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981.
观察329块(男193,女136)国人成年跟骨的距关节面形态。其中A型出现率,男为45.08±3.58%,女为41.18±4.22%;B型出现率男为53.89±3.59%,女为58.82±4.22%;C型仅男性出现2例,占1.04±0.73%。成套标本中,距关节面左右对称的,男性90例中有81例,占90.00±3.16%;女性67例中有59例,占88.06±3.96%。经统计学处理,侧别间及性别间均无明显差异。文内结合观察结果提出自己的分型标准及类型,并与以往资料进行了比较。  相似文献   
982.
为探讨药效法估测的效应消除半衰期和效量法估测的表观半衰期对合理制订给药方案的意义和作用,以桂枝汤解热和抗炎的药物动力学实验中所得的相应参数值设计了给药方案,观察了它们在提高药效上的作用。结果表明在给药总剂量相等、首次给药同时开始的情况下,以半衰期设计的给药方案组的药效均明显高于习惯的一次给药组;而以效应消除半衰期设计给药方案组药效增强率又高于以表观半衰期设计的方案组。提示效应消除半衰期比表观半衰期似更有实践意义。  相似文献   
983.
Summary The effectiveness of a surveillance program for breast cancer recurrence in extending survival is predicated on two assumptions: 1) most recurrences are detected at an early stage at surveillance visits; and 2) the early treatment of recurrence offers a better chance of cure or longer survival. However, the data suggest that neither of these two assumptions is correct, and that postoperative follow-up of patients with breast cancer is expensive and does not significantly extend survival.This minisymposium was presented December 8, 1992, at the annual San Antonio Breast Cancer Symposium, and was sponsored by educational grants from Amgen and from Bristol-Myers Oncology Division.  相似文献   
984.
33例肝占位性病变MRI误诊的分析   总被引:1,自引:0,他引:1  
我院1988年以来4000余例腹部MRI中,发现肝占位性病变误诊33例。所用机型为美国Disonics公司0.5T超导MRI,自旋回波序列(SE序列)、常规T1加权(T1WI)、质子加权(PDWI)、T2加权(T2WI),覆盖全肝。其中,PHC误诊为MHC5例、MHC误诊为PHC6例、PHC误为HHE5例、MHC误诊为HHE2例、HHE误诊为PHC6例、肝硬化结节误诊为PHC2例、炎性假瘤误诊为PHC3例、肝结核误诊为PHC1例、HCY误诊为HHE3例。本文从病变的影像学特征和扫描技术方面详细探讨了误诊的原因和鉴别诊断要点。  相似文献   
985.
低温体外循环下手术治疗主动窦瘤破裂16例,采用右房切口1例,右室流出道切口11例,窦瘤破入腔和主动脉根部双切口4例。单纯窦瘤破口修补2例;双头垫片针窦瘤基部与空间隔踬同并列间断褥式缝合修补3例;  相似文献   
986.
987.
Lung function, smoking, age and mortality data in 158 adult severe alpha1-antitrypsin deficient, PiZZ individuals, followed from 1963 to 1982 were analyzed. Low initial FEV1 value was significantly associated with increased mortality (p < 0.005). A 3 yr mortality rate of 40% was found in individuals whose initial FEV1 values were less than 30% of that predicted. In contrast, the corresponding 3-yr mortality among those whose initial FEV1 values were between 30 and 65% of that predicted was only 7%. Smokers were found to have significantly lower FEV1 levels (p = 0.008) and higher mortality (p < 0.005) than non-smokers. The difference between current and ex-smokers in mortality and FEV1 level were not statistically significant (p = 0.9 and p>0.25, respectively). Cross-sectional analysis of the initial FEV1 values indicated a significant decline (p < 0.005) of FEV1 with increasing age. This decline was greater among smokers than non-smokers. Longitudinal analysis of FEV1 rates of decline in 80 cases with follow-up FEV1 measurements failed to detect any significant differences between smokers and non-smokers, but was performed late in the disease process. The application of these results to the planning of studies on replacement therapy, smoking intervention strategy and longitudinal follow-up is discussed.  相似文献   
988.
二乙基二硫代氨基甲酸钠驱镍作用的实验研究   总被引:1,自引:0,他引:1  
本文用大鼠研究了带-SH基的二乙基二硫代氨基甲酸钠(Dithiocarb,简称Na-DDC或称铜试剂)和不带-SH基的新螯合剂(H-73-10)的驱镍作用。结果表明,Na-DDC对羰基镍(Ni(CO)_4〕的驱镍作用明显优于H-73-10;与此相反,H-73-10对硝酸镍〔Ni(NO_3)_2〕染毒大鼠的驱镍作用却明显优于Na-DDC。  相似文献   
989.
To determine if transforming growth factor alpha (TGFα) pretreatment protects hair cells from aminoglycoside induced injury by modifying their intracellular calcium concentration, we assayed hair cell calcium levels in organ of Corti explants both before and after aminoglycoside (i.e. neomycin, 10−3M) exposure either with or without growth factor pretreatment. After TGFα (500ng/ml) treatment, the intracellular calcium level of hair cells showed a five-fold increase as compared to the levels observed in the hair cells of control cultures. After ototoxin exposure, calcium levels in hair cells of control explants showed an increase relative to their baseline levels, while in the presence of growth factors pretreatment, hair cells showed a relative reduction in calcium levels. Pretreatment of organ of Corti explants afforded significant protection of hair cell stereocilia bundle morphology from ototoxic damage when compared to explants exposed to ototoxin alone. This study correlates a rise in hair cell calcium levels with the otoprotection of hair cells by TGFα in organ of Corti explants.  相似文献   
990.
Summary Human fibrin glue (Tissucol) is a plasma-derived compound endowed with adhesive and hemostatic properties and possessing a specific local anti-infection function mediated through activation of nonspecific immunity elements. The aim of this study is to show that in patients who have undergone prolonged reconstructive plastic surgery following cancer resection, Tissucol decreases infectious complications as compared to a control group. Between June 1985 and February 1988, 51 subjects were treated with fibrin glue during reconstruction operations. Analysis of the results showed that Tissucol produced a statistically significant reduction both of immediate complications, such as inflammation and partial separation of the surgical wound, and of delayed complications, such as scar hypertrophy and cutaneous fistulae. In conclusion, patients treated with Tissucol showed a better quality of surgical wound, a more rapid postoperative functional recovery and consequently a decrease in the duration of hospitalization.  相似文献   
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