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J R?sch CT Dotter AJ Seaman JM Porter HH Common 《Canadian Metallurgical Quarterly》1976,127(4):553-558
Sequential ascending venographic studies were used to assess the healing of deep venous thrombosis in 50 patients randomly assigned to streptokinase or heparin therapy. Various degrees of thrombolysis and/or recanalization were demonstrated by venograms performed on the fourth and tenth days of treatment. Late follow-up studies (mean, 7 months after treatment) showed three basic patterns of resolution: (1) return to normal, (2) complete recanalization, and (3) incomplete recanalization and/or collateralization. Loss of valves or their function was associated with recanalization. The character, speed, and outcome of healing reflected the nature and extent of thrombosis, prior thrombotic disease in the extremity, and the type and timing of treatment. Streptokinase was highly effective and preferable to heparin in patients with deep vein thrombosis when therapy was begun within 4 days of onset of symptoms. In later stages of acute or recurrent deep vein thrombosis, the effectiveness of both drugs was significantly reduced. 相似文献
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KC Ueng SA Chen CE Chiang CT Tai SH Lee CW Chiou ZC Wen CJ Tseng YJ Chen WC Yu CY Chen MS Chang 《Canadian Metallurgical Quarterly》1996,7(11):1017-1023
INTRODUCTION: The dimension of Koch's triangle in patients with AV nodal reentrant tachycardia has not been well described. Understanding the dimension and anatomical distance related to Koch's triangle might be useful in avoiding accidental AV block during ablation of the slow pathway. The purposes of this study were to define the dimension of Koch's triangle and its related anatomical distance and correlate these parameters with the successful ablation sites in patients with AV nodal reentrant tachycardia. METHODS AND RESULTS: We studied 218 patients with AV nodal reentrant tachycardia. The distance between the presumed proximal His-bundle area and the base of the coronary sinus orifice (DHis-OS) measured in the right anterior oblique view was used to define the dimension of Koch's triangle. The distance of the proximal His-bundle recording site from the successful ablation site (DHis-Ab) and the distance as a fraction of the entire length of Koch's triangle (DHis-Ab/DHis-Os) were determined. The mean DHis-Os and DHis-Ab were 25.9 +/- 7.9 and 13.4 +/- 3.8 mm, respectively. DHis-Os negatively correlated with patient age (r = -0.41, P < 0.0001) and body mass index (r = -0.18, P = 0.004). Among the patients with successful ablation sites in the medial area, DHis-Os was longer (27.2 +/- 6.6 vs 24.6 +/- 8.4 mm, P < 0.005), DHis-Ab was similar (12.9 +/- 3.1 vs 13.9 +/- 4.0, P > 0.05) and DHis-Ab/DHis-Os was smaller (0.48 +/- 0.04 vs 0.74 +/- 0.11, P < 0.05). Furthermore, the patients with successful ablation sites in the medial location needed more radiofrequency pulse numbers than those in the posterior location (6 +/- 4 vs 4 +/- 3, P < 0.05). CONCLUSION: The site of successful slow pathway ablation was consistently about 13 mm from the site recording the proximal His-bundle deflection in patients with AV nodal reentrant tachycardia despite marked variability in the dimensions of Koch's triangle; therefore, patients with large triangles required ablation in the medial region rather than the posterior region. Care should be taken when delivering radiofrequency energy to the posteroseptal area in patients with shorter DHis-Os to avoid injury to AV node. 相似文献
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The yellow-pigmented bacterium isolated from a ditch was a gram negative rod with a G+C content of 63 mol%, and was classified in the genus Sphingomonas. Electron microscopy revealed that the bacterial cell surface was covered with many large plaits. When grown in a medium containing a polysaccharide as an essential nutrient, a pit of 0.02-0.1 micrometers in diameter was formed on the cell surface, and a thin section showed the rearrangement of the plaits and the presence of a region where the cell membrane sinks into the cytosol. The dependence of the pit formation on the presence of macromolecule may predict the existence of a direct uptake mechanism for macromolecules through a mouth-like pit, possibly in endocytosis fashion. The confirmation of the pit structure is the first such finding in the history of microbiology and may provide a new insight into the cell morphology and biochemistry of macromolecule transport in microbial cell system. 相似文献
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CT Tyrrell PF Bruning F May-Levin C Rose L Mauriac M Soukop JM Ford 《Canadian Metallurgical Quarterly》1995,(12):1976-1980
Pamidronate is a potent biphosphonate which modulates tumour-induced osteolysis (TIO) by inhibiting osteoclast-mediated bone resorption. In a phase II trial, 69 breast cancer patients with symptomatic progressive bone metastases were given infusions of pamidronate 60 mg over 1 or 4 h every 2 weeks for a maximum of 13 infusions or until progressive disease (PD) at any site. No other systemic anticancer therapy was allowed. Pain was measured using a visual analogue scale, mobility using a detailed eight-point questionnaire and analgesic intake using a six-point scale. Improvements in pain, mobility and analgesic scores occurred in 61, 50 and 30% of patients, respectively, with 33, 21 and 16% achieving a 40% improvement for > or = 8 weeks. At trial discontinuation, baseline levels of pain and mobility had improved by 27% (P = 0.001) and 20% (P = 0.004), respectively, despite a one category reduction in analgesic intake in 27% of patients. Using this relatively high dose of pamidronate, symptomatic response was independent of the number of bone metastases and also of infusion rate. The infusions were well tolerated with no major toxicities reported. Pamidronate infusions provide useful palliation for breast cancer patients with symptomatic bone metastases. 相似文献
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CT Hartrick 《Canadian Metallurgical Quarterly》1997,84(6):1392-1393
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HD Craig M Günel O Cepeda EW Johnson L Ptacek GK Steinberg CS Ogilvy MJ Berg SC Crawford RM Scott E Steichen-Gersdorf R Sabroe CT Kennedy G Mettler MJ Beis A Fryer IA Awad RP Lifton 《Canadian Metallurgical Quarterly》1998,7(12):1851-1858
Cerebral cavernous malformation (CCM) is a Mendelian model of stroke, characterized by focal abnormalities in small intracranial blood vessels leading to hemorrhage and consequent strokes and/or seizures. A significant fraction of cases is inherited as an autosomal dominant trait with incomplete penetrance. Among Hispanic Americans, virtually all CCM is attributable to a founder mutation localized to 7q ( CCM1 ). Recent analysis of non-Hispanic Caucasian kindreds, however, has excluded linkage to 7q in some, indicating at least one additional CCM locus. We now report analysis of linkage in 20 non-Hispanic Caucasian kindreds with familial CCM. In addition to linkage to CCM1, analysis of linkage demonstrates linkage to two new loci, CCM2 at 7p13-15 and CCM3 at 3q25.2-27. Multilocus analysis yields a maximum lod score of 14.11, with 40% of kindreds linked to CCM1, 20% linked to CCM2 and 40% linked to CCM3, with highly significant evidence for linkage to three loci (linkage to three loci supported with an odds ratio of 2.6 x 10(5):1 over linkage to two loci and 1.6 x 10(9):1 over linkage to one locus). Multipoint analysis among families with high posterior probabilities of linkage to each locus refines the locations of CCM2 and CCM3 to approximately 22 cM intervals. Linkage to these three loci can account for inheritance of CCM in all kindreds studied. Significant locus-specific differences in penetrance are identified. These findings have implications for genetic testing of this disorder and represent an important step toward identification of the molecular basis of this disease. 相似文献