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101.
102.
羽叶三七叶中甙类成分的研究 总被引:3,自引:0,他引:3
从羽叶三七叶中分离到十三种甙类成分,经FAB-MS,13CNMR谱,双照射1HN-MR谱,1H-1H COSY谱及与标准品直接对照,证明十一种为已知化合物,分别为人参皂甙F1(Ⅰ),F2(Ⅱ),F3(Ⅲ),Rg2(Ⅳ),Ra(Ⅴ),Rd(Ⅵ),Rb1(Ⅷ),Rb3(Ⅷ),24(S)-假人参甙F11(Ⅸ),人参黄酮(Ⅹ)和珠子参甙F1(Ⅺ);另外两种为新的达玛烷型皂甙,命名为羽叶三七甙F1(Ⅻ)和F2(ⅫⅠ),并确定其化学结构。同时修正珠子参甙F3的结构。进一步阐明人参黄酮甙结构中的两个糖的连接方式。 相似文献
103.
Benedict CR; Ryan J; Todd J; Kuwabara K; Tijburg P; Cartwright J Jr; Stern D 《Blood》1993,81(8):2059-2066
Factor Xa is a central procoagulant enzyme, linking the intrinsic and extrinsic activation mechanisms to the final common pathway of coagulation. To assess its contribution to pathologic thrombosis, studies were performed in a canine coronary thrombosis model. Thrombus formation was initiated by the application of electric current via a needle electrode placed in the lumen of the left circumflex coronary artery. When 50% occlusion of the vessel developed, the current was stopped and animals received an intravenous bolus of either saline, bovine glutamyl-glycinyl-arginyl-factor Xa (Xai), a competitive inhibitor of factor Xa assembly into the prothrombinase complex, Factor X, or heparin. Animals infused with saline or factor X (300 micrograms/kg) developed total occlusion of the vessel due to a fibrin/platelet thrombus in 70 +/- 11 minutes (36 of 36 animals) and 74 +/- 13 minutes (8 of 8 animals), respectively. In contrast, infusion of Xai prevented thrombus formation completely at a dose of 300 micrograms/kg (8 of 8 animals). As the dose of Xai was decreased, its antithrombotic effect was diminished, with a patency rate of only 2 of 6 animals at a dose of 90 micrograms/kg. Xai at 300 micrograms/kg prevented the accumulation of 125I-fibrinogen/fibrin at the site of the coronary thrombus by approximately 63% and decreased deposition of 111In-labeled platelets by approximately 57%. Hemostatic parameters of animals infused with Xai demonstrated prolongation of the PT and dose- dependent increased extravascular bleeding tendency. These data indicate that factor Xa has a comparably important role in thrombus formation and extravascular hemostasis, and contrast with previous results in this same animal model in which IXai selectively prevented clotting in the coronary vasculature. 相似文献
104.
The palpation and enucleation of occult insulinomas (less than 15 mm) can be a difficult surgical problem even with good arteriographic localization. In the authors' limited experience, confirmation of arteriographic findings by pancreatic venous sampling provided little additional localizing information. However, if arteriography is negative or equivocal, venous sampling can indicate the segment of pancreas to be "blindly" resected if the adenoma is not palpable. Venous sampling may be misleading in polyendocrine syndromes because of the frequency of multiple adenomas and variable hormone production. 相似文献
105.
WL Craig CR Ramsay S Fielding ZH Krukowski 《Annals of the Royal College of Surgeons of England》2014,96(6):466-474
Introduction
This study describes variability of treatment for differentiated thyroid cancer among thyroid surgeons, in the context of changing patterns of thyroid surgery in the UK.Methods
Hospital Episodes Statistics on thyroid operations between 1997 and 2012 were obtained for England. A survey comprising six scenarios of varying ‘risk’ was developed. Patient/tumour information was provided, with five risk stratified or non-risk stratified treatment options. The survey was distributed to UK surgical associations. Respondent demographics were categorised and responses analysed by assigned risk stratified preference.Results
From 1997 to 2012, the Hospital Episode Statistics data indicated there was a 55% increase in the annual number of thyroidectomies with a fivefold increase in otolaryngology procedures and a tripling of cancer operations. Of the surgical association members surveyed, 264 respondents reported a thyroid surgery practice. Management varied across and within the six scenarios, and was not related consistently to the level of risk. Associations were demonstrated between overall risk stratified preference and higher volume practice (>25 thyroidectomies per year) (p=0.011), fewer years of consultant practice (p=0.017) and multidisciplinary team participation (p=0.037). Logistic regression revealed fewer years of consultant practice (odds ratio [OR]: 0.96/year in practice, 95% confidence interval [CI]: 0.922–0.997, p=0.036) and caseload of >25/year (OR 1.92, 95% CI: 1.044–3.522, p=0.036) as independent predictors of risk stratified preference.Conclusions
There is a substantial contribution to thyroid surgery in the UK by otolaryngology surgeons. Adjusting management according to established case-based risk stratification is not widely applied. Higher caseload was associated with a preference for management tailored to individual risk. 相似文献106.
G. Purcell-Jones BSc MRCP FFARCS F. Dormon MB BS FFARCS Registrars E. Sumner BM BCh FFARCS Consultant 《Anaesthesia》1987,42(12):1316-1320
This is a retrospective study on the use of postoperative opioids in neonates admitted to the surgical intensive care unit at Great Ormond Street over a 5-year period (1980-84). A total of 131 (14%) babies received opioids out of 933 neonates admitted to the unit. The use of opioids increased from 9.7% to 27.2% of admitted cases during the survey period. Postoperative ventilation of the lungs was necessary in 240 (25.7%) cases and 88 (36.6%) of these were given opioids. Four babies initially failed to wean from controlled ventilation as a result of opioid induced respiratory depression. A total of 51 (7.35%) spontaneously breathing neonates received opioids and seven (13.7%) of these developed apnoea or respiratory failure thought to be induced by opioids. The administration of opioids by nurses occurred most frequently in the late evening and early hours of the morning, when medical cover is at its lowest level. 相似文献
107.
1) By the action of thiouracil the follicular cell is not brought into the state of physiological inactivity and it shows signs of apparent secretion which differ however in details remarkably from the effective secretion stage. 2.) The quantity of follicular cells in mitosis is temporarily increased to the multiple. This disturbance is the result of the inhibition of caryokinesis in the stage of metaphase. 3) The absolute quantities of ribonucleic and of desoxyribonu-cleic acid are considerably reduced. 4) The ratio KNA/DNA shows a decrease to a fractional part of the normal value, according to the increase of the cell mass. 相似文献
108.
Left ventricular volumes measured by MR imaging 总被引:9,自引:0,他引:9
We assessed the potential of proton magnetic resonance (MR) imaging for accurately measuring left ventricular volumes using 15 latex casts of excised human left ventricles. The casts were submerged in water to stimulate the endocardial left ventricular cavity interface in in vivo imaging conditions. Tomographic image sections perpendicular to the long axis of the cast were obtained, spanning each cast from apex to base. Simpson's rule was used to calculate the cast volumes. Correlation between the actual cast volumes (as measured by the displacement method) and the calculated volumes using MR imaging for the 15 casts was excellent. Our data demonstrate that MR imaging accurately measures cardiac chamber volumes in this in vitro model. 相似文献
109.
S Caserío C Gallego P Martin MT Moral CR Pallás A Galindo 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(10):1571-1577
Aim: To analyse the main prenatal and postnatal features of congenital chylothorax (CC), and the outcome including mid‐term follow‐up. Methods: We searched our databases for CC diagnosed between 1990 and 2006. Data of 29 cases were retrieved and analysed. Follow‐up until 3 years of age was available for all patients. Results: Most patients were diagnosed prenatally (94%) and most cases were complicated by foetal hydrops (66.7%). The overall survival rate at 3 years was 56%. A significantly poorer outcome was observed when foetal hydrops, preterm birth < 34 weeks, large effusions and/or early‐onset pneumothorax were present. An important but not significant improvement in the survival rate was observed through the study period; while in 1990–1998, the survival rate was 41.7%, from 1999 to 2006 it was 66.7% (p = 0.19). In the mid‐term follow‐up, we did not observe any recurrence of CC and most infants remain asymptomatic. However, 27% of survivors were diagnosed as having asthma in early infancy. Conclusion: CC still carries a significant risk of perinatal mortality. However, continuous advances in foetal and neonatal medicine are improving the prognosis of these patients, and nowadays most of them are likely to survive. Beyond the neonatal period, most survivors have an uneventful outcome. 相似文献
110.
Strangulation in child abuse: CT diagnosis 总被引:2,自引:0,他引:2
The central nervous system is commonly affected in child abuse. Between April 1985 and July 1986 three infants were identified in whom the primary mode of injury had been strangulation. In each case computed tomography (CT) demonstrated a large cerebral infarction confined to vascular territories associated with small subdural hematomas. There was no history or visible evidence of significant head trauma. Autopsy of one infant confirmed the presence of a hemispheric infarct, thin subdural hematoma, and an area of subintimal hemorrhage in the carotid artery ipsilateral to the infarct. The remaining two patients survived with residual hemiparesis. CT findings of a large cerebral infarction with an associated subdural hematoma in an infant without a history of a significant trauma should suggest the possibility of child abuse and may be the primary manifestation of abuse in some patients. 相似文献