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71.
The authors describe the technique of RARE sequences (Hennig, 1986) and their hydrographic application to urinary imaging, RARE urography. Heavily T2-weighted non-tomographic images of the urinary tract are obtained in less than 30 seconds, without contrast medium or ionizing radiation. The whole urinary tract is visualised on one image with a spatial resolution superior to that of sonography. The semiology of RARE urography is similar to that of the intravenous pyelogram. Silent kidneys are also visualised. 相似文献
72.
Approximately 25% of breast cancers occur in premenopausal women. In addition to local therapy, surgery or surgery plus irradiation, systemic chemotherapy administration has become the standard of care for all node-positive and many node-negative patients. Systemic adjuvant chemotherapy can result in ovarian dysfunction or failure. This renders many women prematurely estrogen deficient. The consequences of menopause, genitourinary atrophy, bone loss, and increased risk of cardiovascular disease, have not been routinely assessed in clinical trials. The risks of estrogen deficiency have not been assessed in comparison to improved disease-free and overall survival benefits of adjuvantly treated premenopausal breast cancer patients. Estrogen-replacement therapy in postmenopausal women has been shown to prevent osteoporosis and reduce fracture risk. The majority of studies also show a marked reduction in cardiovascular disease and mortality. Estrogen-replacement therapy has been considered a disease-prevention strategy rather than a therapeutic intervention. The risks and benefits of estrogen-replacement therapy in women with primary breast cancer are unknown. It is unknown how the well-known benefits accrued from reduction in skeletal and cardiovascular morbidity/mortality compare with the potential risks of increased breast cancer morbidity/mortality. Carefully designed prospective clinical trials with well-defined objectives and endpoints are required to learn if more harm than good is done by the withholding of estrogen therapy in breast cancer patients. 相似文献
73.
RV Lebo ED Lynch MS Golbus RR Flandermeyer PH Yen LJ Shapiro 《Canadian Metallurgical Quarterly》1993,46(6):652-658
X-linked ichthyosis results from steroid sulfatase (STS) deficiency; 90% of affected patients have a complete deletion of the entire 146 kb STS gene on the distal X chromosome short arm (Xp22.3). In these families prenatal diagnosis and carrier testing can be completed in 2 days by hybridizing simultaneously 2 different cosmid probes labeled with fluorescein or Texas red and counterstaining interphase nuclear DNA with DAPI. An STS gene probe labeled with Texas red hybridizes specifically to the steroid sulfatase gene on the X chromosome. A second flanking probe labeled with fluorescein hybridizes to both the normal Y chromosome and normal and STS deleted X chromosomes. In this fashion the interphase nuclei of normal males, affected males, normal females, and carrier females can be distinguished unambiguously. Because normal males and carrier females each show two yellow-green fluorescein spots and one Texas red STS spot, use of this test prenatally requires determining fetal sex independently with repetitive X and Y chromosome-specific probes. This procedure can be used with lymphocytes, direct and cultured chorionic villus cells, direct and cultured amniocytes, and fibroblasts. Similar methods are anticipated to be useful for rapid diagnostic assessment of other aneuploid gene disorders. 相似文献
74.
75.
Presentation of one case of bladder carcinoma which caused acute abdomen following spontaneous perforation. This presentation is extremely rare and should be taken into account when haematuria and abdominal pain appear simultaneously. 相似文献
76.
In man, the rate of resting salivary secretion can be influenced by environmental stimuli related to light dark cycles or by noxious stimuli (stressors) of psychological origin. The sympathetic branch of the autonomic nervous system and the adrenal medulla play an important part in homeostatic responses. Previous observations have shown that chronic exposure of rats to constant light promotes degranulation of parotid acini and desensitization of submandibular beta-adrenergic receptors. Now the submandibular secretory response elicited by beta- and alpha2-adrenergic agonists was studied in rats chronically exposed to environmental conditions that modified the activities of sympathetic efferents to the pineal, salivary and adrenal glands. Adult male rats were exposed to constant light (LL) or constant darkness (DD) for 20 days, or to stress (2 h daily immobilization) for 14 days. Control animals were kept under the usual lighting conditions and without immobilization. Dose response curves to isoproterenol (i.v), before and after administration (i.v.) of a dose (20 microg/kg) of clonidine were obtained. Beta-adrenergic desensitization was observed in all the experimental groups, while alpha2-adrenergic desensitization was only observed in the stress and LL groups. The results suggest that circulating catecholamines could mediate light and stress effects on submandibular beta-adrenergic secretory responses. Extrasynaptic alpha2-adrenoceptors might modulate the submandibular secretory response when predictable environmental stimuli (daily light phase) or unpredictable stressors raise the concentrations of circulating catecholamines. 相似文献
77.
RV Thakker 《Canadian Metallurgical Quarterly》1998,1448(2):166-170
From 1990 to 1995, 12 patients with cavo-atrial renal cell carcinoma underwent resection of the tumor. Circulatory arrest was employed in 11/12 cases. The neoplasm extended to the inferior vena cava in two patients and to the intrahepatic veins or right atrium in five cases. Two severely cardiac compromised patients died perioperatively. Of five patients who showed preoperative suspicion of isolated metastases, 3 patients died postoperatively because of relapsing disease after a mean period of 10.8 months. Five patients are alive and doing well after a mean follow-up of 14.8 months. In our experience myocardial dysfunction determined poor immediate survival. Mid-term survival was influenced by preoperative metastases and lymph-node involvement, but not by intracaval extension. Circulatory arrest appears to be a relatively safe technique to remove renal carcinoma with cavo-atrial extension and should be indicated whenever there are no metastases. 相似文献
78.
RV DaSilva 《Canadian Metallurgical Quarterly》1996,18(6):1374-1382
This paper provides an overview of how one pharmacy benefits manager, MedImpact Pharmaceutical Management, Inc. (San Diego, California), approaches its disease management (DM) program for asthma. This group's experience with DM counters the common but fallacious belief that reduction of component costs leads to reduction of total expenditures. In fact, greater expenditures on certain components (in particular, drug therapies and preventive and follow-up visits to physicians) can result in greatly reduced overall expenditures by reducing hospitalizations and emergency department treatments for asthmatic patients. The program addresses four essential components of DM: physician intervention, patient empowerment, health risk management, and pharmaceutical care. For each of these areas, careful statistical analysis, effective education, and integrated management can help improve patient care while reducing overall costs. 相似文献
79.
RV Tupitsina 《Canadian Metallurgical Quarterly》1976,21(6):44-47
The experiments on mice of line SHR have shown that in animals, delivered by Cesarean section I hour following intrauterine injection of 40 mg/Kg of DMBA in mothers (a period of maximum concentration of the carcinogen in the tissues of foetuses) and sacrificed one year later, carcinogenesis proceeded much more intensively than in mice, which after transplacental DMBA exposure continued their intrauterine development for 6 hours longer, i.e. till complete disintegration of DMBA. An enhancement of the transplacental carcinogenic effect was manifested in a reliable increase of the total frequency of the appearance of different neoplasms, in more frequent development of lung, ovary and mammary tumors, and also in the appearance of malignant lung tumors-adenocarcinomas. A considerable enhancement of the transplacental blastomogenic effect in these mice was due to exclusion of the detoxication function of the maternal organism. 相似文献
80.