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41.
Adult offspring of severely diabetic pregnant rats are insulin resistant and display cardiovascular dysfunction. When pregnant they develop mild hyperglycaemia. Diets high in saturated fat have been implicated in the development of cardiovascular disease and vascular dysfunction. In the present study we have determined vascular function in small mesenteric arteries from offspring of normal (OC) and diabetic (OD) rats fed standard chow and offspring of diabetic rats fed a diet high in saturated fats (OD-HF) from weaning to adulthood, and throughout their subsequent pregnancies. OD rats displayed an increased sensitivity to noradrenaline (P < 0.05) and impaired sensitivity to the endothelium-dependent vasodilator, acetylcholine. The component of acetylcholine-induced relaxation attributable to endothelium-derived hyperpolarizing factor was reduced in OD-HF rats. Pregnant OD rats also demonstrated impaired maximum relaxation to acetylcholine (pregnant OD rats v. pregnant OC rats P < 0.05). In pregnant OD-HF rats noradrenaline sensitivity was enhanced and endothelium-dependent relaxation further reduced (pregnant OD-HF rats v. pregnant OC rats P < 0.001). The isoprostane, 8-epi-prostaglandin F2alpha, a marker of oxidative stress, was increased in pregnant OD rats (pregnant OD rats v. pregnant OC rats P  相似文献   
42.
Biro P  Weiss M  Gerber A  Pasch T 《Anaesthesia》2000,55(9):886-889
Handling and efficacy of a new video-optical intubation stylet were assessed in a simulated difficult tracheal intubation setting and compared with a conventional malleable stylet. Forty-five anaesthetists performed 10 tracheal intubations using both techniques. Laryngoscopy was performed by the observer, who created a grade 3 view according the classification by Cormack and Lehane. The time taken to place the tracheal tube and the final tracheal tube positions were documented. Mean (SD) intubation time for the video-optical stylet was 20.4 (7.7) s and for the malleable stylet 10.2 (3.3) s (p<0.01). With the video-optical stylet the trachea was correctly intubated in all 225 attempts; with the malleable stylet 44 (19.6%) oesophageal and 44 (19.6%) endobronchial intubations occurred (p<0.01). The video-optical intubation stylet enabled us to recognise inappropriate tracheal tube positions and to correct them immediately. This equipment can be considered a reliable and effective tool for management of the difficult airway.  相似文献   
43.
Tropisetron zur Prophylaxe von postoperativem Erbrechen bei Kindern   总被引:3,自引:0,他引:3  
BACKGROUND: Postoperative nausea and vomiting (PONV) after tonsillectomy is a common problem in children. Tropisetron is a new 5HT3 receptor antagonist and is successfully used in paediatric patients receiving cancer therapy. The aim of the study was to assess efficacy and safety of a single intravenous dose of tropisetron for prevention of PONV in paediatric patients at risk for postoperative vomiting. METHODS: In a randomised, double-blind, placebo-controlled trial, we studied 98 children aged 2-12 years undergoing tonsillectomy or adenotonsillectomy. Patients received placebo or tropisetron 0.1 mg (= 0.1 ml)/kg body weight immediately after induction of anesthesia. A standard general anesthetic technique (Sevoflurane/N2O/O2 without neuromuscular blockers or opioids) was used. Perioperative vital signs, grade of sedation and episodes of postoperative nausea and vomiting were recorded. RESULTS: No vomiting episodes occurred in 65.3% of the tropisetron treated patients compared to 34.7% of the placebo group (p = 0.0024). Only 10.2% of the tropisetron treated patients vomited more than 3 times compared to 22.4% of the control patients (p = 0.0004). The need for antiemetic rescue medication was significantly lower in the study group (10.4%) compared to 28.6% (p = 0.025). No significant adverse effects of the study medication were shown. CONCLUSION: A single intravenous prophylactic dose of tropisetron effectively reduces the incidence of PONV during the first 24 postoperative hours after tonsillectomy and/or adenoidectomy. Because of the low incidence of adverse effects, the prophylactic use of tropisetron seems to be safe and justified in paediatric surgical patients at high risk for postoperative vomiting.  相似文献   
44.
Hydroxyethyl starch (HES) solutions are widely used to replace intravascular volume. HES solutions differ from each other with regard to molecular weight and mode of hydroxyl substitution (degree of hydroxylation, C2:C6 hydroxyethyl ratio, concentration), factors which may have varying effects on coagulation. We studied, in vitro, three different HES preparations (molecular weight/degree of hydroxylation/concentration/C2:C6 ratio of substitution 70.000/0. 5/6%/3.2; Pharmacia & Upjohn Co., Erlangen, Germany; 130.000/0. 4/6%/11.2 and 200.000/0.5/6%/4.6; Fresenius Co., Bad Homburg, Germany) and, for comparison, lactated Ringer's solution (RL) at 33% and 66% dilution with whole blood. The influence of hemodilution was measured by using routine laboratory variables and SONOCLOT (Sonoclot II Coagulation and Platelet Function Analyzer, Sienco Co.) analysis, using a viscoelastic test, on the cellular as well as on the plasmatic hemostatic system. For statistical analysis of quantitative data, we used nonparametric analysis of variance and adequate post hoc tests. Qualitative data were analyzed by using the nonparametric Kruskal-Wallis test. A P value below 0.05 was considered significant. In contrast to the control group with RL, the liquid phase of coagulation (activated clotting time) was slightly affected by the 33% diluted HES solutions. HES 70.000, 130. 000, and 200.000 interfered significantly with the early stage of coagulation as expressed by the clot rate (gel/fibrin formation). Clot maturation and speed of maturation (time to peak) were strongly affected by HES 70.000 at all grades of dilution. HES 130.000 showed a faster clot formation process compared with the other HES solutions. HES 130.000 diluted 33% showed a better clot retraction as compared with the other HES solutions. In conclusion, in vitro hemodilution comparing different medium molecular weight HES solutions reveals that HES 130.000 seems preferable regarding some aspects of clot formation and retraction. RL affected clot formation only minimally, except for the early activation of clotting, which was measured by a shortened activated clotting time. IMPLICATIONS: We investigated the effect of different hydroxyethyl starch (HES) solutions (70.000, 130.000, 200.000) on coagulation. Regarding clot formation and retraction, HES 130.000 had some advantages over the other tested HES solutions. Lactated Ringer's solution affected coagulation only minimally, except for the early stage of clot formation.  相似文献   
45.
46.
Zusammenfassung Die Diskussion um die adjuvante Chemotherapie und adjuvante Radiochemotherapie bei Patienten mit komplett operiertem Magenkarzinom ist in Europa nach wie vor kontrovers. Eine hohe lokoregionale Rezidivrate und Fernmetastasierungsrate nach initial kompletter Resektion eines Magenkarzinoms zeigt deutlich den Bedarf einer effektiven adjuvanten Systemtherapie. Daher wurden in den letzten Jahren innerhalb klinischer Studien verschiedene adjuvante Therapieregimes untersucht, um die Prognose von Patienten mit lokalisiertem resektablem Magenkarzinom zu verbessern. Dabei wurden sowohl die adjuvante alleinige Chemotherapie und alleinige adjuvante Radiation als auch die adjuvante kombinierte Radiochemotherapie eingesetzt.  相似文献   
47.
48.
Malnutrition, a risk factor for osteoporotic fractures, is frequent in elderly people and, is underdiagnosed and undertreated. There are only few studies on the nutritional status of elderly people in Europe. The Mini Nutritional Assessment (MNA) is a non invasive and validated questionnaire to evaluate nutritional status in elderly people, classified in three groups: 1 degree score < 17: malnourished, 2 degrees score >17 and < 24: at risk of malnutrition, 3 degrees score >24: well-nourished, with a maximum of 30 points. Quantitative ultrasound of bone (QUS) is a method for assessing quality of bone which can be easily performed in nursing homes. Therefore, these two tests allowed to study the relationships between nutritional status and ultrasonic parameters of bone in 78 institutionalized women aged 86 +/- 6 years, living in 11 nursing homes around Lausanne (Switzerland). All were assessed by the MNA, had a measurement of the tricipital skin fold and of the grip strength. Functional status was evaluated by the scale "Activity of Daily Living" (ADL), and serum albumin level was measured when permitted. All had QUS of the calcaneus (with an Achilles, GE Lunar). The measured parameters are the Broadband Ultrasound Attenuation (BUA), attenuation of a band of ultrasonic frequencies through the medium, expressed in dB/MHz, and the Speed of Sound (SOS), speed of the ultrasounds through the medium, expressed in m/s. A third parameter, the stiffness index (SI), expressed as a percentage of the values obtained by the manufacturer in a young population and derived from BUA and SOS, was calculated automatically : SI = (0.67xBUA) + (0.28xSOS) - 420, expressed in percent compared to a young adult population (%YA). Fifteen percent of the women were undernourished and 58% were at risk of malnutrition. As expected, compared with the well-nourished minority, undernourished subjects had significant lower body mass index (BMI), tricipital skin fold (TSF), ADL score and albumin level (p < 0,01). The subjects "at risk of malnutrition" had significant lower BMI, ADL score (p < 0.01), tricipital skin fold and serum albumin (p < 0.05). Ultrasound parameters were low independently of the nutritional status. MNA score correlated significantly with tricipital skin fold (r = 0.508, p < 0.01), ADL (r = 0.538, p < 0.01) and albumin serum level (r = 0.409, p = 0.01). There was a trend for a correlation between the MNA and the ultrasound parameter BUA (r = 0.207, p = 0.07), whereas no correlation was found with SOS and SI. A multivariate analysis showed that tricipital skin fold and ADL explained 61% of the variance of the MNA. In conclusion, using simple and non invasive methods, this study showed that malnutrition and osteoporosis are frequent in institutionalized elderly persons in our country, and the ultrasound parameters are influenced by many others factors in addition to nutrition, especially at this age and in elderly residents of nursing homes.  相似文献   
49.
Multicentric Castleman’s disease (MCD) is a rare polyclonal lymphoproliferative disorder that is typically accompanied by an overproduction of circulating cytokines (mainly interleukin-6). We here report the case of a 40-year-old HIV-negative woman with pulmonary manifestation of MCD. There is no standard treatment for MCD. In our patient, various treatment courses with immunomodulatory drugs were unsuccessful. Finally, treatment with the interleukin-6 receptor antibody tocilizumab has resulted in continual clinical improvement over the last 5 years.  相似文献   
50.
There are few putative macroevolutionary trends or rules that withstand scrutiny. Here, we test and verify the purported tendency for animal clades to reach their maximum morphological variety relatively early in their evolutionary histories (early high disparity). We present a meta-analysis of 98 metazoan clades radiating throughout the Phanerozoic. The disparity profiles of groups through time are summarized in terms of their center of gravity (CG), with values above and below 0.50 indicating top- and bottom-heaviness, respectively. Clades that terminate at one of the “big five” mass extinction events tend to have truncated trajectories, with a significantly top-heavy CG distribution overall. The remaining 63 clades show the opposite tendency, with a significantly bottom-heavy mean CG (relatively early high disparity). Resampling tests are used to identify groups with a CG significantly above or below 0.50; clades not terminating at a mass extinction are three times more likely to be significantly bottom-heavy than top-heavy. Overall, there is no clear temporal trend in disparity profile shapes from the Cambrian to the Recent, and early high disparity is the predominant pattern throughout the Phanerozoic. Our results do not allow us to distinguish between ecological and developmental explanations for this phenomenon. To the extent that ecology has a role, however, the paucity of bottom-heavy clades radiating in the immediate wake of mass extinctions suggests that early high disparity more probably results from the evolution of key apomorphies at the base of clades rather than from physical drivers or catastrophic ecospace clearing.  相似文献   
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