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141.
Da-Nian Zhu, Long-Mei Xue, Peng Li. Effect of central muscarine receptor blockade. with DKJ-21 on the blood pressure and heart rote in stress-induced hypertensive rats.
The experiments were performed on Wistar or Sprague-Dawley rats of both sexes divided at random into stress and control groups. The rats in the stress groups were put into cages and subjected to electric foot-shocks and noises for 9-15 days, which caused an increase in blood pressure (BP) and heart rate (HR). In hypertensive rats DKJ-21 (4mg/lml) was injected intravenously (i.v.), and 0.5-1.0h after administration the BP and HR dropped from the high level to normotensive level. In normotensive rats, however, administration of DKJ-21 had no effect on BP or HR. In separate groups of normotensive rats, pretreatment of DKJ-21 (4 mg/l ml, i.v.) blocked the pressor and tachycardiac effect induced by microinjection of physostigmine (0.4μg/0.1 /μl/site), corticosterone (40μg/0.1μl/site) or aldosterone (40 μg/0.1 μl/site) into the rostral ventrolateral medulla (rVLM). Furthermore, DKJ-21 also attenuated the enhancement of the pressor response to stimulation of the defense area in the midbrain, which was induced by microinjection of drugs (mentioned above) into the rVLM. These results indicate that i.v. DKJ-21 can selectively block the muscarinic receptors in the rVLM in stress-induced hypertensive rats, which suggests that abnormal enhancement of cholinergic mechanism in the rVLM may be related to hypertensive effects of corticoids in this area. 相似文献
The experiments were performed on Wistar or Sprague-Dawley rats of both sexes divided at random into stress and control groups. The rats in the stress groups were put into cages and subjected to electric foot-shocks and noises for 9-15 days, which caused an increase in blood pressure (BP) and heart rate (HR). In hypertensive rats DKJ-21 (4mg/lml) was injected intravenously (i.v.), and 0.5-1.0h after administration the BP and HR dropped from the high level to normotensive level. In normotensive rats, however, administration of DKJ-21 had no effect on BP or HR. In separate groups of normotensive rats, pretreatment of DKJ-21 (4 mg/l ml, i.v.) blocked the pressor and tachycardiac effect induced by microinjection of physostigmine (0.4μg/0.1 /μl/site), corticosterone (40μg/0.1μl/site) or aldosterone (40 μg/0.1 μl/site) into the rostral ventrolateral medulla (rVLM). Furthermore, DKJ-21 also attenuated the enhancement of the pressor response to stimulation of the defense area in the midbrain, which was induced by microinjection of drugs (mentioned above) into the rVLM. These results indicate that i.v. DKJ-21 can selectively block the muscarinic receptors in the rVLM in stress-induced hypertensive rats, which suggests that abnormal enhancement of cholinergic mechanism in the rVLM may be related to hypertensive effects of corticoids in this area. 相似文献
142.
本文对20岁以上22830人按HBsAg状况和肝损害表现分队列进行随访,平均追踪6.8年,在肝癌高发区和低发区均以HBsAg携带者并有重度肝损害者(肝大+肝功能异常)的肝癌死亡率和相对危险性最高,相对危险性分别为37.3和22.5倍。以无肝大和肝功能异常的非携带者最低,肝癌的发生和肝损害的程度呈平行关系。HBsAg携带者发生肝癌死亡的相对危险性高于非携带者7倍,并发现HBsAg携带并有重度肝损害的肝癌死亡的平均年龄显著提前。认为肝癌高发区人群中HBV的持续感染和肝损害的广泛存在是导致肝癌高发和早发的重要因素。 相似文献
143.
This study was conducted to determine the occurrence of menstrual-linked asthma (MLA) in India in 100 consecutive female asthmatics in the reproductive age group. The patients were required to respond to a questionnaire concerning the relationship between their asthma and the menstrual cycle. Twenty-three patients had subjective perception of deterioration in symptoms of asthma in relation to the menstrual cycle. Ten patients from both groups were also required to maintain a daily peak expiratory flow rate (PEFR) diary for 2 consecutive menstrual cycles. The mean total duration of illness in patients with MLA was significantly longer than in patients without cyclic exacerbation. Cough and breathlessness were also significantly more severe as was the disease. This was evidenced by the more frequent emergency room visits and hospitalizations in these patients. Menstrual-linked worsening of asthma was most common in the premenstrual week (17 patients). In 8 of these 17 patients, this phenomenon continued to occur during the menstrual week also. Interestingly, 1 patient complained of deterioration of asthma 2 days after menstruation was over. Such an observation is yet to be recorded. Fourteen patients reported an increase in symptoms with almost every cycle while 3 had worsening related to specific season only. Sixteen patients often required extra medication during the premenstrual and/or menstrual weeks. A significant association was also observed between severity of premenstrual syndrome and MLA. The mean PEFR values over 2 cycles revealed a significant fall in the morning as well as evening values in the premenstrual and menstrual weeks as compared to the midcycle week in patients with MLA. This fall was maximal in the premenstrual week. Such a fall was not observed in asthmatics without menstrual exacerbation of symptoms. MLA was detected in about a fourth of the female asthmatics in India and it appears to represent a more severe form of the disease. This study also documented that MLA was associated with an increase in airway resistance and was not simply due to an increased perception of symptoms during the premenstrual or menstrual weeks. 相似文献
144.
145.
T. Rechlin 《Intensive care medicine》1995,21(7):598-601
Objective Since intoxication with tricyclic antidepressants is common, a supplementary screening method for differentiation between therapeutic and supratherapeutic ranges would be a valuable diagnositc tool, particularly in delirious and unconscious patientsSetting 109 patients treated with amitriptyline, 8 patients treated with doxepin, 10 patients treated with clozapine, and 72 normal control subjects matched for age and sex were tested for heart rate variability while resting.Results Considering time and frequency derived measures, which are rather independent of heart rate, the patients showed significantly decreased heart rate variability parameters (p<0.0001), as compared with the normal subjects. Of the patients presenting delirious symptoms 6 showed coefficients of variation more than 4 standard deviations below the mean control value.Conclusions As heart rate variability can be easily calculated, this measurement is suggested as a useful tool to quickly exclude or support the diagnosis of chronic intoxication with tricyclic antidepressants or clozapine. 相似文献
146.
Fear and the startle reflex: Blink modulation and autonomic response patterns in animal and mutilation fearful subjects 总被引:7,自引:1,他引:6
The present study was designed to examine the pattern of startle reflex modulation and autonomic responses for individuals high in animal or blood-injury fear when viewing pictures of their feared objects. Sixteen individuals in each fear group and 16 low-fear control individuals viewed 32 color slides depicting fear-relevant, unpleasant but fear-unrelated, neutral, and pleasant scenes. Free viewing times were assessed in a second phase of the procedure as an index of avoidance behavior. Exposure to pictures of feared objects resulted in a consistent startle reflex potentiation and behavioral avoidance in both fear groups. This activation of the basic aversive system was independent of the autonomic pattern of the fear responses, which differed for the high-fear groups. These results suggest that the probe startle response indexes the organism's basic motivational disposition and add new information to the assessment of fear. 相似文献
147.
P. K. Lommatzsch I. H. Kirsch 《Documenta ophthalmologica. Advances in ophthalmology》1988,68(3-4):225-238
Therapeutic results are presented with follow-up examinations of at least 5 years (min. 5 years, max. 22 years) after 106Ru/106Rh plaque radiotherapy of posterior uveal melanomas. Out of 227 patients 146 (= 64.3%) could be treated successfully, 37 (= 16.3%) had to be enucleated and are alive, 44 (= 19.4%) died from metastases and 40 (17.6%) from other causes. 75.0% of all small melanomas (T1a) showed an excellent regression pattern to flat scars. Five years after treatment the survival rate was 83.7% (deaths from any causes) respectively 88.2% (deaths from metastases only) and 64.8% (deaths from any causes) respectively 79.7% (deaths from metastases only) ten years after irradiation. 106Ru/106Rh plaque radiotherapy can be recommended for small (Tla, b) and medium sized (T2) choroidal melanomas. 相似文献
148.
Milena G. J. Jahoda Helen Brandenburg Titia Cohen-Overbeek Frans J. Los Eva S. Sachs Juriy W. Wladimiroff 《American journal of medical genetics. Part A》1993,46(5):483-485
Data from 4,300 consecutive cases following prenatal diagnosis by transcervical (TC) CVS (n = (1,570) and transabdominal (TA) CVS (n = 2,370) were evaluated. In the follow-up study only infants examined by a physician were included. Gestational age varied between 8.5 and 11.6 weeks (mean 10.3 weeks) for TC-CVS and between 9.3 and 20 weeks (mean 12.3 weeks) for TA-CVS 98% of TC-CVS was performed at 9–10 weeks, 80.7% of TA-CVS procedures were carried out at 12–15 weeks. Selective termination took place in 97 cases of TC-CVS (6.1%) and in 72 cases of TA-CVS (2.6%). Another 8 Women had a termination for psychosocial reasons, resulting in 4,123 (1,469 TC, 2,645 TA) continuing pregnancies. The overall fetal loss rare <28 weeks was 5.4% (n = 80) for TC-CVS and 2.6% (n = 70) for TA-CVS. The overall incidence of congenital abnormalities after birth was 0.9%. Two terminal transversal limb defects were detected in the TC-CVS group (0.14%) against one (0.04%) in the TA-CVS group. © 1993 Wiley-Liss, Inc. 相似文献
149.
Purpose. Flexible parametric models describing the input process after extravascular drug administration are needed for the assessment of absorption rate and the use of population methods in bioavailability and bioequivalence studies.
Methods. The oral concentration-time curve modeled as the product of the input and disposition function in the Laplace domain was obtained by numerical inversion methods for parameter estimation. The utility of the inverse Gaussian input density was examined using bioavailability data of an extended-release dosage form. Measures of rate of absorption and the cumulative absorbed amount profile were defined in terms of the estimated model parameters.
Results. Accurate estimation of absorption parameters was achieved by simultaneous fitting of the extravascular and intravascular data (describing the latter by a triexponential function). The new input function allowed a direct estimation of both extent of absorption and mean absorption time.
Conclusions. The findings suggest that the inverse Gaussian density is a useful input function. Its flexibility may reduce the effect of model misspecification in parameter estimation. All parameters can be readily interpreted in terms of the absorption process. 相似文献
150.
A群脑膜炎多糖菌苗接种前后流脑流行规律的改变及今后预防对策 总被引:1,自引:0,他引:1
Wu Gueikuens et al. Collaboration of Provincial Sanitary Anti-epidemic Station Institute of Epidemiology Microbiology 《中国公共卫生学报》1994,13(5):263-264
本文研究了在使用菌苗预防前后的流行性脑脊髓膜炎流行强度的变迁,年龄、地区及季节分布特点,人群的易感性及带菌率之间的关系,并讨论了今后的预防措施。 相似文献