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991.
W T Yuh E T Tali H D Nguyen T M Simonson N A Mayr D J Fisher 《AJNR. American journal of neuroradiology》1995,16(2):373
PURPOSETo evaluate the effect of MR contrast dose versus delayed imaging time on the detection of metastatic brain lesions based on lesion size.METHODSContrast MR examinations with gadoteridol were obtained in 45 patients with brain metastases. The patients were divided into two groups: 16 received cumulative standard dose (0.1 mmol/kg) and 29 received cumulative triple dose (0.3 mmol/kg). Both groups were evaluated at two dose levels (lower dose and higher dose) with two separate injections. Each patient received an initial bolus injection of either 0.05 (cumulative standard dose) or 0.1 (cumulative triple dose) mmol/kg of gadoteridol to reach the lower-dose level and underwent imaging immediately and 10 and 20 minutes later. Thirty minutes after injection, an additional bolus injection of 0.05 (cumulative standard dose) or 0.2 (cumulative triple dose) mmol/kg was administered to reach the cumulative higher-dose level (cumulative standard dose, 0.1 mmol/kg; cumulative triple dose, 0.3 mmol). Images were acquired immediately.RESULTSThere was no difference in the detection rate for lesions larger than 10 mm among T2-weighted, lower-dose immediate and delayed, or immediate higher-dose images in both study groups. Lesions smaller than 10 mm had improved detection with delayed imaging in both study groups; however, the immediate higher-dose studies still had the highest detection rate.CONCLUSIONIn the evaluation of small central nervous system metastases, either delayed imaging after the injection of standard contrast dose or higher contrast dose may improve their detection, and therefore affect clinical management. Higher contrast dose (cumulative triple dose) studies appear to be more effective than delayed imaging with standard dose. 相似文献
992.
D. N. K. Sarma R. L. Khosa J. P. N. Chansauria M. Sahai 《Phytotherapy research : PTR》1995,9(8):589-590
The ethanol extracts of the roots of T. cordifolia Miers and C. asiatica Linn were observed to induce a marked protective action against an 8 h restraint stress induced ulcerization, the activity being comparable to that of diazepam. 相似文献
993.
C R Evian C B Ijsselmuiden G N Padayachee H S Hurwitz 《Suid-Afrikaanse tydskrif vir geneeskunde》1990,78(9):517-520
In January 1989, the Johannesburg City Health Department developed an AIDS education poster. The poster was adapted from a cartoon in the Sowetan newspaper and was formally evaluated before its final production. As a result of this evaluation further editing and restructuring of the poster proved necessary. The methodology used in the evaluation is outlined, and some of the findings that emerged during the evaluation are discussed, since few formal evaluations of health education material seem to have been documented in South Africa. This study highlights the importance of formative evaluation of printed health educational media by a sample of the target audience before production and distribution. 相似文献
994.
N M Delgado R Reyes A Carranco L Huacuja H Merchant A Rosado 《Archives of andrology》1990,25(2):121-129
The effect of specific glycosaminoglycan-hydrolyzing enzymes on the ruthenium red staining of pig spermatozoa was studied. Washed spermatozoa were incubated at 35 degrees C in buffer or with neuraminidase 0.5 units/ml, heparinase 0.2 mg/ml, or chondroitinase ABC 2.0 units/ml. After incubation sperm cells were washed, stained with ruthenium red and studied under the electron microscope. Anionic sites in the surface of untreated spermatozoa follow regularly the plasma membrane, but present are numerous processes constituting what has been defined as the glycocalyx. Neuraminidase did not affect the distribution of ruthenium red on the surface of the spermatozoa, but eliminated almost completely the processes of the glycocalyx. Heparinase caused loss of the ruthenium red-stained sites on the membrane surface of pig spermatozoa with less influence on the dense processes of the glycocalyx. A similar loss of ruthenium red-stained sites was observed with nitrous acid treatment. A striking effect of treatment with chondroitinase ABC was the production of a typical acrosome reaction. 相似文献
995.
We report 2 cases of leiomyosarcoma of the bladder that occurred after long-term cyclophosphamide chemotherapy for lupus nephritis and rheumatoid arthritis. One patient had a tumor at the end of an 11-year course of chemotherapy and 1 approximately 7 years after completing a 7-year course of chemotherapy. Patient 1 underwent left partial cystectomy and patient 2 underwent cystectomy with ileal conduit urinary diversion. In patient 1 the tumor was a typical leiomyosarcoma and patient 2 had a myxoid variant. Both patients were free of disease at 4 months and 3 years, respectively. Whereas previous reports of the carcinogenic effects of cyclophosphamide have been questioned, since the induced tumors occurred in patients being treated for other neoplasms (lymphoproliferative and myeloproliferative disorders), the disease in both of our patients followed cyclophosphamide therapy for nonneoplastic disorders. 相似文献
996.
Involvement of platelet activating factor and thromboxane A2 in the renal response to unilateral ureteral obstruction 总被引:1,自引:0,他引:1
Platelet activating factor (PAF) and thromboxane A2 (TxA2) are two vasoactive mediators which can decrease renal blood flow. Both are synthesized by various intrarenal cell types or by macrophages which may infiltrate the kidney during unilateral ureteral obstruction (UUO). In several experimental systems, PAF receptor activation is accompanied by TxA2 release; pharmacological modification of TxA2 synthesis or receptor activation modulates the response to PAF. The involvement of PAF in UUO has not been studied previously, and the role of TxA2 has not been clearly defined by previous investigations. The hemodynamic response to acute UUO is characterized by decreases in renal blood flow (RBF) and glomerular filtration rate and an acute increase in ureteral pressure. In the present experiments, the involvement of either PAF or TxA2 in the acute response to UUO was studied by determining if blockade of either the TxA2 or PAF receptor would affect the renal hemodynamic response to UUO. In addition, the effect of blockade of the TxA2 receptor on the renal response to PAF was determined. Our results indicate that only a small portion of the renal response to PAF is mediated by TxA2, and that neither PAF nor TxA2 can be implicated in the acute hemodynamic response to UUO. TxA2 or PAF involvement in the chronic response to UUO still remains to be determined. 相似文献
997.
The article deals with the frequency of isolation of non-fermentative gram-negative bacteria, potential causative agents of postoperative infection, from objects found in the environment of various departments of a surgical inpatient clinic. The species composition of the grown culture was determined. The relation of the isolation rate of certain species of nonfermentative bacteria to the object of the examination, the department of the clinic, and the disinfection method applied was revealed. The authors point out that it is necessary to undertake systematically the investigations to determine of the activity of antiseptics and disinfectants in relation to the microorganisms indicated in order to choose the effective methods for the prevention of postoperative infection induced by nonfermentative bacteria. 相似文献
998.
From study of data on 5- and 10-year survivals of 560 patients who underwent operation for breast cancer in stage T1.2NoMo, the authors determined the most significant prognostic factors. These were the histological form of the tumor and the degree of invasion into the adjoining tissues. The percentage of each studied factor was determined by mathematical analysis, which allowed the individual prognosis for each patient to be made and treatment planned accordingly. 相似文献
999.
Addition of immunomodulating therapy with Thymalin, a thymus agent, to the multimodality therapy of burnt patients contributes to a rapid normalization of immunological parameters. The most marked immune response was observed 7-10 days after a therapy course initiated in the early periods of burn disease in patients with severely depressed T-system immunity and a high sensitivity to the drug. Inclusion of a donor blood leukomass transfusion course activates the cellular link of the immune system just after the treatment course, but fails to favour a stable normalization of thymus-dependent lymphocyte ratios. 相似文献
1000.
The frequency of the development of rejection crises in the early postoperative period in 32 recipients of allogeneic kidneys from alive related donors was analysed depending on the histocompatibility according to the antigens of the HLA-AB system and the nature of the immunosuppressant therapy. The results of the analysis showed that the frequency of rejection crises was 100% when the donor and recipient were compatible in 1-2 antigens, and 40% in compatibility according to 3-4 antigens. The incidence of rejection crises was 71.4% among patients who received the standard immunosuppressant therapy (corticosteroids + azathioprine) and 36% among those given also sandimmune. Analysis of the frequency of rejection crises according to the ABO blood group system to which the donor-recipient pair occurred, showed that rejection crises occurred most frequently among patients with A (II) blood group. 相似文献