房室结逆向传导电生理特点的观察

目的研究房室结逆向传导的电生理特点。方法分析在我院行电生理检查和／或射频消融的成年患者中电生理资料比较完整的300例患者的房室结逆传电生理特点。结果射频消融术后有161例（54％）有房室结逆传。有逆传患者的前传功能要好于无逆传的患者，对于术后存在室房逆传的患者，逆传功能均明显差于前传功能。射频消融术后有28例（17％）经房室结逆传最早激动冠状静脉窦口，其逆传功能较最早激动希氏束电图的病例相比要差，而两者的前传功能差异无统计学意义。结论射频消融术后54％的患者存在房室结逆传，可能是正常人群中室房逆传的真实反映。有室房逆传患者的房室结前传功能优于无室房逆传者，也优于其本身的逆传功能。房室结逆传冲动进入心房可能存在两条不同的通路。     

重离子束辐照诱变及高通量筛选金霉素高产菌株

应用不同剂量12C+6重离子束对金霉素链霉菌出发菌株B9-34-125进行辐照诱变,并应用96和48孔板高通量筛选金霉素高产菌株。结果表明：当重离子束12C+6离子的辐照剂量为60Gy时,对金霉素链霉菌的诱变效果显著,筛选出5株优势菌株,其中Z-1452菌株摇瓶发酵效价较对照提高14.4%,60m3发酵效价较对照提高5.7%,产量提高了2.6%。     

鼻咽内窥镜对咽鼓管咽口的形态学观察

目的对正常成人咽鼓管咽口进行观察，找出可以描述咽鼓管咽口的量化指标，为进一步研究奠定基础。方法利用鼻咽内窥镜观察并录像记录５８例正常成人咽鼓管咽口。分别用０°，３０°，６０°，９０°内窥镜观察鼻咽部和咽鼓管咽口。结果经比较认为，６０°内窥镜是观察咽口及鼻咽侧壁的最佳角度。该角度镜面与咽口平面平行，观察咽口最直观，对于咽口处于开放状态时，此角度能窥及管内情况。而且通过镜面的旋转和上下左右移动，可以清楚地观察圆枕、前唇、提肌隆突、咽隐窝和下鼻甲后端在鼻腔侧壁的附着处。０°镜观察鼻咽顶壁和后壁视野清晰。结论提出：①提肌隆突在咽口内形成的弓形皱襞的前缘与鼻腔外侧壁的夹角，②提肌隆突后缘与咽口前壁的夹角，③圆枕与咽口前唇的相对厚度，④咽口静止时的开放状态及⑤吞咽时咽口的运动方式作为描述咽口形态的量化指标，并以此为根据，将咽口形态分为椭圆形２．６％，喇叭形１９．８％，三角形６８．１％，缝隙形９．５％。本研究为计算机辅助图像分析咽鼓管咽口形态奠定基础     

Umbilical hernias treatment by the "stamp mesh technique"

We describe an original technique for umbilical hernia repair ("stamps mesh technique") during which no umbilical ring widening is carried out. A non-absorbable mesh is positioned in the preperitoneal space.     

Transvaginal Cholecystectomy without Abdominal Ports

Background:

Pioneers in natural orifice transvaginal cholecystectomy are in search of an approach that uses less percutaneous assistance. The approach must be safe and affordable. The authors present a successful cholecystectomy using a technique of transvaginal operative laparoscopy with no abdominal ports.

Methods:

A 24-year-old female patient with gallbladder lithiasis underwent a natural orifice cholecystectomy with only one transvaginal 12-mm port, using a laparoscope with a working channel. We used laparoscopic instruments 5 mm in diameter by 43cm in length (including a needle holder, Maryland dissector clamp, spatula, hook, suction cannula, and clip applier) and assistance with percutaneous marionette leashes.

Results:

The patient stayed in the hospital for 24 hours and was discharged without pain and without scars.

Conclusion:

Transvaginal cholecystectomy performed using an operative laparoscope with a working channel is possible in select cases. This technique requires no abdominal ports and is an alternative to culdolaparoscopy or hybrid transvaginal procedures with flexible endoscopes.     

Use of an ultrasound blood-mimicking fluid for Doppler investigations of turbulence in vitro

Turbulence is an important factor in the assessment of stenotic disease and a possible causative mechanism for thromboembolism. Previous Doppler studies of turbulence have typically used whole-blood preparations or suspensions of erythrocytes. Recently, a water-glycerol based blood-mimicking fluid (BMF) has been developed for use in Doppler ultrasound studies. This fluid has desirable ultrasound properties but it has not previously been described during in vitro investigations of turbulence intensity. We report on investigations of grid-generated and constrained-jet turbulence in an in vitro test system. The BMF was found to generate significant levels of turbulence during steady flow at physiological flow rates, producing turbulent patterns in the distal region that were consistent with previous studies. Turbulence intensity increased significantly with flow rate (p < 0.005) for both the constrained jet and the constrained grid. Based on our observations, we conclude that a water-glycerol based BMF provides a suitable working fluid during in vitro investigations of turbulence using Doppler ultrasound.     

张仲景特殊给药途径初探

就《伤寒论》和《金匮要略》两书中除了口服给药以外的其它孔窍给药方法进行了全面总结,结果勾勒出舌窍给药、齿龈给药、鼻窍给药、耳窍给药、前阴给药、肛门给药、脐窍给药、毛窍给药等八种特殊孔窍给药途径。文中对于每法的条文出处、具体操作和药物吸收原理进行了较详尽的探析。     

Doppler ultrasound in orifice flow. In vitro studies of the relationship between pressure difference and fluid velocity

The validity of an orifice equation (Torricelli's law) which expresses a simple relationship between the pressure difference across an orifice and the maximum fluid velocity in the orifice was tested in vitro. An aqueous suspension of barium sulfate particles with a polymer added to attain variations in viscosity, was forced through orifices which ranged in diameter from 0.4 to 4.7 mm. The pressure difference across the orifice was determined with a transducer and the maximum fluid velocity in the orifice was determined with Doppler ultrasound. Tests were performed at Reynolds numbers, fluid viscosities, and pressure differences that spanned the following ranges: 400-25,000, 1-5 cP, and 3-100 mmHg, respectively. At pressure differences larger than 3 mmHg and fluid viscosity 3 cP (approximate viscosity of in vivo blood), Torricelli's law was demonstrated to be valid for orifice diameters larger than 1.6 mm. The validity of the law was found to be relatively insensitive to variations in orifice length.     

Hydrodynamic Investigation of Mechanical Bileaflet Valves

For hydrodynamic comparison, 11 mechanical bileaflet valves have been perfused in a mock circulation system under pulsatile flow conditions. Six St. Jude Medical valves with different sizes from No. 21 to No. 31 and five Duromedics prostheses with corresponding sizes from No. 21 to No. 29 have been investigated. Flow, pressure, and orifice area were measured, while cardiac output was varied between 2 and 6 L/min. Insufficiency (I), maximal orifice area (Amax), mean orifice area (A), discharge coefficient (CD), performance index (PI), and efficiency index (EI) were determined. The St. Jude Medical valves show higher values of orifice area when compared with the Duromedics valves. For smaller valve sizes up to No. 25, the values of the orifice area are similar. The Duromedics valves show much lower values of insufficiency; thus, for small valve sizes, the Duromedics prosthesis seems to be superior. For larger valve sizes (No. 27, No. 29, and No. 31), a decision has to be made whether higher insufficiency and higher orifice area of the St. Jude Medical valve or lower insufficiency with lower orifice area is more acceptable.