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排序方式: 共有364条查询结果,搜索用时 15 毫秒
81.
刺果甘草化学成分的研究 总被引:5,自引:0,他引:5
从刺果甘草(Glycyrrhiza pallidiflora Maxim)的根和根茎中分离到五种化合物,经理化性质和光谱方法鉴定,化合物P-2为4-羟基-2,4’-二甲氧基查尔酮,为一新的化合物,命名为刺果甘草查尔酮(glypallichalcone,P-2)。其它分别为4'-O-methyl-coumestrol(P-1),谷氨酸乙酰化物(N-acetylglutamicacid,P-3)和芒柄花素(formononetin,P-4),均为首次从该植物中获得。此外还得到β-谷甾醇(β-sitos-terol,P-5) 相似文献
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84.
Ahn JM; Kwak SM; Kang HS; Muhle C; Pedowitz RA; Frank LR; Trudell D; Haghighi P; Resnick D 《Radiology》1998,208(1):57
85.
Complications of automatic implantable cardioverter defibrillators: radiographic, CT, and echocardiographic evaluation 总被引:1,自引:0,他引:1
Goodman LR; Almassi GH; Troup PJ; Gurney JW; Veseth-Rogers J; Chapman PD; Wetherbee JN 《Radiology》1989,170(2):447-452
Automatic implantable cardioverter defibrillators (AICDs) were studied in three groups: (a) Serial radiographs were reviewed in 51 clinic patients. Twenty of 96 (21%) AICD patches distorted with time. (b) Thirty-six postoperative computed tomographic (CT) scans of asymptomatic patients revealed that pericardial fluid collections were frequent during the month after surgery but rare beyond that. Echocardiography was insensitive for these collections. CT also demonstrated dense fibrosis around some distorted patches, months after surgery. (c) Five other patients with pericardial infection had distorted patches, and the four studied with CT had fluid beneath their patches. (d) A case of constrictive pericarditis had distorted patches but was not diagnosed with CT. The authors conclude that distorted patches may indicate postoperative complications and that CT is the imaging modality of choice. 相似文献
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87.
Meuli RA; Wedeen VJ; Geller SC; Edelman RR; Frank LR; Brady TJ; Rosen BR 《Radiology》1986,159(2):411-418
We report the first clinical experience with a new method for projective imaging of blood vessels (angiography) using magnetic resonance. Vascular contrast is produced noninvasively by the phase response of moving protons. Diastolic and systolic gated images produce, respectively, flow signal and flow void; the difference image is a map of the pulsatile flow: an arteriogram. Preliminary studies are presented of the lower extremities of one healthy volunteer and four patients (one each with occlusive disease, soft-tissue tumor, arteriovenous malformation, and venous femoral-popliteal graft). Patient data are compared with accompanying conventional arteriograms, and the new method is discussed. 相似文献
88.
OBJECTIVE: The objective of this study was to compare the cost (measured as resource utilization by the institution) and clinical effectiveness of transcatheter coil occlusion and surgical patent ductus arteriosus (PDA) closure. Similar comparisons have been made previously with other devices no longer in use in the United States. No such comparison has been made for coil occlusion, which has been performed increasingly since 1992. METHODS: All patients who underwent either coil or surgical closure of uncomplicated PDA at our institution between August 1993 and June 1996 were retrospectively identified. Patients were included in the study if they were eligible for either closure technique. Thus, they had a restrictive PDA (not associated with pulmonary hypertension) and no overt evidence of congestive heart failure. Patients were excluded if they had other significant cardiac or noncardiac problems. Total procedural and recovery costs (including labor, material, equipment, and overhead) incurred by the provider were determined using a cost accounting system called Transition Systems, Inc. To define further how costs differed for the two techniques, total costs were subdivided into the categories of professional, technical, inpatient hospital stay, postprocedure testing, and supplies and other miscellaneous costs. PDA closure rates and associated complications also were compared. Follow-up information was sought from outpatient visits to our institution or by contacting the referring physicians. RESULTS: A total of 39 patients were identified, 3 of whom were excluded because of coexisting medical problems. The study group consisted of 36 patients; 24 underwent PDA coil occlusion and 12 surgical closure. Mean age and weight were 8.8 years and 28.5 kg for the coil patients, and 7.3 years and 32.8 kg for the surgical patients. Median procedural duration was 150 minutes for the coil group and 165 minutes for the surgical group. The total cost to the institution of coil occlusion was significantly lower than that of surgical closure ($5273 vs $8509). The largest difference lay in the cost of hospital stay ($398 vs $2566) and in the professional costs ($1506 vs $2782). Technical costs were similar ($2156 for coil, $2151 for surgery), although use of the catheterization laboratory per unit of time was more expensive than use of the operating room ($800 vs $400 per hour). Additional technical costs of the surgical procedure related to general anesthesia and postoperative care made up the difference. No patient in either group had a residual PDA murmur at hospital discharge or thereafter. Follow-up echocardiography was performed in all coil occlusion patients, and tiny residual leaks were detected in 17%. Only 42% of the surgical patients had postoperative echocardiography; none had residual leaks. There were no deaths or major complications in either group. CONCLUSIONS: Transcatheter coil occlusion is as effective and less costly than surgical closure if silent residual leaks are not considered clinically significant. This information may be used increasingly in patient care decisions in the current era of managed medical care. 相似文献
89.
Traumatic brain stem injury: MR imaging 总被引:9,自引:0,他引:9
Eighty-seven patients with acute (n = 70) or chronic (n = 17) head injuries were prospectively studied with magnetic resonance (MR) imaging and computed tomography (CT) to characterize the frequency and nature of traumatic brain stem injury (BSI). Forty-eight traumatic lesions were identified in 36 patients. Of 36 patients, 35 had neurologic findings that corroborated the radiographic impression of BSI. T1- and T2-weighted MR images demonstrated a significantly higher number of lesions than did CT. Patients with BSI had a significantly higher frequency of corpus callosum and diffuse axonal "shear" lesions. The number of cortical contusions and extraaxial hematomas was similar in both groups. The mean Glasgow Coma Scale (GCS) scores at admission were significantly lower in patients with evidence of BSI on MR images. Patients with primary BSI had lower initial GCS scores, a longer duration of coma, more diffuse axonal "shear" lesions, and a higher frequency of corpus callosum injury than patients with secondary BSI. The location of primary and secondary lesions was significantly different. Overall, MR imaging was more helpful than CT in detecting, localizing, and characterizing BSI. 相似文献
90.
SSS Guirado JS Conejo-Mir MA Muñoz JB Wite LR Fernandez-Freire JV Ortíz 《Journal of the European Academy of Dermatology and Venereology》2007,21(1):100-103
BACKGROUND: Sitosterolaemia is a lipid disorder in which plasma plant sterol levels are extremely elevated. Sitosterolaemia is clinically characterized by tuberous and tendon xanthomas, premature vascular disease and arthritis. OBJECTIVE: To report a case of sitosterolaemia diagnosed by cutaneous manifestations and to review this rare disease. METHODS: We report the case of a 60-year-old woman who presented with cutaneous xanthomas, arterial hypertension and polyarthralgias. The patient had had hypercholesterolaemia for many years without reduction of serum cholesterol, despite treatment with fenofibrate. RESULTS: Ezetimibe therapy was started, decreasing sitosterol plasmatic levels and tuberous xanthomas after 3 months of treatment. CONCLUSION: It is important to detect levels of sitosterol in plasma in patients with premature vascular disease, presence of xanthomas, and uncontrolled hypercholesterolaemia. Ezetimibe therapy is effective. 相似文献