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961.
962.
Experience with electrical diagnostic and high-potential tests, performed at the terminals of unshielded cables in older nuclear and thermal plants is presented. The three basic types of cable-low- and high-voltage power cables, control cables and instrumentation cables-that are important to the reliable operation of a generating station and large industrial plants are described, and their aging mechanisms are indicated. Dielectric testing of unshielded cables, the effect of grounding, field testing of station cables, and insulation characterization at low frequencies are discussed  相似文献   
963.
The object-oriented approach to integrating knowledge data, and models is examined. Under the object-oriented paradigm, everything is an object, which is itself an encapsulation of data and methods to manipulate and access the data within the object. Thus knowledge, data, and models can be defined as special kinds of objects. Active knowledge/data language (KDL), a functional object-oriented database system is considered, covering the active-KDL-type system and functions, and query-driven simulation  相似文献   
964.
The design and application of an apparatus for measuring pain threshold by controlling the conditions of an experiment carefully and measuring stimulus and response parameters precisely are described. Heat generated by an incandescent source, focused on a small area of the subject's forehead, was used as the stimulus to determine the cutaneous pain threshold. The equipment was in different experiments in which the threshold of thermocutaneous pain was evaluated with and without the use of an analgesic. The analgesic Pirazolane was found to reduce thermocutaneous pain threshold and to diminish the average duration of alpha rhythm blockade and the response of galvanic skin resistance. The results of these experiments with constituents of marijuana indicated that canabidiol provokes and increases the sensibility of pain reactions while both Δ9 THC and canabinol do not modify the pain threshold  相似文献   
965.
While information systems continue to be promoted within organizations as tools to support strategic decision-making, there is growing concern over the ability of such systems to model the social and political complexity of the situations to which they are being applied. This paper examines the nature of organizational decision-making and the use of computer-based systems to support this activity. The debate queries the extent to which such artifacts should be allowed to become enmeshed and embedded within the strategic decision-making activities of organizations which operate within increasingly complex environments.  相似文献   
966.
967.
A 59-year-old female patient with atypical chronic herpes simplex encephalitis was reported. Initial symptom was persistent myoclonus involving the trunk and limb muscles, and later lateral gaze palsy to the left side, cerebellar ataxia, consciousness disturbance and other brainstem symptoms including absence of corneal and gag reflex and vocal cord palsy developed. The patient was successfully treated with high dose of acyclovir. Electroencephalogram was normal in the initial stage but later showed diffuse slow waves. Although CT scan and MRI showed no abnormal finding in the cerebral cortex, brainstem lesion was observed on PD weighted image of MRI. Lumbar puncture yielded a clear cerebrospinal fluid, with slightly elevated protein, increased lymphocytes, and elevated titer of herpes simplex virus type I. The serological data, albumin ratio (10.3), antibody index (12.3) and antibody ratio (7.1) were consistent with herpes simplex encephalitis. Ten days' administration of acyclovir, 1,200 mg a day and repeated three times, was prominently effective for the myoclonus and consciousness disturbance. A diagnosis of chronic herpes simplex encephalitis initially presenting with brainstem encephalitis was made. Judging from the clinical and EEG findings, the brainstem lesion was initially thought to be a cause of myoclonus in this case. However, somatosensory evoked potential (SPE) of both upper and lower extremities revealed enlarged amplitude (giant SEP), and long loop reflex was enhanced (C-reflex) on the left. Giant SEP and C-reflex imply cerebral cortex as the origin of the myoclonus. Brainstem inflammatory lesion might have involved the ascending inhibitory system, thus disinhibiting the cortical sensorimotor area and causing cortical myoclonus.  相似文献   
968.
In a prospective study of layered versus mass closure of abdominal incisions in infants and children, 34 cases underwent wound closure by layered and mass closure technique on an alternate basis. All the patients were assessed for their nutritional status and haemoglobin level pre-operatively, and wound complications were compared with respect to closure technique, nutritional status and normal haemoglobin level. Presence of protein energy malnutrition and anaemia did not increase the risk of wound complications with either of the technique.  相似文献   
969.
Cellular and molecular mechanisms involved in the deposition of extracellular matrix components in both normal and fibrotic liver are still poorly understood. We have investigated the influence of cooperation between Ito cells and hepatocytes in matrix deposition in vitro. Immunoprecipitation of radiolabeled proteins from media of 5-day-old Ito cell primary cultures showed that these cells secreted high levels of the major basement membrane components, ie, collagen IV, laminin, and entactin/nidogen. By immunocytochemistry, precursors of basement membrane components were found intracellularly, but only scarce deposits were seen around the cells. When hepatocytes were added to 2-day-old Ito cell primary cultures, they established close contacts with Ito cells in less than 24 hours and expressed ZO-1, a tight junction-associated protein not detectable in standard hepatocyte culture. Cytochemistry analysis revealed an abundant extracellular matrix deposited over hepatocyte cords and between hepatocytes and Ito cells. Immunocytochemistry studies showed that this matrix contained laminin, fibronectin, and collagens proIII and IV. These data indicate that a high level of matrix protein synthesis by liver cells in vitro is not sufficient to induce extracellular matrix deposition, and that cell-cell interactions are strongly involved in this process. Hepatocyte/Ito cell co-culture, which may reflect the actual situation in vivo, represents a useful tool for studying liver fibrogenesis.  相似文献   
970.
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