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991.
24 hour ambulatory electrocardiography was performed in a representativegroup of people born in 1897. Out of 73 people included in thestudy, 22 were without known heart disease, 15 had definiteischaemic heart disease (IHD) and 36 symptoms of possible cardiacorigin. An R-R interval in excess of 2000 ms was seen in only3 subjects and Wenckebach A-V block in only one. One subjectwithout a history of syncope had a nocturnal episode of completeA-V block with an escape interval of 8000 ms. The most strikingdifference between healthy subjects and patients with IHD wasthe higher number of patients with more than 1000 ventricularpremature beats (VPBs) per 24 hour and ventricular coupletscompared with the number of healthy subjects with such findings.At follow-up two years later 11% had died, with the highestmortality in patients with IHD (33%), and out of 8 patientswith IHD who had more than 1000 VPBs per 24 hour, 4 (50%) haddied compared with only one (14%) of those with less than 1000VPBs. Our results seem to indicate that more than 1000 VPBsper 24 hour is a very unusual finding in healthy 85 year oldindividuals. When it occurs in very old people, it is usuallyin connection with IHD, and in this setting it signifies a poorprognosis.  相似文献   
992.
Summary Report on a family of three brothers in which the prevailing features of the clinical findings were those of Friedreich's heredo-tabes.Histologically besides the degeneration of the peripheral proprioceptive neurone and of the ventral spinocerebellar tract, several other systems proved affected.For similar categories of cases, it does not seem useful to introduce a complicated terminology, and thea potiori denomination of the classical syndrome should be retained. Yet, both the clinical and the pathological examinations have to seek carefully in every individual case for the presence of pathological features which do not belong to the basic syndrome, and note them in the characterisation of the case. Although in systemic degeneration it is the most distal part of the neuronal unit where degeneration starts, the source of it lies in the originating nerve cell. For the pseudosystem-degenerations in the sense of Seitelberger this holds true only exceptionally, if at all.Dedicated to Prof. F. Seitelberger on the occasion of his seventieth birthday  相似文献   
993.
The aim of the present investigation was to discover whetherdisturbed left ventricular (LV) function limits renal replacementtherapy in patients with juvenile onset diabetes mellitus. Seventeenpatients given functioning kidney grafts were studied non-invasively(M-mode echocardiography, apexcardiography, phonocardiography)before renal transplant and an average of six, 13 and 44 monthsafter transplant. The main pretransplant findings were pronouncedLV hypertrophy with impaired diastolic LV function (prolongedrelaxation time + signs of decreased LV distensibility) anda hyperdynamic circulation. Most of these abnormalities were significantly less severe aftersuccessful kidney transplantation. LV mass decreased by 37%44 months after transplant (p<0.01) and LV diastolic andsystolic volumes decreased with a subsequent increase in ejectionfraction from 0.65 to 0.78 (p<0.01). The LV distensibilityand filling pattern improved significantly while the prolongedrelaxation time was unchanged. These findings imply that pretransplant disturbances in LV functionare related more to factors such as hypertension, volume overloadand uraemia than to diabetes per se because no pronounced improvementin the metabolic disorder resulting from diabetes can be expected,even after the most successful transplant. Disturbed LV functionshould not, therefore, exclude uraemic diabetics from renalreplacement.  相似文献   
994.
Summary 1-Methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) is a selective neurotoxin which produces degeneration of the nigrostriatal bundles in the central nervous system of man and animals. In these areas of the brain are concentrated the receptor binding sites for [3H]MPTP. 1-Alkyl-4, 4-diphenylpiperidines displace [3H]MPTP from these binding sites with K1 values in the micromolar range. The t-butyl analogue in this class of substances, budipine, is a novel therapeutic agent for Parkinsonism whose mechanism has not yet been fully clarified. The affinity of budipine for the MPTP receptor binding site was determined as a K1 value of 2.2M. Other 4, 4-diphenylpiperidine derivatives such as 1-methyl-4, 4-diphenylpiperidine and 1-i-propyl-4, 4-diphenylpiperidine have substantially lower affinities. Monoamine oxidase inhibitors such as deprenyl, pargyline and harmaline have affinities to the MPTP receptors which parallel their affinity for the B type of monoamine oxidase (MAO B). This supports the theory that the MPTP receptor binding sites is identical with membrane bound MAO B.  相似文献   
995.
Increased lung vascular permeability leading to increased plasma protein extravasation and accumulation (PPA) is a characteristic feature of acute lung injury. Using a previously described technique, PPA was monitored in the lungs of patients with the adult respiratory distress syndrome (ARDS) — an extreme example of acute lung injury in man. An external radiation probe detector was used to monitor the pulmonary accumulation of the plasma protein transferrin radiolabelled in-vivo with 113mIn. Ten patients with ARDS exhibiting increased PPA indices (>1.0x10-3/min) were given an intravenous infusion of terbutaline (7 g/kg) over 30 min. Of the four patients in whom the post-drug PPA indices remained within the ARDS range, none survived, whilst five of the six patients in whom the post-drug PPA indices were reduced to below 1.0x10-3/min survived. PPA indices prior to the administration of terbutaline were not significantly different between the survivor (n=5) and non-survivor (n=5) groups. There was a significant decrease in the PPA indices following terbutaline in survivors (p<0.01) but not in non-survivors. Thus beta-2-agonists in therapeutic doses can inhibit increased lung vascular permeability in man. These findings may have prognostic and therapeutic implication for beta-2-agonists in ARDS.  相似文献   
996.
Administration of 60 ppm cadmium (Cd) in drinking water from the 1st to the 20th day of gestation to female rats did not affect the viability, body weight gain, food, and water consumption of offspring. The blood hemoglobin level was reduced in 2-week-old females and males but not in 16-week-old offspring. Hematocrit and serum glucose level were not affected at either age. Cadmium concentration in the intestinal wall was increased in both age groups, with marginal uptake in other organs. A decrease in copper (Cu) concentration was found in the brain of 2-week-old offspring of both sexes and of 16-week-old females. The brain zinc (Zn) concentration was decreased only in 16-week-old animals. The physical and neuromuscular development of offspring before weaning was not impaired by maternal Cd treatment. The alterations in Cu and Zn metabolism were associated with reduced locomotor activity and affected open-field behavior in adult offspring of either sex and with decreased avoidance acquisition in adult female offspring.The results obtained suggest a relationship between the reduced brain Cu and Zn levels and CNS dysfunction in adult offspring of female rats exposed to Cd during gestation.  相似文献   
997.
The effects of several antidepressants on the release of (3H)-norepinephrine (NE) from homogenates of rat cerebral cortex were studied. A continuous superfusion collection system was used in order to differentiate these effects from effects on reuptake. Amitriptyline, maprotiline, mianserin, and trazodone produced a statistically significant decrease in spontaneous tritium efflux when present in the superfusion medium at a concentration of 1.0 M. The other antidepressants studied had no effect. We used a buffer with the K+ concentration raised to 56 mM as a model of depolarization-induced release. Desipramine, fluoxetine, and iprindole (again at 1.0 M) caused a significant decrease in this measure. These results indicate that some of both the tricyclic and atypical antidepressants may alter spontaneous or depolarization-induced release of NE.This work was supported in part by a grant from the Pharmaceutical Manufactures Association Foundation-Medical Student Research Fellowship  相似文献   
998.
Using the "canine model of the completely ischemic brain regulated with a perfusion method," the effects on cerebral ischemia of vitamin E, which is known to act as an antioxidant, were investigated. After pretreatment with vitamin E by oral or intravenous administration, cerebral blood flow was reduced to 1/10th the normal state and, 1 hour later, allowed to return to normal. Subsequent changes in electrical activity were observed, and the effects of vitamin E were evaluated. In the control group, no recovery of electrical activity was seen. In the groups given vitamin E, the recovery time was significantly shortened in the dogs given 30 mg/kg of vitamin E intravenously. Furthermore, in the groups treated with vitamin E, distinct recovery of electroencephalographic potentials at 3 hours after recirculation was apparent. These effects were more favorable in the case of intravenous administration than in the case of oral administration. These experimental results indicate that the administration of vitamin E is effective in protecting the brain from cerebral ischemia.  相似文献   
999.
After an injury to the right ring finger, a 44-year-old woman experienced pain in the distal interphalangeal joint. A subcutaneous mucoid cyst was noted near the joint. The x-ray films revealed no fracture but a narrowing of the joint space and a well-defined radiolucent area in the ulnar condyle of the middle phalanx. The biopsy specimen of this area excluded infection or tumor and revealed active osteogenic remodelling. These elements permitted a diagnosis of distal interphalangeal osteoarthritis that was associated with highly localized Sudeck's dystrophy (also called " parcellar algodystrophy"). This unusual case suggests the possibility that this dystrophy might be favored by an "osteoarthritic terrain" and might also play a role in the evolution of the osteoarthritis.  相似文献   
1000.
Summary Hypotensive brain stem necrosis is reported in a stillborn. Additional postmortem findings included evidence of intrauterine distress, shock, and a pure blood culture of group B -hemolytic streptococci. These findings suggest group B -hemolytic streptococcal sepsis in utero, with a subsequent episode of transitory circulatory failure prior to intrauterine demise.  相似文献   
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