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91.
In this study, patients who played tennis after undergoing a total knee arthroplasty were analyzed in terms of their functional abilities and degree of satisfaction. The patients were recruited by means of a questionnaire that was sent to players from lists supplied by the United States Tennis Association. The study group consisted of 28 men and 5 women (46 total knee replacements) with a mean age of 64 years. Only 21% (7 of 33) of the patients' surgeons approved of their patients undertaking tennis activity, with 45% (15 of 33) recommending only doubles tennis. At both 1 year and a mean of 7 years after arthroplasty, players were playing both singles and doubles tennis approximately three times per week (range, one to seven). All tennis players polled were satisfied with their knee arthroplasties and their ability to resume playing tennis. Because the study patients played at a high level, future studies are needed to determine the effect of tennis on the general population, which does not play at such a uniformly high level. The long-term (15 to 20 years) effect of tennis activity on the clinical and radiologic outcome of total knee arthroplasty also needs to be determined.  相似文献   
92.
93.
背景:在亚洲、非洲和欧洲,致病性H5N1流感病毒引起禽流感在家禽和候鸟中爆发流行,还导致了人类发病和死亡。虽然目前H5N1毒株引起人与人之间的传染不太可能,但它仍可能是未来流感大范围流行的潜在威胁因素。本试验的目的就是评价针对H5N1病毒株的裂解病毒疫苗的安全性和免疫原性。方法:对300名志愿者(年龄为18岁~40岁)进行随机、开放标签的、无对照的Ⅰ期试验。300名志愿者被分为6组:7.5mg血凝素加佐剂组(n=50)、7.5mg血凝素不加佐剂组(n=49)、15mg血凝素加佐剂组(n=50)、15mg血凝素不加佐剂组(n=50)、30mg血凝素加佐剂组(n=51)、30mg血…  相似文献   
94.

Background  

To reduce the risk of brain damage children with acute lymphoblastic leukaemia (ALL) are nowadays mainly treated with intrathecal chemotherapy (ITC) instead of central nervous system (CNS) radiation therapy (CRT) to prevent CNS relapse. However, chemotherapy may also lead to cognitive deficits. As growth hormone deficiency (GHD) or impaired growth hormone secretion are frequently found in ALL patients treated with cranial radiation therapy and/or chemotherapy, we hypothesized that GH therapy may reduce cognitive deficits in these patients.  相似文献   
95.
While tobacco smoke has been conclusively identified as a lung carcinogen, there is much debate over which smoke constituent(s) are primarily responsible for its carcinogenicity. Previous studies in our laboratory suggested that highly lipophilic carcinogens are slowly absorbed in the thicker epithelium of the conducting airways, potentially allowing for substantial local metabolism. The bioactivation of polycyclic aromatic hydrocarbons in airway epithelium may, hence, be important in tobacco smoke-induced carcinogenesis. In the present study, the hypothesis of slow absorption and substantial local metabolic activation of highly lipophilic carcinogen in airway epithelium was tested in dogs. A single dose of tritiated benzo[a]pyrene (BaP) dissolved in a saline/phospholipid suspension was instilled in the trachea, just anterior to the carina. At intervals of a few minutes up to 30 min over a 3-h period, blood samples were drawn from the azygous vein, which drains the area around the point of instillation, and from the systemic circulation. Tissue samples were taken at the end of the experiment. The concentration of BaP with depth into the tracheal mucosa was determined with autoradiography. BaP was slowly absorbed into the trachea with a half-time of approximately 73 min, which is consistent with diffusion-limited passage through the epithelium and lead to local doses in the tracheal epithelium that were more than a 1000-fold those of other tissues. The long retention of BaP in the epithelium provided the local metabolizing enzymes with high substrate levels over a long period, resulting in extensive metabolism. At 3 h after the exposure, 23% of the BaP-equivalent activity remained in the tracheal mucosa. Of this fraction, 13% was parent compound, 28% was organic extractable, 31% was water-soluble, and 28-7% of the instilled dose was bound to tracheal tissues. These results explain the tendency of highly lipophilic carcinogens, such as BaP, to induce tumors at the site of entry and, furthermore, indicate that the highly lipophilic components of tobacco smoke and polluted air may be the most important contributors to lung tumors of the conducting airways.   相似文献   
96.
It is an honour to have been asked to contribute to this volume that commemorates the life and work of Spyros Doxiadis. Spyros was, and is still, a vital and stimulating influence on those of us who were fortunate enough to have been his colleague in all phases of his life. My period of closeness to him was when he was working in Sheffield with Ronald Illingworth. At that time (now over 40 years ago) he and Katherine were having their children and my wife and I was having ours. Then words like "bonding" had not become commonplace as today, but the functional patterns of family relationships were something about which we were intensely aware. I particularly remember a summer when we were holidaying on a tidal estuary between Anglesey and Holy Island and recall a moment when Spyros and I were sitting on a grass topped sandbank watching our children and wives at the water's edge "messing around" with a boat. We watched and discussed the beauty of the postures and poses of our womenfolk with the children and the children with each other. It was the memory of that conversation that stimulated me to propose the topic of this essay in Spyros' memory.  相似文献   
97.
A total of 130 short children were included in a French multicentre study and randomized between a control group (group A) and two groups treated with daily subcutaneous injections of GH at doses of 0.7 IU/kg/week (group B) and 1.4 IU/kg/week (group C) for 2 years. Height velocity was significantly increased ( p <0.0005) in groups B and C, with a greater increase in group C than in group B ( p < 0.001). The benefit after 2 years compared with controls was 4.3 cm in group B and 5.9 cm in group C. The rate of bone maturation was not affected by GH therapy. These results led to the conclusion that 2 years of treatment with GH improves final height prognosis in children with short stature secondary to IUGR, and that this effect is dose dependent. The effect on final height has still to be demonstrated.  相似文献   
98.
Colorectal hemangioma: radiologic findings   总被引:1,自引:0,他引:1  
The authors correlated radiographs with the clinical and histologic data of 12 patients with colorectal hemangioma. All patients presented with rectal bleeding, which was chronic in seven. Phleboliths were also visible in seven cases, which correlated with chronic bleeding in five. On barium studies, three masses were soft and three produced rigid narrowing. The atypical features of rigid luminal narrowing, which might mimic a carcinoma, and hypovascularity correlated with chronic bleeding or visible phleboliths, which suggest the correct diagnosis of colorectal hemangioma.  相似文献   
99.
Ocular radioimmunoscintigraphy: sensitivity and practical considerations   总被引:1,自引:0,他引:1  
Ocular radioimmunoscintigraphy was performed in 20 patients using 99mTc-labeled monoclonal antibody 225.28S, F(ab')2 fragments. Radioimmunoscintigraphy was positive in 13 patients and the diagnosis of ocular melanoma was confirmed by enucleation of the eye or clinical follow-up. Scintigraphy was positive in one patient with lymph node metastasis from an ocular melanoma. In six patients immunoscintigraphy was negative. Using this technique a sensitivity of 92.8% was achieved for detecting ocular melanomas. Single photon emission tomography helped to separate the lesions situated in the nasal quadrant of the eye from the adjacent nasopharyngeal activity. With appropriate imaging techniques small tumors of the order of 3 x 5 x 3 mm could be detected clearly.  相似文献   
100.
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