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61.
Hypolaetin-8-glucoside, a flavonoid isolated from SIDERITIS MUGRONENSIS possessing anti-inflammatory activity inhibited dose-dependently the human PRP aggregation induced by ADP with a IC (50) = 2.4 x 10 (-4) M. This action does not seem to be related to cyclo-oxygenase, as this flavonoid is not an inhibitor and even is able to act as a cofactor for this enzyme.  相似文献   
62.
Examination of the input-output events in functioning organs by the use of the impulse-response function (IRF) for a radioactive tracer is gaining more and more ground in nuclear medicine. This study summarizes the development of deconvolution analysis, laying special stress on the model-free approach. System linearity and time invariance are discussed, and means of eliminating noise in IRFs originating from the input and organ-time-activity curves are outlined. Typical IRFs are illustrated by flow diagrams, time-domain curves, and their representation by Laplace transforms. The cases of nondiffusible and diffusible tracers as well as parenchymally extracted and transported substances are discussed. Methods for the derivation of models and for the calculation of physiologically important parameters from theIRFs are suggested.At present, a guest scientist at the Institute for Medicine, Nuclear Research Center Jülich, Jülich, Federal Republic of Germany  相似文献   
63.
Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent.  相似文献   
64.
We report two patients with coarctation of the aorta who were admitted to the hospital with ruptured cerebral artery aneurysms. In both patients, we surgically treated the coarctation and later repaired the intracranial lesion. One patient, a 34-year-old woman, is alive and well after 3 years; whereas, the other, a 19-year-old man, did not survive. We discuss the sequence for surgery, which continues to be subjected to debate.  相似文献   
65.
Rhabdomyosarcoma (RMS) is a common malignancy in children, but embryonal rhabdomyosarcoma (ERMS) deposits rarely occur in the breast in adults. Therefore, little is known about magnetic resonance imaging (MRI) features of breast metastases from RMS, especially the embryonal type. We reported a case of a 22-year-old woman who was diagnosed with ERMS at left foot 2 years ago and accepted operation and chemotherapy. She was confirmed to have breast metastases from the left foot. Successive imaging examinations were performed 3 months apart. Breast ultrasound indicated a benign lesion, and further examination did not reveal any bone metastases. However, predominant restricted diffusion and rim contrast enhancement on MRI combined with the patient's medical history suggested a malignancy of BI-RADS 5. After 3 months, breast ultrasound revealed masses detected last time became larger and lobulated. In addition, internal heterogeneous intensity and rim contrast enhancement with restricted diffusion were revealed on MRI. We speculated that typical MRI findings of breast metastases from RMS may include iso- to hypointensity on T1WI, heterogeneous hyperintensity on T2WI, and circular enhancement with restricted diffusion. Moreover, mild peritumoral edema, rapid expansion of necrosis, and ascending time-intensity curve detected on MRI may be features of the ERMS type.  相似文献   
66.
The inhibitory activity of different components from Candida albicans membrane protoplasts against clotrimazole and eberconazole was studied. The phospholipid fraction had the most inhibitory activity and the antimycotic activity of eberconazole was more affected than that of clotrimazole.  相似文献   
67.
The neuroprotective efficacy of the most potent competitive α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) antagonist 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(F)quinoxaline (NBQX) and three recently developed 2,3-benzodiazepine non-competitive AMPA antagonists (GYKI 52466, 53405 and 53655) was investigated in primary cultures of rat telencephalic neurons. NBQX protected cultured neurons against AMPA (20 μM for 21-23 h) induced toxicity with EC(50) of 0.5 μM. In the same test GYKI 52466, 53405 and 53655 had EC(50) values of 10.6, 9.3 and 5.1 μM, respectively. Thus we found the competitive antagonist NBQX to be ten times more effective neuroprotectant in vitro than the most potent non-competitive GYKI compound (GYKI 53655).  相似文献   
68.
Our examinations were finished on 80 patients with different dementia forms. We specified the concentration of liquor immunoglobulins with the nephelometrical method, and concluded the presence of intrathecal immunoglobulin (IgG, IgM and IgA) synthesis on the basis of the Link index. In the cases of senile dementia, SDAT and AD, we found altered blood-brain barrier function. We detected intrathecal IgG and IgA synthesis at AD patients, while the synthesis of all the three immunoglobulins was characteristic for the Jakob-Creutzfeld disease. On the basis of our results, we came to the conclusion that, at the different dementias, the immunopathological occurrences play different roles in the development of the disease.  相似文献   
69.
The Morgagni hernia occurs behind the sternum and is a rare diaphragmatic defect although the late diagnosis may result in important clinic symptoms and poor prognosis. The authors present a case report of a child with 11 months and respiratory symptoms with chronic pulmonary infections and several hospitalizations without etiologic diagnosis. The conclusion was for the early Morgagni hernia diagnosis and the prevention of chronic complications.  相似文献   
70.
Objective. The objective of our study was to determine if clinical observation of pressure-flow relationships (PFR) can differentiate between partial external obstruction (obstruction) and infiltration as a cause of poor performance of gravity-fed infusions.Methods. A total of 24 patients with functional intravenous cannulae in situ had obstruction simulated by the application of a tourniquet proximal to the cannula. The change in flow (F) for a discrete change in pressure (P) was determined in each case by counting drop rates at two different elevations of the fluid reservoir level, 10 cm apart. The same process was repeated in 15 patients in whom the cannula was in an extra vascular location (infiltration). Three sizes of cannula—16-gauge, 18-gauge, and 20-gauge—were examined, with equal distribution of sizes in each group. The effect on flow rates of inflating a blood pressure (BP) cuff proximally on the cannulated limb was assessed. The ratio P/F is the total resistance of the infusion system, and by subtracting known values for resistance of infusion tubing and cannula, the venous or tissue resistance was calculated.Results. There was a statistically significant difference between the change in flow for obstructed compared with infiltrated cannulae for the same change in pressure for each cannula size. The mean venous resistance was 23 mm Hg/L/hr, while that of tissue was 280 mm Hg/L/hr, with no overlap between groups. There was no effect on flow rate with blood pressure cuff inflation in the infiltrated group whereas flow progressively fell in the obstructed group.Conclusions. Clinical observation of PFRs in poorly functioning gravity-fed IV infusions can assist in detecting infiltration as a cause. Inflation of a blood pressure cuff will further impair flow where the cannula is intravascular, but will have no effect in an extravascular location.  相似文献   
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