Background Constipation is a common complication after stroke, and the results investigated overseas showed the incidence was about 30% ～60%. The difference of results is so significant because the time investigated and the diagnosis criterion used are different. There are less relative report about risk factors of constipation and no report about the impact of constipation on pragnosis. The study is to investigate the incidence and risk factors of new-onset constipation after stroke in the patients with acute stroke and to evaluate the impact of new-onset constipation occurrence on the prognosis in the patients.Methods A prospective cohort study of new-onset constipation was performed to investigate 154 cases of acute stroke patients who were hospitalized from December 2003 to October 2004 in the department of neurology, the first Affiliated Hospital of Sun Yat-sen University. We recorded the demographics, medical history,stroke severity and medication used. National Institutes of Health Stroke Scale (NIHSS), Barthel Index (BI)and Modified Rankin Scale (MRS) were evaluated in the 1st week and 4th week after stroke to evaluate the neurological function and ability of an independent life. BI and MRS were recorded at the 12th week after stroke.Patients were then followed for the development of stroke, the event such as recurrence or death. Constipation was defined by Rome Ⅱ criteria.Results The incidence of new-onset constipation after stroke within 4 weeks was 55. 31%, and the highest risk was within seven days after onset of stroke. Cox regression showed that the incidence of constipation occurrence was strongly related to neurological functional status of patients in the 1st week assessed by BI and the transform of surrounding for defecation. In the 4th week and 12th week after stroke, the rates of poor prognosis in patients with constipation in middling state were both higher than patients without constipation, and the difference was statistically significant respectively(P ＜ 0. 01 ;P = 0. 012).Conclusions The new-onset constipation occurrence in acute stroke is very common and its main risk factor is functional status assessed by Barthel Index at the 1st week after onset and the transform of surrounding for defecation. The results indicate that the new-onset constipation occurrence after stroke has negative effects on the outcome of partial stroke patients.

Objective To study the relationship between MRI features and pathological characteristics of the renal clear cell carcinoma,and to conduct a comparative analysis.Methods 23 patients renal clear cell carcinoma who were proved by postoperative pathology were retrospectively analyzed. The preoperative MRI findings and the postoperative pathological characteristics were compared. Results MRI plain scan showed uniform signal was seen in 2 cases, and mixed signal was found in 21 cases with cystic and necrosis. Blood was seen in 11 cases and false envelope was present in 12 cases. Dynamic enhanced scanning revealed that solid part was enhanced obviously, it was lower than the renal cortex but higher than the renal medulla in cortical phase and continued to be enhanced in medullary phase and delay phase.Postoperative pathological characteristics showed that tumor profiles were yellow-white and cystic and necrotic structures were present within tumors, blood was found in 17 cases. Endoscopic tumor cells were present in solid nests or acinar structure, and mesenchyma was rich in thin-walled vessels involved in reticular interval.14 cases were found to have false envelope.Conclusion Renal clear carcinoma MRI imaging manifestion is related to organixational srructure. MR plain scan combined with dynamic enhanced scan has very high value in the diangnodis of renal cell carcoinoma.

AIM:To study the effect of hypertensive arteriosclerosis on cerebral blood flow autoregulation (CBFA), and to introduce a new method to measure the lower limit. METHODS:The blood velocities and blood pressure was recorded simultaneously and the curves of CBFA were analyzed and classified into classical and non-classical pattern. The lower limit were determined by clinical closing pressure (CCP) and the curve CBFA. RESULTS:When the blood pressure was decreasing, the classical and non-classical pattern of the cerebral blood flow autoregulation were 25% and 75% respectively in normal SD rats, while they were 40.55% and 54.45% respectively in renovascular hypertensive rats (RHR). However, when the blood pressure was elevating, the classical and non-classical pattern were 76.47% and 23.53% respectively in SD rats, while they were all classical in RHR. Furthermore, in SD and RHR ras, the lower limits measured by CCP were well in accordance with that measured by CBFA. CONCLUSION:Hypertensive arteriosclerosis could influence the limits and the patterns of cerebral blood flow autoregulation. The lower limit of CBFA can be measured and analyzed by CCP.

Objective To evaluate the diagnostic value of cardiac magnetic resonance (CMR) in suspected coronary heart disease patients with electrocardiogram abnormalities but normal coronary angiography. Methods The data of 25 suspected coronary heart disease patients with electrocardiogram abnormalities but normal coronary angiography were collected from Taiyuan central hospital between October 2010 and April 2012. Comparison was done in terms of anterior interventricular septal thickness, left ventricular posterior wall thickness, left ventricular end diastolic dimension, left ventricular end systolic dimension, left atrial diameterand ejection fraction measured by CMR and by UCG. Correlation of the aboved paremeters between the 2 imaging exams. Results 40%of patients had their diagnosis changed after CMR exam, 32%of the patients with adjusted assessment. The differences in anterior interventricular septal thickness, left ventricular posterior wall thickness, left ventricular enddiastolic dimension, left ventricular end systolic dimension, left atrial diameter, ejection fraction by CMR and by UCG were similar (P>0.05) with positive correlation (P<0.01). Conclusions CMR can provide diagnosis and evaluation information to chest pain patients with ECG abnormalities but normal CAG, and it is a good supplement for routine examination.

ObjectiveTo investigate the correlation of dysphagia and malnutrition of patients with acute stroke and to establish intervention countermeasures.MethodsThe Swallow Water Test was performed by professional rehabilitation nurses in 100 cases of acute stroke patients without food and water within 24 hours after admission and two weeks later to confirm the existence of dysphagia.Rehabilitation exercises of swallow function were performed pertinently.At the same time,we evaluate the state of nutrition of these patients and followed up for two weeks,and to determine the state of malnutrition.ResultsThere was 23.0%(23/100) acute stroke patients didn't pass the initial Swallow Water Test,19 patients (82.5%) with dysphagia could swallow normally before discharge,13% patients needed indwelling nasal-gastric tube.The rate of malnutrition in dysphagia group (34.8%) was higher than patients without dysphagia (11.7%),the difference was statistically significant (P<0.05).In addition,the activity ability of daily living was poorer,the disability degree was higher and the average day of hospitalization was longer in dysphagia group in the fourth week.ConclusionsTo estimate the dysphagia timely in acute stroke patients can make the medical staff think highly of this status to formulate the scientific project of nutrition and provide the scientific rehabilitation exercises to the patients.It can decrease the incidence rate of malnutrition,complications and the disability degree of the acute stroke patients and to promote early rehabilitation.

Objective 　To establish a new practical method to assess the cerebral blood flow autoregulation. Methods　We assessed the flow velociey of middle cerebral artery with transcranial Doppler and recorded invasively the blood presure simultaneonsly. Then on the basis of critical closing pressure (CCP), the lower limit of cerebral blood flow autoregulation and the blood flow resistance of arterioles were calculated.The data compared with the results generated by routine method. Results　The lower limit of autoregulation working out by CCP was 70.88±24.05 mmHg, which was similar to the result measured by routine method. The lower limit of autoregulation and the arteriole resistance in RHR were significantly higher than those of normal controls, and highly relate to arterial blood pressure significantly, especially pulse pressure. Conclusions　The physiology and pathology of cerebral blood flow can be evaluated conveniently and accurately by assessment of the lower limit of autoregulation and arterioles resistance with CCP.

Objective To compare the dosimetric difference between jaw tracking technique (JTT) and static jaw technique (SJT) in dynamic intensity-modulated radiotherapy (IMRT) for preoperative radiotherapy of rectal cancer patients.Methods Jaw tracking and static jaw were used to develope the intensity-modulated plans for 10 patients respectively.For all the patients,the dose to surrounding tissues was minimized as low as possible,the 95％ volume of the planning target volume (PTV) and planning gross target volume (PGTV) satisfy the prescribed dose.The doses of the planning target volumes,organs at risk and normal tissue were detected by dose-volume histogram.Two groups of treatment plan dose were verified by ionization chamber array 2D-Array 729 and OCTAVIUS (PTW) phantom.Results The treatment plans of two groups could satisfy the clinical requirements.There was no significant difference between the maximum and the mean dose of target.The volumes of jaw tracking dynamic intensity-modulated radiotherapy were lower,including the V5,V10,V20,V30,V40 (volumes receiving 5,10,20,30 and 40 Gy,respectively),mean dose(D) for body and V10,V20,V30,D for bilateral femoral head,bladder,and small intestine.There was significant difference for the results (t =-2.32-12.24,P ＜0.05).The verification results showed that the treatment plans were all passed the dosimetric verification.Conclusions Jaw tracking intensity-modulated radiotherapy and jaw fixed IMRT plan could achieve equal dose coverage in patients with rectal cancer,while jaw tracking techniques could reduce normal tissue dose and organs at risk dose.

AIM: To study the effect of hypertensive arteriosclerosis on cerebral blood flow autoregulation (CBFA), and to introduce a new method to measure the lower limit. METHODS: The blood velocities and blood pressure was recorded simultaneously and the curves of CBFA were analyzed and classified into classical and non-classical pattern. The lower limit were determined by clinical closing pressure (CCP) and the curve CBFA. RESULTS: When the blood pressure was decreasing, the classical and non-classical pattern of the cerebral blood flow autoregulation were 25% and 75% respectively in normal SD rats, while they were 40.55% and 54.45% respectively in renovascular hypertensive rats (RHR). However, when the blood pressure was elevating, the classical and non-classical pattern were 76.47% and 23.53% respectively in SD rats, while they were all classical in RHR. Furthermore, in SD and RHR ras, the lower limits measured by CCP were well in accordance with that measured by CBFA. CONCLUSION: Hypertensive arteriosclerosis could influence the limits and the patterns of cerebral blood flow autoregulation. The lower limit of CBFA can be measured and analyzed by CCP.

Objective To find the best model parameters through Monte Carlo simulation of 6 MV flattening-filter-free (FFF) beams in TrueBeam accelerator, and establish the foundation for the further study of the clinical dosimetry on 6 MV FFF X-rays.Methods Using the BEAMnrc and DOSXYZnrc codes, the percentage depth dose (PDD) and the off-axis ratio (OAR) curves of field ranges from 4 cm ×4 cm to 40 cm × 40 cm were simulated for 6 MV FFF X-ray by adjusting the incident beam energy, radial intensity distribution and angular spread, respectively.The simulation results and measured data were compared, where the optimal Monte Carlo model input parameters were acquired.Results The simulation was most comparable to the measurement when the incident electron energy, full width at half maximum (FWHM) and the spread angle were set as 6.1 MeV, 0.75 mm and 0.9°, respectively.The deviation of 1 mm (position)/1％ (local dose) could be met by the PDD of all tested field sizes and by the OAR when the fields sizes were no larger than 30 cm ×30 cm.The OAR of 40 cm ×40 cm field sizes fulfilled criteria of 1 mm (position)/1.5％ (local dose).Conclusions Monte Carlo simulation agrees well with the measurement and the proposed model parameters, which can be used for further clinical dosimetry studies of 6 MV FFF X-rays.

Purpose To summarized the methods for establishment, characteristics of vascular lesions in brain and heart and the application of stroke-prone renovascular hypertensive rats (RHRSP).Data sources and methods Most published original articles about RHRSP in our laboratory were reviewed.Results After the renal arteries were constricted bilaterally with ring-shape silver clips, the stroke-prone renovascular hypertensive rats were established. Hypertension was produced in all RHRSP (100%). The peak of blood pressure in RHRSP reached 29.1±3.0 kPa. The lesions of cerebral arteries and arterioles and the damage of cerebral capillary structure by hypertension were observed in the RHRSP. The incidence of spontaneous stroke was 56.4% within 40 weeks after the renal artery constriction. Left ventricular hypertrophy and small coronary arterial lesions in myocardium were discovered in all RHRSP. Myocardial infarction occurred spontaneously in 41.8% of RHRSP. The animal models have been used for the studies on mechanisms of stroke and myocardial infarction.Conclusions Because the vascular lesions in cerebrum and heart in RHRSP are similar to that in human beings with hypertension, RHRSP can be used in the studies on mechanisms of hypertensive arteriosclerotic stroke and cardiac lesions and on verifying the effects of different medications to complications of hypertension, and the results might be more reliable than that in animal models without hypertension.