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111.
If current is flowing in cardiac tissue, and if the myocardial fibres approach a sealed boundary at an angle, then the tissue within a few length constants of the boundary is polarised. This polarisation occurs when the cardiac tissue has different anisotropy ratios in the intracellular and extracellular spaces. This new mechanism of tissue polarisation is demonstrated using a simple, analytical model, and it is shown quantitatively that this polarisation can be nearly as large as that occurring near an electrode.  相似文献   
112.
Magnetoenterography (MENG) is a new, non-invasive technique that measures gastrointestinal magnetic signals near the body surface. This study was undertaken to evaluate the temporal and spatial characteristics of the magnetic signals generated by gastric and duodenal slow wave activity. The gastrointestinal magnetic fields of eight normal subjects were measured for 60 minutes in both the fasting and fed state using 36 magnetic sensors simultaneously. The results were displayed as a succession of maps over time showing the temporal evolution of the spatial distribution of the signal over the upper abdomen. In all subjects, slow wave activity of the stomach centred at 3.0 +/- 0.5 cycles min-1 in both the fasting and fed state was observed. The duodenal signal at 11.0 +/- 1.0 cycles min-1 was observed in four subjects. The spatial distribution of these two signals is distinctly different. The observed spatial and temporal variations are described in terms of a model used previously to explain the potentials observed in electrogastrography (EGG).  相似文献   
113.
The purpose of these experiments was to study the incidence of stress ulcers in restrained rats and to correlate it with hypothalamic and adrenal cortical and medullary activity, with and without vagotomy. A total of 217 adult rats were used, grouped into 56 sets, and distributed at random in 5 experimental groups. Restraint was followed by a 79% incidence of ulceration in the glandular portion of the gastric mucosa. Vagotomy made these worse (p<0.01). Hypothalamic levels of catecholamines and serotonin showed no significant changes. Urinary measurements revealed decreased excretion of 17-ketosteroids (p<0.001), increased excretion of uropepsinogen (p<0.01), and no significant changes in vanillylmandelic acid among the rats submitted to immobilization. In the adrenal glands of stressed animals, there was a decreased level of catecholamines (p<0.01) and no significant changes in corticosteroid content (17-ketosteroids). These results suggest that hypothalamic stimulation and the participation of the adrenal glands are not essential factors in the pathogenesis of restraint-induced experimental stress ulcer.  相似文献   
114.
The acrosome reaction of human spermatozoa was induced by changes of temperature. Spermatozoa were collected from fertile donors and a patient group, and selected by the "swim-up" method. The spermatozoa were treated in two different ways: Protocol I: 24 hours at room temperature followed by additional incubation at 37 degrees C for 3 hours (control), and protocol II: 24 hours at 4 degrees C followed by additional incubation at 37 degrees C for 3 hours. The acrosome reaction of the viable spermatozoa was evaluated by a new method utilizing indirect immunofluorescence with anti-outer acrosomal membrane antibodies and exposure to a hypo-osmotic medium. In fertile donors as well as in the patient group, significant induction of the acrosome reaction (20%) was evident after exposure to low temperature (4 degrees C). The spontaneous rate of acrosome reaction in the control group was below 7%.  相似文献   
115.
Summary Therapeutic trials with hemodialysis have been performed in three cases of chronic schizophrenia. The severely ill patients had been hospitalized for more than ten years and had not responded to different types of conventional somatic treatment. Psychopathology was evaluated by use of the IMPS, BPRS, and NOSIE scales. No improvement could be observed as a consequence of 12 (11 in one case) hemodialysis treatments. Rather, some deterioration occurred in two of the patients. This result is not in accord with the markedly positive findings of Wagemaker and Cade (1977). However, further studies appear necessary to render final conclusions.Supported by a Stipendium of the Fritz-Thyssen-Foundation, Cologne  相似文献   
116.
Precancerous lesions of the stomach   总被引:1,自引:0,他引:1  
The etiology of stomach cancer in relation to preexisting mucosal alterations is described and discussed from a review of the literature and our own previously reported experience. The incidence of cancerization or malignant change of gastric polyp, chronic gastric ulcer, and chronic gastritis varies considerably from researcher to researcher. Clinical follow-up studies in many cases of gastric polyp and chronic ulcer discovered in the mass survey examination of the stomach revealed incidences of malignant degeneration of 2.3% of the gastric polyp cases and 2.06% of the gastric ulcer cases.
Résumé Les relations entre altérations préexistantes de la muqueuse et étiologie du cancer gastrique sont décrites et discutées, avec revue de la littérature et de notre expérience personnelle. La fréquence des cancérisations ou des dégénérescences malignes des polypes gastriques, de l'ulcère gastrique chronique et de la gastrite chronique est éminemment variable d'une étude à l'autre. Les follow-up de populations soumises à des examens systématiques de dépistage indiquent que la fréquence des dégénérescences malignes est de 2.3% pour les polypes gastriques et de 2.06% pour l'ulcère gastrique.
  相似文献   
117.
A retrospective study was carried out by reviewing the files of 100 patients who had undergone radical mastectomy and 100 patients who had undergone modified radical mastectomy from 1966 to 1975 for the purpose of comparing early and late complications. In each group, 80 patients were involved in long-term follow-up. Immediate postoperative complications—notably seromas, wound infection, and flap necrosis—were found to be considerably fewer following modified radical mastectomy. There was also a significantly lower incidence of late complications, such as limb edema and recurrent infection, after modified radical mastectomy. Since the cure rates achieved by the two radical mastectomy procedures appear to be similar, it is concluded that modified radical mastectomy is the procedure of choice in stages I and II cancer of the breast.
Résumé Nous avons relevé les dossiers de 100 patientes traitées par mammectomie radicale conventionelle et de 100 patientes traitées par mammectomie radicale modifiée et avons comparé les complications post-opératoires observées dans les 2 groupes. Toutes les patientes furent opérées entre 1966 et 1975. Dans chaque groupe, nous avions un recul suffisant chez 80 patientes pour évaluer les résultats à long terme. Les complications post-opératoires, immédiates (sérÔmes, infections de plaie, nécrose de greffe cutanée) ou tardives (lymphoedème du bras, infections à répétition), furent beaucoup plus rares après mammectomie radicale modifiée. Etant donné que les taux de guérison obtenus avec ces 2 opérations semblent Être les mÊmes, nous en concluons que la mammectomie radicale modifiée est l'opération de choix pour traiter les cancers du sein au stade I et II.
  相似文献   
118.
119.
Eight-year event-free survival (EFS) was evaluated in 205 patients with acute lymphoblastic leukemia (ALL), to consider the efficacy of high-dose methylprednisolone (HDMP) given during remission induction chemotherapy between 1 and 29 days. The St Jude Total XI Study protocol was used after some minor modifications in this trial. Patients were randomized into two groups. Group A (n = 108) received conventional dose (60 mg/m(2)/day orally) prednisolone and group B (n = 97) received HDMP (Prednol-L, 900-600 mg/m(2) orally) during remission induction chemotherapy. Complete remission was obtained in 95% of the 205 patients who were followed-up for 11 years; median follow-up was 72 months (range 60-129) and 8-year EFS rate was 60% overall (53% in group A, 66% in group B). The EFS rate of group B was significantly higher than of group A (P = 0.05). The 8-year EFS rate of groups A and B in the high-risk groups was 39% vs 63% (P = 0.002). When we compared 8-year EFS rate in groups A and B in the high-risk subgroup for both ages together /=10 years, it was 44% vs 74%, respectively. Among patients in the high-risk subgroup with a WBC count >/=50 x 10(9)/l, the 8-year EFS was 38% in group A vs58% in group B. During the 11-year follow-up period, a total of 64 relapses occurred in 205 patients. In group A relapses were higher (39%) than in group B (23%) (P = 0.05). These results suggest that HDMP during remission-induction chemotherapy improves the EFS rate significantly for high-risk patients in terms of the chances of cure.  相似文献   
120.
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