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41.
目的:观察理气中药经验组方对糖尿病大鼠胃排空延迟的干预作用。方法:雌雄各半成年SD大鼠110只,随机分为正常组(A组)、糖尿病中药组(B组)、糖尿病胃复安组(C组)、糖尿病组(D组)。A组、D组1次/d按10 mL/只予0.9%生理盐水灌胃,B组1次/d按8 mL/只予中药煎剂灌胃,C组1次/d按0.5 mg/只予胃复安片灌胃。喂养12周后,行13C胃排空实验及甲基橙水溶液胃排空实验,观察各组大鼠胃排空情况。结果:糖尿病大鼠胃排空较正常大鼠明显延迟(P0.01),糖尿病大鼠胃排空延迟模型制作成功。糖尿病中药组和糖尿病胃复安组大鼠胃排空较糖尿病组快(P0.01);糖尿病中药组大鼠胃排空较糖尿病胃复安组大鼠快(P0.05)。结论:常规喂养12周后糖尿病大鼠出现胃排空延迟。理气中药陈皮、枳实、木香、香附组方煎剂和胃复安均能促进糖尿病大鼠胃排空,理气中药组方煎剂的效果优于胃复安。 相似文献
42.
目的 前房注射卡波姆建立大鼠高眼压模型,观察卡波姆升眼压效果及对大鼠眼前节和视网膜的影响。方法 随机选取30只SD大鼠,注射前3 d早晚测量基线眼压。右眼定为实验眼,左眼定为对照眼,右眼放出房水后将30 μL的5 g·L-1卡波姆混悬液注入前房,每日早10时、晚22时在大鼠清醒状态下测量眼压。每周进行双眼眼前节照相并对比。4周末处死26只大鼠(另4只持续观察眼压变化至注射后9周)并取双眼眼球行HE染色,观察实验眼与对照眼视网膜形态,对比视网膜厚度及房角形态。结果 注射前,实验眼白天和夜间眼压分别为(11.10±0.90)mmHg(1 kPa=7.5 mmHg)和(11.92±1.07)mmHg,对照眼分别为(11.22±1.07)mmHg和(11.76±1.08)mmHg;实验眼与对照眼相比,白天、夜间眼压差异均无统计学意义(均为 P>0.05);白天与夜间眼压相比,实验眼、对照眼差异均有统计学意义(均为P<0.05)。卡波姆在前房中呈现出弥散型和沉积型两种存在方式,弥散型和沉积型大鼠1周内眼压分别为(17.83±3.54)mmHg和(13.00±1.55)mmHg,两者相比差异具有统计学意义(P<0.05)。注射后第1天至第19天,实验眼与对照眼白天眼压相比差异均具有统计学意义(均为P<0.05);注射后第1天至第27天,实验眼与对照眼夜间眼压相比差异均具有统计学意义(均为P<0.05)。实验眼视网膜形态发生改变,注射后4周视网膜厚度为(254.70±21.80)μm,与对照眼的(346.73±24.63)μm相比,差异有统计学意义(P=0.00)。实验眼前房充满卡波姆及虹膜的混合成分,紧贴角膜内皮并延伸至房角,堵塞小梁网结构,正常虹膜形态消失;对照眼房角形态正常。结论 前房注射卡波姆建立大鼠高眼压模型,可维持高眼压4周以上,昼夜眼压差异较为明显,夜间眼压较白天更高,4周后视网膜出现高眼压损伤后的表现。 相似文献
43.
Marion Tardieu Najat Salameh Line Souris David Rousseau Laurène Jourdain Hanadi Skeif François Prévot Ludovic de Rochefort Denis Ducreux Bruno Louis Philippe Garteiser Ralph Sinkus Luc Darrasse Marie Poirier-Quinot Xavier Maître 《NMR in biomedicine》2022,35(7):e4701
Magnetic resonance elastography aims to non-invasively and remotely characterize the mechanical properties of living tissues. To quantitatively and regionally map the shear viscoelastic moduli in vivo, the technique must achieve proper mechanical excitation throughout the targeted tissues. Although it is straightforward, ante manibus, in close organs such as the liver or the breast, which practitioners clinically palpate already, it is somewhat fortunately highly challenging to trick the natural protective barriers of remote organs such as the brain. So far, mechanical waves have been induced in the latter by shaking the surrounding cranial bones. Here, the skull was circumvented by guiding pressure waves inside the subject's buccal cavity so mechanical waves could propagate from within through the brainstem up to the brain. Repeatable, reproducible and robust displacement fields were recorded in phantoms and in vivo by magnetic resonance elastography with guided pressure waves such that quantitative mechanical outcomes were extracted in the human brain. 相似文献
44.
《Acta orthopaedica et traumatologica turcica》2019,53(2):145-149
ObjectiveThe aim of study was to analyze the association between Quadriceps Angle (QA) and plantar pressure, navicular height (NH), and calcaneo-tibial angle (CTA).MethodsA total of 64 volunteers (mean age: 22.25 ± 2.54 (range:19–33)) participated in this cross sectional study. EMED-m (Novel GmbH, Germany) electronic pedobarograph was employed for dynamic plantar pressure measurement using two step protocol. The angle between the vertical axis of calcaneus and the long axis of Achilles tendon for CTA. The height of navicular tubercle from the ground was measured while the subject was standing on both feet for NH. QA was measured while the subject was standing in a relaxed posture where both feet bearing equal weight.ResultsThere were significant negative correlations between QA and maximum force (MxF) under the 4th. metatarsal head (MH4). The QA was also significantly correlated with MxF and force-time integral (FTI) under the bigtoe (BT). FTI under the 3rd. metatarsal head (MH3), MH4 and 5th. metatarsal head (MH5) were significantly negatively correlated with QA. Pressure-time integral (PTI) under the MH4 and MH5 were found to be significantly negatively correlated with QA. A significant correlation was also found between QA and NH (p < 0.0001), whilst there was no correlation between QA and CTA. Regression analysis showed that NH was appeared as the major contributor for the QA (β = −0.49, p < 0.001) in the dynamic condition, followed by BT-FTI (β = 0.37, p < 0.001) and MH5-MxF (β = −0.21, p < 0.037).ConclusionThese findings may imply that the NH which can at least be controlled by appropriate shoe inserts may affect QA. This way, loading pattern of both plantar region and whole lower extremity may be altered.Level of evidenceLevel III, Diagnostic Study. 相似文献
45.
Could non-HDL-cholesterol be a better marker of atherogenic dyslipidemia in obstructive sleep apnea?
《Sleep medicine》2021
Background/objectiveObstructive sleep apnea (OSA) is independently associated with dyslipidemia, a surrogate marker of atherosclerosis. Low-density lipoprotein (LDL)-cholesterol is accepted as a major independent risk factor for cardiovascular disease. However, non-high-density lipoprotein (HDL)-cholesterol is a better marker of atherogenic dyslipidemia and recommended as a target of lipid lowering therapy. We aimed to assess the prevalence of atherogenic dyslipidemia, and relationship between OSA severity and serum LDL-cholesterol and non-HDL cholesterol levels in OSA patients.MethodsWe retrospectively evaluated treatment naïve 2361 subjects admitted to the sleep laboratory of a university hospital for polysomnography. All subjects’ lipid profile including total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, and non-HDL-cholesterol were measured.ResultsOut of 2361 patients (mean age 49.6 ± 11.9 years; 68.9% male, apnea-hypopnea index 36.6 ± 28.4/h), 185 (7.8%) had no OSA and 2176 (92.2%) had OSA. Atherogenic dyslipidemia prevalence was high (57–66%) in OSA patients, and especially increased in severe OSA compared to other groups (p < 0.05). Though total and LDL-cholesterol did not differ between those with and without OSA, non-HDL-cholesterol (p = 0.020), and triglycerides (p = 0.001) were higher and HDL-cholesterol levels (p = 0.018) were lower in OSA patients than non-OSA. Non-HDL-cholesterol was significantly correlated with OSA severity (p < 0.001) and hypoxia parameters (p < 0.01), whereas LDL-cholesterol showed no correlation.ConclusionsAtherogenic dyslipidemia is highly prevalent and non-HDL-cholesterol levels are significantly increased, predominantly in severe OSA patients. Non-HDL-cholesterol but not LDL-cholesterol, is significantly correlated with OSA severity and hypoxia parameters. Therefore, it could be better to use non-HDL-cholesterol, which is a guideline recommended target of lipid therapy, as a marker of atherosclerotic cardiovascular risk in OSA patients. 相似文献
46.
47.
《Anaesthesia and Intensive Care Medicine》2020,21(12):668-672
The invasive measurement of physiological pressures is a common requirement in anaesthesia and intensive care medicine. From arterial blood pressure to intracranial pressure, these calculated variables give a swift graphical and numerical representation of a patient's current physiological status. This allows us to respond rapidly to conditions outside our preferred parameters and to carefully titrate treatment to target effects. These systems are, however, not infallible. An understanding of the principles of their function will promote appropriate use and an ability to recognize and react to sources of error. This article aims to furnish the reader with this level of understanding in order to inform their academic and clinical practice. 相似文献
48.
《Journal of Medical Imaging and Radiation Sciences》2015,46(4):442-449
The purpose of this literature review is to investigate clinical treatment methods of total body irradiation within the context of a clinical department adopting a paediatric cohort with no existing technique. An extensive review of the literature was conducted using PubMed, Science Direct, Google Scholar, and Clinicians Knowledge Network. Articles were limited to nonhelical tomotherapy, nonparticle therapies, and those using hyperfractionated regimes. Total marrow irradiation was excluded because of national treatment and trial limitations. Of the numerous patient positioning methods present within the literature, the most comfortable and reproducible positioning methods for total body irradiation include both supine and the supine and/or prone combination. These positions increased stability and patient comfort during treatment, while also facilitating computed tomography data acquisition at the simulation stage. Ideally, dose calculations should be performed using a three-dimensional treatment planning system and quality assurance procedures that include in vivo dosimetry measurements. The available literature also suggests inhomogeneity correction factors and intensity modulation are superior to conventional open field techniques and should be implemented within developing protocols. Dynamic machine dose modulation is suggested to reduce department impact, removing the need for tissue compensators and accessory shielding devices, while providing significant improvements to treatment time and dose accuracy. Further long-term survival and intensity modulation studies are warranted, including direct comparisons of both dose modulation and treatment efficiency. 相似文献
49.
50.
《Journal of vascular and interventional radiology : JVIR》2020,31(5):760-768.e1
PurposeTo investigate dynamic variables obtained from retrospective computed tomography angiography for ability to predict thoracic endovascular aortic repair (TEVAR) outcomes in patients with complicated type B aortic dissection (cTBAD).Materials and MethodsSeventy-nine patients with cTBAD who received TEVAR from March 2009 to June 2018 were retrospectively enrolled. Relative true lumen area (r-TLA) was computed at the level of tracheal bifurcation every 5% of all R-R intervals. Parameters that reflect the state of intimal motion were evaluated, including difference between maximum and minimum r-TLA (D-TLA) and true lumen collapse. The endpoints comprised early (≤ 30 days) and late (> 30 days) outcomes after intervention.ResultsOverall early mortality rate was 13.9% (11/79), and early adverse events rate was 24.1% (19/79). Patients who received TEVAR within 2 days of symptom onset demonstrated the worst outcomes. A longer time of r-TLA < 25% in 1 cardiac cycle (P = .049) and larger D-TLA (P < .001) were correlated to an increased early death. In addition, D-TLA was an independent predictor of early mortality. Area under the curve of D-TLA was 0.849 (95% confidence interval 0.730–0.967) for predicting early mortality and 0.742 (95% CI 0.611–0.873) for predicting early adverse events. Survival and event-free survival rates during follow-up were decreased in the D-TLA > 21.5% group compared with the D-TLA ≤ 21.5% group (all P < .001).ConclusionsLarger D-TLA is correlated with worse postoperative outcomes and might be a crucial parameter for future risk stratification in patients with cTBAD. 相似文献