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101.
Chen RY Westfall AO Raper JL Cloud GA Chatham AK Acosta EP Pham SV Tolson JM Heudebert GR Saag MS 《AIDS research and human retroviruses》2002,18(13):909-916
To determine the long-term immunologic and virologic effects of antiretroviral treatment interruptions, a retrospective analysis of an ongoing observational database was performed at a university HIV clinic. All patients who began highly active antiretroviral therapy (HAART) after January 1, 1996 and (1) were HAART experienced for >/=90 days, (2) had a treatment interruption (TI) for >/=30 days, (3) resumed HAART for >/=30 days, and (4) had CD4(+) cell counts performed pre- and post-TI were included. Main outcome measures included the following: Immunologic success was defined as a post-TI CD4(+) cell count >90% of the pre-TI CD4(+) cell count (post-TI/pre-TI, >90%). Virologic success was defined as a post-TI viral load (VL) less or equal to twice the pre-TI VL (post-TI/pre-TI, =2) or a post-TI VL of <1000 copies/ml. The pre-TI (baseline) value was the value at the start of the TI (range, -20 to +7 days); the post-TI value was the highest CD4(+) cell count and lowest VL copy achieved during the follow-up window (270 days). One thousand and eight patients were included in the analysis and 75 met the inclusion criteria. Forty-four of 75 patients (58.6%) achieved a successful immunologic outcome and 52 of 68 patients (76.5%; 7 patients did not have a VL determined within the specified periods) achieved a successful virologic outcome. No factors predicting success were identified. The median CD4(+) cell counts pre- and post-TI were 233 and 231 cells/microl, respectively; the median VLs pre- and post-TI were 11,456 and 404 copies/ml, respectively. We conclude that the majority of our patients in virologic failure who underwent a temporary TI recovered 90% of their baseline CD4(+) cell counts and returned to within 2-fold of their baseline VL when HAART was resumed. 相似文献
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Peter B. Barker Steven N. Breiter Brian J. Soher John C. Chatham John R. Forder Michael A. Samphilipo Carolyn A. Magee James H. Anderson 《Magnetic resonance in medicine》1994,32(2):157-163
Quantitative, single-voxel proton NMR spectroscopy of normal brain was performed in five adult beagle dogs using the cerebral water signal as an internal intensity reference. The same brain regions were then rapidly isolated and frozen using a pneumatic biopsy drill, perchloric acid extracted, and analyzed by biochemical assay and high-resolution NMR spectroscopy. The concentrations of the major resonances in the in vivo and in vitro spectra were compared, and good agreement was found between the different measurements. The in vivo spectra contained three peaks at 3.21, 3.04, and 2.02 ppm, which are usually assigned to trimethylamines (TMA), creatines, and N-acetyl derivatives (NAc), which corresponded to be the following metabolite concentration values: 1.7 ± 0.6, 7.7 ± 2.1, and 10.9 ± 2.7 μmol/g wet weight respectively. In vitro, the following metabolite concentrations were measured: glycerophosphocholine (GPC) 1.3 ± 0.2, phosphocholine (PC) 0.5 ± 0.1, phosphocreatine (PCr) 2.6 ± 0.4, creatine (Cr) 5.9 ± 1.4, and N-Acetyl aspartate (NAA) 8.9 ± 1.8 μmol/g wet weight. Therefore, the 3.21 ppm resonance observed in the in vivo spectrum is predominantly GPC and PC in a ratio of 2.6:1, the 3.04 ppm resonance is Cr and PCr in a ratio of 2.3:1, and the 2.02 ppm resonance is predominantly (≈?80%) NAA with small contributions from N-acetylaspartyl-glutamate (NAAG) and glutamate. The data presented here validate the technique of water referencing as a simple and convenient means of quantitating single-voxel in vivo proton NMR spectra of the brain. 相似文献
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Endolymphatic sac tumors: radiologic appearance 总被引:5,自引:0,他引:5
Lo WW; Applegate LJ; Carberry JN; Solti-Bohman LG; House JW; Brackmann DE; Waluch V; Li JC 《Radiology》1993,189(1):199
109.
目的 :为了检验一个新的学说 :是胰岛素而不是胰岛素样生长因子 (IGF-1 )激活肝脏副交感神经反射。方法 :应用快速胰岛素敏感试验 (RIST)方法。其指标是 :在胰岛素或胰岛素样生长因子 (IGF- )推注后为了维持大白鼠实验期间的正常血糖水平而灌注的葡萄糖量。我们比较了胰岛素 5 0 mu/kg及 IGF- 2 0 0μg/kg输入实验的大白鼠体内后的血糖贮存量。结果 :IGF- 2 0 0 μg/kg与胰岛素 5 0 mu/kg有相似的低血糖作用。通过输入阿托品 (1 .0 mg/kg)阻断肝脏副交感神经反射导致胰岛素抵抗 ,而对 IGF- 无影响。结论 :是胰岛素而不是IGF- 激活肝脏副交感神经反射释放出一种激素刺激血糖在骨骼肌的摄取 相似文献
110.
Acetabular fractures: optimal imaging 总被引:3,自引:0,他引:3
In 19 cases of acetabular fracture, computed tomography (CT) with volumetric three-dimensional (3D) reconstructions displayed as video loops about horizontal and vertical axes of rotation replaced the traditional imaging combination of CT and multiple plain radiographs, while offering significant advantages. Overlying bowel content or foreign matter obscured detail in 36 of 45 plain radiographic views, and positioning or radiographic technique was suboptimal in 21. Three-dimensional reconstructions completely eliminated these problems. These 3D reconstructions accurately simulated oblique, inlet, and tangential views in all cases. In ten of 19 cases a nonconventional oblique view, and in 13 of 19 cases a cephalocaudal angulation other than the inlet, tangential, or anteroposterior view, best demonstrated the fracture. Elimination of five plain radiographs resulted in a skin radiation dose savings of 5 rad (50 mGy). No difficult or painful patient positioning was required beyond that necessary for the standard CT examination. 相似文献