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21.
Cardiorespiratory reflexes (CRR) were studied by measuring heart-rate variation during 6 breaths/min respiration and a Valsalva maneuver in 232 insulin-dependent diabetic subjects. Abnormalities were found in 175 patients. During a 7-yr follow-up, 41 (23.4%) patients with abnormal and 2 (3.5%) with normal CRR tests died. The mortality rates of diabetic patients with abnormal autonomic function tests were 17% at 2.5 yr, 33% at 5 yr, and 40% at 7 yr, significantly higher (P less than 0.002) than in patients with normal tests (rates of 4.6, 4.6, and 13.8% at the respective intervals). Nerve conduction studies (NCS) were indicative of somatic neuropathy in 148 of 205 patients. Mortality rates were higher in patients with abnormal NCS than in those with normal results (P less than 0.025). Among patients with abnormal autonomic function, patients with a functioning pancreas transplantation (PTx) had better survival rates than patients with a failed PTx (P less than 0.005) and, on long-term follow-up, better rates than patients without PTx. Similar results were found comparing the same group of patients who had abnormal NCS.  相似文献   
22.
The inhibition of [35S]t-butylbicyclophosphorothionate ([35S]TBPS) binding to the GABAA receptor by the insecticide γ-hexachlorocyclohexane, lindane, was studied in several brain regions and using different membrane preparation methods, both in vitro and after dosing the animals with the chemical. In the latter studies, the amount of lindane remaining in the membrane suspensions used for binding assays was determined. In vitro data showed values of IC50 from 150 to 1675 nM, varying in function of the membrane preparation method used. This may account for the discrepancies in IC50 values found in the literature. IC50 values within the range of 150–250 nM were determined using extensively washed membranes from several brain regions, so no evidence arose for brain regional differences in the affinity of lindane for the TBPS binding site. After different schedules of acute treatment with lindane, we found a manifest relationship between the extent of the observable inhibition of [35S]TBPS binding and the lindane amount remaining in the membrane suspensions used for binding assays. This relationship was in good agreement with the in vitro data, so no support for an in vivo acute regulation of the binding site was obtained.  相似文献   
23.
Potassium cardioplegia was compared with normothermic, intermittent ischemic arrest in 30 patients undergoing multiple coronary artery bypass grafts. Group 1 comprised 15 patients in whom cold potassium cardioplegia with St. Thomas' Hospital solution was used. In Group 2 were 15 patients who underwent intermittent ischemic arrest during the construction of the distal anastomoses. Two myocardial transmural left ventricular biopsies were done in each patient. There was no operative mortality. Electron microscopical examination showed normal myocardial ultrastructure in both groups. In particular, mitochondria were well preserved in all samples. The postoperative electrocardiogram demonstrated a new Q wave in 1 patient in Group 2 whose level of the myocardial isoenzyme of creatine phosphokinase (CPK-MB) was within the normal range. The peak CPK-MB release in Group 1 was 23.2 +/- 20.1 IU and in Group 2, 19.9 +/- 15.1 IU. This difference was not statistically significant. The mean period of anoxic arrest in Group 1 was 49.5 +/- 15 minutes and in Group 2, 25.5 +/- 8 minutes (p less than 0.001). Total cardiopulmonary bypass time in Group 1 was 114.5 +/- 20 minutes and in Group 2, 90.2 +/- 16 minutes (p less than 0.01). It is concluded that both techniques can preserve myocardial subcellular architecture during multiple coronary artery bypass grafting in patients with normal left ventricular function.  相似文献   
24.
Abstract: Red cell phospholipids (PLs) were assessed in 11 patients with essential thrombocythemia and 5 patients with polycythemia vera. Platelet and plasma PLs were also determined in 10 of these patients, and the results were compared with studies performed in 16 healthy volunteers. The amount of platelet PLs in patients was similar to controls (556 ± 90 nmol/109cells, versus 481 ± 91 nmol/109cells), as was the percentage of the main specimens of these compounds, including phosphatidylserine (11.1 ± 0.8%), which is relevant for platelet procoagulant activity. We did not find differences between red cell PLs of patients (300 ± 60 nmol/109cells), versus controls (289 ± 71 nmol/109cells), and the sphingomyelin/phosphatidylcholine ratio in these cells was the same in both groups (0.75 ± 0.1). Finally, we did not detect any alteration in the amount of plasma PLs specimens.  相似文献   
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Effect of age and maturation on sudomotor nerve regeneration in mice   总被引:1,自引:0,他引:1  
This study demonstrates that regeneration of unmyelinated sudomotor axons in mice becomes progressively slower during aging. Identical lesions were made in mice aged 0, 2, 4, 6, 7, 24 and 60 weeks. The peroneal, sural and saphenous nerves were cut and tied to prevent regeneration. The sciatic nerve was then frozen at the thigh, leaving the hind paw completely denervated. By 7 days, sweat glands (SGs) of the paw had ceased sweating after pilocarpine injection. Subsequent regeneration of sudomotor axons was judged by the rate of return of pilocarpine sensitivity. SGs in the hind paws of normal newborn mice did not sweat at birth. Cholinergic stimulation first activated sweating at 13 days of life. The number of responsive SGs increased progressively to reach the adult level by 30 days. In one-week-old mice, whose sciatic nerve had been sectioned, the SG response to cholinergic stimulation was very delayed in time and reduced in number. Sweat glands of young mice, between 2 and 4 weeks of age, regained cholinergic sensitivity at a faster rate than mature animals and attained normal SG counts. Throughout a broad intermediate range of age in adulthood (7-24 weeks), the rate of sudomotor nerve regeneration was the same, but in older mice (60 weeks) it was slower and less complete.  相似文献   
28.
We studied four patients with ruptured aneurysms of the sinus of Valsalva. All were men with a mean age of 33 years. The presenting illness was insidious in three and of abrupt onset in one. Physical examination showed a continuous murmur in all. Chest X ray film showed moderate cardiomegaly. Electrocardiogram disclosed left ventricular hypertrophy. Echocardiogram revealed the site of the rupture which was corroborated by aortography. Two aneurysms ruptured to the right ventricle and two to the right atrium. All were corrected by surgery. All patients became asymptomatic.  相似文献   
29.
Gongylonema neoplasticum was identified in the oesophagus of 14 wild rabbits (Oryctolagus cuniculus) from Portugal. This is the first record of Gongylonema neoplasticum in a naturally infected lagomorph species in Europe. This paper presents the most relevant measurements of adult worms and some of their surface features seen by scanning electron microscopy. Epidemiological aspects of G. neoplasticum such as geographical distribution, host spectrum and biological features are discussed.  相似文献   
30.
Resumen La técnica del cultivo celular es la que ha permitido conocer el comportamientoin vitro de las células cancerosas. En esta revisión pretendemos introducir las peculiaridades básicas del cultivo celular, referido especialmente a líneas cancerosas mamarias, relacionar el origen de las líneas celulares más utilizadas en la investigación de este cáncer, mencionar las técnicas de laboratorio que pueden aplicarse sobre estos cultivos y ejemplificar la utilidad de las mismas, tomando como modelo diversos trabajos que estudian los efectos del factor de crecimiento epidérmico sobre líneas celulares hormonoindependientes de cáncer de mama.   相似文献   
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