The new forming process of AA6061 alloy tube, including solution treatment, granule medium internal high-pressure forming and aging treatment, was developed. The AA6061 alloy tube via heat treatment satisfied the form...The new forming process of AA6061 alloy tube, including solution treatment, granule medium internal high-pressure forming and aging treatment, was developed. The AA6061 alloy tube via heat treatment satisfied the forming requirement, and the granule medium internal high pressure forming method for AA6061 alloy tube was also realized by using convenient implementation with low requirement of equipment and flexible design of product. At a solution temperature of 560℃ and time of 120 min, the elongation of the AA6061 extruded tube increases by 300% and the strength and the hardness dramatically decrease too. Therefore, the AA6061 alloy tube meets the requirement of internal high-pressure forming because of the improvement of formability. The experiments shows that the strength and hardness of AA6061 alloy workpiece recover to that of the as-received alloy at an aging temperature of 180℃ and time of 360 min, and the strength of AA6061 alloy workpiece is equal to the base alloy. The typical parts of convex ring tube, stepped shaft tube and hexagonal tube were successfully produced in lab by using the present forming method. The forming tests show that the maximum expansion ratio(MER) of the AA6061 extruded tube increases by 25.5% and the material properties of formed AA6061 alloy tube reached the performance of as-received alloy.展开更多
BACKGROUND： In the perspective of traditional Chinese medicine, few studies have focused on the compound preparations though there are many investigations. The present study was undertaken to investigate the effect o...BACKGROUND： In the perspective of traditional Chinese medicine, few studies have focused on the compound preparations though there are many investigations. The present study was undertaken to investigate the effect of Zhenwu Tang Granule on chronic pressure-overloaded left ventricular hypertrophy in rats.METHODS： The study was performed at the laboratory of Guangzhou Institute of Respiratory Disease. Male SD rats were divided randomly into 3 groups： sham operation group （n=8）, operation group （n=15） and traditional Chinese medicine （TCM） group （n=15）.The model of myocardial hypertrophy was made by gradually constricting the abdominal aorta. Sixteen weeks later, cardiac ultrasonography was performed in all groups in order to ascertain post-operational left ventricular （LV） hypertrophy. And Zhenwu Tang Granule was added at a dose of 12 g/kg in the mixed feedstuff for 8 weeks in the TCM group. In the 24th week, weight, structure as well as function of the heart in each group were measured by high-frequency ultrasonography, and Masson＇s staining was performed on the cardiac muscles. Meanwhile, total collagen volume fraction （CVF-T） and non-coronary vessel collagen volume fraction （CVF-NV） were analyzed.RESULTS： There was an increase in the weight of the heart in the operation group, with the left ventricule dominated （P〈0.05）. The heart was enlarged, with diastolic interventricular septal distance （IVSd） and left ventricular posterior wall distance （LVPWd） dominated （P〈0.01）.There was a significant decrease in the cardiac function （P〈0.05）. The weight （P〈0.01） and volume of the heart decreased in the TCM group compared with the operation group, with IVSd and systolic left ventricular posterior wall dominated （P〈0.01）. And the cardiac function was improved （P〈0.05）. Significant interstitial and collagen hyperplasia was shown in the operation group based on pathological analysis, and various improvements were proved in the TCM group, i.e. there was a significant decrease in CVF-T and CVF-NV （P〈0.01） compared with the operation group; but no difference （P〉0.05） was found when compared with the pseudo-operation group.CONCLUSION： Zhenwu Tang Granule could reduce the weight and volume of the heart, improve the cardiac function, inhibit hyperplasia of collagen, and reverse myocardial hypertrophy in rats with pressure-overloaded left ventricular hypertrophy.展开更多
There is reason to believe that the vagus nerve carries sensory afferent messages from the intracranial cavity as it does from the other body cavities. Considering the arachnoid granulations as a secretory apparatus i...There is reason to believe that the vagus nerve carries sensory afferent messages from the intracranial cavity as it does from the other body cavities. Considering the arachnoid granulations as a secretory apparatus instead of an organ transporting cerebrospinal fluid, a simple model can be built. Assuming that the arachnoid granulations produce nitric oxide in accordance with changes in the intracranial pressure, the jugular foramen with the vagus nerve lying just subendothelially is where this message would be received. Other chemical substances from the granulations or other intracranial tissues could of course also act as messengers. This would mean that the brain stem could adjust to changes in intracranial pressure with small changes in cerebral venous resistance. The general idea is that intracranial pressure is a passive function of the intracranial pressure-volume relationship. But the hypothesis suggests that the vagus nerve constantly mediates changes in intracranial pressure to the brain stem that can rapidly adjust cerebral venous resistance. This control is totally intracranial and easily overridden by considerable changes in absorption of spinal fluid or intracranial calamities. This article looks for clues in support of the idea that the vagus nerve mediates intracranial pressure changes to the brain stem.展开更多
In order to understand the effect of low temperature on the formation process of aerobic granules and contaminants removal characteristics,the aerobic granules-membrane bioreactor (AGS-MBR) has been started up and ope...In order to understand the effect of low temperature on the formation process of aerobic granules and contaminants removal characteristics,the aerobic granules-membrane bioreactor (AGS-MBR) has been started up and operated at low temperature using the carbon resource of sodium acetate. Aerobic granules cultivated in AGS-MBR possess smooth surface and compact structure in morphology as well as better settling property and higher biomass after 38 days. The average parameters of aerobic granules are: diameter 3. 1 mm,wet density 1. 041 g/mL,sludge volume index 42. 35 mL/g and settling velocity 20. 6 - 45. 2 cm/min. During the start-up of AGS-MBR,the respectively average contaminants removal efficiencies at low temperature are 91. 9% for chemical oxygen demand (COD) ,89. 2% for NH4 + -N and 86. 3% for PO43- -P,and the overgrowth of filamentous bacteria has been well controlled. In addition,the hollow fiber microfiltration (MF) membrane fouling is light and the regime membrane layer is capable of enhancing membrane filtration as well as the average growth of trans-membrane pressure (TMP) is 1. 07 kPa/d. Compared with the conventional cultivation of aerobic granules,the sludge granulation time significantly decreases from 73 days to 38 days by the application of microfiltration membrane at low temperature.展开更多
Normal pressure hydrocephalus is a devious phenomenon. It is a disease that is difficult to diagnose and difficult to treat, the only treatment being a ventriculo-peritoneal shunt, though good shunting results rarely ...Normal pressure hydrocephalus is a devious phenomenon. It is a disease that is difficult to diagnose and difficult to treat, the only treatment being a ventriculo-peritoneal shunt, though good shunting results rarely pass a 70% level of effectiveness. We need to understand its pathophysiology better before things will improve. Although some colleagues know it as a possible “reversible dementia” others hardly know about its existence. Solutions would also have value for the general understanding of hydrocephalus of other types. Many theories have been published recently in the search for the missing pieces in this puzzle and I feel that my own postulations could turn out to be useful. After years of diagnosing and operating on hydrocephalus patients I propose that: 1) There is reason to believe that patients with the Apoprotein E3/3 genotype and a high head size percentile are particularly vulnerable to developing idiopathic normal pressure hydrocephalus (iNPH). 2) The classical theory that the arachnoid granulations (AG) transport cerebrospinal fluid (CSF) into the venous circulation is wrong. I postulate, that the AG essentially are sensors, registering the pressure differences between the CSF in the subarachnoidal space at the top of the skull and the venous pressure in the sagittal sinus. The AG’s endothelium produces nitric oxide (NO) as a messenger that is received by the vagus nerve at the jugular foramen. 3) The disease has its fundamental pathology in the subpial space in the large cisternas and along the large vessels under the brain. Here the intravenous absorption of cerebrospinal fluid (CSF) takes place. Cerebrospinal fluid is transported into the subpial venules and veins, driven by the pulse pressure of the subpial arteries. Morphological changes in the pial/subpial anatomy explain the existence of acquired normal pressure hydrocephalus (aNPH).展开更多
目的探讨静脉性耳鸣患者蛛网膜颗粒内脑疝(brain herniation into arachnoid granulation,BHAG)对于横窦跨狭窄压力梯度(tra ns-stenostic pressure gradient,TPG)升高(≥8m m H g)的诊断效能。方法回顾性分析2010年11月至2023年10月于...目的探讨静脉性耳鸣患者蛛网膜颗粒内脑疝(brain herniation into arachnoid granulation,BHAG)对于横窦跨狭窄压力梯度(tra ns-stenostic pressure gradient,TPG)升高(≥8m m H g)的诊断效能。方法回顾性分析2010年11月至2023年10月于首都医科大学附属北京友谊医院住院的静脉性耳鸣患者临床及影像学资料,所有患者均行静脉窦非增强M RV(non-contrast enhanced MR venography,NCE-MRV)、全脑MPRAGE及3D-T_(2)WI扫描,并经DSA行静脉窦测压,将患者分为A(TPG<8 mm Hg)、B(TPG≥8 mm Hg)两组。结合全脑MPRAGF及3D-T_(2)WI的标准冠状面图像,评价是否存在BHAG。对A、B两组BHAG发生率是否存在差异进行卡方检验;计算BHAG对于诊断高TPG(≥8 mm Hg)特异度、灵敏度、准确度、阳性预测值及阴性预测值。结果共73例患者符合纳排标准(男性9例,女性64例),年龄37.0(46.5-30.0)岁,其中A组(TPG<8 mm Hg)46例,B组(TPG≥8 mm Hg)27例。BHAG患者共12例(12/73,16.44%),A、B两组BHAG发生率存在统计学差异(χ^(2)值=10.96,P<0.001)。BHAG诊断高TPG(≥8mmHg)的特异度为95.65%、灵敏度为37.04%、准确度为73.97%、阳性预测值为83.33%,阴性预测值为72.13%。结论BHAG在静脉性耳鸣患者中并不罕见,可用于辅助预估有无TPG升高。展开更多
Objective： To study the effect and mechanism of Tianhuang Granule （田黄冲剂, THG） on hydrocephalus in the patients with acute cerebral hemorrhage （ACH） through intracranial pressure （ICP） monitoring, serum matr...Objective： To study the effect and mechanism of Tianhuang Granule （田黄冲剂, THG） on hydrocephalus in the patients with acute cerebral hemorrhage （ACH） through intracranial pressure （ICP） monitoring, serum matrix metalloproteinase-9 （MMP-9） level observation, and National Institutes of Health Stroke Scale （NIHSS） scoring （for nerve function deficit）. Methods： Sixty patients with ACH were equally randomized into two groups by lottery, the control group and the THG group; all were treated with conventional therapy, but to the patients in the THG group, THG was given orally in addition for 28 days. Changes of ICP, MMP-9 expression, and NIHSS scores, as well as the degree of cerebral hematoma and hydrocephalus （by cranial CT scanning） in the patients, were estimated and compared. Results： （1） ICP was lowered more significantly in the THG group, showing a significant difference between groups on day 7 （P〈0.05）. （2） MMP-9 expression was down-regulated in the THG group more significantly and earlier than that in the control group. （3） The degrees of cerebral hematoma and hydrocephalus in the THG group on day 7 were reduced significantly as compared with those on day 3 （P〈0.05）, but in the control group, the day of significant reduction was delayed to day 14, and the degrees on day 7 and day 14 in the two groups were significantly different （P〈0.05 and P〈0.01）. （4） NIHSS score was significantly lower in the THG group than that in the control group on day 14 and day 28 （P〈0.05 and P〈0.01）. Conclusion： THG can effectively lower ICP, down-regulate MMP-9 expression, promote the absorption of cerebral hematoma and hydrocephalus, and improve the nerve function, showing a clinical effectiveness than conventional therapy.展开更多
基金Project(51305386)supported by the National Natural Science Foundation of ChinaProject(E2013203093)supported by the Natural Science Foundation of Hebei Province,China
文摘The new forming process of AA6061 alloy tube, including solution treatment, granule medium internal high-pressure forming and aging treatment, was developed. The AA6061 alloy tube via heat treatment satisfied the forming requirement, and the granule medium internal high pressure forming method for AA6061 alloy tube was also realized by using convenient implementation with low requirement of equipment and flexible design of product. At a solution temperature of 560℃ and time of 120 min, the elongation of the AA6061 extruded tube increases by 300% and the strength and the hardness dramatically decrease too. Therefore, the AA6061 alloy tube meets the requirement of internal high-pressure forming because of the improvement of formability. The experiments shows that the strength and hardness of AA6061 alloy workpiece recover to that of the as-received alloy at an aging temperature of 180℃ and time of 360 min, and the strength of AA6061 alloy workpiece is equal to the base alloy. The typical parts of convex ring tube, stepped shaft tube and hexagonal tube were successfully produced in lab by using the present forming method. The forming tests show that the maximum expansion ratio(MER) of the AA6061 extruded tube increases by 25.5% and the material properties of formed AA6061 alloy tube reached the performance of as-received alloy.
文摘BACKGROUND： In the perspective of traditional Chinese medicine, few studies have focused on the compound preparations though there are many investigations. The present study was undertaken to investigate the effect of Zhenwu Tang Granule on chronic pressure-overloaded left ventricular hypertrophy in rats.METHODS： The study was performed at the laboratory of Guangzhou Institute of Respiratory Disease. Male SD rats were divided randomly into 3 groups： sham operation group （n=8）, operation group （n=15） and traditional Chinese medicine （TCM） group （n=15）.The model of myocardial hypertrophy was made by gradually constricting the abdominal aorta. Sixteen weeks later, cardiac ultrasonography was performed in all groups in order to ascertain post-operational left ventricular （LV） hypertrophy. And Zhenwu Tang Granule was added at a dose of 12 g/kg in the mixed feedstuff for 8 weeks in the TCM group. In the 24th week, weight, structure as well as function of the heart in each group were measured by high-frequency ultrasonography, and Masson＇s staining was performed on the cardiac muscles. Meanwhile, total collagen volume fraction （CVF-T） and non-coronary vessel collagen volume fraction （CVF-NV） were analyzed.RESULTS： There was an increase in the weight of the heart in the operation group, with the left ventricule dominated （P〈0.05）. The heart was enlarged, with diastolic interventricular septal distance （IVSd） and left ventricular posterior wall distance （LVPWd） dominated （P〈0.01）.There was a significant decrease in the cardiac function （P〈0.05）. The weight （P〈0.01） and volume of the heart decreased in the TCM group compared with the operation group, with IVSd and systolic left ventricular posterior wall dominated （P〈0.01）. And the cardiac function was improved （P〈0.05）. Significant interstitial and collagen hyperplasia was shown in the operation group based on pathological analysis, and various improvements were proved in the TCM group, i.e. there was a significant decrease in CVF-T and CVF-NV （P〈0.01） compared with the operation group; but no difference （P〉0.05） was found when compared with the pseudo-operation group.CONCLUSION： Zhenwu Tang Granule could reduce the weight and volume of the heart, improve the cardiac function, inhibit hyperplasia of collagen, and reverse myocardial hypertrophy in rats with pressure-overloaded left ventricular hypertrophy.
文摘There is reason to believe that the vagus nerve carries sensory afferent messages from the intracranial cavity as it does from the other body cavities. Considering the arachnoid granulations as a secretory apparatus instead of an organ transporting cerebrospinal fluid, a simple model can be built. Assuming that the arachnoid granulations produce nitric oxide in accordance with changes in the intracranial pressure, the jugular foramen with the vagus nerve lying just subendothelially is where this message would be received. Other chemical substances from the granulations or other intracranial tissues could of course also act as messengers. This would mean that the brain stem could adjust to changes in intracranial pressure with small changes in cerebral venous resistance. The general idea is that intracranial pressure is a passive function of the intracranial pressure-volume relationship. But the hypothesis suggests that the vagus nerve constantly mediates changes in intracranial pressure to the brain stem that can rapidly adjust cerebral venous resistance. This control is totally intracranial and easily overridden by considerable changes in absorption of spinal fluid or intracranial calamities. This article looks for clues in support of the idea that the vagus nerve mediates intracranial pressure changes to the brain stem.
基金Sponsored by the National High Technology Research and Development Program of China (863 Program,Grant No.2008AA06Z304)State Water Pollution Control and Harnessing of the Major Projects (Grant No.2009ZX07424-005)International Cooperation Program (Grant No.2010DFA92460)
文摘In order to understand the effect of low temperature on the formation process of aerobic granules and contaminants removal characteristics,the aerobic granules-membrane bioreactor (AGS-MBR) has been started up and operated at low temperature using the carbon resource of sodium acetate. Aerobic granules cultivated in AGS-MBR possess smooth surface and compact structure in morphology as well as better settling property and higher biomass after 38 days. The average parameters of aerobic granules are: diameter 3. 1 mm,wet density 1. 041 g/mL,sludge volume index 42. 35 mL/g and settling velocity 20. 6 - 45. 2 cm/min. During the start-up of AGS-MBR,the respectively average contaminants removal efficiencies at low temperature are 91. 9% for chemical oxygen demand (COD) ,89. 2% for NH4 + -N and 86. 3% for PO43- -P,and the overgrowth of filamentous bacteria has been well controlled. In addition,the hollow fiber microfiltration (MF) membrane fouling is light and the regime membrane layer is capable of enhancing membrane filtration as well as the average growth of trans-membrane pressure (TMP) is 1. 07 kPa/d. Compared with the conventional cultivation of aerobic granules,the sludge granulation time significantly decreases from 73 days to 38 days by the application of microfiltration membrane at low temperature.
文摘Normal pressure hydrocephalus is a devious phenomenon. It is a disease that is difficult to diagnose and difficult to treat, the only treatment being a ventriculo-peritoneal shunt, though good shunting results rarely pass a 70% level of effectiveness. We need to understand its pathophysiology better before things will improve. Although some colleagues know it as a possible “reversible dementia” others hardly know about its existence. Solutions would also have value for the general understanding of hydrocephalus of other types. Many theories have been published recently in the search for the missing pieces in this puzzle and I feel that my own postulations could turn out to be useful. After years of diagnosing and operating on hydrocephalus patients I propose that: 1) There is reason to believe that patients with the Apoprotein E3/3 genotype and a high head size percentile are particularly vulnerable to developing idiopathic normal pressure hydrocephalus (iNPH). 2) The classical theory that the arachnoid granulations (AG) transport cerebrospinal fluid (CSF) into the venous circulation is wrong. I postulate, that the AG essentially are sensors, registering the pressure differences between the CSF in the subarachnoidal space at the top of the skull and the venous pressure in the sagittal sinus. The AG’s endothelium produces nitric oxide (NO) as a messenger that is received by the vagus nerve at the jugular foramen. 3) The disease has its fundamental pathology in the subpial space in the large cisternas and along the large vessels under the brain. Here the intravenous absorption of cerebrospinal fluid (CSF) takes place. Cerebrospinal fluid is transported into the subpial venules and veins, driven by the pulse pressure of the subpial arteries. Morphological changes in the pial/subpial anatomy explain the existence of acquired normal pressure hydrocephalus (aNPH).
文摘目的探讨静脉性耳鸣患者蛛网膜颗粒内脑疝(brain herniation into arachnoid granulation,BHAG)对于横窦跨狭窄压力梯度(tra ns-stenostic pressure gradient,TPG)升高(≥8m m H g)的诊断效能。方法回顾性分析2010年11月至2023年10月于首都医科大学附属北京友谊医院住院的静脉性耳鸣患者临床及影像学资料,所有患者均行静脉窦非增强M RV(non-contrast enhanced MR venography,NCE-MRV)、全脑MPRAGE及3D-T_(2)WI扫描,并经DSA行静脉窦测压,将患者分为A(TPG<8 mm Hg)、B(TPG≥8 mm Hg)两组。结合全脑MPRAGF及3D-T_(2)WI的标准冠状面图像,评价是否存在BHAG。对A、B两组BHAG发生率是否存在差异进行卡方检验;计算BHAG对于诊断高TPG(≥8 mm Hg)特异度、灵敏度、准确度、阳性预测值及阴性预测值。结果共73例患者符合纳排标准(男性9例,女性64例),年龄37.0(46.5-30.0)岁,其中A组(TPG<8 mm Hg)46例,B组(TPG≥8 mm Hg)27例。BHAG患者共12例(12/73,16.44%),A、B两组BHAG发生率存在统计学差异(χ^(2)值=10.96,P<0.001)。BHAG诊断高TPG(≥8mmHg)的特异度为95.65%、灵敏度为37.04%、准确度为73.97%、阳性预测值为83.33%,阴性预测值为72.13%。结论BHAG在静脉性耳鸣患者中并不罕见,可用于辅助预估有无TPG升高。
基金Supported by the Special Fund for Integrative Chinese and Western Medical Researches of Tianjin City(No.07057)
文摘Objective： To study the effect and mechanism of Tianhuang Granule （田黄冲剂, THG） on hydrocephalus in the patients with acute cerebral hemorrhage （ACH） through intracranial pressure （ICP） monitoring, serum matrix metalloproteinase-9 （MMP-9） level observation, and National Institutes of Health Stroke Scale （NIHSS） scoring （for nerve function deficit）. Methods： Sixty patients with ACH were equally randomized into two groups by lottery, the control group and the THG group; all were treated with conventional therapy, but to the patients in the THG group, THG was given orally in addition for 28 days. Changes of ICP, MMP-9 expression, and NIHSS scores, as well as the degree of cerebral hematoma and hydrocephalus （by cranial CT scanning） in the patients, were estimated and compared. Results： （1） ICP was lowered more significantly in the THG group, showing a significant difference between groups on day 7 （P〈0.05）. （2） MMP-9 expression was down-regulated in the THG group more significantly and earlier than that in the control group. （3） The degrees of cerebral hematoma and hydrocephalus in the THG group on day 7 were reduced significantly as compared with those on day 3 （P〈0.05）, but in the control group, the day of significant reduction was delayed to day 14, and the degrees on day 7 and day 14 in the two groups were significantly different （P〈0.05 and P〈0.01）. （4） NIHSS score was significantly lower in the THG group than that in the control group on day 14 and day 28 （P〈0.05 and P〈0.01）. Conclusion： THG can effectively lower ICP, down-regulate MMP-9 expression, promote the absorption of cerebral hematoma and hydrocephalus, and improve the nerve function, showing a clinical effectiveness than conventional therapy.
