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71.
Summary The essential disturbance in five patients with vertical nystagmus was an inability to generate smooth pursuit eye movements in the direction of the quick phase of their nystagmus. As the cause of this behavior, the authors suggest an asymmetric impairment of the visual input to the pursuit system. This defect causes a directional preponderance of the pursuit system detectable as a continuous drift off target. The drift is interrupted by refoveating saccades, thus resulting in a vertical nystagmus.
Zusammenfassung Fünf Patienten mit Vertikalnystagmus zeigten als wesentliche Störung eine Unfähigkeit, gleitende Folgebewegungen in Richtung der raschen Nystagmusphase auszuführen. Als Ursache dieser Störung nehmen Verff. eine asymmetrische Unterbrechung visueller Zuflüsse zum Folgesystem an. Durch diese Unterbrechung wird das normalerweise bestehende Gleichgewicht im Folgesystem gestört. Es entsteht ein Richtungsüberwiegen im Folgesystem, das sich in einem Abtreiben der Gesichtslinie vom ruhenden Fixierpunkt auswirkt. Dieses Abtreiben wird immer wieder durch Sakkaden korrigiert, so daß ein Nystagmus entsteht.


Supported by the Deutsche Forschungsgemeinschaft, SFB 70, B 4  相似文献   
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This retrospective study compared plate fixation versus pin fixation in 57 patients with rheumatoid arthritis who underwent wrist arthrodesis. Fixation was achieved by using plates in 32 patients and longitudinal pins in 25 patients. Clinical follow-up averaged 29 months (range: 12-57 months) and radiographic follow-up averaged 16 months (range 12-39 months). Union occurred in 97% of the wrists fixed with plates and in 96% of the wrists fixed with pins. There were 6 (19%) complications in the plate group and 7 (28%) complications in the pin group. Three (12%) wrists fixed with pins moved from the immediate postoperative position to a position of relative volar flexion, while radiographs showed no changes in wrist position in the plate group. With both methods, successful arthrodesis stabilized the wrist in a high percentage of patients. Plate fixation offers an excellent alternative method for arthrodesis of the rheumatoid wrist.  相似文献   
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Purpose: Our aim was to examine the potential of the uterine cavity to affect fertilization and early embryo development. Design: A prospective IRB-approved protocol for patients fulfilling study eligibility criteria was used. Methods: Patients studied included those with primary or secondary infertility, aged less than 38 years, with no history of severe male-factor infertility, and with hysterosalpingogram-and laparoscopic-confirmed bilateral proximal tubal occlusion. Superovulation induction was accomplished with a combination of GnRH agonist and menotropins, with serum hormonal and sonographic monitoring. Within 24 hr prior to, and again at the time of, ovulatory hCG administration, progesterone (P4) was given. Sonographic-guided transvaginal retrieval was performed 35 hr after hCG. Between four and six oocytes were returned to the uterine cavity, admixed with sperm, immediately following retrieval. Luteal support consisted of daily P4 administration. Results: Of the 20 patients recruited for the study, all completed the retrieval and transfer procedure. A total of four clinical pregnancies was achieved, with one early first-trimester loss, one late first-trimester loss (Trisomy 14), and two healthy term infants delivered. IVF of surplus oocytes demonstrated a 82.5% fertilization rate and 66.7% cleavage following cryopreservation. Conclusions: Human fertilization can be achieved through direct uterine transfer of gametes. Furthermore, administration of P4 prior to the ovulatory dose of hCG is compatible with in vitro or in vivo fertilization and implantation.  相似文献   
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PURPOSE: Processes of fibrosis, wound healing and tissue regeneration have in common the fact that proliferation and differentiation of cells involved in the restoration of normal-tissue architecture resemble to a certain degree the embryonic development of the corresponding tissue. The present review focuses on the phenotypic changes of alveolar epithelial cells during fibrogenesis and describes similarities in the expression pattern of epithelial antigens during lung development. METHODS: For comparative studies, immunohistochemical investigations of different experimental fibrosis models were performed. RESULTS: For several epithelial proteins, such as the CD44 adhesion molecule, the enzymes carbanhydrase II and cathepsin D, as well as the lectin galectin-3, a transient epithelial immunoreactivity have been detected. What all four examples have in common is that a part of the foetal antigenic profile reappears under conditions of injury and during the development of pulmonary fibrosis. CONCLUSIONS: The re-expression of foetal antigens in fibrotic samples with a spatio-temporal pattern, as detected by immunocytochemical techniques, indicates that some mechanisms or factors exist, which similarly regulate the differentiation of the epithelium during ontogenesis and in the remodelling process during fibrogenesis.  相似文献   
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127 patients with aneurysmal subarachnoid haemorrhage (SAH) were analyzed for the relationship between the amount of blood clots as detected by initial computed tomography (CT) up to 48 hours after SAH and changes of blood flow velocities as measured using transcranial Doppler ultrasonography (TCD). All patients were operated on within 72 hours after SAH. Patients who presented with remarkable brain oedema or with pathological intracranial pressure (ICP) due to mass effects of a haematoma, and who were in a poor neurological condition classified according to Hunt-Hess as grade V were excluded from this study. Serial TCD examination of the middle cerebral arteries (MCA) and anterior cerebral arteries (ACA) started within 48 hours after SAH and were performed daily up to three weeks. A statistically significant correlation between blood load designated according to Fisher's grading as group CT I-CT IV and mean flow velocities (MFV) was found in groups CT I, II, and III. High values of MFV in MCA examinations were noted in patients with severe SAH (group CT III)--161 cm/s, and low values in patients without SAH (group CT I)--119 cm/s. Patients with haematocephalus and/or haematoma without a mass effect (group CT IV) had lower blood flow velocities than patients with severe SAH (group CT III) but values were higher than in patients without SAH (group CT I). The number of days for which MFV in the MCA was > 120 cm/s and was statistically (p < 0.05) correlated with the amount of blood clots as observed in the respective CT (in group CT I, II, and III). MFV values in the anterior cerebral artery (ACA) were lower than those obtained in the middle cerebral artery (MCA) in all groups. Statistically significant (p < 0.05) differences were noted between groups CT I and CT III (first and third week) and between groups CT I and CT IV (third week). If the SAH was extensive in the CT scan, pathological values of MFV > 90 cm/s were observed in ACA, and this was more pronounced in group CT III than in group CT IV. Blood flow velocities obtained via TCD were registered to compare side-to-side differences and particularly high differences were observed in patients with severe SAH. It is concluded that the amount of blood clots in the initial computed tomography after SAH is significantly correlated with cerebral blood flow velocity measurements by TCD.  相似文献   
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