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991.
Consultation may be viewed as a political-bargaining process in which actors seek to maximize at minimal cost expertise, organizational position, and organizational reputation. A view of consultation as political process allows for a shift in language in discussions of consultation. Such a language shift suggests shifts in the social meaning of the consultation process. Emphasis was placed on four suggested functions of consultation: definition and legitimation of a situation or of facts as problematic; raising the priority of an issue on the agenda of action in a consultee's agency;legitimation of deviant administrative behavior; and creation and sustenance of interagency linkages. A perspective is proposed that looks at the consequences as well as the intents of the process. This view of consultation can be studied empirically.  相似文献   
992.
Analysis of 5000 consecutive flexible fiberoptic sigmoidoscopies form the basis of this report. It is concluded that this method of examination of the distal large bowel is not only safe and comfortable for the patient but is a more appropriate examination than the rigid proctosigmoidoscopy because of the significant increase in pathologic material found. This examination has proven practical and acceptable in a multispecialty clinic setting and has completely replaced rigid proctosigmoidoscopy. Flexible sigmoidoscopy is now the standard "routine" examination of the rectum and distal colon. The rationale for this conclusion is presented in this timely report.  相似文献   
993.
Following consumption of a meal, 99% of the large food particles are emptied only after intragastric fragmentation has reduced their diameter to less than 2 mm. Anin vitro model was constructed to evaluate some of the factors which may play a role in the process of intragastric digestion. Gastric mixing of food was simulated in a silicone rubber tube (ID 19 mm) placed in a peristaltic pump. Peristaltic waves progressed upwards along the tube at a frequency of 0, 1, or 3/min, reducing the internal diameter of the tube to 5 mm. Cooked chicken liver particles (2–2.8 mm in diameter) were placed in the tube with one of the following: (1) 150 mM NaCl, (2) 150 mM HCl with or without pepsin, or (3) phosphate buffer at pH 7, 5.4, or 2.6 + pepsin. After 30 min, the extent of particle reduction and of solubilization of proteins were determined and expressed as percent of the initial liver weight. The diameter of liver particles was reduced to a greater extent in NaCl than in pH 7 buffer or acid solutions with or without pepsin. In contrast, the amount of proteins solubilized was enhanced two- to threefold by acid pepsin solutions compared to NaCl or pH 7 phosphate. The presentin vitro studies suggest that changes in motor and/or secretory activity of the stomach significantly modify intragastric digestion.  相似文献   
994.
Conditions causing a reduction of oxygen availability (anoxia), such as stroke or diabetes, result in drastic changes in ion movements, levels of neurotransmitters and metabolites and subsequent neural death. Currently, there is no clinically available treatment for anoxia induced neural cell death resulting in drastic and permanent central nervous system dysfunction. However, there have been some exciting developments in experimentally induced anoxic conditions where several classes of drugs appear to significantly reduce neural cell death. This report aims to provide the foundations for understanding both the basic mechanisms involved in retinal ischaemic damage and experimental treatments used to prevent such damage. We discuss the normal release, actions and uptake of the fast retinal neurotransmitters, glutamate and GABA, in the vertebrate retina. Immunocytochemistry is used to demonstrate that both glutamate and GABA are found in the macaque retina. Following this is a discussion on how ischaemia may enhance neurotransmitter release or disrupt its uptake, thus causing an increase in extracellular concentration of these neurotransmitters and subsequent neuronal damage. The mechanisms involved in glutamate neurotoxicity are reviewed, because excess glutamate is the likely cause of retinal ischaemic damage. Finally, the mechanisms behind four possible modes of treatment of neurotransmitter toxicity and their advantages and disadvantages are discussed. Hopefully, further research in this area will lead to the development of a rational therapy for retinal, as well as cerebral ischaemia.Abbreviations -KG -ketoglutarate - AAT aspartate amino transferase - AC amacrine cell - ACL amacrine cell layer - BC bipolar cell - CNS central nervous system - EAA excitatory amino acids - G'ase glutaminase - GABA -amino butyric acid - GABA-T GABA transaminase - GAD glumatic acid decarboxylase - GC ganglion cell - GCL ganglion cell layer - GDH glutamate dehydrogenase - gj gap junction - GS glutamine synthetase - HC horizontal cell - ILM inner limiting membrane - INL inner nuclear layer - IPC inter-plexiform cell - IPL inner plexiform layer - IS inner segment of photoreceptor - NFL nerve fibre layer - NMDA N-methyl-D-aspartate - OLM outer limiting membrane - ONL outer nuclear layer - OPL outer plexiform layer - OS outer segment of photoreceptor - Ox acetateoxaloacetate - RL receptor layer - SSAD succinate semi-aldehyde decarboxylase - Succinate SA succinate semi aldehyde - TCA cycle tricarboxylic acid cycle  相似文献   
995.
Lens tissue from a Morgagni cataract was examined by SEM and TEM. For SEM, after prefixation with glutaraldehyde and postfixation with the tannic acid/arginine/OsO4 non-coating (TAO) technique, and for TEM, after prefixation with glutaraldehyde, postfixation with OsO4/K4Fe(CN)6 and poststaining with uranyl acetate/lead citrate. The TAO technique seems to be a particularly suitable postfixation method for the SEM investigation of cararact tissue because of the presence of the protein structures present. The cortical region showed areas of radially, instead of concentrically, arranged lens fibres, degenerated lens fibres with holes (vacuoles), broken ball and socket connections between the lens fibres, and oval or spherical structures varying in size from 0.5–20 m, the largest resembling a golfball, arising from the cytoplasm of degenerating lens fibres. The smallest, 0.2–0.5 m, appear to have been expelled from the furrowed lens epithelium.  相似文献   
996.
A series of cures for ophthalmological diseases practised by saints are described, particularly the Saints Cosmas and Damian and the Saints Cyrus and John, the famous Anargyroi. In the xenones of the Byzantine churches and in the hospitals connected to these, therapeutic regimes, cures and surgical interventions took place at night during incubation, following the example of the ancient Asclepieia. This conclusion stands in spite of the fact that the authors describing the lives of the saints were often clergy who frequently cloak the true therapeutical cures by presenting them in a supernatural manner in order to stress the divine intervention of the saints. From the operations mentioned, it is clear that cataract surgery was among the operations most frequently practised.  相似文献   
997.
Summary In a study in mild hypertensives, the impact of mental and physical stress on plasma epinephrine (E), norepinephrine (NE), and on their ratio (NE/E) was evaluated. The effect of two-adrenoceptor blocking drugs, atenolol and bopindolol, on plasma catecholamine levels was also examined.Each stressful stimulus significantly increased the NE and E levels compared to rest. The increase was progressive from mental stress, through the handgrip test to the treadmill test. A slight decrease in the NE/E ratio was observed following mental stress and the handgrip test, while this ratio increased during the treadmill test.No significant impact of beta blocking treatment on catecholamine levels was observed under any test condition.  相似文献   
998.
Summary The uptake and localisation of O-(-hy-droxyethyl)-rutosides (HR) in the venous wall was studied in 8 patients undergoing crossectomy for a varicose long saphenous vein. The fluorescence of cross-sections of the vein wall was measured by laser scanning microscopy, based on the autofluorescence of HR. Four patients (treated group) received 2 × 1.5 g HR IV before surgery, and four (untreated patients) served as controls.Uptake of HR into the veins from treated patients was seen, with a mean fluorescence intensity of 80.9 units compared to 49.4 units in the untreated veins. The increase in fluorescence was clearly demarcated on the endothelial side of the vein wall.It is concluded that HR passes into the vascular wall, where it is localised in the endothelial and sub-endothelial areas.  相似文献   
999.

Objective

To assess the comprehensiveness of Medline and Embase computer searches for controlled trials.

Design

Comparison of articles found after an exhaustive search of the literature with the yield of a Medline or Embase search. This was performed for controlled clinical trials on the efficacy of three interventions: homoeopathy, ascorbic acid for common cold, and ginkgo biloba for intermittent claudication and cerebral insufficiency. The number of controlled trials found by exhaustive search of the literature was 107, 61 and 45, respectively.

Results

For homoeopathy, ascorbic acid and ginkgo the proportion of all trials found by Medline was 17%, 36% and 31% respectively and for Embase 13%, 25% and 58% respectively. After checking of the references in the Medline articles 44%, 79% and 76% of all trials were identified. After checking of the references in the Embase articles 42%, 72% and 93% of all trials were identified. About 20% of the articles was not correctly indexed. Of the best trials 68%, 91% and 83% could be found with Medline and 55%, 82% and 92% of the best trials were identified through Embase.

Conclusions

For the topics mentioned, Medline and Embase searches are sufficient to get an impression of the evidence from controlled trials, but only if references in the articles are followed for further evidence. If one wants to get a more complete picture, additional search strategies make sense. Of course, this picture may be different for other topics.  相似文献   
1000.
Spondylometaphyseal dysplasia was first described by Kozlowski et al. in 1967 as a new dysplastic bone disease, characterized by metaphyseal dysplasia associated with generalized platyspondyly in the vertebral column [1]. Kozlowski et al. have pointed out the autosomal dominant transmission of this disorder at that time. However, later reports showed that the manner of genetic transmission and the degree of the manifestation of the radiological findings could be variable and accordingly seven types of spondylometaphyseal dysplasia were described [2]. In this article, three cases displaying one of the rare forms of spondylometaphyseal dysplasia, type VII are presented and the diagnostic findings as well as the differential diagnostic criteria are discussed.  相似文献   
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