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81.
Wang KY; Kimmey MB; Nyberg DA; Mack LA; Haggitt RC; Shuman WP; Franklin DW; Silverstein FE 《Radiology》1987,165(3):827-829
Six normal and 16 neoplastic colorectal specimens were examined with 8.5-MHz ultrasound (US). An articulated system facilitated precise spatial correlation between US and histologic sections. Images were blindly interpreted and then compared with histologic results. All six normal specimen showed five distinct echo layers and were distinguished from neoplastic specimens by all the observers. The central echogenic layer, corresponding to the submucosa, is useful in determining the depth of origin of a neoplasm and the presence of submucosal invasion. US had an accuracy of 92.5% in demonstrating invasion of the submucosa and 77% for invasion of the muscularis externa. For mucosal neoplasms with invasion through the muscularis externa and extension into the subserosal tissues, nearly 90% of US interpretations were correct. High-frequency US may be useful in determining the depth of invasion of mucosal tumors with respect to the submucosa and in differentiating mucosal from extramural masses. 相似文献
82.
Urine-compatible polymer for long-term ureteral stenting 总被引:1,自引:0,他引:1
Internal double-J ureteral stents were designed from a urine-compatible polymer (C-Flex), and 35 stents were placed in patients. The overall patency rate for the stents was 80%, with most stent failures occurring before 2 months; the follow-up period ranged from 2 to 16 months, with a mean follow-up for all stents of 5.0 months. Stents were considered patent at last follow-up only if they had been in place for at least 2 months. No migration or fracture of the stents occurred. Physical properties of urine-exposed stents were compared with those of virgin tubing and tubing exposed for 1 year to shelf conditions. Stent patency was optimized by increasing urine flow by increasing the patient's voluntary oral intake, administering prophylactic oral antibiotics, and avoiding placement of stents into grossly bloody or infected collecting systems. 相似文献
83.
Meniscal tears of the knee: accuracy of MR imaging 总被引:39,自引:0,他引:39
Before surgery, 277 menisci in 144 knees were examined with magnetic resonance (MR) imaging. They were then examined directly with arthroscopy or arthrotomy. Menisci were graded on a scale of 1-3 according to the character of the intrameniscal MR imaging signal. At surgery, 137 of 154 (89%) menisci exhibiting only grade 1 or grade 2 signal were found to be normal. One hundred sixteen of 123 (94%) menisci exhibiting intrameniscal signal communicating with a meniscal articular surface (grade 3 signal) had tears. If only a grade 3 signal is considered consistent with meniscal tears, then MR findings and surgical findings agreed in 91.3% of menisci. MR imaging can separate surgically significant from nonsignificant meniscal lesions and is useful in the noninvasive preoperative screening of suspected meniscal tears. 相似文献
84.
85.
商陆多糖Ⅱ体外对小鼠脾细胞增殖及产生集落刺激因子的影响 总被引:10,自引:0,他引:10
用[3H]TdR参入法检测小鼠脾细胞增殖能力及产生集落刺激因子(colony stimulating factor. CSF)含量.证明商陆多糖Ⅱ(PAP-Ⅱ)在31~500 μg·m-1范围内显著促进小鼠稗细胞增殖。PAP-Ⅱ,31~125 μg·ml-1可剂量依赖性地促进Con A(1,2.8μg·ml-1),LPS(3,10,30 μg·ml-1)诱导的淋巴细胞细咆增殖,随着PAP-Ⅱ剂量加大,对丝裂原诱导的淋巴细胞增殖反呈抑制作用。PAP-Ⅱ。10~500μg·ml-1呈剂量及时间依赖性地促进脾细胞产生CSF,其最适剂量为100 μg·ml-1。最佳时间为5 d,提示PAP-Ⅱ能增强免疫及促进造血功能。 相似文献
86.
87.
Early life and later determinants of adult disease: a 50 year follow-up study of the Newcastle Thousand Families cohort 总被引:2,自引:0,他引:2
DW Lamont Dr L Parker MA Cohen M White SMA Bennett NC Unwin AW Craft KGMM Alberti 《Public health》1998,112(2):85-93
The relative contribution of socioeconomic, behavioural and biological factors operating in fetal and infant life, childhood and adulthood to risk for cardiovascular disease, respiratory diseases and non-insulin-dependent diabetes in middle age has become an important research issue. All 1142 babies born in Newcastle upon Tyne in May and June 1947 were recruited into a prospective cohort study of child health (the ‘Thousand Families’ study) and followed in great detail to the age of 15 y, with a brief further follow up at age 22 y. Children from poorer families were at greatest risk of severe respiratory tract infection in infancy. Children from professional and managerial families were on average taller and heavier throughout childhood than those from semi- and unskilled manual social classes. Repeated infections in early childhood greatly increased the risk of developing chronic respiratory disease by age 15 y. This paper outlines a new investigation designed to trace surviving members of this cohort and to chart the relationships between their socioeconomic circumstances, lifestyles, experiences and health from birth through to the present day. Existing data on socioeconomic circumstances and infections in infancy and childhood, infant nutrition, birthweight and physical development to age 22 y will be linked to information gained from a new study. This comprises a postal questionnaire survey of study members' adult health, socioeconomic circumstances and lifestyle, and a hospital based clinical examination including heart and lung function, glucose tolerance, blood lipids and anthropometric measurements at age 49–51 y. Out of a target sample of 979 people for whom sufficient data are available on the first year of life, 866 (88%) have been traced and 649 are still resident in the North of England. Those study members who have been traced are highly representative of the original cohort. The Thousand Families cohort provides a unique opportunity for detailed epidemiological study because of the wealth of data available on infant and childhood socioeconomic and family circumstances, all of which was collected prospectively. In addition, there has been comparatively little loss to follow-up since 1948. 相似文献
88.
R A Rusnak 《Emergency Medicine Clinics of North America》1989,7(4):903-925
Although loss of normal pituitary function may be silent and asymptomatic, sudden loss of gland function (pituitary apoplexy) typically results in characteristic presentations. Sheehan's syndrome is the development of hypopituitarism after postpartum hemorrhage or shock. Patients with Sheehan's syndrome may have typical or atypical presentations based on the extent of pituitary gland destruction. Patients with typical symptoms fail to lactate after giving birth; subsequently these patients also develop symptoms and signs of hypopituitarism. Measuring the serum prolactin level after giving thyrotropin-releasing hormone is a reasonable first step in the diagnosis of this condition in patients who fail to lactate after giving birth. The diagnosis of hypopituitarism is delayed for up to 7 years in patients with atypical symptoms. Acute symptomatic failure of the pituitary gland (pituitary apoplexy) commonly occurs in patients who have asymptomatic pituitary tumors. Many patients with pituitary tumors do not have signs of abnormal endocrine gland secretion and have a normal appearance. Most patients have the following signs or symptoms: headache; acute disturbances in visual acuity or visual fields; ophthalmoplegia, and changes in the level of consciousness. The syndrome of pituitary apoplexy usually evolves over hours to days. Subarachnoid hemorrhage and acute bacterial meningitis are the two most important mimics of pituitary apoplexy. Intravenous steroids and prompt neurosurgical consultation are mandatory in cases of pituitary apoplexy since both steroids and surgery can improve vision. Testings for acute or chronic hypopituitarism is challenging in the Emergency Department setting; however, carefully chosen tests will aid in the subsequent early correct diagnosis after initial Emergency Department management. 相似文献
89.
Multiphasic examinations of 153 gastric abnormalities observed radiologically and endoscopically were reviewed to determine the efficacy of four radiologic techniques and of several common combinations of these techniques for examining the stomach. There were 68 gastric ulcers, 12 ulcer scars, 44 cases of gastritis including 27 with erosions, 24 benign neoplasms, and five malignancies. Double-contrast, compression, mucosal relief, and full-column techniques detected 82%, 65%, 62%, and 51%, respectively, of all lesions diagnosed with the complete multiphasic examinations. Results indicate that the greater the number of techniques employed, the more accurate the examination, with biphasic and multiphasic examinations detecting 9%-18% more lesions overall than simple single- or double-contrast studies. 相似文献
90.
Immunosuppressants implicate protein phosphatase regulation of K+ channels in guard cells. 总被引:22,自引:5,他引:17 下载免费PDF全文
S Luan W Li F Rusnak S M Assmann S L Schreiber 《Proceedings of the National Academy of Sciences of the United States of America》1993,90(6):2202-2206
The elevation of Ca2+ levels in the cytoplasm inactivates inward-rectifying K+ channels that play a central role in regulating the apertures of stomatal pores in higher plants. However, the mechanism for the Ca(2+)-mediated inhibition of K(+)-channel function is unknown. Using patch-clamp techniques, we show that cyclophilin-cyclosporin A and FK506-binding protein-FK506 complexes, which are highly specific inhibitors of protein phosphatase 2B (calcineurin), block Ca(2+)-induced inactivation of K+ channels in Vicia faba guard cells. A constitutively active calcineurin fragment that is Ca(2+)-independent inhibits K(+)-channel activity in the absence of Ca2+. We have also identified an endogenous Ca(2+)-dependent phosphatase activity from V. faba that is inhibited by the cyclophilin-cyclosporin A and FK506-binding protein-FK506 complexes. Our findings implicate a Ca(2+)-dependent, calcineurin-like protein phosphatase in a Ca2+ signal-transduction pathway of higher plants. 相似文献