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1.
Previous studies have described a pattern of complex behavior that occurs in the marine mollusc Aplysia during egg laying. Egg laying and the behavior are initiated by a burst of impulse activity in the neuroendocrine bag cells of the abdominal ganglion or by injection of bag cell extract. To more precisely identify the factors responsible for inducing the behavior we injected animals with egg laying hormone (ELH), one of the neuropeptides secreted by the bag cells. We found that ELH causes a behavior pattern similar to what occurs during spontaneous egg laying. This includes a temporal pattern of head movements consisting of waves and undulations, followed near the beginning of egg deposition by a transition to head weaves and tamps and inhibition of locomotion. There was also a small decrease in respiratory pumping. Except for respiratory pumping, a similar pattern occurred in a second group of animals injected with atrial gland homogenate, which is presumed to induce bag cell activity, but not in controls. These results further implicate ELH in regulation of the behavior. We discuss possible sites of action of ELH and the neural mechanisms by which the behavior is controlled.  相似文献   

2.
We describe a new method for determining the biological activity of heparin in plasma with use of thrombin and the substrate Tos-Gly-Pro-Arg-pNA. The procedure is based on the photometric determination of the inactivation of thrombin after incubation with plasma in the presence of endogenous antithrombin III (At III). The method allows the specific determination of heparin concentrations from 0.02 USP to 0.8 USP/ml of plasma in the presence of normal At III levels. It has been carried out manually by use of an Eppendorf spectrum line photometer or automatically by use of a Vitatron Akes analyzer. For evaluation, the results were compared with two standard samples which contained heparin in the low and high therapeutic range, respectively.  相似文献   

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Acinetobacter baumannii strain A148, a clinical isolate resistant to imipenem (MIC = 32 mg l-1), synthesized two beta-lactamases with pIs 6.3 and > 9.2. The pI 6.3 enzyme hydrolyzed the penicillins, including isoxazoylpenicillins, first-, second- and, to a lesser extent, third-generation cephalosporins. It was inhibited by chloride ions and by the penem beta-lactamase inhibitor BRL 42715. Clavulanate was a weak inhibitor and EDTA did not affect the beta-lactamase activity. This enzyme also hydrolyzed imipenem with a catalytic efficiency (Kcat/Km) of 1500 mM-1 s-1. Moreover, this purified beta-lactamase produced a positive microbiological clover-leaf test with imipenem. Therefore, the pI 6.3 beta-lactamase was considered to be involved in the imipenem resistance of A. baumannii strain A148.  相似文献   

5.
Although several new anticoagulant drugs are in development, heparin remains the drug of choice for most anticoagulation needs. The clinical effects of heparin are meritorious, but side effects do exist. Important untoward effects of heparin therapy including heparin-induced thrombocytopenia, heparin-associated osteoporosis, eosinophilia, skin reactions, allergic reactions other than thrombocytopenia and alopecia will be discussed in this article.  相似文献   

6.
Raises concern over a perceived bias toward diagnosing brain damage when test performance can be accounted for by nonneurologic factors. Psychologic conditions are identified that can impact neurophysiological test performance. Evaluation of consistency of performance and symptom validity testing are discussed as methods of detecting nonneurologic effects on test performance. Indexing of performance to trauma severity is recommended. Suggestions are made for future research on differentiating psychologic from neurologic patterns of neurophysiological performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

7.
Progress in pathology is related to application of new biological techniques and impact of electronic devices affecting transfer of information and images. The increase of specification of all kinds of disease classification induces a specific need for data exchange and expert consultation. The momentary technical situation in communication lines connected with medical fields, especially pathology is characterized by parallel operation of two basically different communication systems, namely a) systems based upon computerized data exchange (E-mail, etc.), and b) systems working at public access, i.e. telephone lines and their successors (digitized network, satellite system). Practical use in telecommunication in pathology has been gathered nearly exclusively by use of the second (public) system, and includes intraoperative classification of histological images (frozen sections), expert consultations, panel discussions, quantitative measurements, and access to image data bank systems. The use of remote control microscopes has been reported to work without major errors from Norway and Switzerland. In Norway, images and diagnostic informations are transferred by use of broad band networks (satellite communication), whereas in Switzerland the digitized network ISDN is used. The experiences show clearly that remote control microscopes are practicable and reliable tools for daily diagnostic work of pathologists, and that the quality of the transferred images is sufficient to allow sophisticated diagnoses. Expert consultations are routinely performed by use of the common telephone network in lung pathology, and can not be underestimated in their impact on the daily work. Accuracy of diagnosis, quality of staining and tissue handling, and reliability of diagnosis are automatically improved besides the positive legal aspects.  相似文献   

8.
The diagnosis of heparin-induced thrombocytopenia (HIT) may be affirmed by demonstrating heparin-dependent anti-platelet antibodies using the 14C-serotonin release assay (SRA). In this study, results of the SRA was compared with the recently described platelet factor 4 (PF4)/heparin enzyme-linked immunosorbent assay (ELISA). Compared with the SRA, the sensitivity and specificity of a PF4/heparin ELISA was 87% and 92%, respectively, using an assay developed in our laboratory; and 90% and 98%, respectively, using a commercially developed kit (Diagnostica Stago, Asnieres, France). However, antibodies to PF4/heparin were also detected in up to 8% of patients whose plasma was negative by SRA, and 23% of patients receiving heparin who were not thrombocytopenic. These data indicate that results obtained with the PF4/heparin ELISA and the SRA are generally in accord in patients with a clinical diagnosis of HIT. However, discrepant results occur in approximately 20% of cases because of the greater sensitivity of ELISA and the possible involvement of other heparin-binding proteins. The fact that each assay contributes independent information in some cases must be considered in the sequence of test performance and in providing consultation to the practicing hematologist.  相似文献   

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The relationship between plasma phenobarbital concentrations and anticonvulsant activity was determined against seizures induced in epileptic chickens by intermittent photic stimulation (IPS). Intraperitoneally administered phenobarbital produced a plasma-concentration-dependent reduction in both the incidence and severity of seizures. Complete protection against IPS-induced seizures was observed for a period of 6 h after acute phenobarbital administration during which the mean plasma phenobarbital concentrations were between 16.2 +/- 0.91 and 13.6 +/- 1.0 microgram/lm. Plasma phenobarbital concentrations below 3.6 +/- 0.06 microgram/ml had no measurable effect.  相似文献   

11.
A fetus with absent radii in both forearms was discovered on routine ultrasound examination performed at 18 weeks of pregnancy. No other significant abnormalities were found, and no signs of haemorrhage were detected. Serial ultrasound examinations revealed no evidence of fetal internal bleeding. At 37 weeks of pregnancy, a CBC obtained by cordocentesis under ultrasound guidance confirmed the diagnosis of thrombocytopenia absent radii (TAR) syndrome. Apheresis platelets were transfused into the umbilical vein to correct the thrombocytopenia and was followed by an uncomplicated delivery. No bleeding was encountered during the remainder of the baby's neonatal course. We conclude that TAR syndrome can be readily identified prenatally on sonogram, and if severe thrombocytopenia is confirmed by cordocentesis, platelets should be transfused to diminish the risk of serious internal bleeding during and immediately after delivery.  相似文献   

12.
Pathomechanism of thrombocytopenia and anaemia which frequently occur in patients with malaria is of a complex origin. Anaemia occurs due to sequestrating, destruction and hemolysis of damaged, parasite infected erythrocytes, as well as of the impaired and ineffective erythropoiesis in the marrow. Thrombocytopenia in these patients may also result from both increased destruction of blood platelets and decreased thrombocytopoiesis. Similar natures of the processes cause that anaemia and thrombocytopenia frequently co-exist in patients with malaria.  相似文献   

13.
Based on 109 blood samples taken from 36 dogs suffering from thrombocytopenia resonance thrombography with the resonance thrombograph RTG 801 (von Hoerner und Sulger Electronic GmbH, Schwetzingen; manufacturer: Fresenius AG, Bad Homburg) was distinctly more sensitive and more closely correlated to the platelet count using an optimized parameter of the resonance thrombogramm (RTG) in comparison to usual parameters. Nevertheless, clinical requirements regarding samples with platelet counts > 25,000/microliter were not fulfilled. Out of 13 samples with reduced platelet count and simultanous extended capillary bleeding time, depending on the used parameter a maximum of 9 samples could be detected as pathological by the RTG. The normal RTG in part of the cases with clearly altered primary haemostasis contrasts to the exclusive use of RTG in the screening of thrombocytopenia in dogs.  相似文献   

14.
Food allergy is a group of distinct clinico-pathological entities that have an immunological basis in common, and in which an abnormal or exaggerated immunological response to a specific food leads to disease. Some clinical pictures involving multiple organ system (anaphylaxis) are potentially fatal. The data on the incidence, prevalence, mortality rate and food products involved in food-induced anaphylaxis and the evolution of food sensitization compared with changes in eating habits are not very reliable. In the present study we analysed, over a period of 9 years (1984-1992), a group of 580 patients with pathological reactions to foods, 60 of which presented severe, near-fatal reactions. We sought the etiologic components and food sensitization in comparison with the principal tendencies of food consumption in France. Food products most frequently incriminated in anaphylactic reactions are not of a primary nutritional importance: celery (30%), crustaceans (17%), fish (13%), peanuts (12%), mango (6%), mustard (3%), but they are often hidden allergens in commercial foods. The sensitization to food products in the group of 580 patients reveals, in decreasing order of frequency: wheat (39%), peanuts (37%), crab (34%), celery (30%), soy (30%). Compared with previous data, the frequency of sensitization to different foods has changed; for instance, the sensitizations to wheat, soy, peanuts, celery, mustard, rice, are definitely increasing. The increased consumption and more attentive clinical research may be the reasons for this evolution. For products such as egg and pork, the data are stable and parallel with consumption, whilst for other products like milk and other dairy products, the increased consumption is accompanied by a decrease of the incidence of sensitization. The reactivity to some allergens may be affected by the way of preparing the food.  相似文献   

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Reports results of 2 experiments which show that, contrary to an operant hypothesis of depression, mildly or moderately depressed college students who increased their participation in events they had rated as pleasurable did not become less depressed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
In a study of plasma somatomedin activity in childhood scoliosis a group of five patients with congenital scoliosis was found to have significantly lower plasma somatomedin levels compared with a group of 20 normal children. A group of 52 patients with "idiopathic" scoliosis had normal plasma somatomedin levels. There is no apparent difference in the plasma somatomedin activity between the sexes, and no change in plasma somatomedin activity with chronologic age in these children, suggesting that normal adult somatomedin levels have been reached.  相似文献   

18.
BACKGROUND: Smoking regulations at the workplace have been found to be acceptable and effective in many studies conducted in the United States. There is limited knowledge, however, on acceptance and effects of smoking regulations in European countries, particularly among blue collar employees. METHODS: We conducted a survey on smoking behaviour and attitude toward smoking regulations and passive smoking in a South German metal company. A self-administered questionnaire was mailed to 1,500 predominantly blue collar employees of whom 974 participated in the study (response rate 64.9%). RESULTS: About 30% of the employees were not allowed to smoke at their immediate work area. Among them, about 95% of both smokers and nonsmokers agreed with this smoking policy. More than 60% of nonsmoking blue collar workers were bothered by passive smoking at work whether or not smoking was allowed at their immediate work area. In contrast, the proportion of nonsmoking white collar employees who were bothered by passive smoking varied from 52% if smoking was allowed at their immediate work area to 18% if smoking was not allowed. Prevalence of active smoking and average amount of smoking among active smokers were considerably lower among employees who were not allowed to smoke at work than among other employees. These differences were partly due to confounding by occupation, however, which was strongly related to both smoking habits and smoking policy. CONCLUSIONS: Our results, which confirm and extend previous findings, give further support to the acceptability and potential effectiveness of smoking regulations at the workplace. Particular efforts should be devoted to limit both active and passive smoking among blue collar employees.  相似文献   

19.
Low molecular weight heparins are used extensively for thromboprophylaxis. The aim of this study was to compare the activity of the low molecular weight heparin, enoxaparin, 20 mg and 40 mg, given once per day with unfractionated heparin, 7500iu given twice per day, in terms of their anti-Xa activity in puerperal women following caesarean section and with an additional risk factor for venous thromboembolism. Seventeen women were randomised to receive one of the three treatments. The anti-Xa activity associated with each treatment was measured prior to treatment and at 2, 4, 6, 12 and 24 hours. The mean anti-Xa values of the groups receiving enoxaparin, 20 mg and 40 mg, were significantly higher than those of the group receiving unfractionated heparin. There was no difference between the two enoxaparin groups in terms of the anti-Xa activity profiles. This study suggests that the use of enoxaparin is superior to unfractionated heparin in terms of anti-Xa activity.  相似文献   

20.
4 g% aqueous solutions of heparin were irradiated with the gamma radiation doses of 4.6 x 10(5) or 9.2 x 10(5) rads. The irradiated and also the non-irradiated heparin samples were fractionated using a Sephadex G-200 column. With radiation, the peak of the molecular weight distribution curves shifted toward the lower molecular weight. Also, the number average molecular weight decreased by 8.2 and 11.5% with the doses of 4.6 x 10(5) and 9.2 x 10(5) rads, respectively. The anticoagulant activity depended on the molecular weight of the heparin fractions. For the heparin fractions with molecular weights below 7,900, the anticoagulant activity decreased with radiation. Thus, for a heparin fraction with a molecular weight of 6,200, the anticoagulant activity decreased from 211 to 198 IU/mg after 4 h of irradiation.  相似文献   

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