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81.
To study interactions of head and eye during various motor tasks in a clinical environment, a recording system is needed which should be characterized by high precision and reliability. A computer-assisted optoelectronic method based on the SELSPOT system is described. All the equipment was specially designed for neuro-ophthalmologic purposes and fulfills the requirements. A range of programs was developed using several types of signal processing algorithms, allowing simultaneous one-dimensional and two-dimensional representation of motor acts of the head and eye, including separate analysis of slow and rapid movements. Thus, the method is suitable for analyzing physiologic and pathologic mechanisms of complex interactions. The quality of this novel SELSPOT application is demonstrated by recordings made during induced circular movements.  相似文献   
82.
83.
We report on a man without any symptoms until the age of 29 years when a ventricular tachyarrhythmia occurred for the first time. There were electrocardiographic signs of a previous myocardial infarction of the anterior wall, but there had not even been any episode of angina pectoris. The cause was the anomalous origin of the left coronary artery from the pulmonary trunk (Bland-White-Garland syndrome). Therapy consisted of ligation of the left coronary artery and the implantation of an aortocoronary vein graft to the left coronary artery in order to reinstall a two-coronary system. Diagnosis is easily made by coronary angiography. At a 3-year follow-up there was an increase of the ejection fraction/cardiac output, a stable sinus rhythm, and an improved physical endurance.  相似文献   
84.
A strain of Streptococcus sanguis that induced rabbit platelets to aggregate in vitro (Agg+ phenotype) was hypothesized to be a more virulent pathogen than an Agg- strain in experimental endocarditis in rabbits. A left ventricular catheter was implanted, and then an Agg+ or Agg- strain was inoculated intravenously. Vegetations formed on the aortic semilunar valves but were unaffected by the duration of implantation of the catheter. Vegetations enlarged by accumulating platelets and their mass increased directly with the duration of endocarditis. Inoculation of the Agg+ strain consistently caused endocarditis with significantly larger vegetations, a more severe clinical course (including febrile episodes, hematological changes, and signs of myocardial ischemia), more gross lesions in major organs, and greater mortality than inoculation with the Agg- strain, saline, or the Agg+ strain pretreated with monospecific rabbit immunoglobulin G or Fab fragments against its platelet aggregation-associated protein (PAAP; class II). In experimental endocarditis, PAAP expressed by Agg+ S. sanguis appeared to be an important virulence factor.  相似文献   
85.
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   
86.
A patient known with acute intermittent porphyria who developed primary liver-cell carcinoma is described. No other risk factors were found. A possible association of acute intermittent porphyria with the development of primary liver-cell carcinoma has been suggested in recent, mainly Scandinavian literature. So far this association has never been described in The Netherlands.  相似文献   
87.
During the 30-month period from March 1, 1988, through August 31, 1990, image-guided aspirations of 183 solitary occult breast masses, which were considered possible cysts, were performed. Indications for aspiration included (1) mass on mammography, either invisible on ultrasonography or with features atypical of a cyst, in 111 patients; (2) enlarging solitary mass on mammography with ultrasonic features suggesting a cyst in 45 patients; and (3) mammographic mass with features typical of a cyst in 27 patients, with confirmation requested by the referring physician. Of the group, 151 (83%) lesions were fluid-filled and 32 (17%) were solid. All aspirates had normal cytologic features. Of the 32 aspirates found to be solid, 19 were subsequently removed after wire localization and 13 were unchanged on mammography for a minimum of 6 months after aspiration. This is a simple and safe procedure, confirming the innocuous nature of an occult solitary breast cyst, and obviates the need for surgical biopsy.  相似文献   
88.
Cochlear implantation is a treatment for profound bilateral cochlear hearing loss. Two broad varieties of cochlear implants are used: single or multichannel device (22- channel) inserted either into the cochlea (tympanic ramp) or on the promontory on round window Imaging modalities have to predict cochlear patency prior surgery, an essential factor for choosing between intra or extra cochlear implant. Since March 1991, we have investigated 23 implant candidates to evaluate cochlear patency prior surgery, 6 patients underwent surgery: 4 had a multichannel and 2 had a monochannel electrode. Both CT and MRI play a role in pre operative study. CT easily predicts cochlear ossification and labyrinthine malformations MRI (3 D applications) with T 2 Weighted images, one millimeter thick, more clearly depicts labyrinthine liquid and can predict cochlear fibrosis before ossification.  相似文献   
89.
The Kasabach-Merritt syndrome is characterized by thrombocytopenia and localized coagulopathy associated with a hemangioma. Most techniques applied to eradicate the tumor or accelerate its involution (surgery, radiation therapy, embolization) are invasive and require transfusion of large amounts of blood products. In some cases, medical treatment is the only alternative. Efficacy of steroids and antifibronolytic agents has already been described, but even this approach is associated with the administration of blood products. We report two cases of infants with Kasabach-Merritt syndrome associated with cardiac and hepatic hemangiomas. At admission, both had signs of cardiac failure. They were successfully treated with prednisone and epsilon-aminocaproic acid (EACA). Blood products were not required once the diagnosis was made. These observations have important implications for the management of patients with Kasabach-Merritt syndrome because they show that even in severe cases blood transfusions can be avoided by the use of prednisone and EACA.  相似文献   
90.
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