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131.
A total of 68 major complications of cervical myelography were reported by 220 neuroradiologists in a mail survey. Two-thirds of the complications were attributed to cervical spine hyperextension and one-third to lateral C1-2 puncture. Narrow sagittal diameter of the spinal canal and severe cervical spondylosis were frequent contributing factors to hyperextension injury of the cervical spinal cord. Clinical and radiographic premyelography screening is suggested, with magnetic resonance imaging performed first in patients with spinal canal stenosis, severe spondylosis, and/or myelopathy of any cause. Neck extension should be minimal during myelography. All C1-2 punctures should be monitored with lateral fluoroscopy for accurate needle positioning and prevention of contrast medium injection into the spinal cord. 相似文献
132.
133.
Presenile dementia in Israel 总被引:1,自引:0,他引:1
T Treves A D Korczyn N Zilber E Kahana Y Leibowitz M Alter B S Schoenberg 《Archives of neurology》1986,43(1):26-29
A nationwide epidemiologic study of presenile dementia of the Alzheimer type (PDAT) with onset through age 60 years was carried out in Israel. The Israeli National Neurologic Disease Register and clinical records of all patients discharged from hospitals between 1974 and 1983 with a neurologic or psychiatric diagnosis suggestive of dementia were reviewed. A total of 71 Jewish patients with onset of PDAT between 1974 and 1978 was ascertained. The age at onset in these patients ranged from 43 to 60 years. The median survival was 8.1 years, with slightly longer survival if onset occurred before age 55 years, even after correction for expected mortality according to age and sex. The average annual incidence rate per 100,000 population at risk was 2.4 in the population aged 40 through 60 years. Although the incidence rates were slightly greater for women, the difference between the rates by sex was not statistically significant. The age- and sex-adjusted incidence of PDAT per 100,000 population was significantly higher in those born in Europe or America (2.9) than in those born in Africa or Asia (1.4). No significant difference in survival was found between these two groups. The curve of the incidence rates by age for PDAT in Israel is continuous with that for senile dementia of the Alzheimer type collected by similar methods elsewhere, which suggests that one disease process may account for both conditions. 相似文献
134.
RS de Vreeze D de Jong IH Tielen HJ Ruijter PM Nederlof RL Haas F van Coevorden 《Modern pathology》2009,22(2):223-231
Almost all primary retroperitoneal liposarcomas can be classified as well-/dedifferentiated liposarcoma. Rarely, however, primary retroperitoneal liposarcoma is classified as myxoid/round cell liposarcoma, based on the presence of myxoid areas and vascular crow's feet pattern, which has resulted in a debate on the classification of liposarcoma in the retroperitoneum. Genetically, myxoid/round cell liposarcoma and well-/dedifferentiated liposarcoma are different diseases. Myxoid/round cell liposarcoma is characterized by a translocation causing FUS-CHOP or EWSR1-CHOP fusion, whereas well-/dedifferentiated liposarcoma is characterized by an amplification of the 12q13-15 region, including MDM2 and CDK4 genes. As myxoid/round cell liposarcoma is highly radio- and chemosensitive, differentiation between subtypes is important to optimize treatment. We studied whether primary retroperitoneal liposarcomas diagnosed as myxoid/round cell liposarcoma represent molecularly true myxoid/round cell liposarcoma or are histopathological mimics and represent well-/dedifferentiated liposarcoma. Primary retroperitoneal myxoid/round cell liposarcoma (n=16) were compared to primary extremity myxoid/round cell liposarcoma (n=20). Histopathological and immunohistochemical features were studied. Amplification status of the 12q13-15 region was studied using a multiplex ligation-dependent probe amplification analysis, and FUS-CHOP or EWS-CHOP translocations were studied using RT-PCR. In primary retroperitoneal myxoid/round cell liposarcoma, MDM2 and CDK4 staining was both positive in 12 of 15 cases. In primary extremity myxoid/round cell liposarcoma, MDM2 was negative in 18/20 and CDK4 was negative in all cases. Multiplex ligation-dependent probe amplification showed the amplification of 12q13-15 region in 16/16 primary retroperitoneal myxoid/round cell liposarcomas and in 1/20 primary extremity myxoid/round cell liposarcomas. Translocation was present in all (18/18) primary extremity myxoid/round cell liposarcomas, but absent in all primary retroperitoneal myxoid/round cell liposarcomas. On the basis of immunohistochemical and molecular characteristics, apparent primary retroperitoneal myxoid/round cell liposarcoma can be recognized as well-/dedifferentiated liposarcoma with morphological features mimicking myxoid/round cell liposarcoma. In these cases, treatment should probably be specifically designed as for well-/dedifferentiated liposarcoma. Moreover, finding of myxoid/round cell liposarcoma translocations in a retroperitoneal localization is highly suggestive of metastasis and should prompt search for a primary localization outside the retroperitoneum. 相似文献
135.
136.
Antibody-dependent enhancement of human immunodeficiency virus type 1 (HIV-1) infection in vitro by serum from HIV-1-infected and passively immunized chimpanzees. 总被引:17,自引:4,他引:13 下载免费PDF全文
W E Robinson Jr D C Montefiori W M Mitchell A M Prince H J Alter G R Dreesman J W Eichberg 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(12):4710-4714
Based on recent reports of antibody-dependent enhancement of human immunodeficiency virus type 1 (HIV-1) infection in vitro by serum from HIV-1-infected humans, sera from HIV-1 antibody-positive chimpanzees (Pan troglodytes) was evaluated for enhancing activity in an in vitro infection assay that uses MT-2 cells (a human lymphoblastoid cell line). Although fresh chimpanzee serum was found to have pronounced infection-enhancing properties in the absence of antibody to HIV-1, this effect was abolished by heat inactivation (57 degrees C, 1 hr) or treatment with cobra venom anticomplementary protein. Heat-inactivated, HIV-1 antibody-positive chimpanzee serum could enhance HIV-1 infection of MT-2 cells in vitro when combined with fresh, normal human serum. By serial serum samples from three HIV-1-infected chimpanzees, HIV-1 antibody-positive chimpanzees are shown to develop enhancing antibodies early in infection (2 mo postchallenge), whereas neutralizing antibodies develop later. Over the course of HIV-1 infection, this enhancing activity decreases while neutralizing activity increases, suggesting a possible role for enhancing and neutralizing activities in HIV-1 pathogenesis. The enhancing activity of an IgG fraction used to passively immunize chimpanzees against HIV-1 infection is shown to be present at dilutions as high as 1:65,000, offering an interesting possible reason for the failure of passive immunization to protect chimpanzees from HIV infection. These results suggest that serum from HIV-1-immunized chimpanzees might be tested to determine whether current HIV-1 candidate vaccines induce production of antibodies that mediate antibody-dependent enhancement of HIV-1 infection in this in vitro assay. 相似文献
137.
目的:探讨谷氨酸对脑组织即早基因表达的影响以及醋酸锌对谷氨酸诱导c-fos和c-jun过度表达的拮抗作用。方法:体外小鼠海马脑片培养;在培养基中加入200μmol/L的谷氨酸(或同时加入谷氨酸和醋酸锌),作用0.5,1,2,3h,然后进行RT-PCR实验,检测c-fos和c-jun的表达变化。结果:200μmol/L谷氨酸处理的脑片中,1-2h期间c-fos的表达升高,当谷氨酸与100μmol/L醋酸锌共同处理脑片时,1-3h期间c-fos表达基本恢复正常;200μmol/L谷氨酸作用下,脑片c-jun表达水平从0.5h起即明显升高,谷氨酸与醋酸锌共同作用时,可见c-jun基因在各检测时段表达基本接近正常。结论:谷氨酸可引起c-fos及c-jun的过度表达,锌离子可拮抗谷氨酸诱导的c-fos和c-jun过度表达作用,使二基因表达恢复正常。 相似文献
138.
Hintergrund: Die infektiöse Endokarditis hat eine hohe Morbidität und Letalität. Daher erfolgt die Antibiotikatherapie stets intravenös und über mehrere Wochen. Patientenauswahl für ambulante Behandlung: Für eine ambulante antibiotische Therapie sind nur ausgewählte Patienten geeignet, bei denen eine kontinuierliche intravenöse Gabe auch an den Wochenenden gewährleistet ist. Generell sollten außerdem nur hämodynamisch stabile und ansonsten komplikationsfreie Patienten, bei denen der auslösende Erreger nachgewiesen wurde, ambulant behandelt werden. Durchführung: Unter pharmakologischen Gesichtspunkten sollte über die gesamte Therapiedauer eine intravenöse oder intramuskuläre Gabe der Antibiotika erfolgen. So kann eine Endokarditis, verursacht durch penicillinsensible Streptokokken, der größten Gruppe unter den Endokarditiserregern, mit einer einmal täglichen Gabe von Ceftriaxon parenteral über 4 Wochen auch ambulant suffizient behandelt werden. Für alle anderen Erreger liegen noch keine ausreichenden Daten bezüglich einer ambulanten Therapie vor. Die meist komplexeren Antibiotikaregime für diese Erreger sind für den ambulanten Gebrauch wenig praktikabel. Computergesteuerte Pumpen können diese Nachteile in Zukunft möglicherweise überwinden. Grenzen: Jede geplante ambulante Therapie sollte in den ersten Tagen unter stationären Bedingungen eingeleitet und erst nach Ansprechen der Therapie ambulant fortgesetzt werden. Zur Zeit lässt die ambulante Infrastruktur eine verlässliche, ambulante Therapie und Verlaufskontrolle an 7 Tagen in der Woche problematisch erscheinen. Dennoch bietet die ambulante Antibiotikatherapie gegenüber der stationären bezüglich des Kosten-Nutzen-Effekts zukünftig eine interessante Alternative. Background: Infective endocarditis has a high morbidity and letality. Therefore antibiotic treatment has to be intravenous to achieve high blood levels and has to last several weeks without an interruption of treatment at the weekends. Patient Selection for Outpatient Therapy: It is therefore crucial to select the patient group that is suited for an outpatient, antibiotic therapy very carefully. In general only hemodynamically stable patients without complications in whom the responsible organism has been identified should be considered. Treatment: From a pharmacological point of view intravenous or intramuscular application for the complete duration of therapy is obligatory. Endocarditis caused by penicillin-susceptible streptococci, the biggest group of organisms responsible for endocarditis, can be treated with Ceftriaxon once daily for 4 weeks. For other organisms there are at present no data available which support the feasibility of an outpatient therapy. In particular antibiotic therapy with a complex regimen for those organisms is not practicable for outpatient usage. Possibly, in the near future computer controlled pumps might overcome this disadvantage. Limits: Every outpatient therapy should be initiated under inpatient conditions and only after an initial response to the antibiotic therapy continued in an outpatient setting. Today reliable outpatient therapy and follow-up 7 days a week under the given outpatient infrastructur is problematic and remains an exception. However, considering cost-effectiveness outpatient as compared to inpatient antibiotic therapy could be an interesting economically advantageous alternative. 相似文献
139.
P Alter E M Walthers J R Schaefer B Maisch 《VASA. Zeitschrift für Gef?sskrankheiten》2001,30(4):299-302
We report on a high vena cava inferior interruption immediately at the insertion to the right atrium in a patient with Hirschsprung disease assessed by angiography, CT, and MRI. Hirschsprung disease is frequently associated with Down, Undine, Waardenburg, Bardet-Biedl, Smith-Lemli-Opitz and Goldberg-Sphrintzen syndromes. We suggest that the association of these two malformations are most likely interrelated and should be considered as a new syndrome. 相似文献
140.
Ultraviolet irradiation of blood prevents transfusion-induced sensitization and marrow graft rejection in dogs 总被引:1,自引:1,他引:0
In a canine model using DLA-identical littermate pairs, we have shown that a regimen of three transfusions of donor blood given 24, 17, and 10 days before transplant uniformly leads to marrow graft rejection, presumably due to sensitization to minor (non-DLA) histocompatibility antigens. Untransfused dogs uniformly achieve sustained engraftment. In the present study, we investigated whether the exposure of blood to ultraviolet (UV) light (220-300 nm) prior to transfusion prevented sensitization of the recipient and allowed for successful marrow engraftment. Ten dogs were each given three pretransplant transfusions from the marrow donor. Each transfusion consisted of 50 mL of whole blood exposed in vitro to UV light for a total of 1.35 J/cm2. All ten dogs achieved engraftment. In contrast, all four dogs that had received sham-exposed transfusions rejected their grafts. In vitro studies revealed that although cell viability was not affected, leukocytes contained in UV-exposed blood were unable to function as stimulator cells in mixed leukocyte cultures or as accessory cells in mitogen- stimulated cultures. These data are consistent with the hypothesis that accessory cells are involved in transfusion-induced sensitization. We conclude that in vitro exposure of blood to UV light before transfusion prevents sensitization and allows for subsequent marrow engraftment. 相似文献