voluntary contraction for 4.4 +/- 1.8 minutes), cold pressor testing (6 minutes) and symptom-limited supine bicycle exercise (22 +/- 5 minutes). Plasma catecholamine concentrations were measured by radioenzymatic assays: ejection fraction and changes in cardiac volumes were assessed by equilibrium radionuclide angiography. During maximal supine exercise, plasma norepinephrine and epinephrine concentrations increased three to six times more than during either symptom-limited handgrip or cold pressor testing. Additionally, increases in heart rate, systolic blood pressure, rate-pressure product, stroke volume, ejection fraction and cardiac output were significantly greater during bicycle exercise than during the other two tests. A decrease in ejection fraction of 0.05 units or more was common in young normal subjects during the first 2 minutes of cold pressor testing (6 of 10 subjects) or at symptom-limited handgrip (3 of 10), but never occurred during maximal supine bicycle exercise. The magnitude of hemodynamic changes with maximal supine bicycle exercise was greater, more consistent and associated with much higher sympathetic nervous system activation, making this a potentially more useful diagnostic stress than either handgrip exercise or cold pressor testing. 相似文献
96.
D B Wile M Barbir J Gallagher N B Myant C D Ritchie G R Thompson S E Humphries 《Atherosclerosis》1989,78(1):9-18
We have investigated the association between serum high density lipoprotein-cholesterol (HDL-C) and apo A-I concentration and the PstI and XmnI restriction fragment length polymorphisms of the apolipoprotein AI-CIII-AIV multigene complex. Two groups of subjects were examined. The first comprised 174 unrelated male patients under 60 years of age with angiographic evidence of coronary artery disease (CAD). Of this group 34 were non-North European. The second group consisted of 104 unrelated healthy male North European subjects aged under 60 and free from demonstrable CAD, who attended a health screening clinic in London. For the PstI polymorphism, the frequency of the rarer P2 allele was 0.12 in both the North European and non-North European patients and this was higher than in the control group (P2 frequency 0.06, P less than 0.05). Healthy individuals with the genotype P1P2 had higher levels of apo A-I but similar levels of HDL-C compared to those with the genotype P1P1. However, CAD patients with the genotype P1P2 had lower serum levels of apo A-I and significantly lower serum levels of HDL-C compared to those with the genotype P1P1 (0.85 mmol/l vs. 1.0 mmol/l, P less than 0.05). The allele frequencies of the XmnI polymorphisms were not significantly different in the control group and the group of North European patients, although within the sample of non-North European patients, the frequency of the X2 allele was significantly higher than that found in the North European controls (0.26 vs. 0.09). Patients with the genotype X1X2 had a higher mean serum concentration of HDL-C and apo A-I compared with patients with the genotype X1X1 (1.14 and 0.93 mmol/l for HDL-C, P less than 0.05; 147 and 123 mg/dl for apo A-I, P less than 0.05). Associations between HDL-C and apo A-I levels and PstI and XmnI genotype were similar in patients taking and not taking beta-blockers. The data show that genetic variation in the apo AI-CIII-AIV gene cluster is associated with coronary artery disease although only weakly, and suggest that the mechanism of this association may operate through an effect in determining the serum concentration of apo A-I and HDL-cholesterol. 相似文献
97.
Myocardial imaging with thallium-201: a multicenter study in patients with angina pectoris or acute myocardial infarction 总被引:7,自引:0,他引:7
J L Ritchie B L Zaret H W Strauss B Pitt D S Berman H R Schelbert W L Ashburn H J Berger G W Hamilton 《The American journal of cardiology》1978,42(3):345-350
A multicenter study of rest and exercise thallium-201 myocardial imaging in 190 patients from five centers was performed. Exercise images were obtained after graded treadmill or bicycle stress with use of five different gamma camera models and were interpreted by the originating investigator without knowledge of other clinical data. Of 42 patients with less than 50 percent coronary stenosis, 4 (10 percent) had a resting image defect, 1 (2 percent) a new exercise defect and 5 (12 percent) either a resting or an exercise image defect, or both. Of 148 patients with coronary stenosis of 50 percent or greater, 64, (45 percent) had an image defect in the study at rest, 90 (61 percent) had new or increased defects after exercise, and 115 (78 percent) had resting or exercise defects, or both. New exercise image defects were more common than exercise S-T depression (90 of 148 [61 percent] versus 62 of 148[42 percent]; P less than 0.01). In a second group of 111 patients with acute myocardial infarction studied at three centers, 90 patients (81 percent) had image defects compared with 71 (64 percent) two had new electrocardiographic Q waves (P less than 0.01). Smaller infractions, as assessed with serum enzyme values, and diaphragmatic infarctions were less commonly detected than larger or anterior infarctions. These findings suggest that myocardial imaging complements the electrocardiographic identification of acute myocardial infarction of exericse-induced myocardial ischemia. 相似文献
98.
Patients with left ventricular thrombi not caused by recent myocardial infarction were prospectively studied by indium-111 platelet imaging and two-dimensional echocardiography to determine the reproducibility of these techniques and the short-term effects of sulfinpyrazone (200 mg four times daily), aspirin (325 mg three times daily) plus dipyridamole (75 mg three times daily), and full-dose warfarin. At baseline, all patients underwent indium-111 platelet imaging and echocardiography, and the results were positive for thrombus. In six patients on no antithrombotic drug therapy, repeat platelet scans and echocardiographic studies at 6.0 +/- 3.3 weeks remained positive and were unchanged. In seven patients studied on sulfinpyrazone, three platelet scans became negative, two became equivocal, and two were unchanged; the presence and size of thrombus was constant by echocardiography in all seven patients. Of the six patients studied on aspirin plus dipyridamole, one platelet scan became negative, those of three became equivocal, and two were unchanged; all echocardiographic findings remained positive, but one patient had decreased thrombus size. Among four warfarin-treated patients, three had resolution of platelet deposition and one was unchanged; by echocardiography, thrombus resolved in one patient, was decreased in size in one, and was unchanged in two. We conclude that, in the absence of antithrombotic drug therapy, platelet imaging and echocardiographic findings are stable in patients with left ventricular thrombi not caused by recent myocardial infarction. Sulfinpyrazone, aspirin plus dipyridamole, and warfarin all interrupt platelet deposition in some patients with chronic left ventricular thrombi.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
99.
To determine whether a positive indium 111 platelet image for a left ventricular thrombus, which indicates ongoing thrombogenic activity, predicts an increased risk of systemic embolization, we compared the embolic rate in 34 patients with positive 111In platelet images with that in 69 patients with negative images during a mean follow-up of 38 +/- 31 (+/- SD) months after platelet imaging. The positive and negative image groups were similar with respect to age (59 +/- 11 vs. 62 +/- 10 years), prevalence of previous infarction (94% vs. 78%, p less than 0.05), time from last infarction (28 +/- 51 vs. 33 +/- 47 months), ejection fraction (29 +/- 14 vs. 33 +/- 14), long-term or paroxysmal atrial fibrillation (15% vs. 26%), warfarin therapy during follow-up (26% vs. 20%), platelet-inhibitory therapy during follow-up (50% vs. 33%), injected 111In dose (330 +/- 92 vs. 344 +/- 118 microCi), and latest imaging time (greater than or equal to 48 hours in all patients). During follow-up, embolic events occurred in 21% (seven of 34) of patients with positive platelet images for left ventricular thrombi as compared with 3% (two of 69) of patients with negative images (p = 0.002). By actuarial methods, at 42 months after platelet imaging, only 86% of patients with positive images were embolus free as compared with 98% of patients with negative images (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
100.
Ritchie DS Szer J Roberts AW Shuttleworth P Grigg AP 《Bone marrow transplantation》2002,30(10):645-650
Relapse of the primary disease remains the predominant cause of death following bone marrow transplantation for high-risk haematological malignancies. Improved supportive care and patient selection have resulted significant improvements in toxicity with standard conditioning regimens. Further dose intensification to reduce the risk of relapse may therefore be feasible. We determined the maximal tolerated dose (MTD) of a 5-day continuous infusion (CI) of etoposide when added to oral busulphan 16 mg/kg and intravenous cyclophosphamide 120 mg/kg (Bu/Cy) as conditioning in 44 autograft and 18 allograft recipients at high risk of relapse. The major toxicity of escalating doses of etoposide was oral and gastro-intestinal mucositis, reflected by a statistically significant increase in the requirement for total parenteral nutrition in both autografts and allograft recipients. Time to neutrophil and platelet recovery, opiate analgesia requirements, and duration of hospitalization were not affected by etoposide dose escalation. The MTD in autograft recipients was 300 mg/m(2)/day (1500 mg/m(2) total dose), and 100 mg/m(2)/day (500 mg/m(2) total dose) for allograft recipients. Mucositis and hepatotoxicity were more frequent in allograft recipients, suggesting that methotrexate may have contributed to the lower tolerable dose in these patients. As a consequence, further dose escalation may not be possible in heavily pre-treated patients undergoing allogeneic transplantation. Conversely, high dose CI etoposide can be added with relative safety to Bu/Cy in autograft recipients. 相似文献