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991.
BACKGROUND AND PURPOSETo detect areas of cerebral perfusion from bypass arteries after vascular reconstruction, we administered selective intraarterial microsphere tracer into the external carotid arteries and determined (via single-photon emission computed tomography [IA-SPECT]) whether the distribution of radiotracer matched the arteriographic distribution of contrast material as shown on external carotid angiograms.METHODSWe compared the extent of regional distribution of tracer after external carotid artery injection of 20 to 40 MBq of 99mTc-HMPAO or 99mTc-ECD with that of contrast medium on the external carotid angiograms in 582 cortical regions in 12 patients with atherosclerotic occlusive disease and in 18 patients with moyamoya disease.RESULTSMarked accumulation of tracer was found only in the expected, specific, newly developed areas of cerebral perfusion from bypass arteries. The regional distribution of tracer corresponded to that of contrast medium in 523 regions (90%) and did not correspond in 59 regions (10%). Significant overestimation of the distribution of contrast material relative to that of tracer was observed in the patients with moyamoya disease.CONCLUSIONSPECT showed slightly different distribution of tracer from that predicted by conventional angiography. IA-SPECT should enhance the analysis of newly developed areas of cerebral perfusion from the bypass arteries.  相似文献   
992.
Measurements were made of glutathione (GSH) levels, catalase activity and the oxidant sensitivity of the erythrocytes from the koala (Phascolarctos cinereus) and the common brushtail possum (Trichosurus vulpecula). The oxidant sensitivity was tested by treating the haemolysates with either 0.55 him H2O2 or 1.4mm NaNO2. The erythrocytes of the koala had greater levels of GSH and catalase and yet were found to be more susceptible to oxidation induced by both these oxidants.  相似文献   
993.
Osteoclastogenesis inhibitory factor (OCIF) is a novel secreted protein that inhibits osteoclastogenesis both in vitro and in vivo. In this study, we examined the effects of OCIF on serum calcium (Ca) concentrations in normal mice and in hypercalcemic nude mice carrying tumors associated with humoral hypercalcemia of malignancy. In normal mice, a single intraperitoneal injection of OCIF reduced serum Ca levels in a dose-dependent manner. Significant decrease in serum Ca (by 1.6 ± 0.3 mg/dL, n = 5) was observed 2 h after the injection of OCIF at 20 mg/kg and the hypocalcemic effect continued for up to 12 h. Serum phosphate (Pi) concentrations also decreased in response to OCIF. Urinary excretion of Ca, Pi, and creatinine did not change significantly after injection of OCIF or vehicle. In hypercalcemic, tumor-bearing nude mice, a single intraperitoneal injection of OCIF at 20 mg/kg resulted in a dramatic decrease in serum Ca (maximal decrease 2.8 ± 0.37 mg/dL, n = 11), which continued for up to 24 h. The results suggest that OCIF decreased serum Ca through its inhibitory effect on bone resorption. Furthermore, it is suggested that OCIF has therapeutic potential for the treatment of hypercalcemic conditions such as malignancy-associated hypercalcemia.  相似文献   
994.
Parker  Lisa S. 《JAMA》1998,280(20):1798-1799
  相似文献   
995.
We prospectively enrolled 160 consecutive patients with inversion trauma of the ankle in a diagnostic protocol that included physical examination within 2 days and at 5 days after trauma, arthrography, stress radiography, and ultrasonography. 135 patients had pathological lateral ligament laxity on the later physical examination or lateral ligament rupture diagnosed on arthrography and they were operated on. 122 of these patients had ligament ruptures.

At clinical follow-up after a minimum of half a year, all of the patients who were not operated on had stable joints without signs of previous ligament ruptures.

Delayed physical examination at 5 days after the injury led to the highest overall sensitivity (96%) and specificity (84%) for the detection of a ligament rupture. Additional diagnostic procedures, at a considerable cost, yielded little additional information.  相似文献   
996.
997.
BACKGROUND: Catheter hub contamination is being increasingly recognized as a source of catheter-related sepsis. The authors have investigated the efficacy of a new hub design in preventing endoluminal catheter contamination and catheter-related sepsis arising at the hub. METHODS: Adult surgical and intensive care patients requiring a subclavian catheter for at least 1 week were randomly assigned to receive catheters with standard connectors (control group, n=73) or equipped with a new hub model (new hub group, n=78). Skin, catheter tip, and hub cultures were performed at the time the catheter was withdrawn because therapy was terminated or because of suspicion of sepsis, in which case peripheral blood cultures were taken. RESULTS: Of the 151 patients included, 15 (10%) developed catheter-related sepsis. Catheters were more often withdrawn because suspicion of infection in the control group (42 vs. 19%, p<0.005). Catheter sepsis rate was higher in the control group (16 vs. 4%, p<0.01) because of the low rate of catheter sepsis arising at the hub observed in the new hub group (1 vs. 11%, p<0.01). The prevalence of culture-positive catheter hubs without associated bacteremia (colonization) was higher in the control group (18 vs. 5%, P<0.03). CONCLUSIONS: A new catheter hub has proved to be useful in preventing endoluminal bacterial colonization and catheter-related sepsis in subclavian lines inserted for a mean of 2 weeks.  相似文献   
998.
前路器械内固定手术矫治脊椎侧凸   总被引:5,自引:2,他引:3  
作者从1979年开始使用戴瓦氏手术,1983年开始使用斯伍基氏手术,至1994年共做57例(男性28例,女性29例),年龄为9~28岁。手术无死亡。术后并发症戴瓦氏手术:1例截瘫,2例椎体骨折伴螺丝钉拔出,2例螺丝钉折断,2例金属缆折断;斯伍基氏手术,1例杆折断,2例切口感染。  相似文献   
999.
1000.
Image-directed color Doppler ultrasonography (ICDUS) studies of 86 patients with superficial solid masses yielded significantly lower resistive index (RI) values in acute inflammatory lesions, but no significant difference between the maximum systolic flow velocities (S) of the patient groups with malignant, benign, and acute inflammatory lesions. When analyzed separately, the malignant soft-tissue tumor subgroup was shown to have significantly higher mean RI compared to that of the malignant node subgroup. We conclude that RI may be useful in the differentiation of acute inflammatory masses from other pathological entities. Malignant soft-tissue tumors, especially sarcomas, may have different Doppler features from those of carcinomatous tumors. © 1995 John Wiley & Sons, Inc.  相似文献   
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