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991.
Paramyxovirus-like inclusions in two cases of pycnodysostosis 总被引:1,自引:0,他引:1
We describe the biochemical and histological features of two related patients with pycnodysostosis. Examination of bone biopsies taken from both patients showed the presence of large nonfunctional osteoclasts which contained paramyxovirus-like inclusions similar in size and arrangement to those found in Paget's disease of bone. No radiographic, histologic or biochemical evidence for Paget's disease was found in either patient. The presence of osteoclast inclusions may not be specific for Paget's disease, therefore, and could be the result rather than the cause of abnormal osteoclast metabolism. 相似文献
992.
Jonas T. Johnson David G. Mayernik Eugene N. Myers Teresa A. Nolan Victor L. Schramm Barbara S. Sigler Robin L. Wagner 《Head & neck》1987,9(6):336-340
Patients with locally advanced, inoperable squamous cell carcinoma of the head and neck were offered three courses of cisplatin and 96-h 5-fluorouracil (5-FU) infusion. Subsequent therapy included surgery when feasible, irradiation therapy, and a maintenance program of methotrexate (MTX)-5-FU. Thirty-three patients were evaluated prospectively. Seven patients underwent a single course of chemotherapy. Five patients underwent two courses of chemotherapy. Twenty-one patients underwent three courses of adjuvant chemotherapy. The overall response rate was 48% (16 of 33). Fifteen of 21 patients (76%) receiving three courses of chemotherapy evidenced a response; this included three complete responses (CRs) (9%). No responses were seen in patients receiving only one or two courses of chemotherapy. Among responding patients, the initial favorable response to chemotherapy was apparent after the first course of chemotherapy. Patients who failed to demonstrate any response after two courses of chemotherapy did not respond after a third course. A significant group of patients fail to respond and should be offered participation in other investigational protocols as they become available. 相似文献
993.
Anticholinergic sensitivity in patients with dementia of the Alzheimer type and age-matched controls. A dose-response study 总被引:1,自引:0,他引:1
T Sunderland P N Tariot R M Cohen H Weingartner E A Mueller D L Murphy 《Archives of general psychiatry》1987,44(5):418-426
We compared the cognitive and behavioral responses to three intravenous doses of scopolamine (0.1, 0.25, and 0.5 mg) and placebo of ten patients with dementia of the Alzheimer type (DAT) and ten age- and sex-matched elderly control subjects. The patients with DAT showed significant behavioral and cognitive but not physiologic changes at a lower scopolamine dose (0.25 mg) than did the normal elderly controls. Cognitive tests of new learning and semantic knowledge revealed significant impairments at the 0.25-mg scopolamine dose in the patients with DAT, while the responses of the control population were essentially unchanged. Behaviorally, mild euphoria, motor incoordination, and hostility occurred in the patients with DAT but not the controls at the 0.25-mg dose. These differences were unrelated to peripheral physiologic changes produced by the different scopolamine doses. These results indicate that central nervous system functions such as cognition and certain elements of behavior are more sensitive to temporary cholinergic blockade in patients with DAT than in normal age-matched controls. We review implications concerning the status of central cholinergic function in patients with DAT in light of neuropathologically demonstrated cholinergic system lesions in DAT. 相似文献
994.
995.
Sera from 200 babies and young children and from 205 mother-newborn pairs were tested for haemagglutination inhibiting antibody against three A-H1N1, one A-H2N2, four A-H3N2, and two influenza B viruses. The results indicated that a higher concentration of antibody against all influenza A and B viruses tested was found more frequently in maternal sera than in neonatal sera. High prevalences of antibody and high geometric mean titres against the A-H2N2-1957 and A-H3N2-1968 viruses from the eras 1957-1968 and 1968-now, respectively, were found in the age groups above 15 years. The antibodies against former and recent epidemic influenza viruses of the A-H3N2 subtype, found among different adult age groups in Mwanza, Tanzania, showed a pattern similar to that in the population of The Netherlands. 相似文献
996.
997.
G H Collins N R West J D Parmely F M Samson D A Ward 《Journal of neuropathology and experimental neurology》1986,45(6):721-741
In an effort to develop a method of tissue injury which would provide a model for the study of axonal regrowth in adult mammalian central nervous system (CNS), we have analyzed the effects of freezing in the dorsal columns of more than 200 rat spinal cords. The effects of temperature and time of exposure upon the size, shape, distribution and histologic characteristics of the lesion have been assessed during the first seven days following the injury. The upper threshold for injury occurs at -3 degrees C for 15 minutes. Between -3 degrees C and -12 degrees C the tissue changes vary in extent and characteristics. Selective damage to axons and myelin occurs with sparing of the supportive cells followed by proliferation of a cellular matrix. At seven days, the lesions produced by -8 degrees C for 15 to 60 minutes have neither axons nor myelin sheaths and consist of a dense cellular matrix of macrophages and presumed glial cells. With these tissue characteristics, and the preservation of tissue continuity without obstructive barriers, this model would appear to be potentially suitable for the study of axonal regrowth potential in mammalian CNS. 相似文献
998.
N R Ghatak W W Campbell R H Lippman M G Hadfield 《Journal of neuropathology and experimental neurology》1986,45(4):385-395
Morphologic study of the spinal cord of a patient with generalized motor deficits revealed changes in the anterior horns characterized by the selective loss of large motor neurons, gliosis and the abnormal accumulation of 10 nm filaments which appeared as argyrophilic spheroids in the perikarya and axons of motor neurons. The ventral roots were predominantly affected and showed a variable loss of axons. The remaining axons displayed prominent onion-bulb formations, frequent axonal sprouting and occasionally evidence of active demyelination. The coexistence of a demyelinating motor radiculopathy and anterior horn changes simulating those of amyotrophic lateral sclerosis (ALS) may contribute to our understanding of the unresolved question of whether the neuronal perikaryon or its axon is the primary target in the pathogenesis of ALS. These observations also indicate that a rigid separation of pathogenetic mechanisms into neuronopathy, axonopathy and myelinopathy may not be always possible. 相似文献
999.
We conducted a clinical and pathologic review of 14 patients with immature ovarian teratoma. In this series of patients, one had monodermal malignant neuroectodermal teratoma and two others had immature ovarian teratoma in association with immature presacral teratoma. Because of the small number of cases of immature ovarian teratoma and the diverse therapeutic modalities used in this study, we cannot recommend a specific treatment for patients with this tumor on the basis of our findings. The histologic grade of the tumor seemed to be a reliable indicator of prognosis. Grade 0 metastatic lesions should be considered benign and are associated with a favorable prognosis. 相似文献
1000.
L. C. Scott G. K. Wright G. S. Rai A. N. Exton-Smith J. M. Gardiner 《International journal of geriatric psychiatry》1991,6(8):583-588
Memory performance of elderly patients in the early stages of Alzheimer's disease (DAT) was compared with that of elderly control subjects. In explicit tests of recognition memory, which involve conscious recollection, the DAT patients were grossly impaired. In implicit tests of anagram solution and wordstem completion, which do not require conscious recollection, the DAT patients were not impaired. These findings further support the idea that a separate memory system, episodic memory, underlies conscious recollection, that it is this system which is most commonly damaged in amnesia, and that memory systems not involving conscious recollection may be spared in the early stages of Alzheimer's disease. 相似文献