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PURPOSE OF REVIEW: To appraise a new approach to laparoscopic surgery for infertility caused by advanced endometriosis. RECENT FINDINGS: Endometriosis is a common systemic and local disease with altered peritoneal function, which requires both systemic and local treatment. Medication alone cannot improve infertility, and laparoscopic treatment, particularly in severe endometriosis, has a high recurrence rate and is often limited by technical difficulties. Novel treatment strategies have therefore to be sought, especially in women who do not want in-vitro fertilization as a first option, either because they suffer from pain in addition to infertility or want to enhance their fertility over many cycles. SUMMARY: Two-step operative laparoscopy with interval pituitary suppression by means of gonadotrophin-releasing hormone analogues reduces the extent of endometriosis, as classified by the American Fertility Association, and appears to be a promising method of achieving optimal cytoreduction and facilitating complicated surgery in severe endometriosis, while protecting the ovary from unnecessary trauma. A large-scale well-designed study is needed to confirm that this treatment leads to improved pregnancy rates.  相似文献   
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Problem Implantation failure and early pregnancy loss are common following natural conceptions and they are particularly important clinical hurdles to overcome following assisted reproduction attempts. The importance of adequate vascular development and maintenance during implantation has recently become a major focus of investigation. Materials and methods Review of current published literature was undertaken to summerize the cells and cell products that regulate tissue vascularity during implantation. Results Vascular development at the maternal fetal interface can be regulated by a number of different cell types; two principal candidates are trophoblast and natural killer cells. A wide range of soluble factors, some with well established angiogenic functions as well as other more novel factors, can contribute to vascular development and maintenance at the maternal–fetal interface. Conclusions Robust vascular development occurs during implantation and early placentation of normal pregnancies. Studies to define the extent and mechanisms by which defects in vascularity contribute to human implantation failure and early miscarriage need to be undertaken. Vascular development during implantation is mediated by numerous cell types and cell products and aberrant vascularity likely contributes to implantation failure and early pregnancy loss.  相似文献   
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The metabolism of 1-nitro[14C]pyrene (14C-1-NP; 8.1 microM) was studied in cultured (20 hr) rabbit alveolar macrophages, lung tissue, and tracheal tissue. Metabolites from the incubation medium and from the macrophages and respiratory tract tissues were extracted and then analyzed and quantified by high-pressure liquid chromatography. The following metabolites were detected in the lung and tracheal tissue incubation medium: 1-nitropyrene-4,5-dihydrodiol, N-acetyl-1-aminopyrene, 1-aminopyrene, and 10-hydroxy-1-nitropyrene. Nitropyrene phenols (4-, 5-, 6-, 8- or 9-hydroxy-1-nitropyrene) and 3-hydroxy-1-nitropyrene were only detected in the lung and tracheal tissue and not in the incubation medium for these tissues. Minor amounts of 1-aminopyrene and 10-hydroxy-1-nitropyrene were detected in the macrophage incubation medium, and only minute quantities of 1-nitropyrene-4,5-dihydrodiol, 1-aminopyrene, and 10-hydroxy-1-nitropyrene were detected in macrophages. The total percentage of 1-NP metabolism was significantly greater in the lung and tracheal tissue (28.0 and 23.0% of the recovered 14C, respectively) than in the alveolar macrophages (6.3% of the recovered 14C). The tracheal tissue was found to have the highest activity both in 1-NP metabolism and intracellular metabolite concentration. A major portion of the 1-NP metabolites produced was released into the incubation medium. The majority of the metabolites produced by tracheal and lung tissue, 70 and 84%, respectively, were ethyl acetate extractable. The metabolites retained within the cells or tissues were also predominantly ethyl acetate extractable rather than water soluble (83% for the macrophages and trachea, 95% for the lung tissue). The metabolite profiles obtained demonstrate that metabolism by both nitro reduction and ring oxidation occurs in respiratory tissue, and a degree of tissue specificity in the formation of metabolites exists. Ring oxidation was demonstrated in the lung and tracheal tissue, but very little occurred in the macrophages.  相似文献   
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Bone scintigraphy in the reflex sympathetic dystrophy syndrome   总被引:1,自引:0,他引:1  
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