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151.
CA Dujovne J Eff L Ferraro RJ Goldstein AM Gotto WD Hall WS Harris SJ Held A Herd DB Hunninghake 《Canadian Metallurgical Quarterly》1993,72(15):1131-1136
Antihypertensive drugs may affect serum lipoprotein levels in mixed populations but data in hyperlipidemic patients are scanty. Atenolol versus celiprolol effects on serum lipoproteins were compared in 159 hyperlipoproteinemic hypertensive patients. This was a randomized, double-blind, parallel-group, positive-controlled multicenter trial with centralized lipoprotein laboratory and diet constancy monitoring. Blood pressure reduction and serum lipoprotein and apoprotein levels were monitored for 3 months. Both drugs reduced systolic and diastolic blood pressures. Atenolol had greater effects than celiprolol on diastolic pressure, but effects on systolic blood pressure were not different. Patients receiving atenolol had lower serum high-density lipoprotein cholesterol levels and higher low-density lipoprotein/high-density lipoprotein cholesterol ratios, whereas patients treated with celiprolol showed no contrasting changes. These differences in lipoprotein levels between drug treatment groups were statistically significant at weeks 9 and 12. The difference between drug treatments was also significant if the values of the 9- and 12-week visits were averaged. Patients taking atenolol had statistically significantly higher serum levels of total cholesterol, triglycerides and apoprotein B at 9 weeks. These divergent directional changes were consistent throughout and statistically significantly different between drugs. 相似文献
152.
LF Cardoso M Grinberg MA Ratti LP de Magalh?es I Antelmi CC Medeiros F Tarasoutchi EG Rossi WS Avila G Bellotti 《Canadian Metallurgical Quarterly》1993,61(2):87-91
PURPOSE: To compare immediate and long term results balloon mitral valvuloplasty (BMV) using double balloon or bifoil balloon. METHODS: One hundred and thirteen consecutive cases of BMV used aleatory double balloon (group DB--55 cases) or bifoil balloon (group BF--16 cases). Patients were similar regarding to age, sex, valvopaty etiology, functional class and echocardiographic score. Seventy one (63%) patients achieved 12 months follow-up. RESULTS: In group DB there were 2 (4%) insuccess, 2 (4%) cardiac tamponade and 2 (4%) deaths, 91% patients had immediate criteria of success. Mitral valve area (MVA) increased from 0.8 to 1.69cm2 and mitral gradient (G) by echodopplercardiographic (ECHO) decreased from 17.9 to 4.8mmHg. Three (5%) patients developed severe mitral regurgitation (MR) and needed surgical intervention. At follow-up 2 (4%) developed mitral restenosis. MVA estimated by ECHO study after one year follow-up was inferior to 1.15cm2 in 15 (32%) cases, between 1.5 and 2.0cm2 in 17 (37%) and superior to 2.0cm2 in 14 (31%). In group BF there were 2 (12.5%) insuccess, 4 (25%) developed severe MR occurring 1 death immediate post-operative mitral valve replacement. Among 14 (87%) success cases, MVA increased from 0.8 to 1.89cm2 and G decreased from 18 to 6.4mmHg. Lately 2 (12.5%) needed surgical intervention because significative MR. At 12th month follow-up the ECHO study showed that in one (10%) case MVA was < 1.5cm2, and in 3 (27%) cases was between 1.5 and 2.0cm2. CONCLUSION: There were similar good results in both groups, however group DB had more restenosis, cardiac tamponade and vascular complications and group BF had more severe MR. 相似文献
153.
S Parkkila AK Parkkila K Kaunisto A Waheed WS Sly H Rajaniemi 《Canadian Metallurgical Quarterly》1993,41(5):751-757
We studied the location of a membrane-bound carbonic anhydrase (CA IV) in the human male reproductive tract using a specific antiserum to human CA IV in conjunction with immunoblotting, immunoperoxidase, and immunofluorescence techniques. The microvilli and apical plasma membrane of the epithelial cells and the subepithelial smooth muscle layer of the epididymis, ductus deferens, and ampulla of the ductus deferens showed specific staining for CA IV. The epithelial cells of the prostate and seminal vesicle failed to stain for CA IV, however, whereas the subepithelial smooth muscle layer showed positive staining. No specific staining for CA II was seen in the epithelium of the epididymal duct or the proximal ductus deferens. The presence of CA IV in the epididymis was confirmed by immunoblotting, which revealed 35 KD and 33 KD polypeptides. The results show that the microvilli and the apical plasma membrane of the lining epithelium of the epididymal duct, ductus deferens, and ampulla of the ductus deferens contain the membrane-bound carbonic anhydrase isoenzyme IV. The presence of the enzyme in the epithelium of the epididymis and ductus deferens is probably linked to the acidification of the epididymal fluid that prevents premature sperm activation. Its physiological role in the smooth muscle cells remains to be elucidated. 相似文献
154.
155.
WS Fletcher SS Lum RW Nance RF Pommier MS O'Dorisio 《Canadian Metallurgical Quarterly》1997,70(5-6):561-563
On the basis that melanomas are of neural crest origin and might contain somatostatin receptors, the authors utilized 111In Pentetreotide (OctreoScan) to image 16 melanoma patients with known sites of disease. Twelve of 16 patients were positive with 38 percent imaging all sites. No lesion less than 1.5 cm imaged nor did one ocular and one amelanotic melanoma. Of the five described somatostatin receptors, OctreoScan binds only 2 and 5 suggesting that not all melanomas contain those receptors. It is concluded that melanomas contain somatostatin receptors and that this property might be used for imaging, tumor suppression with Octreotide, and/or as a target for Octreotide labelled with therapeutic agents such as immune complexes, chemotherapeutic agents or high energy radioisotopes. 相似文献
156.
WS McMahon R Mukherjee PC Gillette FA Crawford FG Spinale 《Canadian Metallurgical Quarterly》1996,31(2):314-323
OBJECTIVES: Comparison of the effects of supraventricular tachycardia-induced dilated cardiomyopathy on left and right ventricular isolated myocyte geometry and function. BACKGROUND: Chronic ventricular tachycardia and supraventricular tachycardia cause left ventricular dilation and dysfunction in humans. However, it is unknown whether supraventricular tachycardia-induced dilated cardiomyopathy is a homogenous process for both the left and right ventricles. METHODS: Dilated cardiomyopathy was induced by rapid atrial pacing (240 beats/min, 3 weeks) in 5 pigs. Five age- and weight-matched pigs served as controls. Ventricular mass was measured, myocyte dimensions were obtained, and isolated right and left ventricular myocyte contractile performance was evaluated at baseline and after beta-adrenergic receptor stimulation. RESULTS: With the development of dilated cardiomyopathy, there was no change in left ventricular mass. In contrast, right ventricular mass was increased, as was right ventricular myocyte cross-sectional area. In the control group, baseline right ventricular myocyte contractile function was increased compared to left ventricular myocytes. beta-adrenergic receptor stimulation increased myocyte contractile function in both left and right ventricular myocytes. With supraventricular tachycardia-induced cardiomyopathy, both left and right ventricular myocyte contractile function and beta-adrenergic responsiveness were reduced. CONCLUSIONS: This study demonstrated differences in left and right ventricular myocyte growth with supraventricular tachycardia-induced dilated cardiomyopathy and this differential growth response was associated with changes in contractile performance. Thus, in this model of cardiomyopathic disease, left and right ventricular growth and changes in contractile performance are not a homogenous process. 相似文献
157.
HM Abdel-Dayem SY Naddaf WS Omar M Aziz J Gillooley 《Canadian Metallurgical Quarterly》1997,38(8):1213-1215
We report an unusual finding in an AIDS patient who presented with a large mediastinal mass and multiple lymphadenopathy. A sequential thallium and gallium scan to specify the nature of the mediastinal mass was requested. The early thallium images, acquired 15 min after the intravenous injection, showed no uptake in the mass. The delayed images 2 hr later showed intense thallium uptake. A gallium scan performed 48 hr later also showed intense gallium uptake in the mediastinal mass. Biopsy from the inguinal lymph node confirmed the presence of large-cell diffuse noncleaved malignant lymphoma. This case raises questions about the optimum time of imaging for thallium in high-grade lymphoma, whether delayed imaging is essential, about previous reports of low sensitivity of thallium in undifferentiated lymphoma and about the mechanism of thallium uptake in this type of tumor. 相似文献
158.
M Pantaleon MB Harvey WS Pascoe DE James PL Kaye 《Canadian Metallurgical Quarterly》1997,94(8):3795-3800
The first differentiative event in mammalian development is segregation of the inner cell mass and trophectoderm (TE) lineages. The epithelial TE cells pump fluid into the spherical blastocyst to form the blastocyst cavity. This activity is fuelled by glucose supplied through facilitative glucose transporters. However, the reported kinetic characteristics of blastocyst glucose transport are inconsistent with those of the previously identified transporters and suggested the presence of a high-affinity glucose carrier. We identified and localized the primary transporter in TE cells. It is glucose transporter GLUT3, previously described in the mouse as neuron-specific. In the differentiating embryo, GLUT3 is targeted to the apical membranes of the polarized cells of the compacted morula and then to the apical membranes of TE cells where it has access to maternal glucose. In contrast, GLUT1 was restricted to basolateral membranes of the outer TE cells in both compacted morulae and blastocysts. Using antisense oligodeoxynucleotides to specifically block protein expression, we confirmed that GLUT3 and not GLUT1 is the functional transporter for maternal glucose on the apical TE. More importantly, however, GLUT3 expression is required for blastocyst formation and hence this primary differentiation in mammalian development. This requirement is independent of its function as a glucose transporter because blastocysts will form in the absence of glucose. Thus the vectorial expression of GLUT3 into the apical membrane domains of the outer cells of the morula, which in turn form the TE cells of the blastocyst, is required for blastocyst formation. 相似文献
159.
SL Johnson MA Gates M Johnson WS Talbot S Horne K Baik S Rude JR Wong JH Postlethwait 《Canadian Metallurgical Quarterly》1996,142(4):1277-1288
The ease of isolating mutations in zebrafish will contribute to an understanding of a variety of processes common to all vertebrates. To facilitate genetic analysis of such mutations, we have identified DNA polymorphisms closely linked to each of the 25 centromeres of zebrafish, placed centromeres on the linkage map, increased the number of mapped PCR-based markers to 652, and consolidated the number of linkage groups to the number of chromosomes. This work makes possible centromere-linkage analysis, a novel, rapid method to assign mutations to a specific linkage group using half-tetrads. 相似文献
160.
Clinical experience of arthroscopy in 12 temporomandibular joints with a clinical diagnosis of closed lock was described. There were 10 patients and all were females with a mean age of 31.2 years (range 20 to 59 years). The antero-lateral approach was used for entry into 11 joints. The clinical findings were adhesions (64%), fibrillation (64%), anterior displacement of disc (36%) and scuffing of the articular surface of the glenoid fossa (9%). Two of the joints that had arthrocentesis prior to arthroscopy did not show any different findings from the rest. Of the 8 patients who had pre-arthroscopy pain, 7 patients (88%) had reduction of the symptom. Three patients (38%) had complete resolution of pain. The range of mouth opening (measured as maximal incisor opening) increased in all patients two weeks following arthroscopy. The average change in maximal incisor opening was 40.3% with a range of 22% to 85%. The mean follow-up was 34 months (range 4 to 68 months). 相似文献