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191.
Background
Previous research has shown a loss of bone mineral density (BMD) during pregnancy. This loss has been correlated to the occurrence of back pain symptoms during pregnancy. The objective of this study was to evaluate whether persistence of back pain symptoms 2 years after pregnancy could be associated with BMD changes as measured by quantitative USG of the os calcis. 相似文献192.
Effects of low-level radiation and comparative risk 总被引:2,自引:0,他引:2
193.
Amparo EG; Hoddick WK; Hricak H; Sollitto R; Justich E; Filly RA; Higgins CB 《Radiology》1985,154(2):451-456
Magnetic resonance imaging (MRI) was used to evaluate abdominal aortic aneurysms in 27 patients. The findings were compared retrospectively with CT, ultrasound (US), and angiography in 17 cases and prospectively with US in 10 cases. MRI identified the renal arteries in all cases, demonstrated involvement at or above the origin of the renal arteries in eight patients, and showed extension of the aneurysm into the iliac arteries in 12 cases. The outer dimension of the aneurysm, the diameter of the residual lumen, and the length of the aneurysm were measured easily from the MR images. The measurements of transverse dimension of the abdominal aortic aneurysm were similar for MRI, CT, and US. MRI more accurately defined extension above the renal arteries and below the aortic bifurcation. It is concluded that MRI provides the necessary information for the surveillance and preoperative evaluation of abdominal aortic aneurysms. 相似文献
194.
195.
KY Lau WWC Wong JKW Chan WK Kan JLY Leung ASL Lee LT Lee GYK Lee 《Journal of Medical Imaging and Radiation Oncology》2007,51(2):190-195
Emergency transcatheter embolization is a well‐recognized measure to manage patients with life‐threatening haemoperitoneum due to spontaneous ruptured hepatocellular carcinoma. Traditional embolization technique is to embolize the proper hepatic artery or the segmental hepatic artery by femoral approach using gelfoam pledgets. From 1997 to 2004, in 19 out of 96 embolizations, the embolization technique had to be modified because of tortuous conventional or aberrant hepatic vascular anatomy or parasitic supply to achieve successful embolization. 相似文献
196.
A rare-event analysis model for quantifying white cells in white cell- depleted blood 总被引:1,自引:1,他引:0
An analysis model to detect and quantify white cells (WBCs) in red cell concentrates (RBCC) drawn from units of blood that are highly depleted of WBCs is described. WBC detection is performed by fluorescence analysis of 50 microL of RBCC labeled with propidium iodide, a DNA/RNA fluorophore. Quantification is performed by regression analysis of standard dilutions of RBCC in substantially WBC-free red cells. This RBCC diluent is obtained by filtration of blood through a new medium. The method proves to be precise (CV = 7%), efficient (+/- 30 min/aliquot), and linear (r = 0.99) to 6 log10 WBC depletion of the native product. The current technique is preferable to those suggested previously, such as ficoll concentration, which requires the sacrifice of the unit of blood for counting purposes, and to earlier fluorescence analysis techniques that do not employ WBC-free red cell diluents. The latter do not monitor extremely low concentrations of WBCs because they lack adequate signal-to-noise discrimination. The sensitivity of the described method allows for monitoring of WBC depletion procedures with greater efficiency than is currently available commercially. 相似文献
197.
The combination of videofluorography and pulsed fluoroscopy using an analog videodisc system has previously been investigated with regard to image quality and potential for dose reduction. The authors found that the system could be improved still further by replacing the analog disc with a 512 X 512-pixel digital image system, thereby increasing fluoroscopic image quality and permitting stored images to be recorded with a multiformat camera. The pulsed method is compared with low-dose-rate fluoroscopy, in which a continuous image is obtained at 1/4 of the normal rate. Whereas image quality using a low dose rate was inadequate for any useful purpose, pulsed fluoroscopy was sufficient for all but the most critical stages of the examination. 相似文献
198.
Hricak H; Dooms GC; Jeffrey RB; Avallone A; Jacobs D; Benton WK; Narayan P; Tanagho EA 《Radiology》1987,162(2):331-336
The sensitivity, specificity, accuracy, and positive and negative predictive values of clinical assessment, computed tomography (CT), and magnetic resonance (MR) imaging were compared in the differentiation of stage B from stage C prostatic carcinoma. Forty-six patients who had undergone radical prostatectomy were included in the study. Surgical-pathologic staging was considered the "truth measure." Clinical staging had an accuracy of 61%, and CT, 65%. Accuracy for MR imaging depended on the instrument parameters and plane of section used. When only transverse T1-weighted images were analyzed, MR accuracy was 61%. However, when transverse T1- and T2-weighted images supplemented by additional T2-weighted coronal or sagittal images were studied, accuracy increased to 83%. At present, MR imaging is the most accurate diagnostic modality for the local staging of carcinoma of the prostate, but for optimal results, multiple sequences and two orthogonal planes of imaging are needed. 相似文献
199.
目的:建立一种高灵敏度、高特异性、精确、简便的微孔板酶联夹心杂交技术,定量检测人IL-18mRNN。方法:针对人IL-18mRNA RT-PCR产物—条链的不同区域序列设计—对特异探针,其中一条为捕获探针,5’端为氨基修饰,可以与微量DNA结合板表面的NOS基团共价结合,“竖直”地包被在微孔板内;另一条为检测探针,3’端标记生物素。提取人外周血单个核细胞中总RNA,进行RT-PCR扩增IL-18 mRNA,产物热变性后加入已包被捕获探针的微孔板内进行杂交,再加入检测探针与已杂交的产物结合,最后经亲和素-辣根过氧化物酶(SAV-HRP)系统检测杂交信号。结果:该法检测IL-18mRNA RT-PCR产物的灵敏度明显高于琼脂糖凝胶电泳,重复性良好,且结果数据化。结论:该方法具有操作简单、灵敏度高、特异性强等优点,适合于PCR扩增产物的定量检测。 相似文献
200.
Association between uncoupling protein polymorphisms (UCP2-UCP3) and energy metabolism/obesity in Pima indians 总被引:24,自引:0,他引:24
Walder K; Norman RA; Hanson RL; Schrauwen P; Neverova M; Jenkinson CP; Easlick J; Warden CH; Pecqueur C; Raimbault S; Ricquier D; Silver MHK; Shuldiner AR; Solanes G; Lowell BB; Chung WK; Leibel RL; Pratley R; Ravussin E 《Human molecular genetics》1998,7(9):1431-1435
The UCP2-UCP3 gene cluster maps to chromosome 11q13 in humans, and
polymorphisms in these genes may contribute to obesity through effects on
energy metabolism. DNA sequencing of UCP2 and UCP3 revealed three
polymorphisms informative for association studies: an Ala-->Val
substitution in exon 4 of UCP2, a 45 bp insertion/deletion in the 3'-
untranslated region of exon 8 of UCP2 and a C-->T silent polymorphism in
exon 3 of UCP3. Initially, 82 young (mean age = 30 +/- 7 years), unrelated,
full-blooded, non-diabetic Pima Indians were typed for these polymorphisms
by direct sequencing. The three sites were in linkage disequilibrium ( P
< 0.00001). The UCP2 variants were associated with metabolic rate during
sleep (exon 4, P = 0.007; exon 8, P = 0.016) and over 24 h (exon 8, P =
0.038). Heterozygotes for UCP2 variants had higher metabolic rates than
homozygotes. The UCP3 variant was not significantly associated with
metabolic rate or obesity. In a further 790 full-blooded Pima Indians,
there was no significant association between the insertion/deletion
polymorphism and body mass index (BMI). However, when only individuals
>45 years of age were considered, heterozygotes (subjects with the
highest sleeping metabolic rate) had the lowest BMI (P = 0.04). The
location of the insertion/deletion polymorphism suggested a role in mRNA
stability; however, it appeared to have no effect on skeletal muscle UCP2
mRNA levels in a subset of 23 randomly chosen Pima Indians. In conclusion,
these results suggest a contribution from UCP2 (or UCP3) to variation in
metabolic rate in young Pima Indians which may contribute to overall body
fat content later in life.
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