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Objective To study the changes of nitric oxide (NO) concentration in arterial-capillary-venous vessels and the dynamic regulation mechanism of NO on the vessels during ventilation changes. Method The pulmonary vascular network model was established by using the COMSOL Multiphysics software, the dynamic regulation of NO on blood vessels was introduced, the flow-multiphysics coupling simulation was conducted to explore the effect of oxygen and blood flow on NO concentration and its distribution in pulmonary vascular network, and the dynamic regulation of NO on pulmonary vascular function in the case of ventilation lacking. Results Oxygen concentration and blood flow would jointly affect the NO distribution in the pulmonary vascular network. When lung ventilation was insufficient, the amount of oxygen entering the pulmonary capillaries decreased, and the NO concentration in pulmonary vein walls under static conditions was significantly reduced. The reduction of NO concentration under dynamic conditions led to vasoconstriction and decrease of blood vessel radius, resulting a dynamic compensation. Regulation of vascular tension regulation coefficient α would directly affect the regulation of NO. When α worked within a certain range, a higher value of α meant a larger change in vascular radius and a smaller change in NO concentration, and its effective value was greater than 1. Conclusions The research findings revealed the change of NO concentration in arterial-capillary-venous vessels due to the change of ventilation as well as the dynamic regulation mechanism of NO in blood vessels, and predicted the effective value range of α，thus providing theoretical basis for further research on the mechanism of blood flow, ventilation perfusion ratio affected by vasoconstriction and vascular resistance changes due to ventilation insufficiency.
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Objective:To evaluate the effectiveness and safety of endovascular treatment in solving symptomatic cerebral artery tandem lesions.Methods:From June 201 2 to February 201 4,1 2 cases (24 lesions)with symptomatic cerebral artery tandem lesions were accepted for the endovascular treatment. The distributions of the tandem lesions were as follows:the common carotid artery and internal carotid ar-tery (1 case),the internal carotid artery and the proximal of the carotid cavernous sinus segment (3 ca-ses),the internal carotid artery and the distal of the carotid cavernous sinus segment (4 cases),the in-tracranial segment of internal carotid artery and middle cerebral artery M1 segment (2 cases),the first segment of vertebral artery and intracranial segment of vertebral artery (2 cases).All of these cases were treated from distal lesions to proximal lesions except for tandem lesions in the internal carotid artery and the distal of the carotid cavernous sinus segment in order to obtain better support.Tandem lesions were treated in the same operation with local anesthesia or general anesthesia.The procedures of the 1 2 cases retrospectively were analyzed and the peri-operation complications and responsibility region recurrent is-chemic stroke incidents observed.Results:All tandem lesions were solved successfully all at once.There were no peri-operation complications or recurrent ischemic stroke incidents.There were no recurrent is-chemic stroke incidents or stent restenosis cases in the follow-up.Conclusion:It is safe and effective for selective endovascular treatment in solving symptomatic cerebral artery tandem lesions at the same time, but we should take careful preoperative evaluation and improve the operation plan.
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Objective:To analyze correlation factors of hemodynamic damage after carotid artery stenting.Methods:In this study, 66 cases (71 lesions) who undertook carotid artery stenting were col-lected and the correlation factors of hemodynamic damage were analyzed .Results:Hemodynamic damage emerged in 23 cases (32.4%), of which, 11.3%developed hypotension.The distance between bifurca-tion and lesions (P=0.002 0), plaque distribution (P=0.000 2), plaque character (P=0.001 9), post-dilation ( P =0.002 6 ) were associated with hemodynamic damage by single factor analysis . However, only eccentric plaque (P=0.015 3) and calcified plaque (P=0.009 7) were associated with hemodynamic damage by multiple factors analysis .All the patients could reach stable circulation by drugs during operation , and no cerebral ischemic events ( transient ischemic attack or stroke ) and cardiovascu-lar ischemic events happened .Conclusion: The distance between bifurcation and lesions , eccentric plaques, calcified plaques are correlation factors of hemodynamic damage .
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Objective:To anslysis the hemodynamic states of vertebrobasilar dolichoectasia based on computational fluid dynamics technique.Methods:The original DICOM format image data from a patient with vertebrobasilar dolichoectasia (VBD), were imported by the Mimics software directly,and the 3D Objects were constructed.The simulation of model was made with Ansys software, the hemodynamic pa-rameters such as streamlines, wall shear stress( WSS) and wall pressure were described.Results:There was stable laminar flow in proximal basilar artery and was no blood flow mixed by bilateral vertebral arter-y.However, Spiral flows were appeared in distal tortuous basilar artery.The low WSS regions in the ver-tebra-basilar junction section and inferior segment of basilar artery were coincide with the high wall pres-sure regions.It could be speculated the initial growth regions might be located in the vertebra-basilar junction section and inferior segment of basilar artery.Local regions with low WSS and high wall pressure might be associated with the occurrence and development of VBD.Conclusion: CFD numerical simula-tion maybe can provide a theoretical basis for the role of hemodynamic factors in occurrence and develop-ment of VBD.
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Objective:To study the morphology of middle cerebral artery ( MCA ) M1 segment .Me-thods:We selected the MRA data of 794 MCA (400 of the left side and 394 of the right side ) from Ja-nuary 1, 2011 to June 30, 2011 consecutively and analyzed the morphology of the MCA M 1 segment in axial, anteroposterior and lateral view , measured the length of the M1 segment, and analyzed the simila-rity of the left and right side M1 segment morphology .Results:In axial, anteroposterior and lateral view , the MCA M1 segment showed C-shape >L-shape >S-shape .In axial view , it was about 373 ( 47%) M1 segment performance for the C-shape, of which 340 (42.8%) M1 segments showed bowing to the dorsal side, only 33 (4.2%) M1 segments showed bowing to the ventral side .In anteroposterior view, it was about 322 (40.6%) M1 segments of the performance of the C-shape, of which 262(33.0%) M1 segments showed a bowing to the superior , 60 (7.6%) showed bowing to the inferior .The similarity of the left and right MCA M1 segments was 27.2% (114/419) in axial view and 42.7% (179/419) in anteroposterior view.It was more similar in anteroposterior view than in axial view .Along with the increase of age, in the axial view, L-shape converted to C-shape very obviously, but only mildly elevated in S-shape .In anteroposterior view , the L-shape converted to the C-shape or S-shape along with the increase of age.Conclusion:The different morphology of MCA M1 segment in axial and anteroposterior view may be involved in the development of intracranial atherosclerosis .
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Objective To study the clinical characteristics and treatment strategy for isolated dissection of the superior mesenteric artery (SMA).Methods Clinical data of 19 consecutive patients with IDSMA were retrospectively analyzed.There were 15 men and 4 women.The mean age was 56 ± 12 (41-84) years old.Fifteen patients presented with abdominal pain and 4 patients had no symptom.The dissections were diagnosed by contrast-enhanced computed tomography in 18 patients and ultrasonography in 1 patient.Results The dissections were located at the anterior wall of the curvature part of the SMA in all 19 patients.Asymptomatic patients underwent conservative management.One asymptomatic patient with aneurysmal dilation was managed by stent and the 15 symptomatic patients underwent endovascular management.During the mean 7-46 (21 ± 10) months follow-up period,all patients were asymptomatic with patency of SMA.Conclusions The dissection was located at the anterior wall of the curvature part of the SMA.Conservative management can be applied to the asymptomatic patients.For symptomatic patients without intestinal necrosis or artery rupture,stent implantation is recommended,and the curvature of SMA should be covered completely.Endovascular spasmolysis is helpful in relieving pain.
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ObjectiveTo compare two treatment methods for acute iliofemoral vein thrombosis:c atheter-directed pharmacomechanical thrombolysis (CDPT,47 cases) and intervention combined surgicaltherapy( IST,14 cases).MethodsThis study includes 61 patients of acute iliofemoral vein thrombosis treated by CDPT or IST.All discharged cases were followed up by telephone for a period of 14 -37 months.ResultsAmong the 61 patients (64 extremities),47 (forty-seven extremities) treated by CDPT,and 14 cases (seventeen extremities) treated by IST.The IST group included three patients of bilateral iliofemoral vein thrombosis,five patients on postoperative status within one month,and three patients in which the iliofemoral vein was not accessible.When discharged from hospital,the effective rate of edema relief is 93.6％ in CDPT group while that is 94.1％ in IST group; Melena occurred in one patient of CDPT group and incision hematoma occurred in one patient of IST group.According to the results of 14 -37 months follow-up,the effective rate of edema relief is 85.0％ in CDPT group while that is 85.7％ in IST group ( x2 =0.004 and the P =0.948).Calf pigmentation occurred in only one patient of CDPT group.The patency rate of vein by BUS examination is 52.6％ in CDPT group while that is 84.6％ in IST group x2 =4.157,P =0.041 ).ConclusionsComparing with CDPT group,IST group has the similar effective rate of edema relief,but has higher patency rate of iliofemoral vein.In case of bilateral acute iliofemoral vein thrombosis,in patients in whom thrombolysis is contraindicated,or when the iliofemoral vein is not accessible,IST is the treatment of choice for acute iliofemoral vein thrombosis.
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Objective To investigate the safety and feasibility of femoral vein thrombectomy for patients with acute deep vein thrombosis in the lower limbs.Methods During June 2003 to August 2006,a succession of 43 patients with acute deep vein thrombosis in the lower extremities received femoral vein thrombectomy in our hospital.An inferior vena cava filter was employed before the operation.Anticoagulation and regional thrombolysis were taken postoperatively.Analyse the data of operation procedure,curative effect and complications.Results The operation time ranged from 55 to 115 minutes with a mean of 92.6 minutes.Four of the patients received blood transfusion during the operation.The mean blood loss was 384.6 ml (100 to 1000 ml).Five patients showed transient fluctuation of blood pressure during the surgery.None of the patients had pulmonary embolism during and after the operation. Five patients developed lymph leakage from the incision at the inguinal area,and was cured in 1 week.One aged patient suffered from postoperative postatic pneumonia and was cured before being discharged;no other complications were found in this series.The thrombectomy achieved good outcomes in our patients.The edema and pain in the lower limbs were relieved quickly after the operation, the difference between the circumferences of the two legs decreaed from a median of 5.5 cm (thigh) and 4.0 cm (crus) to 1.5 cm and 1.0 cm (Z=-5.345,P=0.000 and Z=-5.461,P=0.000),respectively,32 of the patients received re-examination 6 months postoperation,none of them showed recurrent thrombosis.Conclusions Femoral vein thrombectomy is feasible and safe for serious acute deep vein thrombosis in the iliac and femoral veins.Patients can recover quickly after the operation.
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Objective:To summarize the curative effect in treatment of Raynaud's syndrome with chemical thoracic sympathectomy(CTS) guided by X-ray since 2001.Methods: From March 2001 to August 2007,97 patients with Raynaud's syndrome(186 limbs) were treated by CTS.Guided by X-ray,a needle was punctured through the back skin to the second thoracic sympathetic ganglion beside the thoracic vertebrae and 2 mL of 5%(v/v) phenol was injected.Results: The first CTS treatment produced a good effect on 146 limbs with an effective rate of 78.5%(146/186).The same treatment was performed on the limbs with no effect 1-2 days after the first treatment and produced good effect on 13 limbs with an effective rate of 32.5%(13/40).The total effective rate of the patients who were hospitalized for the first time was 85.5%(159/186).Of the 97 patients,78 patients(80.4%) were followed up for 47 months on an average with an effective rate of 69.5%.And the rate of complications was 11.4% for pheumothorax,and 3.9% for hydrothorax.Hyperalgesia on axillary region and anterior chest wall;Horner syndrome and sinus bradycardia were rare.Conclusion: CTS is minimally invasive and effective in treatment of Raynaud's syndrome.
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SUMMARY Tuberculous aneurysm of the aorta is a very rare disorder. There have been only 50 reported cases of tuberculous aneurysm since 1895 till now, of which 88% were false aneurysms with majority being single in number. And only four were found to have multiple tuberculous aneurysms. The mean ages of the patients were 50?16 years. Treatment of tuberculous aortic aneurysm must be a combined medical and surgical approach. Once tuberculous aneurysm is identified, surgery must be performed promptly. The size of the aneurysm does not influence the need for surgery. A 70-year-old male with intermittent episodes of abdominal pain after receiving an inappropriate antitubercular therapy for pulmonary tuberculosis was diagnosed as multiple false tubercular aneurysm of abdominal aorta. An aneurysm of base 3.3 cm and greatest diameter 5 cm?6 cm was seen just above the opening of Coeliac trunk. Also at the dorsal aspect of abdominal aorta and superior mesenteric artery junction and ventral aspect of renal artery false aneurysms were seen, each with the size of 1 cm in diameter. Apart from antitubercular and antimicrobial treatment, first line surgery Endovascular Exclusion of Abdominal Aortic Aneurysm was performed for ruptured false abdominal aortic aneurysm. Even before the second line surgery, smaller abdominal aortic aneurysms got ruptured and the patient ’s party gave up further treatment. Finally the patient died of gastrointestinal haemorrhage.