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排序方式: 共有2379条查询结果,搜索用时 15 毫秒
941.
JC Watson SC Hadler CA Dykewicz S Reef L Phillips 《Canadian Metallurgical Quarterly》1998,47(RR-8):1-57
These revised recommendations of the Advisory Committee on Immunization Practices (ACIP) on measles, mumps, and rubella prevention supersede recommendations published in 1989 and 1990. This statement summarizes the goals and current strategies for measles, rubella, and congenital rubella syndrome (CRS) elimination and for mumps reduction in the United States. Changes from previous recommendations include: Emphasis on the use of combined MMR vaccine for most indications; A change in the recommended age for routine vaccination to 12-15 months for the first dose of MMR, and to 4-6 years for the second dose of MMR; A recommendation that all states take immediate steps to implement a two dose MMR requirement for school entry and any additional measures needed to ensure that all school-aged children are vaccinated with two doses of MMR by 2001; A clarification of the role of serologic screening to determine immunity; A change in the criteria for determining acceptable evidence of rubella immunity; A recommendation that all persons who work in health-care facilities have acceptable evidence of measles and rubella immunity; Changes in the recommended interval between administration of immune globulin and measles vaccination; and Updated information on adverse events and contraindications, particularly for persons with severe HIV infection, persons with a history of egg allergy or gelatin allergy, persons with a history of thrombocytopenia, and persons receiving steroid therapy. 相似文献
942.
OBJECTIVE: Metallic coils have been used for vascular embolization for many years but controlled-release coils have only recently become commercially available. Most of these devices are microcoils that were manufactured primarily for the packing of intracerebral aneurysms; therefore, they lack radial force and are not ideal agents for the occlusion of high-flow lesions such as pulmonary arteriovenous malformations (PAVMs). The objective of this study was to review our experience with a new detachable coil based on the conventional Gianturco-Wallace coil. SUBJECTS AND METHODS: The new detachable coil was initially used for the treatment of varicocele in 20 patients. Subsequently, the coil was used in 48 patients during 90 procedures for the treatment of PAVMs. RESULTS: A total of 548 coils were used. Complete occlusion of the testicular vein was achieved in all patients with varicocele. Successful occlusion of the PAVM being treated was achieved in all patients, and no instances of recanalization were documented in any of the patients who returned for follow-up angiography. Forty-one coils had to be removed completely from the catheter before detachment because of inappropriate size or position. Eight coils failed to detach easily, and six of these had to be removed. Most of these device failures were associated with kinking of the screw thread mechanism between the coil and the delivery wire. CONCLUSION: The Jackson detachable coil allows safer, more accurate, and more distal embolization of PAVMs than is possible with nondetachable coils. Complications associated with its use have been few. 相似文献
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946.
NF Galeano M Al-Haideri F Keyserman SC Rumsey RJ Deckelbaum 《Canadian Metallurgical Quarterly》1998,39(6):1263-1273
Small dense low density lipoprotein (LDL) particles have altered apolipoprotein (apo) B conformation and lowered affinity for the LDL receptor (J. Biol. Chem. 1994. 269: 511-519). Herein, we examine the interaction of small dense LDL with cell LDL receptor-independent binding sites. Compared to normal LDL, at low LDL cell media concentrations (<10 microg/ml), small dense LDL had decreased specific binding to the LDL receptor on normal fibroblasts at 4 degrees C, but a 2-fold increased binding to LDL receptor-independent cell sites. At higher LDL concentration (100 microg/ ml), LDL receptor-independent binding of small dense LDL was 4.5-fold that of normal LDL in normal fibroblasts, but greater (2- to 14- fold) in LDL receptor-negative fibroblasts. In LDL receptor-negative fibroblasts at 37 degrees C, small dense LDL had higher (3-fold) cell association than normal size LDL but no effective LDL degradation. At high LDL concentrations (> or =100 microg/ml), LDL binding to normal or LDL receptor-negative fibroblasts was not affected by several anti-apoB monoclonal antibodies or by cell pretreatment with proteases, chondroitinase, or neuraminidase. In contrast, pretreating normal and receptor-negative fibroblasts with heparinase and heparitinase decreased LDL cell binding by 35% and 50%, respectively. Similarly, preincubation of receptor-negative fibroblasts with sodium chlorate, an inhibitor of proteoglycan sulfation, decreased LDL binding by about 45%. We hypothesize that small dense LDL might be more atherogenic than normal size LDL due to decreased hepatic clearance by the LDL receptor, and enhanced anchoring to LDL receptor-independent binding sites in extrahepatic tissues (e.g., the arterial wall), a process mediated, in part, by cell surface proteoglycans. 相似文献
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Cardiac fibrosis is linked to aldosterone-induced hypertension, but the effects on in vivo left ventricular (LV) function are not established. We studied the relations between in vivo LV function and aldosterone/salt cardiac fibrosis. Adult guinea pigs (GPs) were treated for 3 months with an aldosterone infusion and high-salt diet. This treatment induced arterial hypertension (+35%) and moderate LV hypertrophy (LVH; +60%) without right ventricular (RV) hypertrophy. Echo-Doppler LV assessment demonstrated unaltered cardiac output, stroke volume, or LV relaxation. Type I collagen messenger RNA (mRNA) was significantly increased in both ventricles (LV, +48%; RV, +77%) and accompanied by a significant increase in total collagen deposition (LV, from 0.52% in controls to 4.4% in treated GPs; RV, from 0.82 to 5.5% in treated GPs). Plasma norepinephrine levels increased 2.6-fold (p < 0.01) and correlated with the increase in collagen deposition in both ventricles. Collagen content was not correlated with hypertension or LVH. We conclude that aldosterone administration induces cardiac collagen accumulation and a sympathetic stimulation, which might preserve systolic and diastolic function. 相似文献
949.
Near-resonance saturation pulse imaging of the extraocular muscles in thyroid-related ophthalmopathy
JL Ulmer SC Logani LP Mark CA Hamilton RW Prost JN Garman 《Canadian Metallurgical Quarterly》1998,19(5):943-950
PURPOSE: We examined the utility of near-resonance saturation pulse imaging (magnetization transfer [MT] and spin lock) in characterizing microstructural changes occurring in the extraocular muscles of patients with thyroid-related ophthalmopathy (TRO). METHODS: Eight healthy volunteers and 10 patients with TRO were imaged using an off-resonance saturation pulse in conjunction with conventional spin-echo T1-weighted imaging at frequency offsets of 500, 1000, 1500, and 2000 Hz from water resonance. The relative contributions of MT and spin-lock excitation to image contrast at each frequency offset were estimated using a computer simulation model. Suppression ratios were calculated for the control and TRO groups from measurements obtained on two successive coronal sections in the widest portion of the inferior and medial rectus muscles bilaterally. A repeated measures analysis of variance and a parametric correlation analysis were performed to evaluate maximum cross-sectional area, MR-generated signal, and suppression ratios for the extraocular muscles examined. RESULTS: Our computer model suggested that saturation of extraocular muscles was due to pure MT effects with our off-resonance pulse at 2000 and 1500 Hz, to a combination of MT and spin lock at 1000 Hz frequency offset, and, primarily, to spin-lock excitation at 500 Hz frequency offset. Suppression ratios for the extraocular muscles of the TRO patients were significantly lower than that observed for the control subjects at 1500, 1000, and 500 Hz frequency offset. This differential saturation effect was maximal at 500 Hz frequency offset, with mean suppression ratios for the inferior and medial rectus muscles of 27% for the healthy subjects and 20% for the TRO group. CONCLUSION: Both MT and spin-lock contrast of the extraocular muscles in patients with TRO differ significantly from that observed in control subjects. Near-resonance saturation pulse imaging may enhance our understanding of the microstructural changes occurring in the extraocular muscles of these patients. 相似文献
950.