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31.
Intra-articular ganglia are rare and mostly incidental findings on magnetic resonance imaging (MRI) and arthroscopy. We present 4 cases of intra-articular ganglion cysts associated with the anterior cruciate ligament (ACL) in 3 patients. The most commonly occurring symptoms were pain aggravated after stressing activities and limited knee range of motion. In 1 patient, ganglion cysts appeared in both knees with a time difference of 1 year. An MRI revealed typical signs of ganglion cysts in the substance of the ACL. Arthroscopy was performed for further evaluation and treatment. Histologic examination of the tissue removed revealed the presence of features consistent with ganglion cysts. Therefore, in the case of chronic knee discomfort with nonspecific clinical signs and symptoms and without a clear cause, an intra-articular ganglion cyst should be considered as causing pathology. An MRI is the most sensitive and specific method for diagnosis. However, the relatively slow progression of symptoms may delay the patient’s decision to seek medical attention. Delayed diagnosis makes arthroscopic total resection of the ganglion technically demanding or not possible at all, and extensive debridement of the ACL may be required.  相似文献   
32.
Antioxidant defence during cardiopulmonary bypass surgery.   总被引:1,自引:0,他引:1  
OBJECTIVE: Cardiac surgery may lead to severe oxidative stress due to formation of oxidation products generated during ischemia and reperfusion. We investigated to which extent oxidative stress influences a number of endogenous antioxidants and markers of cellular activation. METHODS: At six time points blood was withdrawn from patients undergoing coronary artery bypass grafting, using the on-pump procedure. RESULTS: Both glutathione peroxidase and superoxide dismutase show a gradual and strong increase in activity during surgery (40 and 30%, respectively), returning to baseline values 24 h after surgery. The total antioxidant capacity has a maximum increase of 60%. Markers of cellular activation, such as eosinophil cationic protein and tryptase also increase during the procedure. CONCLUSION: Cardiac surgery results in systemic inflammation accompanied or caused by severe oxidative stress. The human body has a strong innate oxidative defence screen, which is probably not sufficient to fully compensate for the total amount of oxidative damage.  相似文献   
33.
OBJECTIVE: The purpose of this presentation is to show the imaging findings of the common and uncommon variants of adenomyosis as seen on sonography and magnetic resonance imaging (MRI). METHODS: A 3-year database search was performed to identify women who had pelvic sonography and pelvic MRI within a 6-month interval. Images of these cases were retrospectively reviewed. RESULTS: Eighty women were identified. Adenomyosis was diagnosed on MRI, which was used as the reference standard, in 45 of these women. The correct diagnosis was made on sonography in 73% of the cases. CONCLUSIONS: Awareness of the spectrum of imaging features of adenomyosis is important to use sonography effectively for diagnosing this entity and to help avoid misdiagnosis.  相似文献   
34.
In vivo diagnosis with cancer-specific targeting agents that have optimal characteristics for imaging is an important development in treatment planning for cancer patients. Overexpression of the HER2 antigen is high in several types of carcinomas and has predictive and prognostic value, especially for breast cancer. A new type of targeting agent, the Affibody molecule, was described recently. An Affibody dimer, His6-(ZHER2:4)2 (15.4 kDa), binds to HER2 with an affinity of 3 nmol/L and might be used for the imaging of HER2 expression. The use of 99mTc might improve the availability of the labeled conjugate, and Tc(I)-carbonyl chemistry enables the site-specific labeling of the histidine tag on the Affibody molecule. The goals of the present study were to prepare 99mTc-labeled His6-(ZHER2:4)2 and to evaluate its targeting properties compared with the targeting properties of 125I-4-iodobenzoate-His6-(ZHER2:4)2 [125I-His6-(ZHER2:4)2]. METHODS: The labeling of His6-(ZHER2:4)2 with 99mTc was performed with an IsoLink kit. The specificity of 99mTc-His6-(ZHER2:4)2 binding to HER2 was evaluated in vitro with SK-OV-3 ovarian carcinoma cells. The comparative biodistributions of 99mTc-His6-(ZHER2:4)2 and 125I-His6-(ZHER2:4)2 in tumor-bearing BALB/c nu/nu mice were determined. RESULTS: The labeling yield for 99mTc-His6-(ZHER2:4)2 was approximately 60% (50 degrees C), and the radiochemical purity was greater than 97%. The conjugate was stable during storage and under histidine and cysteine challenges and demonstrated receptor-specific binding. The biodistribution study demonstrated tumor-specific uptake levels (percentage injected activity per gram of tissue [%IA/g]) of 2.6 %IA/g for 99mTc-His6-(ZHER2:4)2 and 2.3 %IA/g for 125I-His6-(ZHER2:4)2 at 4 h after injection. Both conjugates provided clear imaging of SK-OV-3 xenografts at 6 h after injection. The tumor-to-nontumor ratios were much more favorable for the radioiodinated Affibody. CONCLUSION: The use of Tc(I)-carbonyl chemistry enabled us to prepare a stable, site-specifically labeled 99mTc-His6-(ZHER2:4)2 conjugate that was able to bind to HER2-expressing cells in vitro and in vivo. The indirectly radioiodinated conjugate provided better tumor-to-liver ratios. The labeling of Affibody molecules with 99mTc should be investigated further.  相似文献   
35.
OBJECTIVES: Assessment of morphological characteristics of lymphnodes studied ex-corpore by echoendoscopy--shape, sharpness of limits, echogenicity and dimensions--to categorize them either as metastatic or non-metastatic. MATERIAL AND METHODS: Fifty-four lymphnodes were studied. They were identified and studied by echoendoscopy in fresh surgical specimens of oesophagus, stomach and rectum. Eight nodal characteristics were evaluated. The data obtained were studied by multivariate analysis using the logistical estimate method in two different statistical models. RESULTS: In model 1, logistical estimate demonstrated that well-defined limits (WDL) of the lymphnodes and the association of hypoechogenicity and round shape were the most significant variables suggesting the presence of invasion. In model 2, the most significant variables were WDL, round shape and association of round shape with WDL. The first model had a high sensitivity of 93.1% and specificity of 68% whereas the second model had a greater specificity of 84%, with a slight fall in sensitivity. CONCLUSION: These models might have an application to clinical practice particularly in the pre-operative assessment of patients with oesophageal carcinoma, gastric carcinoma or rectal carcinoma.  相似文献   
36.
Failure to retain health professionals in rural areas contributes to the poor health status of these communities through an inability to deliver reliable and consistent services. Considerable attention has been focused on factors affecting recruitment of health professionals. Far less is known about factors affecting the retention of occupational therapists. This was the focus of this study. Ethnographic interviews were used to explore the experiences of 10 occupational therapists who had left rural practice. Six themes emerged from the participants' experiences, from when they first considered rural practice to reflections following their departure from it. These themes were initial appeal, facing the challenge, rural practice issues, the social sphere, reasons for leaving and the value of rural experience. These factors gave rise to a proposed Model of Retention Equilibrium, which suggests that retention can be improved by addressing the imbalance between incentives to leave and incentives to stay. The model provides a useful framework for occupational therapists contemplating rural practice, as well as for health services managers responsible for service delivery in rural areas.  相似文献   
37.
Abstract Facial gingival surfaces of maxillary and mandibular anterior teeth were monitored to evaluate changes of the width of the keratinized and attached gingiva. 96 children 6 to 12 years of age were examined 2 × with an interval of 2 years. Measurements included dental plaque, gingival inflammation, probing depth, and width of keratinized and attached gingiva. In addition, study models were used to determine the facial/lingual position of the teeth. The results of this report, evaluating well-aligned teeth only, showed that during the 2-year observation period, increases in widths of the facial keratinized and attached gingiva took place. Increases occurred for the various teeth regions examined, and for deciduous as well as permanent teeth. During transition from the deciduous to the permanent dentition, patterns of change were variable. The increase of gingival widths was greatest for sites with the smallest baseline width of attached gingiva, and smallest for sites with the greatest baseline width. It was concluded that in well-aligned teeth, a conservative, monitoring approach prior to a corrective, surgical intervention seems prudent in children of this age with a minimal zone or absence of attached gingiva.  相似文献   
38.
The phase equilibrium of plasticized polymer systems on the basis of cellulose diacetate and ethylene glycol esters of dibasic aliphatic acids (from oxalic acid to 1,10-decanedicarboxylic acid) was studied and the solubility parameters and the thermodynamic interaction parameters of the components were calculated. It is shown that an increase in molecular weight of the plasticizers leads to a lower miscibility of the components, a fact which is reflected in a regular rise of the upper critical solution temperature (UCST), a tendency of the systems for gelation, a decrease of the solubility parameter of the plasticizer δ1, and a growth of the interaction parameters χH and χ12. The results are discussed in terms of the existing theories for polymer solutions.  相似文献   
39.
Immunology     
A selection of interesting papers that were published in the two months before our press date in major journals most likely to report significant results in immunology.  相似文献   
40.
薛安娜  陈孝曙 《卫生研究》1994,23(3):150-152
测定分析不同膳食特点地区975例年龄45~74岁中老年人的血红蛋白及其与膳食营养素的关系。结果牧民及城市居民贫血率低,北京及新疆托里分别为7.6%和4.6%。男性比女性血红蛋白高,血红蛋白随年龄增加而降低。相关分析结果血红蛋白与膳食热能、蛋白质、动物蛋白质与总蛋白质比值呈显著正相关。结果说明血红蛋白可用于中老年人营养状态监测。  相似文献   
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