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1.
Haaga  JR; Beale  SM 《Radiology》1986,161(3):829-830
By injecting small amounts of CO2 through a needle, one can move bowel or bladder from the intended path of instruments during interventional procedures. The technique worked well in six of seven cases in the pelvis and retroperitoneum; it was not effective in the mediastinum or midabdomen (n = 6).  相似文献   
2.
Stomatococcus mucilaginosus was isolated from the blood of a patient with endocarditis and a past history of drug abuse and aortic valve replacement. At autopsy, Gram stain of the aortic valve revealed gram-positive cocci. Our isolate was atypical for S. mucilaginosus in that colonies were nonmucoid and nonadherent to agar surfaces. Cellular capsules were demonstrated by light and electron microscopy. Phenotypic characteristics identified by conventional methods as well as profile numbers obtained by using two commercial identification systems for staphylococci, the API Staph-Ident and the dms Staph Trac, are presented. Practical tests that differentiate S. mucilaginosus from the genera Micrococcus and Staphylococcus include growth on nutrient agar containing salt and lysostaphin susceptibility. Additional tests that helped differentiate our isolate from group D streptococci included hydrolysis of L-pyrrolidonyl-beta-naphthylamide and streptococcal serogrouping.  相似文献   
3.
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.  相似文献   
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The aromatic amine ortho-toluidine has been recognized by IARC as an animal carcinogen for the past decade. Three recent epidemiological studies of worker populations have now implicated this chemical as a human bladder carcinogen. In a study by E. Ward, A. Carpenter, S. Markowitz, D. Roberts, and W. Halperin ((1991), J. Natl. Cancer Inst. 83, 501–506), workers definitely exposed to ortho-toluidine for at least 10 years experienced a Standardized Incidence Ratio (SIR) of 27.2 (90% CI = 11.8–53.7). The other major exposure was to aniline, which significant epidemiological studies have failed to confirm as a human carcinogen. In retrospect, studies by G. F. Rubino, G. Scansetti, G. Piolatto ((1982) Environ. Res. 27, 241–254) and M. J. Stasik ((1988) Int. Arch. Occup. Environ. Health 60, 21–24) also support the hypothesis that ortho-toluidine is a human bladder carcinogen. Animal studies of both ortho-toluidine and its possible confounders in these epidemiological investigations further confirm this hypothesis. When evaluated in a suitably comprehensive way, according to the traditional standards for assessing causality outlined by A. B. Hill ((1977) A Short Textbook of Medical Statistics, pp. 288–294, Lippincott, Philadelphia) the evidence that ortho-toluidine causes human bladder cancer has become much more conclusive. In this case, animal tests have proven a good predictor of human carcinogenicity.  相似文献   
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The experience of the Charity Hospital surgeons in dealing with desmoid tumors is examined retrospectively over a 30-year period. Sixteen cases are presented. A 33 per cent rate of recurrence was noted despite excisions with margins free of tumor in each instance. In accordance with chi-square analysis, unequivocal statistical significance is given to the fact that women who have been pregnant are more likely to have abdominal than extraabdominal desmoid tumors. It was also found to be significant that parous women in whom desmoids develop are more likely to have the tumor within 10 years of their last pregnancy.  相似文献   
10.
The influence of family history on DNA repair synthesis, unscheduledDNA synthesis (UDS), was assessed in volunteers with or withouta family history of cancer. UDS, following treatment of mononuclearleukocytes with N-acetoxy-2-acetylaminofluorene, was measuredas the incorporation of [3H] into DNA in the presence of hydroxyurea.The positive family history group (n=71) had an average of 2.4first-degree relatives with cancer, defined as any major cancer,excluding skin cancer: 31 participants reported that canceroccurred in both their parents. The ‘no family history’comparison group (n=29) had no family history of cancer throughthe second degree. There was a significant reduction in UDSin cells from individuals with family history, compared to thosewith no family history (P>0.002). This relationship was notexplained by factors known to influence UDS, such as age, smokingor hypertension. We conclude that reduced UDS in mononuclearleukocytes is associated with a family history of any majorcancer, and is not confined to a history of cancer of any singleorgan site. This conclusion is further supported by the observationthat individuals (n=13) with parents who had an earlier onsetof cancer (<60 years) also had a significantly lower DNArepair synthesis than those (n=18) whose parents had later diagnosisof cancer (>60 years).  相似文献   
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