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81.
Non-obstetrical acute abdomen during pregnancy   总被引:7,自引:0,他引:7  
Acute abdomen in pregnancy remains one of the most challenging diagnostic and therapeutic dilemmas today. The incidence of acute abdomen during pregnancy is 1 in 500-635 pregnancies. Despite advancements in medical technology, preoperative diagnosis of acute abdominal conditions is still inaccurate. Laboratory parameters are not specific and often altered as a physiologic consequence of pregnancy. Use of laparoscopic procedures as diagnostic tools makes diagnosis of such conditions earlier, more accurate, and safer. Appendicitis is the most common cause of the acute abdomen during pregnancy, occurring with a usual frequency of 1 in 500-2000 pregnancies, which amounts to 25% of operative indications for non-obstetric surgery during pregnancy. Surgical treatment is indicated in most cases, as in nonpregnant women. Laparoscopic procedures in the treatment of acute abdomen in pregnancy proved safe and accurate, and in selected groups of patients are becoming the procedures of choice with a perspective for the widening of such indications with more frequent use and subsequent optimal results. Despite these advances, laparotomy still remains the procedure of choice in complicated and uncertain cases.  相似文献   
82.
Spontaneous metallic Pb whisker formation from Pb and Bi containing Al-alloy’s surfaces is a newly discovered phenomenon. The whiskers display unique formations, growth and morphology, which give the opportunity to be applied for specialized sensor and electronics applications. Within this work, the impact of environmental conditions (gas composition and moisture) is investigated and correlated with the modification of whisker evolution and growth dynamics. Furthermore, the residual stress state of the aluminum matrix using deep cryogenic treatment is modified and used to further increase whisker nucleation and growth by up to three- and seven-fold, respectively, supported by quantitative results. The results of this paper indicate the possibility to manipulate the whisker not only in terms of their kinetics but also their morphology (optimal conditions are 20% O2 and 35% humidity). Such features allow the tailoring of the whisker structure and surface to volume ratio, which can be optimized for different applications. Finally, this research provides new insight into the growth dynamics of the whiskers through in situ and ex situ measurements, providing further evidence of the complex nucleation and growth mechanisms that dictate the spontaneous growth of Pb whiskers from Al-alloy 6026 surfaces with growth velocities up to 1.15 µm/s.  相似文献   
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A simple protocol has been developed for the chemoselective synthesis of ferrocene-containing Rauhut–Currier adducts from 1-ferrocenyl-2-nitroethene and vinyl ketones using 20 mol% of triphenylphosphine. Multifunctional ferrocene derivatives were obtained in moderate to high yields (51–92%) by the coupling between the α-position of vinyl ketones and the β-position of the nitroalkene. The study of the Rauhut–Currier reaction under the described conditions showed that the strong electron-donating group at the β-position of nitroalkenes plays a significant role in the reaction outcome due to prevention of polymerization and stabilization of the zwitterionic intermediate. Additionally, a preparative synthesis of 4-ferrocenyl-3-methylene-5-nitropentan-2-one was carried out and its synthetic transformations showed easy conversion to other useful building blocks.

A simple method has been developed for the chemoselective synthesis of ferrocene-containing Rauhut–Currier adducts from 1-ferrocenyl-2-nitroethene and vinyl ketones catalyzed by triphenylphosphine.  相似文献   
85.
Archives of Gynecology and Obstetrics - To describe a case series of patients with malignant ovarian germ cell tumors (MOGCT) treated exclusively with fertility-sparing surgery (FSS) with or...  相似文献   
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Increased hepatic lipid content and decreased insulin sensitivity have critical roles in the development of cardiometabolic diseases. Therefore, our objective was to investigate the dose-response effects of consuming high fructose corn syrup (HFCS)-sweetened beverages for two weeks on hepatic lipid content and insulin sensitivity in young (18–40 years) adults (BMI 18–35 kg/m2). In a parallel, double-blinded study, participants consumed three beverages/day providing 0% (aspartame: n = 23), 10% (n = 18), 17.5% (n = 16), or 25% (n = 28) daily energy requirements from HFCS. Magnetic resonance imaging for hepatic lipid content and oral glucose tolerance tests (OGTT) were conducted during 3.5-day inpatient visits at baseline and again at the end of a 15-day intervention. During the 12 intervening outpatient days participants consumed their usual diets with their assigned beverages. Significant linear dose-response effects were observed for increases of hepatic lipid content (p = 0.015) and glucose and insulin AUCs during OGTT (both p = 0.0004), and for decreases in the Matsuda (p = 0.0087) and Predicted M (p = 0.0027) indices of insulin sensitivity. These dose-response effects strengthen the mechanistic evidence implicating consumption of HFCS-sweetened beverages as a contributor to the metabolic dysregulation that increases risk for nonalcoholic fatty liver disease and type 2 diabetes.  相似文献   
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Background  Different materials have been evaluated for anastomotic reinforcement to prevent gastrointestinal anastomotic leakage. In this experimental study, small intestinal submucosa (SIS) was tested as a sealing for stapled colonic anastomosis in a porcine model. The aims of this study were to determine the macroscopic and microscopic outcomes and to evaluate the safety and feasibility of applying SIS for anastomotic sealing. Materials and methods  Circular stapled anastomoses were performed in 18 pigs. Standard anastomosis in the control group (n = 8) was compared to an SIS-sealed anastomosis in the study group (n = 10). After 30 days, anastomotic segments were examined for macroscopic and microscopic regeneration and their resistance to mechanical stress. Furthermore, animal survival and clinical course were evaluated. Results  None of the animals developed anastomotic leakage, intraabdominal abscess, or peritonitis. Shrinkage of SIS was evident in nine of ten animals. Encapsulation and displacement of the SIS patches were seen in two animals. Quantity of anastomotic granulation tissue and rate of complete mucosal coverage of anastomotic line were increased in SIS-sealed anastomoses without reaching significance. Moreover, no significant differences were found in the rate of survival of the animals, anastomotic stricture formation, intraabdominal adhesions, anastomotic bursting pressure, and microscopic healing parameters of the anastomosis between stapled colonic standard anastomosis and anastomosis protected by SIS. Conclusion  The results of this study indicate a safe use of SIS for anastomotic reinforcement in a porcine model. Adverse effects like strictures, increased adhesions, and anastomotic abscesses were absent. Promoting effects on colonic wound healing by SIS were microscopically evident. The results argue for a careful clinical evaluation in humans.  相似文献   
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