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排序方式: 共有970条查询结果,搜索用时 140 毫秒
61.
Celiktas M Birbiçer H Aikimbaev K Ozbek H Akgül E Binokay F 《Acta radiologica (Stockholm, Sweden : 1987)》2003,44(5):494-497
Purpose:
To assess the hemodynamic changes in the upper extremity arteries after sympathetic ganglion blockade (SGB) by using spectral Doppler parameters and to determine the applicability of these parameters for the evaluation of SGB efficacy. Material and Methods:
Spectral Doppler parameters (peak systolic velocity (PSV), end diastolic velocity (EDV), mean velocity (mean V), flow volume, resistive and pulsatility indices (RI, PI), inner arterial diameters (intima to intima) (D) with simultaneous recordings of heart rate (HR), systolic and diastolic blood pressures and upper extremity surface temperature changes) were recorded before and 5 min after during the first, fifth and tenth SGB procedures. Results:
SGB induced an increase in skin temperature in the ipsilateral hand and persistent dilatation of the radial diameter accompanied by reduction of RI and PI in the radial and third digital arteries in all patients. Conclusion:
Hemodynamic changes assessed by spectral Doppler parameters could be used as sensitive and objective measurements of peripheral sympathetic nervous activity and vascular tonus, and may confirm a successfully performed SGB. 相似文献
To assess the hemodynamic changes in the upper extremity arteries after sympathetic ganglion blockade (SGB) by using spectral Doppler parameters and to determine the applicability of these parameters for the evaluation of SGB efficacy. Material and Methods:
Spectral Doppler parameters (peak systolic velocity (PSV), end diastolic velocity (EDV), mean velocity (mean V), flow volume, resistive and pulsatility indices (RI, PI), inner arterial diameters (intima to intima) (D) with simultaneous recordings of heart rate (HR), systolic and diastolic blood pressures and upper extremity surface temperature changes) were recorded before and 5 min after during the first, fifth and tenth SGB procedures. Results:
SGB induced an increase in skin temperature in the ipsilateral hand and persistent dilatation of the radial diameter accompanied by reduction of RI and PI in the radial and third digital arteries in all patients. Conclusion:
Hemodynamic changes assessed by spectral Doppler parameters could be used as sensitive and objective measurements of peripheral sympathetic nervous activity and vascular tonus, and may confirm a successfully performed SGB. 相似文献
62.
Bolduc S Upadhyay J Restrepo R Sherman C Farhat W Bägli DJ McLorie GA Khoury AE El Ghoneimi A 《BJU international》2003,91(7):678-682
OBJECTIVE: To compare the diagnostic imaging findings with the histological lesions in upper pole nephrectomy (UPN) specimens of duplex system ureteroceles, using renal ultrasonography (US) and nuclear renal scintigraphy. PATIENTS AND METHODS: Between 1992 and 2000, 86 patients with a ureterocele in a duplex system underwent surgery. The results from US were reviewed in 84 patients by a radiologist, for echogenicity, parenchymal thinning and hydronephrosis; 77 nuclear renal scans describing the differential function of the upper poles were also reviewed. Fifty-five patients underwent UPN (25 antenatal, 30 postnatal; 18 intravesical, 37 extravesical) and the specimens were available for independent review by a pathologist, describing five histological categories, i.e. chronic interstitial inflammation, fibrosis, tubular atrophy, glomerulosclerosis and dysplasia. Histological lesions were categorized as severe (> 25%) or minimal (相似文献
63.
《Journal of pediatric urology》2020,16(1):33.e1-33.e8
64.
《Drug and chemical toxicology》2013,36(3):316-324
As recommended by OECD Guidelines, percutaneous penetration studies consider intact skin, but rarely injured skin. Recent years have witnessed a growing concern for these two types of dermal exposure in the industry, particularly in the nuclear industry. The aim of this study was to show that a method based on an in vitro device can be used to realistically assess how skin-barrier alterations caused by occupational accidents can modify the percutaneous penetration and distribution of radionuclides, particularly uranium. Wounds encountered in the nuclear industry (i.e., nitric acid burns and abrasion) were simulated on hairless rat skin. Skin-barrier alterations were characterized by means of a histological study and by measuring transepidermal water loss (TEWL) and skin thickness. The percutaneous penetration of uranyl nitrate through intact or injured skin biopsies was then measured in vitro. The maximum uranium flux values obtained for intact skin, skin abrasion with stratum corneum removal, and skin exposed to 2 N HNO3, 5 N HNO3, and 14 N HNO3 were, respectively, 0.6?±?0.02, 1.2?±?0.03, 1.2?±?0.04, 42.0?±?1.0, and 174.0?±?8.7?ng.cm?2.h?1. These results demonstrated that the percutaneous absorption of uranium increased with the increased impairment of the stratum corneum. TEWL, combined with maximum uranium flux values measured in vitro, yielded a good prediction of the percutaneous penetration of uranium through injured skin, previously observed in vivo. To conclude, this in vitro assay provides a conservative estimate of the percutaneous diffusion of uranium through intact or injured skin, making it a good alternative method for toxicological studies and risk assessments. 相似文献
65.
目的:探讨枯草杆菌屎肠球菌二联活菌制剂(商品名:美常安)对急性肝衰竭(AHF)大鼠肠道微生态失调的调节作用。方法:用D-氨基半乳糖(D-gal)1.2 g/kg腹腔注射制成AHF模型。将实验动物分为对照组、模型组、治疗组,分别检测肠道菌群变化和内毒素含量。结果:经过美常安治疗2周后,大鼠肠道内有益菌含量明显上升,有害菌含量下降,肠道菌群比例恢复正常,血中内毒素含量降低。结论:美常安通过对AHF大鼠肠道微生态失调的直接调节作用,间接的起到了保肝护肝的作用,对于AHF疾病的本身也起到了积极的治疗作用。 相似文献
66.
R. A. Montgomery S. Katznelson W. I. Bry A. A. Zachary J. Houp J. M. Hiller S. Shridharani D. John A. L. Singer D. L. Segev 《American journal of transplantation》2008,8(10):2163-2168
Providing transplantation opportunities for patients with incompatible live donors through kidney paired donation (KPD) is seen as one of the important strategies for easing the crisis in organ availability. It has been estimated that an additional 1000—2000 transplants per year could be accomplished if a national KPD program were implemented in the United States. While most of these transplants could be arranged within the participants' local or regional area, patients with hard‐to‐match blood types or broad HLA sensitization would benefit from matching across larger geographic areas. In this case, either patients or organs would need to travel in order to obtain maximum benefit from a national program. In this study, we describe how a triple KPD enabled a highly sensitized patient (PRA 96%) to receive a well‐matched kidney from a live donor on the opposite coast. The kidney was removed in San Francisco and transported to Baltimore where it was reperfused 8 h later. The patient had prompt function and 1 year later has a serum creatinine of 1.1 mg/dl. This case provides a blueprint for solving some of the complexities that are inherent in the implementation of a national KPD program in a large country like the United States. 相似文献
67.
Maria Heloisa M. Shimizu Rildo A. VolpiniAna Carolina de Bragança Renata CamposDaniele Canale Talita R. SanchesLúcia Andrade Antonio C. Seguro 《Experimental gerontology》2013
The aim of this study was to evaluate the effects of N-acetylcysteine (NAC) on renal function, as well as on sodium and water transporters, in the kidneys of aged rats. Normal, 8-month-old male Wistar rats were treated (n = 6) or not (n = 6) with NAC (600 mg/L in drinking water) and followed for 16 months. At the end of the follow-up period, we determined inulin clearance, serum thiobarbituric acid reactive substances (TBARS), serum cholesterol, and urinary phosphate excretion. In addition, we performed immunohistochemical staining for p53 and for ED-1-positive cells (macrophages/monocytes), together with Western blotting of kidney tissue for NKCC2, aquaporin 2 (AQP2), urea transporter A1 (UT-A1) and Klotho protein. At baseline, the two groups were similar in terms of creatinine clearance, proteinuria, cholesterol, and TBARS. At the end of the follow-up period, NAC-treated rats presented greater inulin clearance and reduced proteinuria, as well as lower serum cholesterol, serum TBARS, and urinary phosphate excretion, in comparison with untreated rats. In addition, NAC-treated rats showed upregulated expression of NKCC2, AQP2, and UT-A1; elevated Klotho protein expression, low p53 expression, and few ED-1 positive cells. In conclusion, we attribute these beneficial effects of NAC (the significant improvements in inulin clearance and in the expression of NKCC2, AQP2, and UT-A1) to its ability to decrease oxidative stress, inhibit p53 expression, minimize kidney inflammation, and stimulate Klotho expression. 相似文献
68.
Alexandre Marchand Daisy Roy Sarah A. Monsheimer Jennifer Lewis Magnus Ericsson 《Drug testing and analysis》2022,14(4):724-732
The World Anti-Doping Agency (WADA) prohibits athletes from using recombinant growth hormone (GH). The validated method used in antidoping laboratories for the direct detection of exogenous GH in serum requires two immunoluminometric assays (ILMAs): The first mainly measures the concentration of the full-length (22 kDa) form of GH (recGH), and the second measures concentrations of multiple GH fragments produced by the pituitary gland (22 kDa, 20 kDa and other forms) (pitGH). The tube-by-tube analysis is laborious. A recent development opened new possibilities to simplify the detection of recGH in serum: multiplexed immunoassays that detect multiple targets in a single well of a 96-well plate using an ELISA-like procedure with high sensitivity. Our aim was to evaluate this technology by developing a customized assay for GH detection. One pair of antibodies with specificities similar to those of the recGH assay and one pair of antibodies compatible with pitGH detection were selected for a single duplex assay. Forty-eight serum samples (negative athlete samples and positive samples following GH administration) were analyzed using the two methods. The microplate duplex assay discriminated between the negative athlete samples and the positive controls, although the rec/pit ratios from the duplex assay were lower than those obtained with the ILMAs. This new assay would offer a modern alternative to ILMAs, with fewer analytical steps and a smaller sample volume. However, an adaptation of the decision limits seems mandatory. 相似文献
69.
Jyotsna Murthy Ramesh Babu Padmasani Venkat Ramanan 《Indian Journal of Plastic Surgery》2008,41(1):76-78
The Baller-Gerold syndrome is a rare syndrome with very few cases published in literature. Craniosynostosis and radial aplasia are striking features, easy to diagnose. However, there are many differential diagnoses. Often, the question raised is whether the Baller-Gerald syndrome is a distinct entity. We report a patient with findings of craniosynostosis and radial aplasia consistent with the diagnosis of the Baller-Gerold syndrome. Genotypic heterogeneity could possibly underlie the phenotypic variability exhibited by these cases. 相似文献
70.
Thomas Zeller MD Robert F. Bonvini MD Sebastian Sixt MD 《Catheterization and cardiovascular interventions》2008,71(7):995-999
Currently, angiography is still considered to be the gold standard for the diagnosis of a renal artery stenosis (RAS). However, angiography is invasive and carries the potential risk of haematoma, pseudoaneurysm, contrast agent induced nephropathy, and athermanous embolization. Color‐coded duplex ultrasound is a noninvasive frequently repeatable bed‐side examination and is currently the only diagnostic method to reliably differentiate between a hemodynamically relevant or irrelevant stenosis using the side‐to‐side difference of the intrarenal resistance index (RI). There is a highly specific correlation between a side difference of the RI of >0.05 and an at least 70% angiographic diameter stenosis. All other duplex parameters like a peak systolic flow velocity >200 cm/sec or a renal aortic flow velocity ratio >3.5 are correlated to a 50 or 60% angiographic diameter stenosis and offer therefore indeed a high sensitivity in terms of detecting a RAS; however, the specificity detecting a hemodynamically relevant RAS is low. Provided that duplex ultrasound is performed by an experienced physician with an adequate machine it should be the preferred imaging method. The present article gives an overview about the literature related to duplex based diagnosis of RAS and as a follow‐up diagnostic procedure following RAS revascularization. © 2008 Wiley‐Liss, Inc. 相似文献