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排序方式: 共有470条查询结果,搜索用时 15 毫秒
31.
32.
The impact of computed tomography on neuroradiologic practice 总被引:1,自引:0,他引:1
33.
MS Sekhon HL KhatriDepatment of Surgery Rohtak Medical College Rohtal India 《中华医学杂志(英文版)》1982,95(12):912-914
Spurred by recent advances in the ancient
science of acupuncture in China, world interest
in the subject has renewed. While the benefits
of acupuncture are evident, its. mode of action
and the existence of channels and collaterals are
major controversial subjects. Based on personal
experience and that of some of their colleagues
and patients, the authors believe that channels
and collaterals exist. These channels not only
play a role in the treatment of deep seated dis-
eases and analgesia induction and probably a.lso
moderate normal healthy perception. The ex-
istence of channels and their collaterals has not
been proved anatomically. 相似文献
34.
35.
Background
The Malaysian Ministry of Health promotes breast self-examination (BSE) for all women, and Pap smear screening every three years for all sexually active women ages 20 years and above. The objectives of this paper were to examine the practice of these two screening tests among women production workers in electronics factories, and to identify factors related to practice. 相似文献36.
Magill HL; Clarke EA; Fitch SJ; Boulden TF; Ramirez R; Siegle RL; Somes GW 《Radiology》1986,161(3):625-630
A multicenter clinical study was conducted using iohexol, a second-generation nonionic contrast medium, for excretory urography performed in 130 children. Doses of iohexol (300 mg iodine/ml) ranged between 150 and 660 mgI/kg (0.5 and 2.2 ml/kg). Iohexol was tolerated well, and no significant adverse reactions occurred. Sixty-five iohexol urograms were evaluated to determine the minimum dose for adequate visualization of the kidneys and collecting systems. A dose greater than 300 mgI/kg (1.0 ml/kg) always resulted in a urogram of diagnostic quality, while visualization was insufficient for diagnosis in 10% of studies done with doses of 150-300 mgI/kg (0.5-1.0 ml/kg). Another 65 iohexol urograms were compared in a blinded manner with a similar number of studies performed using iothalamate meglumine at comparable iodine concentration and dose. Visualization of calyces and pelvoinfundibular structures achieved with iohexol was rated better with statistical significance, but there was no difference in visualization of the renal parenchyma or ureters. Use of iohexol in excretory urography may be advantageous in children who are at greatest risk for an adverse reaction to contrast media or in those most likely to benefit from use of a low osmolality contrast agent. 相似文献
37.
Breast and axillary tissue MR imaging: correlation of signal intensities and relaxation times with pathologic findings 总被引:1,自引:0,他引:1
We tested a variety of inversion-recovery (IR) and spin-echo (SE) sequences by imaging the breast masses of 22 patients before surgery and 23 tissue specimens with magnetic resonance (MR) imaging at 0.6 T to determine the most effective pulse sequences to evaluate breast disease. An SE pulse sequence using a long repetition time (TR) of 1,600 msec and a long echo time (TE) of 90 msec was found to be the most sensitive in depicting carcinoma in the excised tissue specimens, with all of the carcinomas (n = 15) demonstrating irregular areas of higher signal intensity (SI) than that of the adjacent fat. However, only five of 11 breast carcinomas present in the preoperative patients produced a higher SI than that produced by fat on the same T2-weighted sequence. Five of the remaining six carcinomas in the preoperative patients appeared as localized distortions of fibroductular architecture on both T2-weighted SE and IR sequences. In axillary tissue specimens, both metastatic carcinoma and hyperplastic lymph nodes produced a high SI on T2-weighted SE sequences. However, metastatic carcinoma had a significantly longer T2 relaxation time than did hyperplastic lymph nodes. 相似文献
38.
H. PESSAH-RASMUSSEN P. JERNTORP L. STAVENOW S. ELMSTHL F. HANSEN J. SEIDEGRD H. GALVARD L. BRATTSTR
M A. HAMFELT 《Journal of internal medicine》1990,228(1):17-22
Abstract. A total of 1280 80-year-old men in the community of Malmö were questioned about smoking habits and the occurrence of cardiovascular disease (CVD). After a careful medical and duplex ultrasound examination, four groups were selected for further studies: (1) no CVD, non-smokers; (2) no CVD, smokers; (3) CVD, smokers; (4) CVD, non-smokers. In total 122 individuals participated. The average tobacco consumption by smokers was 13 g d?1 for 59 years. In the CVD group 45% of subjects had atherosclerotic symptoms at more than one site. Smoking was found to be correlated with lower extremity atherosclerosis, cholesterol and LDL cholesterol were correlated with carotid artery lesions and pathological ankle/arm index, and blood pressure was correlated with lower extremity lesions. In contrast with middle-aged populations, individuals with an increasing degree of lesions in the lower extremities had a larger percentage of high glutathione transferase activity than subjects without CVD. Smokers had significantly lower pyridoxal-5-phosphate levels than non-smokers. It is concluded that some heavy smokers might reach an advanced age in good health. Smoking was also operative as a risk indicator for lower extremity atherosclerosis in 80-year-old individuals. 相似文献
39.
目的:为保护濒死心肌提供机会窗口,对比观察经冠脉移植自体骨髓单个核细胞或间充质干细胞后,实验性急性心肌梗死动物心功能变化及心肌组织核转录因子кB、心肌细胞凋亡情况。方法:实验于2005-03/2006-11在河北省人民医院实验中心完成。选用24只雄性冀中白猪,随机数字表法分为4组:正常对照组、模型组、单个核细胞组、间充质干细胞组,6只/组。①24只猪均以盐酸氯胺酮200mg臀部肌肉注射麻醉后,分别于各自右侧股骨抽取骨髓20mL,采用Fercoll法分离获得骨髓单个核细胞,加入胶体金溶液,培养12~16h待用。分离过程中取出含有骨髓单个核细胞成分的细胞层,常规培养传代,每3d换液1次,贴壁生长细胞即为骨髓间充质干细胞,加入胶体金溶液,培养24h待用。②除正常对照组外,其余各组均经导管球囊封闭第一对角支以远的前降支,复制猪急性心肌梗死模型。单个核细胞组、间充质干细胞组均于造模后立即开通前降支,分别经球囊注入预先分离的骨髓单个核细胞6×108个、间充质干细胞6×108个。模型组造模后于梗死1h开通前降支,经球囊注入磷酸盐缓冲液10mL。③各组分别于术前及术后4周经心脏超声检测心功能,取材行病理学检查、心肌组织核转录因子кB的免疫组织化学检测及心肌细胞凋亡检测。结果:24只雄性白猪均进入结果分析。①心功能变化:术前各组左心室收缩末内径、左心室舒张末内径、左心室射血分数、短轴缩短率基本相似。移植术后4周,正常对照组、单个核细胞组、间充质干细胞组左心室舒张末内径均明显低于模型组(F=4.68,P=0.01),左心室射血分数及短轴缩短率均明显高于模型组(F=5.14,P=0.01;F=3.32,P=0.04),各组左心室收缩末内径差异无显著性意义(F=1.64,P=0.21)。②心肌组织病理学改变:电镜下单个核细胞组、间充质干细胞组在梗死边缘区可见有胶体金颗粒的不成熟的心肌细胞,胞质中散在肌丝结构,肌丝排列紊乱不规则。③心肌组织核转录因子кB阳性率表达:与模型组比较,单个核细胞组、间充质干细胞组的梗死边缘区核转录因子кB阳性率明显降低(F=25.59,P=0.0001);正常心肌区核转录因子кB阳性率亦明显降低(F=18.20,P=0.0001)。④心肌细胞凋亡检测结果:与模型组比较,单个核细胞组、间充质干细胞组在心肌梗死区细胞凋亡率均明显降低(F=6.63,P=0.0027),梗死边缘区细胞凋亡率亦明显降低(F=36.07,P=0.0001)。正常心肌区单个核细胞组细胞凋亡率与模型组基本相似(F=9.69,P=0.004),但间充质干细胞组有所降低。⑤心功能与心肌细胞凋亡及心肌组织NF-кB的相关性:急性心肌梗死4周时,左心室射血分数与心肌细胞凋亡、心肌组织核转录因子кB均呈负相关(r=0.613,P=0.001;r=-0.437,P=0.033)。心肌细胞凋亡与心肌组织核转录因子кB呈正相关(r=0.672,P=0.002)。结论:经冠脉移植骨髓单个核细胞和间充质干细胞均可改善实验性急性心肌梗死动物的心功能,与梗死边缘区核转录因子кB表达降低及心肌细胞凋亡减少有关。骨髓单个核细胞移植的促血管增生作用优于间充质干细胞移植。 相似文献
40.
Lipogenesis in subcutaneous abdominal adipocytes during late human pregnancy was investigated by studying insulin receptor binding, 3-O-methyl-(14C-(U]-glucose flux and incorporation of (14C(U]-glucose into CO2 (oxidation) and total lipids (lipogenesis) in adipocytes from 18 health pregnant women undergoing Caesarean section at term, and 19 non-pregnant women undergoing gynaecological surgery. The cell diameter and fasting insulin were increased in the pregnant women, compared with controls (P less than 0.01 and P less than 0.05, respectively). The insulin receptor binding, 3-O-methyl-glucose flux, and basal oxidation were similar in both groups. Basal lipogenesis was higher in adipocytes from pregnant women than from controls (P less than 0.05), but the maximally stimulated increment was similar in both groups. Basal and maximally stimulated lipogenesis correlated positively with the cell diameter (P less than 0.001 and P less than 0.05, respectively). The findings indicate that lipogenesis in subcutaneous abdominal adipocytes from pregnant women is increased due to post-receptor events and that adipocytes do not contribute to the insulin resistance in late pregnancy. 相似文献