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121.
Venous angioma of the brain is a rare congenital vascular anomaly. In the last few years there have been several reports on the angiographic appearance of this lesion, but very little has been written about the findings on computed tomography (CT). Angiographically, the arterial phase is normal, while the capillary phase might demonstrate a blush. The major abnormality is the venous phase, where multiple dilated medullary veins converge centrally into a large drainage vein. The two cases presented here correlate the angiographic and CT appearances. It is felt that, with a knowledge of these findings, an accurate diagnosis of this condition can usually be reached. 相似文献
122.
Students at the University of Colorado School of Medicine were surveyed using an inventory of problems and conerns relating to their personal and academic lives. Results were to provide a data base for improvement of their educational environment via the ecosystem design process. The survey revealed that chief among student conerns are a lack of personal freedom, excessive academic pressures, and feelings of dehumanization. A marked trend toward increasing difficulty with thoughts of having chosen the wrong profession is noted over the four class levels. The authors offer several hypotheses relating to the underlying conditions responsible for these findings and discuss their possible relation to the current malpractice insurance crisis. 相似文献
123.
MT Chateau C Ginestier-Verne J Chiesa R Caravano JP Bureau 《Canadian Metallurgical Quarterly》1996,10(2):75-84
The effects of two oral contraceptives, containing gestodene and either 20 micrograms or 30 micrograms ethinylestradiol, on hemostatic parameters was investigated in a six-month randomized study involving a total of 40 healthy women between the ages of 18 and 30 years. A large number of hemostatic parameters were measured, which were categorized as either pro-coagulatory, anti-coagulatory, profibrinolytic, anti-fibrinolytic or indicative of fibrin turnover. Additionally, tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI-1) were measured before and after venous occlusion and delta and ratio values calculated. Pro-coagulatory factors as well as reaction products reflecting in vivo coagulatory activity (thrombin-antithrombin III complex, prothrombin fragment 1 + 2) were found to increase. Among the anti-coagulatory parameters, only protein S concentration and protein S activity decreased, most notably in the 30 micrograms EE group. There was a corresponding increase in fibrinolytic activity reflected by reaction products of in vivo fibrinolysis (plasmin-antiplasmin 2-complex, fibrin-degradation products). Measurement of t-PA and PAI-1, before and after venous occlusion, revealed that the fibrinolytic response was more pronounced in the 20 micrograms EE group. There was also an increase in the threshold of fibrinolytic inhibition (ratio PAI-1) in both groups, which was less pronounced in the 20 micrograms EE group. Apart from isolated measurements, all parameters remained within their normal ranges and values returned to baseline in the follow-up cycle. It is concluded that both preparations had a balanced effect on the hemostatic system stimulating both pro-coagulant and fibrinolytic activity. No statistically significant differences were observed between the two groups; however, there was a trend towards greater fibrinolytic capacity in the 20 micrograms EE group. 相似文献
124.
The synthesis of rac-2,5,6-tri-O-butyryl-myo-inositol 1,3,4-trisphosphate hexakis(acetoxymethyl) ester [Bt3-Ins(1,3,4)P3/AM, 1], a membrane-permeant derivative of myo-inositol 1,3,4-trisphosphate [Ins(1,3,4)P3] is reported. 1 inhibited calcium-mediated chloride secretion of T84 cells, suggesting a regulatory link of Ins(1,3,4)P3 and the biosynthesis of the known inhibitor myo-inositol 3,4,5,6-tetrakisphosphate. 相似文献
125.
Thermal analysis as a screening technique in preformulation studies of picotamide solid dosage forms
P Mura MT Faucci A Manderioli S Furlanetto S Pinzauti 《Canadian Metallurgical Quarterly》1998,24(8):747-756
The potential compatibilities of several commonly used pharmaceutical excipients with picotamide were evaluated using differential scanning calorimetry (DSC). The effects of aging and of mechanical treatment (blending, grinding, or kneading) of samples were also evaluated. Hot-stage microscopy (HSM) and scanning electron microscopy (SEM) were used as complementary techniques to implement and assist in interpretation of the DSC results. DSC analysis evidenced a noticeable modification of drug thermal features in the mixtures with palmitic acid, stearic acid, stearyl alcohol, polyethylene glycol (PEG) 20,000, and sorbitol, but HSM analysis showed that the DSC behavior was mainly because of the drug dissolution in the melted excipient, which allowed the presence of important solid-solid interactions to be excluded. Compatibility with Mg stearate was also found, even if sample manipulation induced the partial conversion of Mg stearate in a pseudo-polymorphic modification. Mechanical stress displayed an increased hygroscopicity of mixtures with glucose and lactose, as well as some solid-solid interactions with lactose and mannitol. 相似文献
126.
MT Dorak G Owen I Galbraith N Henderson D Webb KI Mills C Darke AK Burnett 《Canadian Metallurgical Quarterly》1995,9(5):875-878
A molecular analysis was carried out in 63 sequentially diagnosed childhood acute lymphoblastic leukemia (ALL) patients and 1011 controls to investigate the homozygosity rate for HLA-DR53. HLA-DR53 is associated with acute myeloblastic leukemia at the protein level, and our previous study has shown its association with early-onset chronic myeloid leukemia only in homozygous form at the DNA level. In the present study, the homozygosity rates for DR53 were 17.5 and 13.6% in patients and controls, respectively. Ten of the 11 homozygous patients were boys. In the common ALL group (n = 40), all seven DR53 homozygous patients were boys, and among 19 girls this genotype was not observed (P = 0.006). For males, homozygosity for DR53 revealed a relative risk (RR) of 3.29 (P = 0.008) for common ALL. Five of the 11 relapsed patients were homozygous for DR53. Heterozygous frequencies for HLA-DR53 were not different between patients and controls. Homozygosity for DR53 was associated with a very high relapse rate (45.5 vs 7.7%, P = 0.002, RR = 9.1). These results extended our findings in chronic myeloid leukemia and showed the recessive nature and the male predominance of the interactive HLA influence on the development of childhood leukemia. Molecular mimicry of an HLA-DR53 epitope by oncogenic (retro)viruses or putative susceptibility genes in linkage disequilibrium with HLA-DR53 may be responsible for this association. 相似文献
127.
Glomerular diseases are associated with changes in glomerular membrane permeability properties that alter filtration rate of plasma water and barrier function of the capillary wall. To estimate intrinsic permeability properties that regulate transmembrane transport of water and macromolecules, theoretical analysis of renal clearance of tracer molecules can be used. The development of adequate theoretical models is required to achieve sufficient accuracy to simulate complicated biological processes. Current research in this area is aimed at improving and validating the presently available models in order to characterize the nature of permeability changes associated with pathological conditions. This is a key step in understanding the pathophysiological nature of glomerular diseases and in the development of effective treatments. 相似文献
128.
129.
M Palestini G Colarieti G Alessi S Urso L Vecchi M Aleandri MT Teofili M Borghese 《Canadian Metallurgical Quarterly》1993,143(5):375-382
The efficacy and tolerability of pyritinol (PY) and auranofin (AU) were compared in a multicentre double-blind study. Patients with RA received 600 mg/day PY or 6 mg/day AU for 1 year. Response was rated by a defined improvement in at least four of the following: Ritchie index, joint swelling index, rating scales for pain and general well-being, functional index, morning stiffness, ESR. Of the 139 fully evaluable PY patients 61 (44%) dropped out due to adverse events or response failure compared with 44 (31%) of the 142 AU patients. In patients treated for 1 year efficacy parameters improved more in the PY than in the AU group, with significant differences for the general well-being (P = 0.022), ESR (P = 0.029) and haemoglobin (P = 0.0042). The response rate for PY (61/78 patients, 78%) was significantly superior to AU (58/98 patients, 59% P = 0.009). An intention-to-treat analysis corroborated this result (P = 0.030). Adverse events (AE) occurred in 64% of PY patients and in 58% of AU patients: main AE were mucocutaneous symptoms (PY 36%, AU 23%) and gastrointestinal complaints (PY 30% AU 37%). Single cases of proteinuria, hepatic and haematological abnormalities were noted in both groups. 相似文献