不同类型西洋参花、叶的电镜比较观察

采用扫描电镜对单、双茎西洋参的花粉、叶进行了观察,证明两者在花粉壁的雕纹、叶表皮角质沉积纹理的超微结构上存在着明显的差异。     

下蹲运动与高眼压关系及其动态观察

观察１８例３２眼下蹲运动与高眼压的关系，分为下蹲１２０次，１００次及８０次三且，每组分别观察１０眼、１１眼及１１眼，结果各组运动后眼压均见下降，平均为１．０２７±０．４８６ｋＰａ，１．３５５±０．７７０ｋＰａ及１．３２５±０．４２２ｋＰａ，运动前后有非常显著性差异，但各组之间差异不显著。同时观察３小时内眼压动态变化，下蹲１２０次组眼压下降维持时间最长，在运动后３小时与运动前眼压比较及与其余两组第３     

着色真菌蟾蜍分离株小鼠致病试验研究

目的：观察着色真菌蟾蜍分离株的致病性。方法：抽样取着色真菌蟾蜍分离株与标准人分离株对照，制成菌悬液，做小鼠腹腔接种，观察接种后小鼠的外观表现，做菌种逆培养和观察内脏病理变化。结果：蟾蜍分离株卡氏枝孢霉、疣状瓶霉、裴氏着色霉和甄氏外瓶霉与病人分离株一样，在接种28天后，均可从小鼠脏器逆培养出接种的菌种，并引起内脏病变，形成结核样肉芽肿，肉芽肿内均可查见棕黄色硬壳小体。而瓶霉和外瓶霉属菌种逆培养结果均阴性。结论：从野生蟾蜍分离出的卡氏枝孢霉、疣状瓶霉，裴氏着色霉和甄氏外瓶霉与病人分离株一样，对小鼠有致病性，故可能是人着色芽生菌病的致病菌。     

Percutaneous transhepatic stenting by wallstents of portal vein and bile duct stenoses caused by immunoblastic sarcoma in a liver transplantation

Posttransplant lymphoproliferative disorders are infrequent tumors related to chronic immunosuppressive therapy. We present a liver transplant recipient who developed such a tumor in the porta hepatis that provoked obstruction of the entire portal triad. Treatment consisted of systemic chemotherapy, percutaneous dilatation, and placement of Wallstent endoprostheses across both biliary and portal vein stenoses. The patient died 3 weeks later of pneumonia and sepsis. At necropsy, the tumor was completely necrosed and the prostheses in both the common bile duct and the portal vein were patent.     

健脾降脂颗粒中绿原酸的含量测定

目的　研究健脾降脂颗粒中绿原酸的含量测定方法。方法　采用高效液相法。色谱柱YWGC18(2 5 0mm× 4 6mm ,10 μm) ,室温 ,10 %乙腈─冰醋酸 (5∶0 1)为流动相 ,流速为 1mL/min ,检测波长 32 9nm。结果　绿原酸在 0 0 2 0 8～ 0 10 4 μg范围内呈线性关系 (r =0 9994 ,n =5 ) ,平均加样回收率为 96 2 3% ,RSD为 0 798%。结论　本方法准确、可行 ,可用于健脾降脂颗粒的质量控制     

Serotonin 5- HT (2C) receptor knockout mice: autoradiographic analysis of multiple serotonin receptors.

Quantitative receptor autoradiography was used to study possible alterations of the densities of multiple serotonin (5-HT) receptor subtypes and of serotonin transporter in the brain of 5-HT(2C) receptor knockout mice. The radioligands employed were [(3)H]citalopram, [(3)H]WAY100,635, [(3)H]8-OH-DPAT, [(3)H]GR125743, [(3)H]sumatriptan, [(3)H]MDL100,907, [(125)I](+/-)DOI, [(3)H]mesulergine, [(3)H]5-HT, [(3)H]GR113808, and [(3)H]5-CT. As expected, radioligands that label 5-HT(2C) receptors showed a complete absence of labeling in mutant mice choroid plexus and significantly reduced densities in other brain regions expressing 5-HT(2C) receptors. With the rest of the radioligands, no significant alterations in the densities of labeled sites were found in any brain region. In situ hybridization showed no changes in 5-HT(2A) receptor and serotonin transporter mRNA levels, whereas 5-HT(2C) receptor mRNA levels were reduced in certain brain regions. The present results indicate that the mouse serotonergic system does not exhibit compensatory up- or down-regulation of the majority of its components (serotonin transporter and most 5-HT receptor subtypes) in response to the absence of 5-HT(2C) receptors.     

血浆巨细胞病毒多聚酶链反应检测用于指导干预性治疗

目的：分析用血浆巨细胞病毒（cytomegalovirus,CMV)多聚酶链反应（plymerase chain reaction,PCR)检测结果指导抗CMV干预性治疗的临床意义。方法：1999年8月至2001年7月行异基因造血干细胞移植（hematopoietic stem cell transplantation,HSCT)的所有患者自预处理开始，常规用PCR法检测血浆的CMV－DNA（采用华美公司生产的巨细胞病毒4℃ PCR检测试剂盒），每周1次。其中尚无CMV病的临床表现而检测到血浆CMV阳性的患者89例。随机选取52例阳性患者给予干预性治疗。将上述89例患者分为3组（分别为停止治疗时血浆CMV－PCR转阴组、停止治疗时未转阴组、血浆CMV阳性未治疗组）比较各组CMV病的发生率。CMV病的发生率采用Kaplan-Meier曲线表示，曲线间的比较用Log-Rank（曲线无交叉）或Breslow（曲线交叉）检验，某时点率的比较采用RXC列联表或χ^2检验。结果：100d内CMV病的发生率，在治疗后血浆CMV－PCR由阳性转为阴性组为10．26％，治疗结束时血浆CMV－PCR仍为阳性组为66.67%，血浆CMV－PCR阳性未治疗组为36．24％（P＝0.0000)。上述3组中任两组移植后100d CMV病的发生率差异均有显著性。移植后1年时上述3例CMV病累积发生率分别为30.65%、75.00%、42.95%(P=0.0009)，治疗未转阴组与治疗转阴组和阳性未治疗组相比，CMV病的发生率明显升高。结论：血浆CMV－PCR检测结果用来指导干预性治疗有一定临床意义。干预性治疗后血浆CMV－DNA仍未转阴者，应考虑换药或联合用药治疗。     

B90催化剂上丁烯氧化脱氢的反应动力学─一一种简便的建立化学动力学方程的方法

采用简便的建立化学反应动力学方程的方法，研究了Ｂ９０催化剂上丁烯氧化脱氢制丁二烯反应的动力学，即先在一较低温度下，用微分法拟合得到化学反应动力学方程中的浓度项，然后改变反应温度，求算不同温度下的反应速率常数。采用这个简便方法，只需较少的实验，即可求得该反应体系中的丁烯转化速率方程式。     

Mitochondrial DNA variability detected in a single wheat regenerant involves a rare recombination event across a short repeat

The mitochondrial genome of the selfed progeny of a plant regenerated from long-term somatic tissue culture displays specific structural rearrangements characterized by the appearance of novel restriction fragments. A mitochondrial DNA library was constructed from this selfed progeny in the SalI site of cosmid pHC79 and the novel fragments were subsequently studied. They were shown to arise from reciprocal recombination events involving DNA sequences present in the parental plant. The regions of recombination were sequenced and the nucleotide sequences were aligned with those of the presumptive parental fragments. We characterized an imperfect short repeated DNA sequence, 242 bp long, within which a 7-bb DNA repeat could act as a region of recombination. The use of PCR technology allowed us to show that these fragments were present in both parental plants and tissue cultures as low-abundance sequence arrangements.     

Transesophageal echocardiography-guided cardioversion of atrial fibrillation. Selection of a low-risk group for immediate cardioversion.

INTRODUCTION: In patients (pts) with atrial fibrillation (AF) of more than 48 hours' duration, electrical cardioversion (ECV) should only be performed after 3 weeks of effective anticoagulation. Transesophageal echocardiography (TEE) allows earlier ECV; however, despite exclusion of thrombi in the atrium and left atrial appendage (LAA), cases of thromboembolism related to ECV have been documented in AF. To define a low-risk group for cardioversion without previous anticoagulation, pts were selected for immediate ECV if no thrombi or dynamic spontaneous echo contrast (auto-contrast) were found after TEE and if LAA velocity was more than 0.25 m/sec. METHODS AND RESULTS: We performed TEE in 31 consecutive pts referred for ECV for AF of more than 48 hours' duration and without previous anticoagulation. After TEE the pts eligible for immediate ECV began anticoagulation with low molecular weight heparin (enoxaparin), subcutaneously in therapeutic doses, together with warfarin immediately before cardioversion. Enoxaparin was continued until an INR of over 2 was reached. Based on the TEE findings, the pts were divided in 2 groups: immediate ECV, group A, 20 pts with a mean age of 62 +/- 13 years, 6 female; and conventional therapy with warfarin before ECV, group B, 11 pts, mean age of 67 +/- 10 years (p < 0.05), 2 female. None of the pts in either group had mitral stenosis or previous episodes of thromboembolism. The mean transverse diameter of the left atrium in the 31 pts was 47 +/- 4.5 mm, without statistically significant differences between the 2 groups. Of the 11 pts in group B, 3 had a thrombus in the LAA, 6 dynamic spontaneous echo contrast and the remainder LAA velocities of less than 0.25 m/sec. ECV was achieved in all the pts, with no complications. Oral anticoagulation was maintained for at least a month. At one month, sinus rhythm was maintained in 75% of group A and 45% of group B (p < 0.01). CONCLUSION: In pts with AF of more than 48 hours' duration and no previous history of thromboembolism, the use of our exclusion criteria during TEE enabled stratification of a low-risk population for immediate ECV, which was accomplished effectively and safely in 2/3 of the pts. This strategy is associated with early symptomatic improvement, and may contribute to maintenance of sinus rhythm after one month, which was significantly better than in the pts who had prolonged therapy with warfarin before ECV, despite the differences found in age and left ventricular function.