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991.
Constantinos Anagnostopoulos Mark G. Gunning Dudley J. Pennell Robin Laney Haralambos Proukakis S. Richard Underwood 《European journal of nuclear medicine and molecular imaging》1996,23(8):909-916
We have validated ECG-gated emission tomography using technetium-99m methoxyisobutylisonitrile for the assessment of regional ventricular function by comparing it with cine magnetic resonance imaging (MRI). Gated tomography was performed at rest in 24 patients referred for myocardial perfusion imaging [17 males and seven females with a mean age of 58 years, nine of whom had had a previous myocardial infarction (MI)]. Scores were assigned to each of nine myocardial segments for wall motion and for thickening. Cine MRI was analysed in an identical fashion. Four out of 216 (2%) segments were uninterpretable by gated tomography because of inadequate tracer uptake. In eight patients without coronary artery disease (CAD), wall motion and thickening were normal by both methods. Gated tomography showed abnormal wall motion or thickening in all patients with previous MI and in five of seven patients with CAD but no prior MI. Association between wall motion and thickening was good (r
s=0.86). Overall, there was good agreement between gated tomography and MRI for both wall motion (178/212 segments, =0.66) and wall thickening (184/212 segments, =0.69). In segments with severely reduced perfusion, however, there was poorer agreement (=0.31). Interobserver and intraobserver agreement was high ( from 0.61 to 0.78). Thus, in patients investigated for CAD, there is good overall agreement between gated tomography and MRI but the agreement is lower in segments with severe perfusion defects. 相似文献
992.
Michael Gottsauner-Wolf Johanna Schedimayer-Duit Gerold Porenta Marianne Gwechenberger Kurt Huber Dietmar Giogar Peter Probst Heinz Sochor 《European journal of nuclear medicine and molecular imaging》1996,23(12):1613-1618
Measurement of global left ventricular function is important in the follow-up of cardiac patients and is a good prognostic indicator in acute cardiac situations. We compared quantitative measurements of global left ventricular function made with radionuclide angiography (RNA) and contrast cardiac ventriculography (CVG) to visual semiquantitative estimates from two-dimensional echocardiographic images (2D-echo). Three hundred and thirty-nine consecutive patients who underwent RNA were assessed with 2D-echo within 3 months. In addition, 92 of these patients also underwent CVG (correlation of ejection fraction between CVG and RNA:r=0.82;P<0.0001). The RNA mean ejection fractions in the four 2D-echo groups (0=normal, 1=slightly, 2=moderate, or 3=severe reduced left ventricular function) differed markedly (P<0.0001); however, there was overlapping among the groups (2D-echo score/RNA ejection fraction: 0=57.3%±12.8%; 1=46.0%±12.9%; 2=29.6%±12.2%; and 3=24.6%±11.5%) and the difference between 2D-echo scores 2 and 3 was not significant. 2D-echo showed a good concordance in RNA classes (0=505; 1=35%–49%; 2=21%–34%; and 3=520% ejection fraction) 0 (133/166; 80%) and 3 (18/30; 60%) but low concordance in classes 1 (27/82; 33%) and 2 (21/61; 34%). For accurate assessment of global left ventricular ejection fraction, visual semiquantitative judgement of a 2D echocardiographic image is limited in comparison to CVG or RNA, especially in patients with a slight or moderate reduction in left ventricular ejection fraction. 相似文献
993.
L. Vinter-Jensen M. Smerup P. E. Jørgensen C. O. Juhl T. Ørntoft S. Seier Poulsen E. Nexø 《Urological research》1996,24(1):15-21
Twenty-four male Wistar rats, 8 weeks old, were allocated into three groups and treated with human recombinant epidermal growth factor (EGF) administered subcutancously in doses of 0, 30, and 150 g/kg per day for 4 weeks. Blood sampling was done every 2nd week and urine sampling was done for 2 consecutive days every week. The most striking finding was that the ureters were dose dependently enlarged, due to growth of all layers of the ureteric wall. The urothelium of the bladder showed considerable hyperplasticity with a widening of the basal proliferative compartment and a normal differentiation pattern as observed by the expression of carbohydrate epitopes, characterized with lectinohistochemistry. Blood examination revealed a decrease in blood haemoglobin concentration and a slight increase in serum creatinine concentration in the high-dose group. There were no effects of EGF on the urinary excretion of electrolytes, proteins, and endogenous EGF. 相似文献
994.
Hiroyasu Ishikura Yasunari Uedono Kazunobu Yamagami Takashi Arai Naoshi Takeyama Takaya Tanaka 《Surgery today》1996,26(9):694-699
We examined the effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) and cefmetazole sodium on survival, neutrophil count, and neutrophil function in rats with peritonitis produced by cecal ligation and puncture. Rats with peritonitis received either rhG-CSF (50 or 100 g/kg) with or without cefmetazole (50 mg/kg) for 3 days, cefmetazole alone, or no treatment and were evaluated as controls. The mortality rate of all treated rats was significantly lower than that of the untreated rats. The survival rate was 57.1% for the rats given both rhG-CSF and cefmetazole, but there was no significant improvement of survival as compared with cefmetazole therapy alone. Treatment with rhG-CSF at 100 |Gmg/kg caused the circulating neutrophil count to increase significantly. The phagocytic activity for latex beads and neutrophil H2O2 production showed a greater enhancement by phorbol myristate acetate (PMA) in the untreated rats, thus indicating that neutrophils from treated rats were more activated. These findings show that rhG-CSF can improve survival and neutrophil function in rats with peritonitis, while combined therapy with cefmetazole was also found to be beneficial. 相似文献
995.
Flanagan L 《Obesity surgery》1996,6(1):38-43
Background: The cottage cheese test was developed in an attempt to find a simple way to measure functional pouch volume and
to better understand the fate of the tiny proximal pouch following the gastric bypass procedure. Methods: Our patients were
asked to eat cottage cheese in a structured fashion before their return visits from 3 months to 2 years postoperatively. Results:
We found there was a step-wise progression of increase in functional pouch volume with statistical significance between each
time interval. Also, we compared the patients' excess weight loss at 1, 2, and 3 years postoperatively to their pouch size
at 1 year postoperatively. Although there is a wide range (2.5-9.0 oz) of pouch sizes at 1 year, there is no significant difference
in excess weight loss between the smaller and larger pouches. Conclusions: The pouches enlarge by the orderly process of hyperplasia.
Within the 2.5-9 oz volume variation, the pouch volume alone is not a predictor of weight loss. Rather, how the patient uses
the pouch/tool, in addition to the other behavior modifications, determines the degree of weight loss. This data strongly
suggests that the surgeon's understanding of and teaching of the optimal use of the pouch/tool may be more important than
previously thought. 相似文献
996.
Multidisciplinary management of metastatic colorectal cancer 总被引:4,自引:0,他引:4
When colorectal cancer metastasizes to distant organs, usually multiple sites are involved and treatment consists primarily of systemic chemotherapy and supportive care. Chemotherapeutic agents effective against metastatic colorectal cancer include 5-fluorouracil, often used in combination with leucovorin or methotrexate, and irinotecan (CPT-11). Median survival with optimal chemotherapy regimens ranges from 10 to 15 months. Less frequently, colorectal cancer metastasizes only to the liver or lung. In a minority of these cases, surgical resection can be performed and results in a median survival of 28-46 months for hepatic resections and 24-25 months for pulmonary resections. Five-year survival rates range from 24 to 38% and 21 to 44% for hepatic and pulmonary resections, respectively. For isolated liver metastases that are not surgically resectable, other regional therapies that can be considered are hepatic cryosurgery, radiofrequency ablation, and hepatic arterial infusion chemotherapy. Median survival following cryosurgery is between 26 and 30 months, while median survival following radiofrequency ablation has not been established in large series. Hepatic arterial infusion chemotherapy, especially with newer combination drug regimens, may increase survival in patients with isolated liver metastases compared to systemic chemotherapy, but this must be confirmed in randomized, prospective trials. Colorectal cancer metastases to the brain can be treated with radiation therapy or surgical resection, but median survival with treatment is less than one year. 相似文献
997.
Graduated compression stockings in the prevention of deep vein thrombosis in patients with acute myocardial infarction 总被引:5,自引:0,他引:5
Venous volume (venous capacity) of the calf is low in patientswith acute myocardial infarction, who also have a high riskof deep vein thrombosis (DVT). The effect of graduated compressionstockings on the venous volume and on the incidence of DVT wastherefore studied in 80 patients aged 70 years and above withacute myocardial infarction. Graduated compression stockingswere randomly fitted to one leg, the other serving as a control,after which the venous volume was measured by strain gauge plethysmography.The incidence of DVT was measured by the 125I fibrinogen uptaketest. Venous volume was significantly higher in legs treatedwith graduated compression stockings compared to control legs.DVT developed in eight control legs but not in any leg treatedwith graduated compression stockings (P = 0.003). DVT was alsosignificantly more frequent in women compared to men and themajority of DVT developed in legs with very low venous volumevalues. 相似文献
998.
999.
Chris G. Van Nerom Guy M. Bormans Michel J. De Roo Alfons M. Verbruggen 《European journal of nuclear medicine and molecular imaging》1993,20(9):738-746
Animal studies have indicated that technetium-99m l,l-ethylenedicysteine (99mTc-l,l-EC) may be a promising tracer agent for renal function studies. We have performed a paired study with 99mTc-mercaptoacetyltriglycine (99mTc-MAG3) and 99mTc-l,l-EC in six male volunteers. In both cases, iodine-131-labelled o-iodohippurate was co-injected as an internal biological standard. The analog images between 0 and 30 min p.i. were of identical diagnostic value for both tracer agents. The two renograms were similar in all volunteers. The mean 1-h plasma clearance for 99mTc-MAG3 and 99 mTc-l,l-EC was significantly different, respectively 382.9 ± 17.1 ml/min per 1.73 m2 versus 460.2 ± 47.7 ml/min per 1.73 m2 (P<0.003). The urinary excretion after 30 min p.i. was 69.4% ± 5.6% of the injected dose for 99mTc-MAG3 versus 66.5% ± 2.5% for 99mTc-l,l-EC (P>0.05) and after 60 min p.i. respectively 83.1% ± 3.9% versus 79.8 % ± 4.3 % (P > 0.05). 99mTc-l,l-EC has a very low plasma protein binding (31% ± 6.8%) as compared to 99mTc-MAG3 (88% ± 5.2%) and a larger volume of distribution. Although the exact mechanism responsible for the high plasma clearance of 99mTc-l,l-EC is not yet fully known, we conclude that this new agent merits further clinical evaluation in patients to establish its value as a renal radiopharmaceutical.
Correspondence to: A. Verbruggen 相似文献
1000.
Chia-Hung Kao Chih-Kua Huang Shyh-Jen Wang Chung-Yuan Hsu Wan-Yu Lin Gran-Hum Chen 《European journal of nuclear medicine and molecular imaging》1993,20(8):708-711
Urease in the human gastric mucosa is a marker for infection with Helicobacter pylori (HP), an organism which is associated with peptic ulcer disease. To detect gastric urease, we examined 184 patients (144 males, 40 females; mean age: 49.8±15.6 years) with suspected peptic ulcer disease. Fasting patients were given orally 5 Ci of carbon-14 labelled urea. From each patient only one breath sample was collected in hyamine at 10 min. The amount of 14C collected at 10 min was expressed as follows: [(DPM/mmol CO2 collected)/(DPM administered)] × 100 × body weight (kg). The presence of HP colonization was determined by examination of multiple endoscopic prepyloric antral biopsy specimens subjected to culture or a rapid urease test. For the purpose of this study, HP-positive patients were defined as those with characteristic bacteria as indicated by a positive result of either the culture or the rapid urease test; HP-negative patients were defined as those with negative findings on both the culture and the rapid urease test. Of the 184 cases, 99 (53.8%) were positive for HP infection, and 85 (46.2%), negative. The sensitivity and specificity of the rapid 10 min 14C-urea breath test for the diagnosis of HP-associated peptic ulcer disease were evaluated by a receiver operating characteristic (ROC) curve with a variable cut-off value from 1.5 to 4.5. When a cut-off value of 1.5 was selected, the sensitivity was 100% and the specificity, 83.5%; when a cut-off value of 4.5 was selected, the sensitivity was 54.5% and the specificity, 97.6%.
Correspondence to: Chia-Hung Kao 相似文献