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81.
取因职业而接触乙烯类或苯类的孕妇静脉血和他们新生儿脐带血进行SCE和MN测定。发现接触乙烯类或苯类的母血SCE(8.55±0.84,9.44±1.12)均高于对照组(7.68±1.40),他们新生儿脐带血SCE(8.94±1.43,8.75±0.88)也高于对照组(6.71±1.27)。接触乙烯类和苯类的母血微核率(0.833‰,0.727‰),高于对照组(0.267‰),他们新生儿脐血微核率(0.75‰,0.818‰)也高于对照组(0.267‰)。我们还发现母亲孕期被动吸烟增强了这两类诱变剂对他们后代的遗传毒性。  相似文献   
82.
妊娠合并登革热35例临床分析   总被引:1,自引:0,他引:1  
目的 探讨登革热对妊娠的影响。方法 对35例妊娠合并登革热进行回顾性分析。结果 35例患有27例出现不正常分娩及产后大出血,有22例出现流产、死胎、早产及畸胎。结论 妊娠合并登革热在妊娠早期可出现流产或死胎,中期可引起早产,晚期可出现产后大出血。  相似文献   
83.
行腹膜外剖宫产术时,在侧脐韧带与中脐韧带之间进行操作,不切断腹壁任何韧带,用撕拉、钝性剥离的方法分离膀胱与腹膜,子宫切口连续缝合两层,并将宫颈前筋膜与子宫切口浅层一并连续缝合.该方法不仅缩短了手术时间,避免了新生儿Apgar's低评分、新生儿窒息的发生,而且维持了腹壁结构的完整性,可进一步降低术后各种近、远期并发症的发生率.  相似文献   
84.
Xiao  Bihuan  Jiang  Yuan  Wang  Bin  Hu  Yang  Sun  Yan  Wu  Yan  Qiao  Shuai 《Lasers in medical science》2021,36(6):1261-1266
Lasers in Medical Science - Large-scale long-term retrospective study of noninsulated microneedle radiofrequency treatment on neck rejuvenation is lacking. We conducted a 3-year retrospective...  相似文献   
85.
86.
慢性萎缩性胃炎(CAG)是消化系统常见的慢性疾病,被认为是胃癌癌前病变,严重危害人类健康。如何有效促进胃黏膜的修复、抑制腺体的萎缩、阻断癌变是临床研究的热点。目前西医尚缺乏特效的治疗手段,近年来,大量研究结果表明,中医外治法在治疗CAG方面取得了显著成果,且具有简、便、效、廉等优势,深受患者青睐。现查阅近年来包括针刺法、灸法及贴敷法等在内的常用中医外治法治疗CAG的相关文献并进行综述,以期为临床治疗该病提供参考。  相似文献   
87.
The effects of microiontophoretically applied cocaine, desipramine (DES), sulpiride (SUL), methysergide (METH), and naloxone (NAL) on the responses of physiologically identified single neurons in the habenula (Hab) and parafasciculus thalami nucleus (PF) were examined in rats. Three cell types were identified in both nuclei on the basis of the responses obtained following noxious stimulation that were classified as "nociceptive-on," "nociceptive-off," and "nonnociceptive" cells. Administration of cocaine generally resulted in a decrease in the firing rate of nociceptive-on and nonnociceptive neurons in both Hab and PF. In contrast, cocaine generally induced an excitation in the baseline firing of the nociceptive-off cells. Cocaine application concomitant with noxious stimulation prevented the evoked responses of the nociceptive-on and the nociceptive-off cells. DES, when applied alone, was found to induce excitation in neuronal discharge of all three cell types in both sites. Combined application of cocaine with DES resulted in no observable change in discharge frequency for the nociceptive-on and nonnociceptive cells, while inducing an additive excitatory effect on the nociceptive-off cells. SUL, in contrast, induced no observable effect on baseline firing when given alone, yet consistently antagonized cocaine-induced effects on all three cell types. Finally, METH and NAL induced no effects on baseline firing or cocaine-induced modifications in neuronal discharge frequency.  相似文献   
88.
A system is described for assembling infectious bacteriophage phi 6 nucleocapsids in vitro. Procapsids encoded by cDNA copies of genomic segment L in Escherichia coli were used to package and replicate viral RNA segments. The resulting filled particles were shown to be capable of infecting host cell spheroplasts after incubation with purified nucleocapsid shell protein P8. The infected spheroplasts yielded infectious virions. A modified cDNA-derived RNA segment was inserted into virions by this method. The resulting infectious virions contained the same 4-base-pair deletion as the modified cDNA. These findings support the contention that the preformed procapsids are the "machine" that replicates the phi 6 genome, by showing that the cDNA-derived procapsids are competent to package and replicate RNA properly.  相似文献   
89.
In order to research the states of dentine surface and dentine surface primed with coupling agent, we used microscope, transmission electron microscope (TEM) and solid fluorescence method. Observed under microscope, patterning of dentinal tubules and their poles was very explicit; through the view of interface between coupling agent adsorbed and human dentine powder by TEM, it was revealed that the coupling agent was adsorbed onto the dentine surface as if it "grew out" of the dentine surface; through examination of interface between the coupling agent adsorbed and dentine surface by fluorescence spectrum, which differed from that of the coupling agent or dentine surface, i.e., this fluorescence spectrum of interface changed obviously (red shift). This phenomenon indicated that there was a chemical reaction occurring between tooth surface and adsorbed coupling agent. Therefore we can conclude that the three examinations are necessary to provide the argument for establishment of chemical bonding mechanism between dentine and coupling agent.  相似文献   
90.
Summary For determination of trace Se we used high-pressure wet digester to pretreat the specimens obtained from the human body. This method is very effective in preventing loss of Se by volatilization which often occurs in the sample pretreatment. We studied the method of using anodic stripping voltammetry at gold-disc electrode to measure the trace Se present in the human body and found it to be the optimal procedure. The detection limitation was about 2x10−8 g/L, the recovery rate of Se about 96.6±6,7 % , and the coefficient of variation CV = 7.0%.  相似文献   
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