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61.
W.HJ 《军民两用技术与产品》2014,(8):35-35
机械科学研究总院北京机电研究所承担“2000KN立式冷摆动辗压机开发研究”项目通过验收,研发的2000kN矿式冷摆动辗压机具有自主知识产权,填补了国内空白,达到国际先进水平,人选“2013度中关村科技园区首台(套)重大技术装备试验、示范项目。 相似文献
62.
W.HJ 《军民两用技术与产品》2014,(8)
正中国科学院合肥物质科学研究院安徽光学精密机械研究所成功研制出1种用于机载、可快速获取区域环境大气污染成分的环境大气成分探测系统,并通过了安徽省科技成果转化服务中心组织的科技成果鉴定。该机载环境大气成分探测系统由大气环境激光雷达、差分吸收光谱仪和多角度偏振辐射计及主控管理器等4个子系统组成。研究人员研制出了国内首台探测气溶胶和云的双波长偏振航空遥感激光雷达。 相似文献
63.
OBJECTIVE: Occupational skin changes in hairdressers are very common. Morbidity, however, has not yet been quantified precisely. METHODS: A cohort of 2,352 hairdressing apprentices (of the 2,570 invited to participate, i.e., 91.5% response) was prospectively followed for the duration of their vocational training (3 years) by three examinations. Three waves (years) were recruited in 1992, 1993, and 1994 from 15 vocational training schools in northwestern Germany. RESULTS: The point prevalence of (mostly slight) irritant skin changes of the hands increased from 35.4% in the initial examination to 47.5% in the intermediate examination and to 55.1% in the final examination. Given a more conservative definition of a case of "hand dermatitis," these estimates were 12.9%, 23.5%, and 23.9%, respectively. Altogether, 34.3 and 15.2 cases of "skin changes (any degree)" and "hand dermatitis," respectively, in 100 person-years were observed during the study period. The incidence rate, i.e., the number of newly diseased study participants in relation to the person-time at risk contributed, decreased in the course of the study. The proportion of dropouts until final follow-up was 51.8%. CONCLUSION: The present results appear to lie in a range with those found in other, much smaller cohort studies. However, comparison of the results is hampered either by the lack of a clear definition or by a different definition of "person-time at risk" or "a case of hand dermatitis." As compared with an external control group of office apprentices, the incidence was several times higher in hairdressing apprentices, which points to the high risk for skin damage in this occupation. 相似文献
64.
C van Campen HJ Sixma JJ Kerssens L Peters JJ Rasker 《Canadian Metallurgical Quarterly》1998,37(4):362-368
BACKGROUND: Stress can exacerbate a number of psychiatric disorders, many of which are associated with prefrontal cortical (PFC) cognitive deficits. Biochemical studies demonstrate that mild stress preferentially increases dopamine turnover in the PFC. Our study examined the effects of acute, mild stress exposure on higher cognitive function in monkeys and the role of dopaminergic mechanisms in the stress response. METHODS: The effects of loud (105-dB) noise stress were examined on a spatial working memory task (delayed response) dependent on the PFC, and on a reference memory task with similar motor and motivational demands (visual pattern discrimination) dependent on the inferior temporal cortex. The role of dopamine mechanisms was tested by challenging the stress response with agents that decrease dopamine receptor stimulation. RESULTS: Exposure to noise stress significantly impaired delayed-response performance. Stress did not impair performance on "0-second" delay control trials and did not alter visual pattern discrimination performance, which is consistent with impaired PFC cognitive function rather than nonspecific changes in performance. Stress-induced deficits in delayed-response performance were ameliorated by pretreatment with drugs that block dopamine receptors (haloperidol, SCH 23390) or reduce stress-induced PFC dopamine turnover in rodents (clonidine, naloxone hydrochloride). CONCLUSIONS: These results indicate that stress impairs PFC cognitive function through a hyperdopaminergic mechanism. Stress may take the PFC "off-line" to allow more habitual responses mediated by posterior cortical and subcortical structures to regulate behavior. This mechanism may have survival value, but may often be maladaptive in human society, contributing to the vulnerability of the PFC in many neuropsychiatric disorders. 相似文献
65.
Determination of Functional Residual Capacity (FRC) can be performed through washout methods, indicator gas dilution or bodyplethysmography. Some of these techniques have been adapted for use in intensive care patients whilst being mechanically ventilated. However, most measurement setups are bulky, cumbersome to use and their running costs are high. Hence FRC measurement has not become a routine method in intensive care although it offers considerable advantages in the management of ventilated patients such as the determination of "best PEEP", the detection of progressive alveolar collapse in the course of acute lung injury and during weaning from mechanical ventilation. Up to now most efforts to improve and simplify FRC measurement were made at the expense of accuracy. An ideal method ought to be accurate, easy to handle and cost-effective. It should supply not only FRC data but also information about intrapulmonary gas distribution and dead space. These demands can be met using modern data acquisition software. The pros and cons of all methods available for FRC measurement are discussed in view of their suitability for intensive care patients. A conventional nitrogen washout using emission spectroscopy for measurement of nitrogen concentration gives satisfying exact values for the determination of the parameters mentioned above. The measurement error can be lowered under 5% by special corrections for flow and nitrogen signal (delay and rise times, changes of gas viscosity). For flow measurement a normal pneumotachograph can be used. Using a laptop computer for data acquisition the bed-side monitor fulfills most of the demands in intensive care. It is then also possible to measure indices of intrapulmonary gas distribution such as Alveolar Mixing Efficiency and Lung Clearance Index. 相似文献
66.
Fibromuscular dysplasia (FMD) is one of the most important mimics of vasculitis. FMD is more prevalent in women and may cause infarcts of organ systems including the brain, intestines, and extremities. These acute clinical presentations often raise the suspicion of vasculitis and therefore rheumatologists will be asked to evaluate these patients. One of the frequent manifestations of FMD is renal artery involvement. Angiographic evaluation often shows a "string of beads" appearance of the renal arteries but sometimes only tapering of the vascular lumen or cutoffs may be seen. In contrast, hepatic artery involvement with FMD occurs much less frequently and may initially present with life threatening intraabdominal bleeding. Celiac angiograms of these patients often show aneurysms, a presentation similar to vasculitis. Only a high level of suspicion for FMD and careful evaluation of clinical facts will lead to correct diagnosis. This will prevent the wrong diagnosis of vasculitis and subsequent treatment with potentially toxic medications. We present 2 cases of FMD involving the renal and hepatic arteries that illustrate this diagnostic challenge. 相似文献
67.
HJ Hachen 《Canadian Metallurgical Quarterly》1993,123(11):443-448
A quarter of a century ago, in October 1964, the first spinal cord injury center in Switzerland was opened at Geneva University Hospital. At that time all para- and tetraplegics were classified as "high-risk" patients. Early mortality, covering the initial four weeks following trauma, was still around 15%. The available resources for diagnostic assessment were limited to clinical examination and neuroradiological assessment (subsequently improved by the introduction of tomography and gas myelography). A great many patients suffered a deteriorated neurological level due to inadequate, multiple transfers between hospitals. Most patients who are paralyzed following a road-traffic accident show severe polytrauma. Their chances of survival and functional recovery have greatly improved in recent years due to efficient emergency transport by helicopter, admission to an intensive care unit (respiratory therapy, prophylactic anticoagulation, gastrointestinal cytoprotection, prevention of pressure sores, etc.) and a comprehensive medico-surgical team approach (orthopedic surgeons, neurosurgeons, ICU specialists, internists, etc.). Evaluation of the spine and spinal cord by NMR and CT scan allows precise assessment of the extent of CNS damage and provides additional guide-lines regarding efficient surgical reposition and spinal fusion. Ongoing experimental research in neurophysiology and neurobiochemistry of the brain and spinal cord is presently yielding some interesting results which hold out new hopes for functional recovery in some specific types of incomplete spinal cord trauma. 相似文献
68.
Double contrast examination constitutes an important element in radiological gastric examination. The author examines the history of the term "double contrast" and defines the designation of "double contrast examination". The exclusive use of the double contrast method reduces the diagnostic value of gastric X-ray examinations. Thus a method is suggested that will avoid the disadvantages of exclusive double contrast examination while adequately including double contrast in the gastric examination. This is done by using various methods - according to the problem posed - in order to achieve the double contrast. 相似文献
69.
70.
HJ Suschke 《Canadian Metallurgical Quarterly》1976,94(16):977-980
A multicentric open clinical trial was carried out by 8 practising specialists in dermatology or paediatrics in patients with bacterial skin diseases who were subjected to a systemic therapy with Syncillin (=Azidocillin). The Syncillin presentation for adults and schoolchildren was tablets of 750 mg each, and sachets of 125 mg or 250 mg for infants. The duration of treatment was 10 days. The parameters analyzed were bacteriological findings and the clinical course of disease. 71 (=74%) of the 96 patients included in this study were considered as cured, 21 (=22%) as improved and 4 patients (=4%) as unchanged. Bacterial identification was still positive in 10 cases after the termination of treatment. However, this did not preclude the assessments of "cured' (3 cases) or "improved' (7 cases). The tolerance of the preparation was considered as "very good' or "good' in 91 and as "poor' in 5 patients. The most common side effects were nausea and diarrhoea. Exanthema was observed in 2 cases. None of these side effects, however, made a discontinuation of medication necessary. The era of rational and well-directed chemotherapy enables good therapeutic approach also to bacterial skin diseases. 相似文献