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91.
The age dependence of ATP hydrolase activity and oligomycin sensitive passive proton conduction in sonicated submitochondrial particles of rat brain and rat heart has been investigated. The results show an increase of Vmax of the ATP hydrolase activity and decrease of oligomycin sensitive passive proton conduction with increase of the age of rats from 3 to 6 months. Decrease of ATPase activity and increase of oligomycin sensitive proton conduction occur with further aging to 24 months. Immunoblot analysis shows that both the F(1) and F(0) contents of mitochondria vary with the age of rats, the former exhibiting relatively larger changes.  相似文献   
92.
Tactile pattern recognition of ten different patterns which were engraved upon 4 x 4 cm plastic plaquettes with one hand and thereafter drawing with the other or the same hand was tested in 21 patients with a mild stage primary degenerative presenile onset dementia of Alzheimer type (DAT) and in 14 patients with a questionable dementia on the background of a chronic cardiovascular disease (CVD) in comparison to 15 healthy subjects of the same age (51 years old, elder controls, (EC)) and 16 younger subjects (22 years old, younger controls, (YC)). Patients made about four times more errors than the EC group. Duration from the begin of touching to the end of drawing was significantly longer in patients than in controls. In a second task the subjects had to recognize four subsequent patterns, then to perform a standard multiplication task and afterwards to draw all four patterns in their correct sequence. Patients made about ten times more errors in pattern recognition and series reproduction than age-matched controls.  相似文献   
93.
The efficiency and risks of a method that allows closed-chest decannulation of an intraoperatively inserted cardiac-assist balloon catheter are examined. The technique involves direct insertion of the balloon catheter into the ascending aorta under the protection of an indwelling silastic tourniquet. At the discretion of the surgeon, the tourniquet may be left in place or removed later through a small infrasternal incision. This method was applied for 6 years, from May 1985 to June 1991, in 18 patients. Satisfactory cardiac assistance was achieved in every patient, and no early or late complications or deaths were attributable to the technique. At the time of this report, 9 patients are still alive. The author recommends the application of the procedure whenever, in the course of open-heart operations, cardiac-assist intraaortic balloon pulsation becomes necessary and conventional transfemoral insertion is either impossible or inadvisable.  相似文献   
94.
There have been only 58 angiographically documented reports of transmural myocardial infarction due to closed-chest trauma. None of these cases has been treated by percutaneous transluminal coronary angioplasty. We report the case of a 40-year-old man who developed an anterior-wall myocardial infarction secondary to blunt chest trauma suffered in an automobile accident. Angiographic study performed 2 months after the injury revealed an isolated total obstruction of the left anterior descending coronary artery. The patient was judged a good candidate for balloon angioplasty, but total reocclusion occurred within 24 hours of the procedure and a 2nd attempt did not restore patency. Surgical revascularization was performed a week later. A year after his injury, the patient remains asymptomatic and is back at work. Despite the failure of percutaneous transluminal coronary angioplasty in its 1st application to coronary artery repair after blunt chest trauma, we believe it to be the treatment of choice in young patients and in single-vessel disease.  相似文献   
95.
The author reply     
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96.
Five iridoids have been isolated from the aerial parts of SCAEVOLA RACEMIGERA D?niker, namely, loganin, loganic acid, sylvestroside III, cantleyoside, and scaevoloside. This latter is a novel compound whose structure 1 has been elucidated on the basis of its spectral data, mainly (1)H- and (13)C-NMR.  相似文献   
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99.
Brain-derived neurotrophic factor (BDNF) is involved in the differentiation and the survival of neurons. It has also been shown to be associated with the regrowth of neurons of damaged spinal cord and the modulation of ionic currents by acting on sodium channels and NMDA receptors through tyrosine kinase B (TrkB) receptors. We investigated the effects of BDNF on rhythm generation induced by disinhibition in dissociated cultures from embryonic rat spinal cord (E14), with extracellular multisite recordings (MultiElectrode Arrays, MEAs) or intracellular patch-clamp recordings. Exogenous BDNF had only minor effects on the bursting by increasing the activity during the burst. This increase of activity is suggested to be mediated by a potentiation of the postsynaptic NMDA receptors because it has been found that BDNF potentiates the NMDA-evoked depolarization in cultures incubated with BDNF for 10 min. Possible direct effects of BDNF on sodium channels were also investigated by local application of BDNF to the soma of patched neurons but no depolarization was observed. Long-term application of BDNF strongly decreased the activity during the burst and also the number of active electrodes, possibly due to a decrease in network density.  相似文献   
100.
The study presents the results from intraoperative frozen section assessment of axillary sentinel lymph nodes (SLNs) in breast cancer. Routine histological frozen sections from one level were used, two sections stained with haematoxylin and eosin. Immunohistochemistry for cytokeratins was applied to the permanent SLN paraffin sections only. Axillary dissection was performed on all SLN-positive cases regardless of the size of the metastatic deposits. With a detection rate of 83%, 272 patients entered the study over a period of 46 months. A total of 61 cases were SLN positive by frozen section analysis. The paraffin sections gave an additional 23 SLN-positive cases. The false-negative rate for frozen sections was then 27% (23/84). Micrometastases were found in 28 of 84 cases, and macrometastases in 56. The false-negative rate of frozen sections for micrometastases was 71% (20/28), and for macrometastases 5% (3/56). A total of 73% (61/84) of the patients underwent axillary surgery as a one-step procedure.  相似文献   
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