外科手术中产生的烟气:仅仅是大量的热空气吗?

外科医生和手术室人员经常接触手术设备产生的烟气,病人也会暴露于烟气中,特别是腹腔镜手术中产生的烟气滞留于腹腔内这一密闭空间并被吸收.这些烟气是一种与香烟烟气相似的毒性物质,然而对这种毒性物质的影响还未引起足够重视.应该采取必要措施尽可能减少手术中烟气的不良影响.     

取代四氢异喹啉衍生物的合成及其生物活性

粉防己碱有钙拮抗作用,临床试用于治疗高血压,其裂解产物钙拮抗作用降低,但有α-肾上腺素能受体拮抗作用,本文以裂解物为先导化合物设计合成了两类取代的四氢异喹啉衍生物Ⅲ及Ⅳ。初步药理试验表明:大部分化合物有α-肾上腺素能受体拮抗作用,少数化合物钙拮抗活性有所增强,其中Ⅲ_15,19对正常麻醉大鼠有一定的降压作用、Ⅳ_17,19对实验性动物心律失常有明显的保护作用。部分化合物量化计算表明:化合物与α₁-受体作用方式可能是形成电荷转移复合物。     

Hemorrhagic and nonhemorrhagic brain lesions: evaluation with 0.35-T fast MR imaging

Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study.     

Typing of clinical herpes simplex virus isolates with mouse monoclonal antibodies to herpes simplex virus types 1 and 2: comparison with type-specific rabbit antisera and restriction endonuclease analysis of viral DNA

A total of 122 clinical isolates of herpes simplex virus (HSV) from 107 patients were typed by using an indirect immunoperoxidase technique with commercially available type-specific rabbit antisera, recently developed mouse monoclonal antibodies to HSV types 1 and 2, and restriction endonuclease analysis of viral DNA. With the commercially available type-specific rabbit antisera, 34% of clinical HSV isolates were of indeterminate type; 63% of them were typed as HSV type 1 and 37% as HSV type 2 by using monoclonal antibody and restriction enzyme typing systems. Typing by immunofluorescence assay with the monoclonal antibodies gave identical results to those obtained by restriction enzyme analysis. Simultaneous infection with both HSV types was demonstrated by monoclonal antibody typing in five isolates from three patients. These findings were subsequently confirmed by plaque purification and restriction endonuclease analysis of viral DNA. Monoclonal antibodies were as sensitive as restriction enzyme analysis for the typing of clinical HSV isolates. Because of their simplicity, they are more amenable to use in clinical laboratories than is restriction endonuclease analysis.     

Genetic control of natural immunity to ecotropic mouse leukemia viruses: production of endogenous immunogen.

Mice of the AKR and C57L strains naturally produced low titers of antibody against ecotropic murine leukemia viruses (MuLV). The F1 hybrid of these strains produced anti-MuLV antibody in higher titer than mice of either of the parental strains. Progeny of the genetic backcross C57L X (AKR X C57L)F1 segregated for the production of infectious ecotropic MuLV (according to the Akv-1 and Akv-2 loci) and for the production of antibody against MuLV. All mice that contained infectious MuLV produced anti-MuLV antibodies. Thus, the persistent production of high-titered MuLV in these mice did not result in immunological tolerance towards viral antigens. In contrast, mice that did not contain infectious MuLV could be separated into antibody-producing and -nonproducing classes. The absence of detectable antibody to MuLV in an individual mouse was invariably associated with a virus-free phenotype. Antibody against MuLV reacted primarily with p15 and gp70 proteins of the viral envelope. It was concluded that overt production of endogenous ecotropic MuLV served as a major immunogenic stimulus for the production of anti-MuLV antibody in these mice.     

Oncornaviruses produced by murine leukemia cells in culture.

Leukemia cells from mice of the AKR and C58 strains produced leukemia viruses (MuLV) in culture that failed to induce syncytia in the XC plaque assay (XC^?), were poorly infectious for mouse embryo fibroblasts, and yielded low levels of infectious progeny upon the establishment of infection. In host range analysis the majority of these viruses were N-ecotropic, although one leukemia cell line also produced xenotropic MuLV. Viral isolates from five different leukemia cell lines were oncogenic upon inoculation into newborn AKR mice. In contrast, viruses that occurred in high titer in the tissues and sera of normal AKR mice were not oncogenic in vivo and in culture they efficiently induced (with N-ecotropism) syncytia in the XC plaque assay (XC⁺). These findings demonstrate that the transforming agent for spontaneous leukemogenesis differs in biological properties from the endogenous MuLV that is commonly observed in mice of high leukemic strains.     

大鼠舌咽和迷走神经感觉神经节内P2X_2、P2X_3受体与calretinin和IB4结合位点的共存

应用免疫组织化学荧光三标方法结合激光共聚焦显微镜技术研究了大鼠舌咽和神经迷走神经感觉神经节内ATP受体P2X2、P2X3与calretinin、植物凝集素(IB4)结合位点的共存。结果显示:舌咽和迷走神经感觉神经节内可见大量P2X2、P2X3阳性的神经元胞体和纤维,P2X2受体阳性细胞多为大、中、小型神经元,P2X3阳性细胞多为中、小型神经元;可见较多的P2X2/IB4及P2X3/IB4双标神经元。有(91.1±4.7)%(结状神经节)、(78.8±2.4)%(岩神经节)、(76.8±2.7)%(颈静脉神经节)为P2X2阳性细胞;(77.0±3.2)%(结状神经节)、(91.2±3.9)%(岩神经节)、(78.4±3.6)%(颈静脉神经节)的P2X3阳性细胞结合IB4;有8.9±1.6%(结状神经节)、7.7±1.4%(岩神经节)、9.1±1.1%(颈静脉神经节)的P2X2阳性细胞呈calretinin阳性;三神经节内均观察到少量P2X2/calretinin/IB4三标细胞。P2X3/calretinin双标或P2X3/calretinin/IB4三标神经元数量较少。这些结果提示,舌咽和迷走神经感觉神经节内ATP受体P2X2、P2X3与IB4结合位点存在广泛的共存,部分P2X2受体与calretinin存在着共存。