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61.
W N Kühn-Velten 《Andrologia》1992,24(2):109-111
In addition to the well-known control circuits involved in the regulation and adaptation of testicular androgen biosynthesis, it is proposed that two new control strategies are involved in the maintenance of steady-state testosterone secretion rates by testicular Leydig cells. Cytochrome P450XVII (steroid-17 alpha-monooxygenase/steroid-17,20-lyase), one key enzyme in steroid hormone biosynthesis, responds to external human choriogonadotropin stimulation with an oxygen-dependent and substrate flux-dependent inactivation and decomposition, and increased substrate availability decreases the efficiency of androgen formation in favour of abortive intermediate leakage. These results are discussed as a paradigm of substrate-dependent modulation of cytochrome P450 activities. 相似文献
62.
Temporary closure of the abdominal wall (laparostomy) 总被引:2,自引:0,他引:2
A. Schachtrupp V. Fackeldey U. Klinge J. Hoer A. Tittel C. Toens V. Schumpelick 《Hernia》2002,6(4):155-162
The definitive closure of the abdominal wall, i.e., a closure of the fascial layer and skin may not be favorable in the treatment
of numerous surgical conditions, e.g., peritonitis, trauma, or mesenteric ischemia. In these cases, the abdominal wall is
temporarily closed, and a laparostomy is created to facilitate re-exploration or to prevent abdominal compartment syndrome.
Regarding the technique and material used for the temporary closure, no prospective randomized data exists, but mesh materials
are commonly used. They provide drainage of infectious material, permit visual control of the underlying viscera, facilitate
access to the abdominal wall, preserve the fascial margin, enable healing by secondary intention, and allow mobilization of
the patient. In the case of decreasing intra-abdominal pressure, meshes can be trimmed to centralize the rectus muscle and
to facilitate definitive closure. Non-absorbable meshes have been frequently reported to cause enteric fistulae and persistent
infection necessitating mesh explantation. While these infectious complications appear to occur less frequently with the use
of absorbable materials, these meshes will finally lead to an incisional hernia, requiring repair with non-absorbable mesh
after a period of 6–12 months. Nevertheless, in the complex situation requiring a temporary abdominal wall closure, use of
absorbable mesh material is common and represents the state of the art.
Electronic Publication 相似文献
63.
Annette Anderton 《Journal of human nutrition and dietetics》1994,7(1):53-60
The HACCP (hazard analysis critical control point) concept is now widely applied in the food industry and provides a structured and critical approach to the identification and control of hazards that may affect food safety. It has shifted the emphasis for control from retrospective end-product testing to the effective control of raw materials and key processing operations.
This paper discusses how the HACCP approach can be applied to enteral feeding. This involves each unit assembling a multidisciplinary team of personnel involved in enteral feeding. This team will then carry out a detailed analysis of the process from selection of ingredients and feeding systems through to consumption of the feed by the patient by constructing a flow chart that relates specifically to each unit. They can then identify and assess the hazards associated with the handling of the product at each stage in the process. This will enable them to identify the points where control over an identified hazard can be achieved (critical control points, CCP) such as quality of ingredients, design of administration systems, preparation and distribution of the feeds and the procedures involved in the assembly and manipulation of the systems. Control and monitoring procedures can then be specified and implemented at relevant stages in the process. The major strengths of the HACCP procedure are that it entails a team effort from key personnel involved in the full range of activities associated with the product and each detailed analysis is specific to each unit's practices and resources and can be continually reviewed and modified in response to changing circumstances. 相似文献
This paper discusses how the HACCP approach can be applied to enteral feeding. This involves each unit assembling a multidisciplinary team of personnel involved in enteral feeding. This team will then carry out a detailed analysis of the process from selection of ingredients and feeding systems through to consumption of the feed by the patient by constructing a flow chart that relates specifically to each unit. They can then identify and assess the hazards associated with the handling of the product at each stage in the process. This will enable them to identify the points where control over an identified hazard can be achieved (critical control points, CCP) such as quality of ingredients, design of administration systems, preparation and distribution of the feeds and the procedures involved in the assembly and manipulation of the systems. Control and monitoring procedures can then be specified and implemented at relevant stages in the process. The major strengths of the HACCP procedure are that it entails a team effort from key personnel involved in the full range of activities associated with the product and each detailed analysis is specific to each unit's practices and resources and can be continually reviewed and modified in response to changing circumstances. 相似文献
64.
The relationship of perceived control over daily uplifts and hassles to depression and restraint was examined in a sample of 140 middle-class sixth graders. Results indicated that greater control over uplifts was associated with better functioning and lower control over hassles with poorer functioning, even after partialing out the respective number of uplifts and hassles reported. Moreover, when directly compared, control over uplifts showed more powerful associations with adaptational outcomes than did control over hassles. In a separate analysis, the number of uplifts over which children reported high control showed opposite relationships to adaptational outcomes than did the number of uplifts over which children reported low control. A different pattern appeared for hassles. Although the number of hassles with low control was associated with poorer functioning, the number of hassles over which children had high control was unrelated to adaptational outcomes. The possibility that control operates somewhat differently for positive and negative events is discussed.This research was supported by a grant to the second author from the Stanford Center for the Study of Families, Children and Youth. The authors are grateful to Rachelle Hacket for data analysis, Tom Gehring for data collection, and Susan Nolen-Hoeksema for critical comments. 相似文献
65.
While much research has been devoted to the implementation and application of Volterra and Wiener functional series expansions
in the identification and characterization of biological systems, little effort has been focused on the fundamental problem
of interpreting the resulting kernels. This paper describes the application of the series to the components of a known model
of the human pupil control system. As more complicated elements are put together, insight into kernel interpretation is built
up incrementally until the total system is identified. Practical limitations and methods are also discussed. 相似文献
66.
Shuji Iritani 《Neuropathology》2007,27(6):604-608
The neuropathology of schizophrenia remains obscure despite the fact that many neuropathologists have investigated this area for over 100 years. While remarkable progress has been made in the neuropathological study of neurodegenerative diseases including Alzheimer's disease, progress in studying the neuropathological entity of schizophrenia has not kept pace; the phrase “schizophrenia is the graveyard of neuropathologists” has been stated in the field. Since the 1980s, the morphological or functional abnormalities in the brains of schizophrenia patients have been reported by means of CT or MRI and with advanced functional brain image technology such as positron emission tomography or single photon emission computed tomography. Results from such imaging studies have led to neuropathological examination of the post mortem brains of schizophrenia patients being undertaken again. These neuroimaging studies have influenced the neuropathological investigation of the schizophrenic brain. Not only the classical microscopic observation of neuropathology, but also measurement and statistical analysis using computer imaging software or using immunohistological techniques has been performed. Based on the neuropathological studies of schizophrenia over the last 20 years, it is clear that schizophrenia is not a pure functional disease without organic factors. Reports of neuropathological abnormalities in the post mortem schizophrenic brain indicated they were found in almost all areas of the brain, but there are more reports describing the temporal lobe and frontal lobe compared to those describing other areas of the brain. These observed neuropathological abnormalities are explained rationally by the hypothesis of a neurodevelopmental disorder in this disease. In recent molecular biology studies, several putative candidate genes were reported, and some of these genes might have the function of neurodevelopment or making neuronal networks. It is important to consider together these findings with morphometric studies in neuropathological observation, neuroimaging studies and genome studies to pursue the etiology of schizophrenia from various perspectives. 相似文献
67.
论网络化时代电视教材的重要性 总被引:7,自引:3,他引:4
郭玉军 《中国医学教育技术》2003,17(2):70-72
针对教学实践中重视计算机辅助教学忽视电视教材的倾向,本文通过对网络时代中电视教材的作用和地位的分析,阐述了加强计算机辅助教学的必要性和加强电视教材制作及应用的重要性以及二者间的关系。 相似文献
68.
69.
温州地区近6年907例精神病司法鉴定案例分析 总被引:2,自引:0,他引:2
石华孟 《神经疾病与精神卫生》2004,4(5):343-345
目的 探讨近 6年精神病司法鉴定案例的特征。方法 对浙江温州鹿城精神病医院1998~ 1999年 (A组 ) 2 0 2例 ,2 0 0 0~ 2 0 0 1年 (B组 ) 36 8例 ,2 0 0 2~ 2 0 0 3年 (C组 ) 337例进行对照研究。结果 近 6年 ,女性和无业构成比上升 (P <0 .0 1)。责任能力评定下降 ,服刑能力、民事行为能力评定上升 (P <0 .0 1)。精神损伤评定构成比上升 (P <0 .0 5 )。诊断为精神分裂症、情感性精神病逐年上升(P <0 .0 1)。无责任能力评定上升 (P <0 .0 1) ,完全责任能力评定下降 (P <0 .0 1)。法院委托鉴定上升 (P <0 .0 5 )。结论 近 6年中精神病司法学呈现不同的特点 ,并逐步向规范化、法规化迈进 ,服务范围和对象将会扩大 相似文献
70.
本文应用电力载波技术,实现远端时钟的中央控制。系统通过电力载波芯片从电力线上收发控制信号,中央控制端发送的时钟校准信号到电力线网络,接人网络的远端时钟接收到校准信号后,由微处理器解析数据调整受控端时钟显示,从而实现时钟的中央控制。 相似文献