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1.
Release of cholecystokinin from rat cerebral cortex in vivo: role of GABA and glutamate receptor systems 总被引:1,自引:0,他引:1
Using cortical cups in chloralose-urethanized rats, the in vivo release of cholecystokinin-like immunoreactivity (CCK-LI) from cerebral cortex was examined. Resting levels of cholecystokinin-like immunoreactivity ranged from 20 to 30 pg/20 min sample. The addition of potassium (40 mM) in excess, resulted in a highly significant elevation in the levels of CCK-LI in the cortical superfusate. Deletion of calcium and the substitution of cobalt (10 mM), resulted in a significant reduction in both resting release and the release otherwise evoked by the addition of potassium. Focal electrical stimulation of the cortex (20 Hz), resulted in a significant (1.9 +/- 0.2-fold, n = 8) increase in the levels of CCK-LI. The addition of glutamate (10(-6)-10(-4) M) of kainic acid (10(-8)-10(-6) M), also resulted in significant elevations in the levels of CCK-LI. The co-administration of a putative glutamate receptor antagonist, kynurenic acid (10(-4) M) resulted in a significant reduction in the levels of release otherwise evoked by the addition of glutamate, but not by electrical stimulation. The addition of GABA (10(-5)-10(-3) M) resulted in a dose-dependent decrease in the resting release of CCK-LI, and the release evoked by glutamate. Picrotoxin (10(-6)-10(-4) M), resulted in a highly significant increase in the levels of CCK-LI in the cortical effluent. These results are consistent with a tonic GABAergic inhibition of CCK-releasing neurons. The treatment of the animal with diazepam (30 mg/kg, i.p.) also resulted in a significant reduction in resting release and the release otherwise evoked by focal cortical stimulation. 相似文献
2.
目的探讨三康胶囊对高原人体运动后一氧化氮(NO)及其合酶(NOS)、乳酸(BLA)、血氨(Ammo)的影响.方法选择进驻海拔3 700 m高原1年的10名健康青年,口服三康胶囊15 d,在服药前后分别采用功量自行车进行渐增负荷运动,测定其血清 NO、NOS、BLA及Ammo含量.结果服药后较服药前运动后NO水平[(101.02±6.49) Vs (77.10±8.11)]和NOS活性[(71.40±7.23) Vs (56.29±6.28)]均增高, BLA[(7.58±0.79)Vs (6.13±0.74)]和Ammo[(80.11±9.44)Vs (69.38±8.86)]降低,有非常显著性差异(P<0.01).结论 三康胶囊能增强高原移居者运动后NOS活性,加速乳酸清除,减缓运动疲劳的发生. 相似文献
3.
Susumu Ishikawa M.D. Akio Ohtaki M.D. Toru Takahashi M.D. Tetsuya Koyano M.D. Yutaka Hasegawa M.D. Satoshi Ohki M.D. Yukitaka Isa M.D. Kennichi Arai M.D. Fumio Kunimoto M.D. Yasuo Morishita M.D. 《Journal of cardiac surgery》1997,12(3):176-179
A bstract The purpose of this study was to assess the efficacy of nasal mask bi-level positive airway pressure (BiPAP) support in managing respiratory failure following cardiovascular surgery. A total of 20 patients requiring postoperative prolonged respiratory support of 72 hours or longer were studied. BiPAP support was used for eight patients (BiPAP group); the other 12 patients were managed using ordinary oxygen mask treatment (control group). The mean age of the BiPAP group and control group was 65 and 58 years of age, respectively. The mean period of postoperative endotracheal intubation of the BiPAP group and control group was 12 ± 5 days and 7 ± 1 days, respectively. Reintubation was necessary in two patients of the control group. The BiPAP group patients required no reintubation. BiPAP support was discontinued within 48 hours in 6 out of 8 patients. The respiratory rates of control group increased (p < 0.1) 24 hours after extubation, however, the respiratory rates of the BiPAP group remained unchanged. The values of the respiratory index of the BiPAP group improved significantly (p < 0.01) after BiPAP management (from 1.5 ± 0.2 to 0.9 ± 0.2). The values of the control group, however, remained unchanged. A-aDO2 and Qs/Qt decreased (p < 0.1) in the BiPAP group. There were no significant differences in central venous pressure or circulatory status between the two groups. In conclusion, BiPAP support is a noninvasive management technique for postoperative respiratory failure and may also prevent prolonged endotracheal intubation. 相似文献
4.
5.
Four adult ostriches developed sudden onset paresis and were unable to stand up when disturbed. After treatment with selenium and vitamin E, one of the birds could stand and move normally. The others died and post mortem examination revealed pale patches in the thigh muscles. Histopathological examination showed degeneration of skeletal muscles as seen in nutritional myopathy. Serum selenium and vitamin E levels were low whereas aspartate aminotransferase and creatine kinase levels were very high. All remaining birds on the farm were given multimineral and vitamin E supplement and no more cases were seen. 相似文献
6.
The aim of the present study was to examine whether ischaemic episodes of less than 5 min could induce preconditioning or stunning in the isolated rat heart. Hearts were subjected to total global ischaemia of 1, 2 and 4 min followed by 10 min of reperfusion before an 18-min main ischaemic period and 30 min of reperfusion. The effects on physiology, purine metabolism and anaerobic glycolysis were compared with a control group subjected to the main ischaemia only. The brief ischaemic episodes did not produce stunning based on the recovery of left ventricular developed pressure (LVDP) and heart rate (HR) product during the first reperfusion. Preconditioning of 11–14% increased recovery of LVDP x HR during the second reperfusion was observed in the 1- and 4-min group. In the 2-min group a low repayment of flow debt during the first reperfusion was associated with a slightly reduced recovery of LVDP x HR compared to the other preconditioned groups during the second reperfusion. Only in the 4-min group was preconditioning associated with fewer breakdown products of the purine nucleotide pool (adenosine) and anaerobic glycolysis (lactate) in both tissue and effluate after the main ischaemia. Preconditioning (reflected in recovery of function) could be produced with ischaemic episodes of less than 5 min that did not produce stunning. Thus, stunning is probably not the primary cause of preconditioning. 相似文献
7.
Anders Lundqvist Adiba Isa Thomas Tolfvenstam G?ran Kvist Kristina Broliden 《Journal of clinical virology》2005,33(1):71-74
BACKGROUND: Human parvovirus B19 (B19) polymerase chain reaction (PCR) is now a routine analysis and serves as a diagnostic marker as well as a complement or alternative to B19 serology. The clinical significance of a positive B19 DNA finding is however dependent on the type of tissue or body fluid analysed and of the immune status of the patient. OBJECTIVES: To analyse the clinical significance of B19 DNA positivity in bone marrow samples from rheumatic patients. STUDY DESIGN: Parvovirus B19 DNA was analysed in paired bone marrow and serum samples by nested PCR technique. Serum was also analysed for B19-specific IgG and IgM antibodies and the results were compared with clinical and epidemiological data. RESULTS AND CONCLUSIONS: B19 IgG was found in 41 of 50 patients (82%) whereas none was B19 IgM positive. The serologic evaluation showed that none of the patients had acute B19 infection. However, B19 DNA was detected by PCR in 13 of 50 (26%) bone marrow samples from these patients indicating a high frequency of persistent infection compared with previous reports of patient groups and healthy controls. In the study, 22 patients had rheumatoid arthritis (RA) and 7 of these RA patients were B19 DNA positive in bone marrow. Rheumatoid factor was positive in 4 of the 7 B19 DNA positive RA patients as compared with Rheumatoid factor positivity in all of the 15 B19 DNA negative RA patients. Erosive arthritis in X-ray was less common in the B19 DNA positive group than in the B19 DNA negative group. A high frequency of parvovirus B19 DNA was thus detected in bone marrow samples in rheumatic patients. The clinical data does not support a direct association between B19 PCR positivity and rheumatic disease manifestation. Therefore, the clinical significance of B19 DNA positivity in bone marrow samples from rheumatic patients must be interpreted with caution. 相似文献
8.
Shriwas SR Rahman Isa AB Reddy SC Mohammad M Mohammad WB Mazlan M 《The Medical journal of Malaysia》1996,51(4):447-452
Few attempts have been made to determine the risk factors for diabetic retinopathy which is a major cause of visual impairment and blindness. One hundred and forty patients of diabetes mellitus were studied to determine the prevalence and types of retinopathy, and its relation to various risk factors. Nearly half (48.6%) of the patients suffered from retinopathy. The significant associated risk factors were long duration of diabetes, proteinuria and elevated serum creatinine level. However, there was no significant association between the prevalence of retinopathy and high levels of serum cholesterol, C-peptide levels, associated hypertension, and glycaemic control of diabetes mellitus. An effective screening programme for detection of retinopathy in the patients of diabetes as a regular practice is encouraged. 相似文献
9.
Zainudin BM Roslina AM Fadilah SA Samad SA Sufarlan AW Isa MR 《The Medical journal of Malaysia》1996,51(1):136-140
Three cases of diffuse panbronchiolitis (DPB) occurring in two Malaysian Chinese patients and one Malay patient are reported. They had similar clinical, radiological and physiological features which are characteristic of DPB. The diagnosis in one of the cases was confirmed histologically by transbronchial lung biopsy. These could be the first three cases identified in Malaysia. 相似文献
10.
A survey of infant-feeding and weaning practices of 566 mothers, systematically sampled from 15 rural villages, randomly selected in the district of Tumpat, Kelantan was carried out. Almost all mothers (97.3%) breastfed their children, reinforcing the previously reported high incidence of breast-feeding among rural Malaysian mothers. One hundred and seventeen (21.3%) of the 551 children breastfed were also given mixed feeding with infant fomulae as well. Weaning started before 4 months of age in 28.3% of the children and after 6 months of age in 12.8% of the children. The 3 most common type of food used in weaning were Nestum (45.0%), rice porridge or paste (42.6%) and wheat porridge or cakes (11.5%). Forty eight children (12.1%) discontinued breastfeeding once weaning was initiated. The main reasons for initiating weaning was mothers' perception that there was insufficient milk and that the child was always hungry (55.7%). Most mothers were also given advice by the health clinic staff on weaning, including the timing and the suitable weaning foods to give. All of the mothers were able to name at least one commercial weaning food product available in their community. 相似文献