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R D Wetzel 《Journal of clinical psychology》1976,32(1):4-13
Ninety-four Ss (28 attempters, 32 threateners and 34 psychiatric controls) rated 10 concepts twice 1 month apart. Extreme rating scores and factor (attitude) scores were derived from the ratings. Suicidal Ss made no more use of extreme ratings than did control Ss. Highly suicidal Ss did not differ from less suicidal Ss in extremeness of ratings. Suicidal Ss did report less favorable attitudes to the concepts life and myself and more favorable attitudes toward suicide. Highly suicidal Ss could be differentiated from less suicidal Ss on these concepts. Contrary to the theory of Neuringer and Lettieri, it was suggested that suicidal Ss do not show a general difference in cognitive style from other psychiatric patients. Concept rated and direction of rating are crucial. Significant changes in ratings occurred over time in conjunction with hopelessness, depression and self-rated suicide intent. It was suggested that these changes indicate that the ratings are a function of a state, rather than a stable trait. 相似文献
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J Debnath Sree Ram S Balani I Chakraborty PD Gupta RK Bindal P Sengupta 《Medical Journal Armed Forces India》2005,61(3):249-252
Background
To evaluate the usefulness and limitations of graded compression ultrasonography in the diagnosis of clinically equivocal cases of suspected acute appendicitis at the setting of mid zonal military hospital of India.Methods
A prospective study, graded compression ultrasonography with self localization was carried out with 3.5 MHz convex, 5 MHz convex and 7.5 MHz linear transducers (Wipro GE) in 69 clinically equivocal suspected cases of acute appendicitis. With maximal compression the anteroposterior diameter of appendix was measured from outer to outer wall. The main criterion for diagnosing appendicitis was demonstration of a non compressible appendix with anteroposterior dimension of 7mm or more.Result
Sonologically 36 (52%) cases were diagnosed as appendicitis. Anteroposterior outer diameter of inflamed appendices ranged from 7mm to 21mm (mean 10.5mm). 30 (83%) of 36 patients could accurately self localize the point of maximum tenderness. There were 01 false positive and 04 false negative cases. Sensitivity and specificity were 89.7% and 96.6% respectively. Positive and negative predictive values were 97.2% and 87.8% respectively. Alternative diagnoses were offered in 33 (47.8%) cases. Amongst these 33 cases, 14(42.4%) had abdominal pain of unknown origin. Gynaecologic, urologic and gastrointestinal aetiologies were established in 10(30.3%), 07(21.2%) and 02(6%) cases respectively.Conclusion
Graded compression ultrasonography superadded with self localization is an accurate means of diagnosing/excluding appendicitis in clinically equivocal cases of acute appendicitis and it is of great value in establishing alternative diagnoses.Key Words: Ultrasonography, Acute appendicitis 相似文献107.
Sachse A Wagner A Keller M Wagner O Wetzel WD Layher F Venbrocks RA Hortschansky P Pietraszczyk M Wiederanders B Hempel HJ Bossert J Horn J Schmuck K Mollenhauer J 《BONE》2005,37(5):699-710
Osteointegration of metal implants into aged organisms can be severely compromised due to reduced healing capacity of bone, lack of precursor cells for new bone formation, or osteoporosis. Here, we report on successful implant healing in a novel model of aged sheep in the presence of nonglycosylated bone morphogenetic protein 2 (BMP-2). Ewes of 8 to 12 years with significant radiologic and histologic signs of osteoporosis and adipocytic bone marrow received a cylindrical hydroxyapatite-titanium implant of 12 x 10 mm. BMP-2 has been produced as a bacterial recombinant fusion protein with maltose-binding protein and in vitro generation of mature BMP-2 by renaturation and proteolytic cleavage. A BMP-2 inhibition ELISA was developed to measure the in vitro release kinetics of bioactive human BMP-2 from immersed solid implant materials by using Escherichia coli expressed and biotinylated recombinant human BMP-2 receptor IA extracellular domain (ALK-3 ECD). The implants were placed laterally below both tibial plateaus, with the left leg implant carrying 380 microg BMP-2. Both implant types became integrated within the following 20 weeks. The control implant only integrated at the cortical bone, and little new bone formation was found within the pre-existing trabecular bone or the marrow cavity. Marrow fat tissue was partially replaced by unspecific connective tissue. In contrast, BMP-2-coated implants initiated significant new bone formation, initially in trabecular arrangements to be replaced by cortical-like bone after 20 weeks. The new bone was oriented towards the cylinder. Highly viable bone marrow appeared and filled the lacunar structures of the new bone. In mechanical tests, the BMP-2-coated implants displayed in average 50% higher stability. This animal model provided first evidence that application of nonglycosylated BMP-2 coated on solid implants may foster bone healing and regeneration even in aged-compromised individuals. 相似文献
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Experimentelle Untersuchungen über die Wirtsspezifität parasitischer Rundwürmer des jagdbaren Wildes
Zusammenfassung Es hat eine gewisse Bedeutung für die Praxis, inwieweit wechselseitige Ansteckungen mit parasitischen Würmern zwischen Haustieren und dem Wild möglich sind. Das Problem ist jedoch noch weitgehend ungeklärt. Von wenigen Einzelfällen abgesehen liegen auch keine experimentellen Untersuchungen dazu vor. Im vorliegenden Falle wurde daher versucht, durch Übertragungsversuche mit parasitischen Nematoden von Wisent, Rehwild, Muffelwild, Schwarzwild und dem Rebhuhn auf Haustiere einen Beitrag zur Klärung dieser Frage zu leisten. Die Ergebnisse und ihre Bedeutung für die Praxis werden besprochen.
Die Untersuchungen wurden mit Unterstützung der Veterinärverwaltung im Ministerium für Ernährung, Landwirtschaft und Forsten des Landes Nordrhein-Westfalen durchgeführt. 相似文献
Summary The problem, whether reciprocal transmissions between domestic stock and game animals are possible, has a certain importance, but is not completely solved uptil now. With the exception of some individual cases there is no experimental research about the matter. Therefore it had been tried here to transmit parasitic nematodes of European bison, roe deer, moufflon and partridge to domestic animals. The results and their importance are discussed.
Die Untersuchungen wurden mit Unterstützung der Veterinärverwaltung im Ministerium für Ernährung, Landwirtschaft und Forsten des Landes Nordrhein-Westfalen durchgeführt. 相似文献
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Rheological Changes After Stenting of a Cerebral Aneurysm: A Finite Element Modeling Approach 总被引:1,自引:0,他引:1
Ohta M Wetzel SG Dantan P Bachelet C Lovblad KO Yilmaz H Flaud P Rüfenacht DA 《Cardiovascular and interventional radiology》2005,28(6):768-772
Hemodynamic changes in intracranial aneurysms after stent placement include the appearance of areas with stagnant flow and
low shear rates. We investigated the influence of stent placement on blood flow velocity and wall shear stress of an intracranial
aneurysm using a finite element modeling approach. To assess viscosity changes induced by stent placement, the rheology of
blood as non-Newtonian fluid was taken into account in this model. A two-dimensional model with a parent artery, a smaller
branching artery, and an aneurysm located at the bifurcation, before and after stent placement, was used for simulation. Flow
velocity plots and wall shear stress before and after stent placement was calculated over the entire cardiac circle. Values
for dynamic viscosity were calculated with a constitutive equation that was based on experimental studies and yielded a viscosity,
which decreases as the shear rate increases. Stent placement lowered peak velocities in the main vortex of the aneurysm by
a factor of at least 4 compared to peak velocities in the main artery, and it considerably decreased the wall shear stress
of the aneurysm. Dynamic viscosity increases after stent placement persisted over a major part of the cardiac cycle, with
a factor of up to 10, most pronounced near the dome of the aneurysm. Finite element modeling can offer insight into rheological
changes induced by stent treatment of aneurysms and allows visualizing dynamic viscosity changes induced by stent placement. 相似文献