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991.
We describe a myelolipoma of the thoracic spine in a patient with gradual and progressive myelopathy. MR imaging showed this predominately fatty lesion to be extradural in location.  相似文献   
992.
Summary.  Clones of an African cassava mosaic virus isolate originating from Nigeria (ACMV-NOg) were shown to be infectious to cassava by biolistic inoculation. The production of pseudorecombinants between ACMV-NOg and clones of an ACMV isolate originating from Kenya (ACMV-K) indicated that the lack of infectivity of ACMV-K to cassava was due to defect(s) in the DNA B genomic component; this component encodes two proteins involved in cell-to-cell movement. This is the first demonstration of infectivity of a cloned geminivirus to cassava and conclusively proves that ACMV is the causative agent of cassava mosaic disease. The potential uses of infectious ACMV clones and the means by which to introduce them into cassava are discussed. Received January 18, 1998 Accepted May 27, 1998  相似文献   
993.
994.
Sexually dimorphic growth hormone (GH) secretory pattern is important in the determination of gender-specific patterns of growth and metabolism in rats. Whether GH secretion in humans is also sexually dimorphic and the neuroendocrine mechanisms governing this potential difference are not fully established. We have compared pulsatile GH secretion profiles in young men and women in the baseline state and during a continuous intravenous infusion of recombinant human insulin-like growth factor I (rhIGF-I). During the baseline study, men had large nocturnal GH pulses and relatively small pulses during the rest of the day. In contrast, women had more continuous GH secretion and more frequent GH pulses that were of more uniform size. The infusion of rhIGF-I (10 microg/kg/h) potently suppressed both spontaneous and growth hormone-releasing hormone (GHRH)-induced GH secretion in men. In women, however, rhIGF-I had less effect on pulsatile GH secretion and did not suppress the GH response to GHRH. These data demonstrate the existence of sexual dimorphism in the regulatory mechanisms involved in GH secretion in humans. The persistence of GH responses to GHRH in women suggests that negative feedback by IGF-I might be expressed, in part, through suppression of hypothalamic GHRH.  相似文献   
995.
996.
A novel cardiokymograph system is introduced. The new system features a capacitance transducer with increased sensitivity and can be used in multichannel measurements. The novelty of this technique is the injection of a current into the patient coupled with the use of a capacitive displacement transducer and the possibility of multichannel monitoring. It provides for the possibility of removing breath noise when some signal processing technique, such as adaptive filtering, is used. Further investigation is needed to demonstrate clinical significance and pathologies.  相似文献   
997.
Rheo-optical Fourier transform infrared spectroscopy was used to analyze the orientational behavior of hard and soft segments of thermoplastic poly(ether urethane)s (TPU-Et) and poly(ester urethane)s (TPU-Es) and their blends with a 20 mass-% contribution of either polyethylene (PE) or polypropylene with an amorphous rubber phase (PP). The blends show a reduced stress level, lower elongation-to-break and a lower degree of orientation of the segments — especially for the TPU-Es blends — compared to those of pure TPU's when uniaxially elongated. Blends of TPU-Et with PP show reduced stress but increased strain compared to pure films of TPU-Et. This is caused by an improved adhesion of the rubber phase in the polypropylene and the polyether phase of TPU-Et. Optical micrographs visualize deformed polyolefin particles in elongated films of TPU-Et/PP blends. In the TPU-Et/PP blend we could achieve equivalent orientation for the polyolefin phase and the segments of TPU-Et caused by this higher phase adhesion compared to the other blends. Orientation functions (OF's) of absorption bands which specifically represent hard or soft polyurethane segments or which are characteristic of the polyolefin phase have been calculated to monitor the molecular alignment due to the mechanical treatment.  相似文献   
998.
999.
纤维支气管镜胸膜腔检查对原因不明胸腔积液的诊断价值   总被引:2,自引:0,他引:2  
为评价纤维支所管镜行胸膜检查在诊断原因不明胸腔积液中的价值,用纤维支气管镜对10例原因不明的胸腔积液患者进行胸腔检查。结果9例2检查后明确了病因,且无并发症,提示该法对于不明胸腔积液的诊断是一种阳性率高、安全、简便的检查方法。  相似文献   
1000.
Aims: Extra-adrenal paragliomas are neoplasms which have been the subject of much debate regarding parameters to establish their biological behaviour. This study describes the clinicopathological and immunohistochemical features of 30 cases of spinal paragliomas. Methods and results: There were 15 male and 15 female patients. The median age at diagnosis was 46 years (range 20–74 years). Fourteen patients presented with back pain, two with numbness of the lower extremities, one with difficulty in walking and one with spinal cord compression. Nineteen tumours were located in the lumbar region, six in the cauda equina, two in the filum terminale, two in the thoracic region and one in the cervical region. All patients underwent gross total excision. The size of the tumours ranged from 10 to 50 mm. Histologically, 18 neoplasms showed alveolar (Zellballen) pattern, seven a spindle component, two eosinophilic granular cells suggestive of oncocytic metaplasia, two melanin pigment and one ganglion cells. Positive immunohistochemical results include: neuron-specific enolase 23/23 (100%), synaptophysin 21/23 (91%), S100 protein 22/23 (95%, sustentacular cells), leu-enkephalin 11/23 (47%), somatostatin 8/23 (34%), focal glial fibrillary acidic protein 7/23 (30%), focal keratin 5/23 (21%), neurofilament proteins 3/23 (13%) and adrenocorticotrophic hormine (ACTH) 1/23 (4%). Follow-up information obtained in 20 patients show 17 patients alive over a period of 6–216 months. One patient had bone metastases. Two patients died of unrelated causes, including one of congestive heart failure and one of myocardial infarction. Conclusions: In our experience, spinal paragangliomas behave as slow-growing tumours susceptible to potential cure by total excision. We agree with the current World Health Organization (WHO) classification as grade I tumours. Less than 1% may be locally aggressive. Spinal paragangliomas immunoreact not only for conventional neuroendocrine markers but also for peptides including somatostatin and ACTH and focally for the epithelial marker keratin.  相似文献   
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