止浆塞外塞胶料的设计及优化

设计一种新型具有密封和排气功能的止浆塞,采用有限元方法对止浆塞的实际工作状态进行数值模拟分析,对外塞胶料进行优化。结果表明:随着止浆塞外塞胶料的硬度的减小,止浆塞的密封性能提高;综合考虑密封性能和成本,确定止浆塞外塞采用邵尔A型硬度为40度的天然橡胶胶料。

浅析“阳虚则外寒,阴虚则内热,阳盛则外热,阴盛则内寒”

浅析“阳虚则外寒，阴虚则内热，阳盛则外热，阴盛则内寒”晋中地区卫生学校（０３０８００）李志敏太原市中心医院姬爱冬关键词阳虚阴虚阳盛阴盛《素问·调经论》指出：“阳虚则外寒，阴虚则内热，阳盛则外热，阴盛则内寒”。论述了阴阳盛衰产生的病理机转，对临床颇有指...

对撞式气流粉碎机加料系统的关键技术研究

螺旋加料器是对撞式气流粉碎机加料系统的核心部件。本文对螺旋加料器的主要参数进行计算,并对关键元件进行设计。圆柱齿轮减速器和直流电机构成了螺旋加料器的驱动部分;无级调速可以通过直流电机来实现,产量的大小由转速的快慢来控制;螺旋轴、螺旋管、筋条、外塞管、内塞管和传动部分在一起组成了螺旋加料器;为了实现均匀连续喂送原料,在螺旋加料器中使用了旋转螺旋;而将带槽的螺旋管安装在螺旋轴的周围的作用是为了实现连续加料。

与中心静脉穿刺置管相关的并发症

中心静脉穿刺置管是临床上应用很广的一项有创技术,一旦操作失误或管理不当,会引起各种并发症,甚至危 及生命。

前鼻孔和鼻瓣区形态异常矫治的临床意义

鼻呼吸不畅,除鼻腔、鼻甲、鼻窦病变外,前鼻孔和鼻瓣区、鼻阈的结构异常也是影响鼻呼吸的重要因素。矫正这些异常结构,扩大重塑前鼻孔和鼻瓣区形态结构,可消除鼻呼吸的障碍,恢复生理气流流场。

Multipoint Infrared Telemetry System for Measuring the Piston Temperature in Internal Combustion Engines

A high precision, high antijamming multipoint infrared telemetry system was developed to measure the piston temperature in internal combustion engine. The temperature at the measuring point is converted into corresponding voltage signal by the thermo-couple first. Then after the V/F stage, the voltage signal is converted into the frequency signal to drive the infrared light-emitting diode to transmit infrared pulses. At the receiver end, a photosensitive audion receives the infrared pulses. After conversion, the voltage recorded by the receiver stands for the magnitude of temperature at the measuring point. Test results of the system indicate that the system is practical and the system can perform multipoint looping temperature measurements for the piston.

A study of pulmonary embolism after abdominal surgery in patients undergoing prophylaxis

AIM： To determine risk factors for pulmonary embolism and estimate effects and benefits of prophylaxis. METHODS： We included 78 patients who died subsequently to a pulmonary embolism after major abdominal surgery from 1985 to 2003. A first, retrospective analysis involved 41 patients who underwent elective surgery between 1985 and 1990 without receiving any prophylaxis. In the prospectively evaluated subgroup, 37 patients undergoing major surgery between 1991 and 2003 were enrolled： all of them had received a prophylaxis consisting in lowmolecular weight heparin, given subcutaneously at a dose of 2850 IU AXa/0.3 mL （body weight 〈 50 kg） or 5700 IU AXa/0.6 mL （body weight ≥ 50 kg）. RESULTS： A higher incidence of thromboembolism （43.9% and 46.34% in the two groups, respectively） was found in older patients （〉 60 years）. The incidence of pulmonary embolism after major abdominal surgery in patients who had received the prophylaxis was significantly lower compared to the subjects with the same condition who had not received any prophylaxis （P 〈 0.001, OR = 2.825; 95% CI, 1.811-4.408）. Furthermore, the incidence of pulmonary embolism after colorectal cancer surgery was significantly higher compared to incidence of pulmonary embolism after other abdominal surgical procedures. Finally, the incidence of pulmonary embolism after colorectal cancer surgery among the patients who had received the prophylaxis （11/4316, 0.26%） was significantly lower compared to subjects undergoing a surgical procedure for the same indication but without prophylaxis （10/1562, 0.64%） （P 〈 0.05, OR = 2.522; 95% Ct, 1.069-5.949）. CONCLUSION： Prophylaxis with low molecular weight heparin is highly recommended during the preoperative period in patients with diagnosis of colorectal cancer due to high risk of pulmonary embolism after elective surgery.

Percutaneous transarterial embolization of extrahepatic arteroportal fistula

Arteroportal fistula is a rare cause of prehepatic portal hypertension. A 44-year-old male with hepatitis virus C infection was admitted for acute variceal bleeding. Endoscopy showed the presence of large esophageal varices. The ultrasound revealed a mass near the head of pancreas, which was characterized at the color- Doppler by a turbulent flow, and arterialization of portal vein flow. CT scan of abdomen showed a large aneurysm of the gastroduodenal artery communicating into the superior mesenteric vein. The sinusoidal portal pressure measured as hepatic vein pressure gradient was normal, confirming the pre-hepatic origin of portal hypertension. The diagnosis of extrahepatic portal hypertension secondary to arteroportal fistula was established, and the percutaneous embolization was performed. Three months later, the endoscopy showed absence of esophageal varices and ascites. At the moment, the patient is in good clinical condition, without signs of portal hypertension.

Lubrication characteristics of external return spherical hinge pair of axial piston pump or motor under combined action of inclination and offset distance

External return mechanism is a mechanical structure applied to axial piston pumps.To study its lubrication characteristics,the Reynolds equation applied to an external return spherical hinge pair was deduced based on the vector equation of relative-motion velocity of the external return spherical hinge pair under the influence of external swash plate inclination and offset distance.The results show that the total friction,axial leakage flow,and maximum value of the maximum oil-film pressure increase with increasing pump-shaft speed and decrease with increasing offset distance in one working cycle when the external-swash-plate inclination is constant.However,the varying offset distance has little effect on the axial leakage flow.The maximum value of the maximum oil-film pressure decreases with increasing external-swash-plate inclination and the total leakage flow increases with increasing external-swash-plate inclination in one working cycle when the offset distance is constant.It can be seen that the abovementioned parameters are important factors that affect the lubrication characteristics of external return spherical hinge pairs.Therefore,the complex effects of different coupling parameters should be comprehensively considered in the design of the external return mechanism.

Radiotherapy combined with transcatheter arterial chemoembolization for unresectable hepatocellular carcinoma–a prospective clinical trial

Objective: This study evaluated the therapeutic effect of external beam radiotherapy (RT) combined with trans- catheter arterial chemoembolization (TACE) on the patients with unresectable hepatocellular carcinoma (HCC). Methods: From June 1994 to April 2002, 114 patients with unresectable HCC were nonrandomized prospectively stepped into our study. All patients received TACE as initial therapy, except 54 also received combination therapy with external beam therapy. Sur- vival failure patterns were analyzed and compared between the two groups. Results: Overall survival rates in the patients in the radiotherapy group were 65%, 47%, 38% at 1, 2, 3 years, respectively, improved over the non-radiotherapy group rates of 54%, 36.5%, 18% at 1, 2, 3 years, respectively. There was significant difference between two groups (P < 0.05). The survival rates correlated with tumor size, number of tumors, and portal vein embolus. Conclusion: TACE combined with RT is a more effective treatment than TACE alone in patients with unresectable HCC.

Double Pulmonary Embolism and Left Common Iliac Vein Thrombosis after in vitro fertilization and embryo transfer： a Case Report

This article discusses the mechanism, diagnosis, and treatment of a case of double pulmonary embolism and left common iliac vein thrombosis following in vitro fertilization （IVF） and embryo transfer （ET） to arouse vigilance for unexpected thrombosis after ovarian hyperstimulation and to serve as a clinical reference of this condition. This paper reports the case of a woman with double pulmonary embolism and left common iliac vein thrombosis after IVF-ET and the successful management of this condition. The woman had primary infertility, and underwent IVF-ET with 14 ooeytes recovered and two embryos transferred. The patient suffered breathing difficulty 17 days after the ET, and was hospitalized 6 days later as her condition had exacerbated. Computed tomographic （CT） angiography of pulmonary arteries showed double pulmonary embolism, left common iliae vein thrombosis, abnormal density shadow in uterine appendages, and ascites. A healthy baby boy and girl were safely delivered by Caesarean section after successful treatment. Thrombosis after IVF-ET is an uncommon but life-threatening complication and concurrent pulmonary embolism is even rarer. It is suggested that careful thrombosis risk assessment be taken before therapy and particular attention be paid to patients with special body constitutions to develop thrombosis. Whenever patients experience breathing difficulty after IVF-ET, it is strongly advised to examine the possibility of pulmonary embolism. The main treatments for thrombosis are anticoagulant therapy by low-molecular-weight heparin and thrombolysis by urokinase.

Aggressive surgical management after transarterial chemoembolization(TACE)for liver metastases from ocular melanoma

Metastatic melanoma is also a challenge for surgeons. Recently, it has been reported that aggressive surgery combined with supportive therapy may be potential benefit for the condition. Therefore, we report a case of ocular melanoma metastatic to multiple visceral sites treated by cytoreductive surgery after initial intra-,arterial hepatic chemoembolization

Aroma Properties of Selected Local Spices of Akwa Ibom State of Nigeria

Some famous local spices were selected to determine their potentials in terms of their aroma and utilization. They included Tea Bush （Ocimum basilicum）, Guinea Black Pepper （Piper guineense）, African Pepper （Xylopia aethiopica）, Alden Tree （Tetrapleura tetraptera） and the African Meg Nut or Onion Tree （Blighia unijugata）. Essential oils were extracted from the samples and used for aroma absorption test in a uv-visible spectrometer V2.03. The intensity of aroma was indicated at some peak values of absorption at particular wavelengths. The compounds responsible for the aroma at this peak values were identified by matching their wavelengths with those of known compounds at similar wavelengths of absorption. Thus, a compound such as Quinoline that has hot strong aroma and little bleaching effect was proved to be present in Guinea black pepper ;at the wavelength of 313.0 nm. Benzene with hot strong aroma and flammable effect was also indicated in this spice at the wavelength of 253.0 rim. Proximate analysis carried out showed that these spices have high nutritive values. Some of them such as Guinea black pepper, African Nutmeg and Ethiopian （African） pepper had high ether extract of 20.01, 25.97 and 31.25 respectively, and could be regarded as oil seeds, they contain much of essential oils.

Effects of extrinsic positive end-expiratory pressure on work of breathing in patients with chronic obstructive pulmonary disease

Objective To investigate the effects of extrinsic positive end-expiratory pressure (PEEPe) on work of breathing in patients with chronic obstructive pulmonary disease (COPD) and their corresponding mechanism.Methods Ten ventilated patients with COPD were included in the study. A Bicore CP-100 pulmonary monitor (Bicore Monitoring System, USA) was used for monitoring respiratory mechanics. First, dynamic intrinsic positive end-expiratory pressure (PEEPi,dyn) was measured when PEEPe was zero, which was called PEEPi,dynz. Then the PEEPe was set randomly at 0%, 40%, 60%, 80% and 100% of PEEPi,dynz respectively. Pulmonary mechanics and other parameters (heart rate, blood pressure and blood gas analysis) were measured 30 minutes after the level of PEEPe was changed.Results Work of breathing patient (WOBp), pressure time product, difference of esophageal pressure and PEEPi,dyn decreased significantly when PEEPe was applied, and continued decreasing as PEEPe was increased. Work of breathing ventilator increased significantly when PEEPe was increased to 80% and 100% of PEEPi,dynz. Significantly positive linear correlation was found between the changes in WOBp and in PEEPi,dyn.Conclusions WOBp decreases gradually as PEEPe is increased. WOBp decreases by narrowing the difference between the alveolus pressure and the central airway pressure at the end of expiration when PEEPe is applied.

Retrospective study on the endovascular embolization for traumatic carotid cavernous fistula

Objective： To retrospectively analyze 95 cases of traumatic carotid cavernous fistula treated by endovascular embolization. Methods： From January 1994 to December 2008, 95 patients with traumatic carotid cavernous fistula were treated in our hospital. All patients received selective cerebral angiography through femoral artery catheterization. Accordingly, 89 cases were treated by detachable balloon embolization, 5 by platinum microcoils and 1 by coveredstem, respectively. Results： In the study, 61 cases achieved successful balloon embolization at the first time. Fifty-six cases had multiple balloons due to the big fistula. Nine cases received balloon embolization twice. But among the 5 patients treated with platinum microcoils, one developed slight brainstem ischemia. After operation the patient had herniparesis and swallow difficulty, but gradually recovered 3 months later. No neurological deficits were observed in other cases. All the cases recovered. Eighty-five cases were followed up for 1-15 years and no recurrence was found. Conclusions： The endovascular embolization for traumatic carotid cavernous fistula is minimally invasive, safe, effective and reliable. The detachable balloon embolization is the first choice in the treatment of TCCF.

Study on intraluminal embolization with microcoils treating traumatic pseudoaneurysms in common carotid artery in rabbits

Objective: To evaluate the long-term effect of endovascular occlusion with microcoils on traumatic pseudoaneurysms (TPAs) in the common carotid artery in rabbits.Methods: TPAs in the right common carotid artery were surgically made in 16 rabbits. At 3-4 weeks after operation, the survived 12 models were randomly divided into a control group (n=3) with no treatment and an experimental group (n=9), in which TPAs were intraluminally embolized with microcoils and corresponding therapy was given. Three months after embolization, the TPAs were examined with digital subtraction angiography and pathology. Results: The 3 rabbits in the control group all died of rupture of TPA. Among the 9 TPAs occluded with microcoils, 4 were completely occluded, 4 were partially occluded, and 1 was excluded due to the microcoils migrating into the parent artery. Three months after embolization, the 4 TPAs which were completely occluded remained obliterated as determined by digital subtraction angiographic findings. The parent artery remained unobstructed and the structure of the TPAs were replaced by a mass of scar tissues. The 4 TPAs which were partially occluded remained unruptured and the microcoils were compressed.Conclusions: The lumen in TPA can be completely occluded by microcoils and the parent artery is unblocked. Partial occlusion of the lumen can also prevent the rupture of TPA.