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81.
“人民,是创造历史的真正动力”——壮哉斯言;“真理,只掌握在少数人手中”——诚哉斯言。尽管发生在苏北宿迁的这场席卷城乡的改革,绝不可能只由少数精英分子独立完成,但最初的推动力,是全民意志的厚积薄发?是少数精英的灵光一闪?抑或是一场上级授权、政府定规、全民参与的社会实验? 相似文献
82.
Rats were exposed to daily 3-hr schedule-induced polydipsia sessions (fixed-time 1-min food-pellet delivery) with two drinking fluids available: cocaine solution and water. Fluid position was alternated daily. Polydipsia occurred mostly from a preferred-side spout (position preference) until cocaine solution concentration was increased to between 0.52 and 1.04 mg/ml and animals drank mostly water. Within a lower concentration range (0.28-0.6 mg/ml) maximum session cocaine intakes ranged from 54.3 to 120.1 mg/kg. Postsession serum cocaine levels were about 200 ng/ml. At individually chosen cocaine solution concentrations, the addition of saccharin to the solution did not increase cocaine intake, but a compound solution (saccharin plus glucose) did. With progressive dilution of the compound vehicle, an almost complete preference for cocaine solution was maintained. But with a return to water as the vehicle, animals reverted to a position preference after a few sessions, although one maintained a clear cocaine preference. Schedule-induced polydipsia produced chronic, oral self-administration of cocaine resulting in pharmacologically significant intakes and serum levels. 相似文献
83.
84.
Razeq Shetab Stuart H. Cohen Thomas Prindiville Yajarayma J. Tang Mary Cantrell Darush Rahmani Joseph Silva Jr. 《Journal of clinical microbiology》1998,36(6):1729-1732
Bacteroides fragilis constitutes about 1% of the bacterial flora in intestines of normal humans. Enterotoxigenic strains of B. fragilis have been associated with diarrheal diseases in humans and animals. The enterotoxin produced by these isolates induces fluid changes in ligated intestinal loops and an in vitro cytotoxic response in HT-29 cells. We developed a nested PCR to detect the enterotoxin gene of B. fragilis in stool specimens. After DNA extraction, a 367-bp fragment was amplified with two outer primers. The amplicon from this reaction was subjected to a second round of amplification with a set of internal primers. With these inner primers, a 290-bp DNA fragment was obtained which was confirmed as part of the B. fragilis enterotoxin gene by Southern blotting with a nonradioactive internal probe and a chemiluminescence system. By this approach, B. fragilis enterotoxin gene sequences were detected in eight known enterotoxigenic human isolates and nine enterotoxigenic horse isolates. No amplification products were obtained from DNA extracted from 28 nonenterotoxigenic B. fragilis isolates or B. distasonis, B. thetaiotaomicron, B. uniformis, B. ovatus, Escherichia coli, or Clostridium difficile. The sensitivity of this assay allowed us to detect as little as 1 pg of enterotoxin DNA sequences or 100 to 1,000 cells of enterotoxigenic B. fragilis/g of stool. Enterotoxin production of all isolates was confirmed in vitro in HT-29 cells. A 100% correlation was obtained between enterotoxin detection by cytotoxin assay and the nested PCR assay. This rapid and sensitive assay can be used to identify enterotoxigenic B. fragilis and may be used clinically to determine the role of B. fragilis in diarrheal diseases. 相似文献
85.
86.
汕头卫生检疫局空港处对汕头航空口岸—宗入境二级货包的监测过程及对有关运输工作人员作了放射知识问卷调查。从中发现。运输单位货物存放设施落后。有关工作人员放射卫生知识欠缺,对放射污染可能造成的危害缺乏正确的认识。为此,笔者提出了自己的看法,以期对放射监测工作的进一步完善提供参考。 相似文献
87.
纤维支气管镜胸膜腔检查对原因不明胸腔积液的诊断价值 总被引:2,自引:0,他引:2
为评价纤维支所管镜行胸膜检查在诊断原因不明胸腔积液中的价值,用纤维支气管镜对10例原因不明的胸腔积液患者进行胸腔检查。结果9例2检查后明确了病因,且无并发症,提示该法对于不明胸腔积液的诊断是一种阳性率高、安全、简便的检查方法。 相似文献
88.
综述了有机锗抗肿瘤药物,对β-羧乙基锗倍半氧化物(Ge-132)和螺锗在肿瘤学中的作用以及抗癌效应机制作出评价。自80年代起至今,又有含硫杂、柠檬酸、氨基酸、苯基的锗化合物,以及锗酵母、含锗中草药等被先后合成出来。在几类具有生物活性的有机锗化合物中,仍首推Ge-132,螺锗及其衍生物为低毒有效抗肿瘤候选药物,然而对于锗导致的毒性及其机理仍需进一步加以探讨。 相似文献
89.
K. Wilhelmsen D. Mirel K. Marder M. Bernstein A. Naini S. M. Leal L. J. Cote M.-X. Tang G. Freyer J. Graziano R. Mayeux 《Annals of neurology》1997,41(6):813-817
The cytochrome P450 mono-oxygenase gene, CYP2D6 on chromosome 22q13 (ch22q13), has been inconsistently associated with Parkinson's disease. Associations with CYP2D6 have either been absent altogether or have involved more than one polymorphism, many of which have the same metabolic effect on gene expression. We examined the association between CYP2D6 polymorphisms and Parkinson's disease in a case-control study and included 10 polymorphic dinucleotide repeat markers linked to CYP2D6 to determine whether the association was present or due to linkage disequilibrium. There was no association between any polymorphism of CYP2D6 and Parkinson's disease, but two of 10 dinucleotide repeat markers linked to CYP2D6 were associated with the disease. These results provide evidence to suggest that there may be an unidentified locus for susceptibility to Parkinson's disease that is in linkage disequilibrium with dinucleotide repeat markers mapping near CYP2D6 on ch22q13. 相似文献
90.
Microbiologic and clinical value of primary broth cultures of wound specimens collected with swabs. 总被引:1,自引:1,他引:0
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In order to assess the microbiologic and clinical value of primary broth culture of wound specimens collected with swabs and submitted to the laboratory in transport medium, we compared the results of primary agar culture with the results of a corresponding primary broth culture for 344 aerobic specimens and 176 anaerobic specimens. While 8.7% (45 of 520) of the specimens yielded organisms from the primary broth culture that were not recovered from the corresponding primary agar culture, only 5.0% (26 of 520) of the specimens yielded organisms from the primary broth culture other than Staphylococcus epidermidis, viridans group streptococci, and Corynebacterium spp. Moreover, the primary broth culture of only 0.6% (3 of 520) of the specimens yielded organisms not recovered from the primary agar culture that caused a change in the therapy of the patient. Our conclusion is that primary broth cultures are unnecessary for the processing of wound specimens properly collected with swabs. 相似文献