Arterial baroreflexes are the most important mechanism of cardiovascular system that can respond to rapid blood pressure changes during everyday activities. In this study we have assessed adaptive responses of carotid baroreflexes during isometric & dynamic exercise and compared the results with acute response during rest. The applied work loud in dynamic exercise was 100 watts and in isometric exercise it was 50% of calculated maximum force .Experiments were performed on 12 young male healthy sedentary volunteers aged between 21-28. This study was done in three exercises. In all three protoc1es, adaptation process during stimulation was assessed by studying of beat to beat R-R interval of ECG. In order to stimulate the carotid baroreceptors neck suction device Eckberg model was used and duration of stimulation was 10 seconds. ECG was taken carefully. Examination of adaptative process during stimulation showed maximal response achieved in resting state is statistically significant compared with that of isometric and dynamic exercise respectively (P<0.038, P<0.007). where as, comparison of adaptive response of rest state with isometric exercise and dynamic exercise was not statistically significant. There is no significant relation between maximal and adaptative response in dynamic and isometric exercises, although in general adaptative process in resting state compared with isometric and dynamic exercise was more pronounced. This observation confirmed that Vagal withdrawal with alimited degree of sympathic stimulation are challenged in this phenomenon. In other words the SA response to vagal stimulation is retarded by sympathic stimulation.      

Electrodiagnostic evaluation of radicular LBP is one of the valuable measures in detecting lumbosacral root lesion and it is comparable to CT-Myelography. This study were carried out on over 151 patients including 114 male and 37 female between 16 to 60 year old of age from August 1996 to August 1997 in Military Hospital No: 501 of Medical 5cience University for the Army of Islamic Republic of Iran. The study included nerve conduction studies and needle electromyography and following results obtained all sensory NC5 were Normal Amplitude of tibial and deep peroneal nerves were decreased in 4 and 9 cases, respectively. H-reflex was impaired in 33 patients. Needle electromyography studies recorded from L1 to 53 myotomes revealed33% involvement and involved roots in order of increasing frequency which were S3,S4<L3,L2<L4<51 <L5. Finally according to this study we recommend that increased insertional activities and early polyphasic motor units action potentia Is be regarded as root irritation and fibrillation potentials, positive sharp waves, long duration high amplitude and polyphasic motor unit action potentials as roots lesion.

Clinical, laboratory and radiographic data was studied from a 13 years old male Doberman dog with asymmetric ataxia, nystagmus, head tilt to right side, vomiting, falling and anorhexia. The absence of physical abnormalities of the tympanic membrane and absence of radiographic changes within the tympanic bulla or petrous temporal bone were the criteria used to make the diagnosis of “Geriatric canine vestibular disease”.

Considering the relatively high incidence of severe mitral stenosis in Iran, and for evaluation of the efficacy of PTMC in affected patients, this study was performed on referrals of Shaheed Modarres hospital from 1997 to 1999. The clinical trial and quasi-experimental strategy of this study was performed on 141 patients with signs of dyspnea and MS was diagnosed by echocilfdiography. The patients characteristics, severity of condition, accompanying disorders and valve state were recorded and evaluated. Left and right catheterism were performed for all of the patients and severity of mitral stenosis was classified according to Sellers' method and mitral valve gradient and hemodynamic parameters before and after PTMC were evaluated. For evaluation of aortic failure, aortography was performed and data were statistically analyzed. The age of patients was 37±10 and 82% of them were female and 18% were male. In addition, 26% of them had atrial fibrillation. The area of mitral valve increased from 0.98±0.2 to 1.71±0.2 cm2 (P<0.0001) and its gradient decreased from 16.5±5.5 to 2.7±1.9 (P<0.0001), systolic pressure of pulmonary artery decreased from 49.7±17.9 to 21.5±6.5 mmHg and left atrial pressure decreased from 28±6.6 to 14.4±4.2 mmHg (P<0.0001). In addition, Performing PTMC was successful in 89.5% of patients with MVA≥1.5 cm2 and in 98.5% of patients with gradients less than 6 mmHg. In this respect, all of the patients showed a clear clinical improvement. Cardiac tamponade occurred only in one patient and for one patient with severe mitral failure, an immediate emergency operation was performed. In addition, two of them had atrial fibrillation. There was also no thromboembolic complication and/or death. It is concluded that PTMC is an effective and safe method for the treatment of patients with mitral stenosis and is successful for patients with high pressures in pulmonary artery and accompanied mild to moderate mitral failure. It is recommended to evaluate the long-term consequences of PTMC in patients.

Introduction and aim: Microembolic signals (MES) are usually observed by transcranial Doppler technology in patients with mechanical heart valve. These MES are almost always asymptomatic. This Study was done to evaluate frequency of MES in middle cerebral artry in patients with prosthetic heart valve. Methods: This descriptive-study was carried out in 22 patients with prosthetic mitral valve (St jude).Prothrombine time, history of CVA and AF of the patients were evaluated and frequency of MES in middle cerebral artery was monitored for one hour.Results: 77% of the patients had shown MES. The mean frequency (MF) of MES in 2 patients who had suffered of stroke after valve replacement was 61 signals per hour (sph). The MF of MES in 20 other patients was 73 (sph). The MF of MES in 6 patients with INR> or=2.5 and 16 patients with INR < 2.5 were 143 and 51 (sph) respectively. In 13 patients with atrial fibrillation (mean INR 2.15) and 9 patients with sinusal rhythm (mean INR 2.40) MF or MES were 50 and 104 (sph) respectively.Conclusion: The MES in patients with mechanical heart valve are not fibrinous and frequency of these MES is not related to risk of stroke in these patients.