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1.
Jairo R. Martinez Marvin D. Rausch James C. W. Chien Helmut G. Alt 《Macromolecular chemistry and physics.》1989,190(6):1309-1317
Acetylene was polymerized by (η-Cp)2Ti(PMe3)2 at room temperature to give predominantly trans-polyacetylene. All properties are within the ranges reported for polyacetylene produced with Ti(OBu)4/AlEt3 as catalyst. 相似文献
2.
ZQ Yin MD SG Crewther PhD B Pirie BSc DP Crewther PhD 《Clinical & experimental ophthalmology》1997,25(4):107-109
Purpose: It was investigated whether alterations in neuronal structure and function occasioned by strabismic amblyopia also may be reflected in alterations in the expression on Y type neurons of a Cat-301 antibody sensitive antigen in the lateral geniculate nucleus (LGN) and cortex of our cat model of strabismic amblyopia. Methods/Results: The percentage of positively labelled cells was reduced in LGN laminae that received input from the deviated eye in strabismic amblyopic cats compared with normal cats. In the strabismic cortex, the density of immunopositive neurons was significantly reduced compared with normal, the effect being most pronounced in layer IV Conclusions: Despite previous physiological recordings indicating a decrease in X-cell associated acuity in strabismic amblyopia, the present findings imply that the changes in the early visual experience occasioned by strabismus also produce specific molecular changes in theY neuronal class. 相似文献
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M P Arpin M Alt J C Kheiralla G Chabrier M Welsch J L Imbs M Imler 《La Revue de médecine interne / fondée ... par la Société nationale francaise de médecine interne》1991,12(4):309-311
We report the cases of two patients who, after prolonged amiodarone therapy developed hyperthyroidism and immune haemolytic anaemia. Antibodies were of the IgG type and non-specific at elution. A search for other causes of haemolytic anaemia with positive Coombs' test gave negative results. Antiamiodarone antibodies have recently been discovered; they reflect an immunological disturbance due to this drug and might be responsible for some of the undersirable effects of amiodarone. In our patients, hyperthyroidism and haemolytic anaemia were induced by a dual mechanism: accumulation of amiodarone and induction of an effect of this drug on the immune system. 相似文献
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Although an exercise-induced increase in blood temperature has been well-known for some time, there was still some doubt whether the change in central venous blood temperature with short-lasting and repetitive physical exercise can be measured and utilized by a temperature controlled pacing system. We studied the central venous blood temperature with short-lasting and repetitive exercise in ten healthy young volunteers and in ten pacemaker patients. The blood temperature was measured intracardially while they walked upstairs. A height of 20 m was covered within 100 +/- 5 s. An oxygen uptake of 27 ml/min/kg was calculated for this level of exercise. After walking upstairs once, the volunteers had an increase in central venous blood temperature of 0.3 degrees C and the pacemaker patients of 0.37 degrees C. After walking upstairs three times, the volunteers had an overall rise in blood temperature of 0.67 degrees C and the pacemaker patients of 0.86 degrees C. Thus, the central venous blood temperature shows a pronounced, measurable increase with short-lasting exercise as well. However, the rises in blood temperature accumulate with repetitive exercise, as the duration of exercise (100 s) when walking upstairs once is not sufficient for a new level of temperature to be reached according to the level of exercise. Thus, a temperature controlled pacing system should take these complex changes into consideration. 相似文献
9.
A comprehensive anatomic and radiographic analysis of the peribursal fat plane in 12 cadavers confirmed that the fat plane seen on radiographs represents extrasynovial fat lining the subacromial bursa and documented the anatomic relations of the bursa. A three-part retrospective clinical evaluation of rotator cuff tears, calcific tendinitis, and rheumatoid arthritis was performed. Two osteoradiologists blindly graded the appearance of the peribursal fat plane with the shoulder in external versus internal rotation in 21 patients with arthrographically intact rotator cuffs and 21 patients with disrupted rotator cuffs. The peribursal fat plane was seen better with disrupted rotator cuffs. The peribursal fat plane was seen better with the shoulder in internal rotation and was seen in 60% of control subjects but only 21% of patients with rotator cuff tears. Partial or complete obliteration of this fat plane is a sensitive (79%) but less specific (60%) indicator of rotator cuff tears. Obliteration of the peribursal fat plane by inflammatory processes in adjacent tissues, including calcific tendinitis and rheumatoid arthritis, occurred with a high frequency. 相似文献
10.
Visceral leishmaniasis: another HIV-associated opportunistic infection? Report of eight cases and review of the literature 总被引:5,自引:0,他引:5
J Altés A Salas M Riera M Udina A Galmés J Balanzat A Ballesteros J Buades F Salvá C Villalonga 《AIDS (London, England)》1991,5(2):201-207
Visceral leishmaniasis (VL) is considered an opportunistic infection in immunocompromised patients. We review the clinical, laboratory, and therapeutic data in 63 patients (eight new cases and 55 cases reported in the literature) with Mediterranean VL (kala azar) and HIV-1 infection to determine whether VL should be considered an opportunistic infection in HIV-infected adults. We conclude that: (1) in areas where both leishmaniasis and HIV-1 infection are endemic, VL may be more frequent among HIV-infected adults; (2) in HIV-infected patients, the clinical picture did not differ significantly from classical kala azar, although it often ran a recurrent course, with resistance to antimonial therapy. We propose the inclusion of VL in the IVC-2 subgroup of the Centers for Disease Control (CDC) clinical classification of HIV-1 infection while prospective and larger studies further define whether there are clinical presentations that could justify adding VL to the list of opportunistic infections indicative of AIDS. 相似文献