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91.
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To evaluate the efficacy of a second-look operative laparoscopy following a reproductive surgery, a randomized study was conducted on women who failed to conceive 1 year following terminal salpingostomy or following salpingo-ovariolysis by laparotomy. There is no significant difference in the cumulative probability of pregnancy at 12, 24, and 36 months follow-up between women who underwent second-look operative laparoscopy 1 year after salpingo-ovariolysis (27%, 67%, and 67%) and women who were continued to be observed expectantly (27%, 45%, and 52%, respectively). The cumulative probability of conception at 12, 24, and 36 months follow-up in women who underwent second-look laparoscopy 1 year after salpingostomy was 6%, 18%, and 18% and in women who were observed expectantly was 5%, 21%, and 27%, respectively (P = no significant). The incidence of ectopic pregnancy which was high (about one-half of patients who conceived) was also not affected by this procedure. This study suggests that second-look operative laparoscopy 1 year after terminal salpingostomy or salpingo-ovariolysis does not increase the pregnancy rate or decrease the incidence of ectopic pregnancy. Women who fail to conceive 1 year after a reproductive surgery still maintain some of their reproductive potential, but the risk of having an ectopic pregnancy is high.  相似文献   
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In vivo antimutagenic activity of beta-carotene in rat spleen lymphocytes   总被引:1,自引:0,他引:1  
The anticarcinogenic effects of beta-carotene (BC) have beenextensively investigated, but only in vitro assays have examinedthe ability of BC to modulate gene mutation. In view of thecurrent interest in the provitamin as a cancer chemopreventiveagent, and the association between mutagenesis and carcinogenesis,we have dosed Fischer 344 rats with the model carcinogen N-ethyl-N-nitrosourea(ENU) and investigated the relationships among BC intake, itstissue accumulation, and antimutagen activity. Animals receiveddrinking water supplemented with BC at doses of 0–0.25%ad libitum, using three dosing schedules. In one group BC dosingcommenced before, and continued for three alternating weeksafter i.p. injection of 100 mg ENU/ kg; another group was givenBC only after mutagen treatment Animals from the first two groupswere sacrificed 5 weeks post-mutagen treatment, and cells wereisolated from the spleen to determine the frequency of 6-thioguanine-resistant(6-TGr) T-lymphocytes. The presence of BC caused a reductionin the frequency of 6-TGr T-cells produced by ENU, but the inhibitionwas non-linear within the range of BC doses used. BC intakeonly after mutagen treatment was more effective than the combinationof preand post-mutagen intake. In the third group, rats weretreated with 100 mg ENU/kg, and BC administration was continuedat a fixed dose of 0.15% in the drinking water for 2, 4, 6,or 8 weeks. Measurement of the frequency of 6-TGr T-cells atthe end of the specified times showed >50% reduction in ENU-mediatedmutagenicity throughout the experiment. Analysis of BC levelsin the liver and in the spleen following BC intake before andduring mutagen exposure revealed higher levels than when BCwas given only after mutagen treatment. Continuous intake ofBC also showed increased tissue levels. There were some correlationsobserved between BC tissue levels and the antimutagenic effectsfor the first two groups, but these correlations were not statisticallysignificant, possibly due to the small numbers of animals used.Taken together, the results demonstrate that intact BC is absorbed,stored, and exerted antimutagenic effects against a chemicalcarcinogen in rats without first being transformed to retinolin the gastrointestinal tract.  相似文献   
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The synthesis and structure-activity relationship of N(6)-cyclopentyl-3'-substituted-xylofuranosyladenosine analogues with respect to various adenosine receptors were explored in order to identify selective and potent antagonists and inverse agonists for the adenosine A(1) receptor. In particular, the effects of removal of the 5'-OH group and introduction of selected substituents at the 3'-NH(2) position of 9-(3-amino-3-deoxy-beta-D-xylofuranosyl)-N(6)-cyclopentyladenine were probed. A solid phase-assisted synthetic approach was used to optimize the 3'-amide functionality. In view of the general concern of the presence of a 5'-OH moiety with regard to cellular toxicity, the present study describes 5'-deoxy compounds with reasonable affinity for the human adenosine A(1) receptor. Interestingly, this study shows that optimization of the 3'-"up" amide substituent can substantially compensate for the drop in affinity for the adenosine A(1) receptor, which is generally observed upon removal of the 5'-OH group. The fact that for several 3'-amido-substituted (5'-deoxy)-N(6)-cyclopentyladenosine derivatives, guanosine 5'-triphosphate-induced shifts in K(i) values were significantly lower than 1 implies that these analogues behave as inverse agonists. This is further supported by their 1,3-dipropyl-8-cyclopentylxanthine-like capacity to increase forskolin-induced adenosine cyclic 3',5'-phosphate production.  相似文献   
98.
Objective: There is evidence that individuals high in hypochondriasis overestimate the likelihood of ambiguous symptoms being indicative of serious illness. However, it is not known whether this tendency is unique to hypochondriasis or whether it can be attributed to high negative affectivity or other anxiety symptoms often found to be comorbid with hypochondriasis. Method: College students (N=133) completed measures of hypochondriasis, depression, anxiety, worry, avoidance and estimated the likelihood of various symptoms indicating catastrophic and minor illnesses. Results: Even after entering the other self-report variables, hypochondriasis was the only variable to predict estimates of the likelihood of serious illness. Conversely, being female, high levels of negative affect, agoraphobic avoidance when accompanied by others and higher estimates about the likelihood of symptoms leading to catastrophic illnesses best predicted hypochondriasis scores. Conclusion: Dysfunctional beliefs about illness appear to be unique to hypochondriasis and to uniquely contribute to the prediction of hypochondriasis.  相似文献   
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