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E MOLKE JENSEN K. A. THIESSEN AA. CHRISTENSEN 《Acta anaesthesiologica Scandinavica》1986,30(2):109-110
The effect of 4 mg oral naloxone on preoperative gastric volume and pH of gastric aspirate was studied in a double-blind, randomized study. Twenty patients received 10 ml of naloxone (4 mg) mixed with 10 ml of orange juice, and 20 patients received 10 ml of isotonic saline mixed with 10 ml of orange juice, 2 h before surgery. Gastric content was obtained immediately after intubation of the trachea. No significant difference in gastric volume and pH of gastric aspirate was found between the two groups. It is concluded that naloxone does not affect gastric emptying and gastric acid secretion to a degree great enough to protect against aspiration of gastric contents into the lungs. 相似文献
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Human lymphoblastoid cells produce extracellular matrix-degrading enzymes and induce endothelial cell proliferation, migration, morphogenesis, and angiogenesis 总被引:11,自引:0,他引:11
A. Vacca D. Ribatti M. Iurlaro A. Albini M. Minischetti F. Bussolino A. Pellegrino R. Ria M. Rusnati M. Presta V. Vincenti M. G. Persico F. Dammacco 《International Journal of Clinical & Laboratory Research》1998,28(1):55-68
Human lymphoproliferative diseases can be hypothesized to invade locally and to metastatize via mechanisms similar to those
developed by a variety of solid tumors, i.e., the secretion of extracellular matrix-degrading enzymes and stimulation of angiogenesis.
To assess this hypothesis, Namalwa, Raji, and Daudi cell lines (Burkitt’s lymphoma), LIK and SB cell lines (B-cell lymphoblastic
leukemia), CEM and Jurkat cell lines (T-cell lymphoblastic leukemia), and U266 cell line (multiple myeloma) were evaluated
for their capacity to produce matrix metalloproteinase-2 and -9, and urokinase-type plasminogen activator. These cell lines
were also assessed for their ability: (1) to produce the angiogenic basic fibroblast growth factor and vascular endothelial
growth factor; (2) to induce an angiogenic phenotype in cultured endothelial cells, represented by cell proliferation, chemotaxis,
and morphogensis; (3) to stimulate angiogenesis in different in vivo experimental models. All cell lines expressed the mRNA
for one or both metalloproteinases. Namalwa, Raji, LIK, SB, and U266 cells secreted the active form of both metalloproteinases,
while Daudi, CEM, and Jurkat cells produced metalloproteinase-2 but not -9. In contrast, urokinase-type plasminogen activator
was secreted only by SB cells. While Raji, LIK, SB, CEM, and Jurkat cells secreted both basic fibroblast growth factor and
vascular endothelial growth factor, Daudi and U266 cells produced only the former, and Namalwa cells only the latter. Accordingly,
the conditioned medium of all cell lines stimulated cell proliferation and/or chemotaxis in cultured endothelial cells, with
the exception of that of Namalwa cells which was ineffective. The conditioned medium of CEM and Jurkat cells induced morphogenesis
in cultured endothelial cells grown on a reconstituted basement membrane (Matrigel). Lastly, Namalwa, Raji, LIK, SB, U266,
CEM, and Jurkat cells induced angiogenesis and mononuclear cell recruitment in the murine Matrigel sponge model and in a chick
embryo chorioallantoic membrane assay. The extent of angiogenesis in both models was strictly correlated with the density
of the mononuclear cell infiltrate. The results indicate that human lymphoproliferative disease cells possess both local and
remote invasive ability via the secretion of matrix-degrading enzymes and the induction of angiogenesis which is fostered
by host inflammatory cells and by an intervening ensemble of angiogenic factors. 相似文献
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Smoking and female infertility: a systematic review and meta-analysis 总被引:11,自引:10,他引:11
The high prevalence of smoking among women in their reproductive years
continues to be a matter of concern. The negative effects of smoking on
general health are well known, but smoking may also affect fertility. The
objective of the present study was to perform a systematic review of the
literature to determine whether there is an association between smoking and
risk of infertility in women of reproductive age, and to assess the size of
this effect. In the 12 studies used for this meta- analysis, the overall
value of the odds ratio (OR) for risk of infertility in women smokers
versus non-smokers was 1.60 [95% confidence interval (CI) 1.34-1.91].
Studies of subfertile women undergoing in-vitro fertilization (IVF)
treatment also show a reduction in fecundity among women smokers. A
meta-analysis of nine studies found an OR of 0.66 (95% CI 0.49-0.88) for
pregnancies per number of IVF- treated cycles in smokers versus
non-smokers. Despite the potential limitations of meta-analyses of
observational studies, the evidence presented in this review is compelling
because of the consistency of effect across different study designs, sample
size and types of outcome. However, continued reassurance is needed that
the calculated overall effect is not in fact due to confounding variables.
相似文献