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91.
Human lymphocytes and Chinese hamster ovary (CHO) cells in culture were exposed for 12 1/2 hours to a magnetic resonance imaging apparatus with a 2.35-Tesla magnet and 100-MHz radio frequency emission. The cells were examined for cytogenetic damage manifested either as chromosome aberrations or sister chromatid exchanges (SCEs), which constitute very sensitive measures of genetic and cellular damage. In either unstimulated or stimulated human lymphocytes, as well as in exponentially growing CHO cells, no increase in either chromosome aberrations or SCEs was found as a result of exposure to these MR conditions. The data indicate that long-term exposure to MR imaging conditions far exceeding those to be found in the clinical situation does not cause cytogenetic damage.  相似文献   
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The Mark IV system for radionuclide computed tomography of the brain   总被引:5,自引:0,他引:5  
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95.
An unusual family is described with a congenital bleeding disorder present in four males belonging to three generations. Of the three surviving affected males, all had splenomegaly and petechiae. The three had moderate thrombocytopenia (55-90 X 10(9)/liter) and markedly prolonged Ivy-template bleeding times (greater than 30 min). They were also noted to have reticulocytosis and, upon further investigation, imbalanced globin chain synthesis resembling that of beta-thalassemia minor. Studies on nine additional family members in four generations were normal except for slight elevations of reticulocyte counts in female members, one of whom had the abnormal globin chain synthesis ratio. In male members, the bleeding tendency and clinical signs always occurred in the presence of the globin chain synthesis defect and reticulocytosis. This previously undescribed condition was apparently transmitted as an X-linked disorder.  相似文献   
96.
The effect of fenugreek seeds (Trigonella foenum graecum) on blood glucose and the serum lipid profile was evaluated in insulin-dependent (Type I) diabetic patients. Isocaloric diets with and without fenugreek were each given randomly for 10 d. Defatted fenugreek seed powder (100 g), divided into two equal doses, was incorporated into the diet and served during lunch and dinner. The fenugreek diet significantly reduced fasting blood sugar and improved the glucose tolerance test. There was a 54 per cent reduction in 24-h urinary glucose excretion. Serum total cholesterol, LDL and VLDL cholesterol and triglycerides were also significantly reduced. The HDL cholesterol fraction, however, remained unchanged. These results indicate the usefulness of fenugreek seeds in the management of diabetes.  相似文献   
97.
Chemokine expression and leucocyte infiltration in Sjogren's syndrome   总被引:3,自引:0,他引:3  
OBJECTIVE: To investigate the expression and source of chemokines in minor salivary gland biopsies (MSGs) in patients with Sjogren's syndrome (SS). METHODS: Immunohistochemical analysis was used to determine the pattern of chemokine expression in MSGs from patients with (n=6) and without (n=5) SS, as well as to examine the phenotype of both resident and infiltrating cells expressing chemokines. RESULTS: Significant differences in the number of infiltrating mononuclear (MN) cells in patients with and without SS were noted. Ductal epithelial cells of SS biopsies expressed significantly increased levels of macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, interleukin-8 (IL-8) and RANTES (Regulated upon Activation, Normal T cell Expressed and Secreted). Biopsies from patients with SS showed that MIP-1beta was expressed by 51% of infiltrating cells, while 41% expressed MIP-1alpha, whereas 22 and 7% expressed RANTES and IL-8, respectively. CONCLUSION: Chemokines expressed by ductal epithelial cells may attract circulating leucocytes, in particular CD4+ T cells, towards the site of inflammation, thereby orchestrating the influx of MN cells characteristically seen in MSGs in SS. Chemokines may be induced directly by a putative triggering agent for SS, or secondary to the release of pro-inflammatory cytokines produced by epithelial cells. These findings further implicate epithelial cells as playing a major role in the pathogenesis of SS and implicate chemokines in the leucocyte recruitment in this setting.   相似文献   
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Saxton  HM; Borzyskowski  M; Mundy  AR; Vivian  GC 《Radiology》1988,168(1):147-150
Spinning top urethra (STU) is a term used to describe a widened posterior urethra seen mainly in girls. It is commonly regarded as a normal variant. The authors studied 30 girls with STU using videourodynamics. Twenty-eight showed bladder instability; 21, a congenital wide bladder neck anomaly; and 20, both instability and a wide bladder neck. One patient had a sensitive bladder. All patients had a urodynamic abnormality. The authors believe that the STU is nearly always an indication of bladder instability or wide bladder neck anomaly. The most common mechanism for the dilatation of the posterior urethra is that unstable contractions are resisted by a voluntary increase in distal sphincter tension so as to prevent leakage of urine. The resulting pressure rise produces distention of the posterior urethra, which will be maximal in subjects with a weak bladder neck mechanism as in the congenital wide bladder neck anomaly. The authors believe that STU is seldom if ever a normal variant.  相似文献   
100.
Multivessel diffuse coronary arteriopathy is the hallmark of chronic diabetic patients. The ideal method of revascularising this group of patients is controversial. This review examines the various modalities available in the revascularisation of coronary artery disease in diabetic patients. Various trials have been conducted to compare the effectiveness of surgical and percutaneous methods of revascularisation. Most of the important trials like BARI, CABRI, EMORY and Duke's database are critically analysed and a meaningful practical strategy to manage this difficult subgroup of patients is outlined. The recommendations may change after a few years if the new coated stents prove their worth.  相似文献   
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