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111.
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
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113.
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
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115.
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
116.
OBJECTIVE: We attempted to determine a valid pharmacological approach for the control of high blood pressure in obese hypertensive patients using two antihypertensive agents with different pharmacological actions. DESIGN: Thirty-two obese hypertensive black women were randomly treated with chlorthalidone or clonidine to achieve adequate blood pressure control. Unresponsive patients received combination therapy with both agents. RESULTS: Twenty-nine patients completed the study. Systolic and diastolic blood pressures were reduced with both agents, more so with chlorthalidone. Of the 15 patients treated with chlorthalidone, 14 had satisfactory reduction in diastolic pressure compared with only four of the 14 treated with clonidine. Of the 11 unresponsive patients treated with combination therapy, 10 achieved satisfactory control of blood pressure. CONCLUSIONS: We conclude that a rational approach to the treatment of hypertension in obese black women includes diuretics, a first choice attempt that tries to address the hemodynamic alterations previously identified in those patients. Combining diuretics with an alpha-adrenergic agonist resulted in complete control of blood pressure in most of the hypertensive patients in our study. The lowest dose of each antihypertensive medication, especially when used in combination, was effective in a high percentage of patients. The use of this antihypertensive approach also helps to clarify which of the underlying pathophysiological mechanisms should be targeted when other currently available antihypertensive medications are used. 相似文献
117.
Introduction: Epidural blood patches (EBPs) usually afford rapid and successful treatment outcomes for postdural puncture headaches (PDPH) with few adverse sequelae. Patients and Methods: In order to identify potential risk factors for any adverse outcomes of EBP, a Medline search, 1966 to the present, of case reports and series of any adverse outcomes following EBP for PDPH was conducted. The literature search identified 26 patient cases with 21 cases defined as adverse neurological outcomes, and further stratified as compression or noncompression syndromes, and five cases defined as persistent cranial nerve (CN) palsies. Cases were also stratified by age, sex, and blood volumes of EBP or delays in administration, and compared for statistically significant differences in continuous variables by unpaired, two‐tailed t‐tests and for significant correlations between predictor variables, including EBP volumes and delays in administration, and adverse neurological outcomes, by simple linear regression analysis. Results: There were no statistically significant sex differences in the mean ages or weights of the study population, or in the total volumes of autologous blood injected in EBPs. When the study population was compared for adverse neurological outcomes by compression or noncompression syndromes, patients experiencing compression syndromes received significantly more EBP volumes (35.36 mL) than patients experiencing noncompression (17.46 mL) syndromes (P = 0.025). Regression analysis confirmed a significant direct linear relationship between increasing EBP volumes and worsening adverse neurological outcomes (P = 0.008). In patients with CN palsies associated with PDPH and unrelieved by EBP, regression analysis again confirmed significant direct linear relationships between increasing days waited to perform EBP and increasing duration of CN palsies in months (P = 0.001). Conclusions: Epidural blood patches for the management of PDPH, especially PDPH associated with CN palsies, should be administered as soon as the diagnosis of PDPH is made with lower volumes of autologous blood (≤20 mL) to assure the best treatment outcomes. 相似文献
118.
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
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120.
Vertebrates employ V(D)J recombination to generate diversity for an adaptive immune response. Born of a transposon, V(D)J recombination could conceivably cause more trouble than its worth. However, of the two steps required for transposon mobility (excision and integration) this particular transposon's integration step appears mostly blocked in cells. The employment of a transposon as raw material to develop adaptive immunity was thus a less-risky choice than it might have been … but is it completely risk-free? 相似文献