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71.
Diaphragmatic weakness in chronic obstructive pulmonary disease (COPD) is ascribed to hyperinflation-induced diaphragm shortening as well as impairment in cellular and subcellular structures. Although phrenic neuropathy is known to cause diaphragmatic weakness, phrenic neuropathy is rarely considered in COPD. This work aimed at assessing phrenic nerve conduction in COPD and its relation to radiographic hyperinflation and pulmonary function. Patients and methods: Forty COPD patients were evaluated. Radiographic parameters of lung hyperinflation were measured on postero-anterior and lateral chest x-ray films. Flow volume loop parameters were obtained from all patients. Motor conduction study of the phrenic nerves was performed and potentials were recorded over the xiphoid process and the ipsilateral 7th intercostal space. Twenty-seven healthy subjects were enrolled as controls. Results: Parameters of phrenic nerve conduction differed significantly in patients compared to controls. Phrenic nerve abnormalities were detected in 17 patients (42.5%). Electrophysiological measures correlated with diaphragmatic angle of depression on lateral view films and with lung height on postero-anterior films. They did not correlate with the flow volume loop data or disease severity score. Conclusion: Phrenic nerve conduction abnormality is an appreciated finding in COPD. Nerve stretching associated with diaphragmatic descent can be a suggested mechanism for nerve lesion. The presence of phrenic neuropathy may be an additional contributing factor to diaphragmatic dysfunction in COPD patients. 相似文献
72.
Peri‐implant soft tissue inflammatory parameters and crestal bone loss among waterpipe (narghile) smokers and never‐smokers with and without type 2 diabetes mellitus 下载免费PDF全文
Zeyad H. Al‐Sowygh Abdulaziz A. Al‐Kheraif Zohaib Akram Fahim Vohra Fawad Javed 《Journal of periodontology》2018,89(6):645-652
1 Background
Peri‐implant soft tissue inflammatory parameters and crestal bone loss (CBL) among waterpipe smokers (WS) with and without type 2 diabetes mellitus (T2DM) remains uninvestigated. The aim of the present study was to assess peri‐implant soft tissue inflammatory parameters and CBL among WS and never smokers (NS) with and without T2DM.2 Methods
Demographic data and information regarding duration of implants in function, daily frequency of smoking, duration and treatment of T2DM, and daily toothbrushing was collected using a questionnaire. Peri‐implant plaque index (PI), bleeding on probing (BOP), probing depth (PD) ≥4 mm, CBL, and hemoglobin A1c (HbA1c) levels were assessed in all individuals. Level of significance was set at 5%.3 Results
Seventy‐nine male individuals (39 patients with T2DM [20 WS and 19 NS] and 40 systemically healthy individuals [21 WS smokers and 19 NS]) were included. The mean age was comparable among individuals in all groups. The mean HbA1c levels were significantly higher among patients with T2DM compared to controls (P < 0.01). Peri‐implant PI, BOP, PD, and CBL were comparable among WS and NS with T2DM. Among patients without T2DM, PI (P < 0.05), PD ≥4 mm (P < 0.05) and mesial and distal CBL (P < 0.05) were significantly higher in WS than NS. Among individuals without T2DM, BOP was significantly higher among NS (P < 0.05) than WS. In patients with T2DM, BOP was comparable among WS and NS.4 Conclusions
Peri‐implant soft tissue inflammatory parameters and CBL were comparable among WS and NS with T2DM. Among individuals without T2DM, these parameters were worse among WS than NS. 相似文献73.
Mydin MI Dimitrakakis G Younis J Nowell J Athanasiou T Kourliouros A 《Interactive Cardiovascular and Thoracic Surgery》2012,15(1):109-114
Optimal thromboprophylaxis following bioprosthetic aortic valve replacement (AVR) remains controversial. The main objective, which is the effective prevention of central nervous or peripheral embolic events, especially in the early postoperative period, will have to be weighed against the haemorrhagic risk that is associated with the utilization of different antithrombotic regimes. Most governing bodies in cardiovascular medicine have issued recommendations on thromboprophylaxis after the surgical implantation of aortic bioprostheses. However, the level of evidence to support these recommendations remains low, largely due to the inherent limitations of conducting appropriately randomized and adequately powered clinical research in this area. It is apparent from the recent surveys and large registries that there is a great variability in antithrombotic practice at an institutional or individual-clinician level reflecting this controversy and the lack of robust evidence. While organizational, financial or conceptual limitations could hinder the conduct and availability of conclusive research on optimal thromboprophylaxis after aortic bioprosthesis, it is imperative that all evidence is presented in a systematic way in order to assist the decision-making for the modern clinician. In this review, we provide an outline of the current recommendations for thromboprophylaxis, followed by a comprehensive and analytical presentation of all comparative studies examining anticoagulation vs. antiplatelet therapy after bioprosthetic AVR. 相似文献
74.
Ahamed MB Aisha AF Nassar ZD Siddiqui JM Ismail Z Omari SM Parish CR Majid AM 《Nutrition and cancer》2012,64(1):89-99
Cat's whiskers (Orthosiphon stamineus) is commonly used as Java tea to treat kidney stones including a variety of angiogenesis-dependent diseases such as tumorous edema, rheumatism, diabetic blindness, and obesity. In the present study, antitumor potential of standardized 50% ethanol extract of O. stamineus leaves (EOS) was evaluated against colorectal tumor in athymic mice and antiangiogenic efficacy of EOS was investigated in human umbilical vein endothelial cells (HUVEC). EOS at 100 mg/kg caused 47.62?± 6.4% suppression in tumor growth, while at 200 mg/kg it caused 83.39 ± 4.1% tumor regression. Tumor histology revealed significant reduction in extent of vascularization. Enzyme-linked immunosorbent assay showed EOS (200 mg/kg) significantly reduced the vascular endothelial growth factor (VEGF) level in vitro (211?± 0.26 pg/ml cell lysate) as well as in vivo (90.9 ± 2 pg/g tissue homogenate) when compared to the control (378 ± 5 and 135.5 ± 4 pg, respectively). However, EOS was found to be noncytotoxic to colon cancer and endothelial cells. In vitro, EOS significantly inhibited the migration and tube formation of human umbilical vein endothelial cells (HUVECs). EOS suppressed VEGF-induced phosphorylation of VEGF receptor-2 in HUVECs. High performance liquid chromatography (HPLC) analysis of EOS showed high rosmarinic acid contents, whereas phytochemical analysis revealed high protein and phenolic contents. These results demonstrated that the antitumor activity of EOS may be due to its VEGF-targeted antiangiogenicity. 相似文献
75.
Dr. Zeyad K. Sharaiha MD Jeffrey W. Sackman BA Dr. David Y. Graham MD 《Digestive diseases and sciences》1983,28(9):827-832
Phenolphthalein is an odorless, tasteless compound, poorly soluble in water, but readily soluble in alcohol or ether. Although its laxative activity was discovered in 1902, the mechanism of action remains unclear. Phenolphthalein has been found to be an ineffective laxative in both jaundiced patients and in experimental animals with ligated common bile ducts. In contrast to the poor solubility of phenolphthalein, phenolphthalein glucuronide is highly water-soluble. In addition, phenolphthalein glucuronide is found in bile following oral phenolphthalein administration, suggesting an enterohepatic circulation. We compared the effect of phenolphthalein and phenolphthalein glucuronide on net water absorption of the ileum and colon of Sprague-Dawley rats using a single-pass perfusion technique. Perfusion of phenolphthalein (10 mg/dl in 154 mM NaCl with 0.5% ethanol and 0.1 g/l gum arabic) resulted in significantly reduced water absorption in both the ileum and colon (66% and 64%, respectively, P less than 0.05). In contrast, phenolphthalein glucuronide did not have a significant effect on net water flux compared to control perfusion in either the ileum or colon. In the ileum only 77 +/- 3% and colon 71 +/- 1.2% of the phenolphthalein infused was recovered, suggesting that much of the infused phenolphthalein was absorbed. In contrast there was no evidence of absorption of phenolphthalein glucuronide, as 98.9 +/- 1.2% was recovered from ileal and colon perfusions. Phenolphthalein glucuronide is not the active form of phenolphthalein, although it may be an effective laxative after deconjugation by colonic bacteria. 相似文献
76.
77.
78.
Carmen W. E. Embregts Elmoubashar A. B. A. Farag Devendra Bansal Marjan Boter Anne van der Linden Vincent P. Vaes Ingeborg van Middelkoop-van den Berg Jeroen. IJpelaar Hisham Ziglam Peter V. Coyle Imad Ibrahim Khaled A. Mohran Muneera Mohammed Saleh Alrajhi Md. Mazharul Islam Randa Abdeen Abdul Aziz Al-Zeyara Nidal Mahmoud Younis Hamad Eid Al-Romaihi Mohammad Hamad J. AlThani Reina S. Sikkema Marion P. G. Koopmans Bas B. Oude Munnink Corine H. GeurtsvanKessel 《Viruses》2022,14(12)
Rabies virus (RABV) has a broad host range and infects multiple cell types throughout the infection cycle. Next-generation sequencing (NGS) and minor variant analysis are powerful tools for studying virus populations within specific hosts and tissues, leading to novel insights into the mechanisms of host-switching and key factors for infecting specific cell types. In this study we investigated RABV populations and minor variants in both original (non-passaged) samples and in vitro-passaged isolates of various CNS regions (hippocampus, medulla oblongata and spinal cord) of a fatal human rabies case, and of multiple CNS and non-CNS tissues of experimentally infected mice. No differences in virus populations were detected between the human CNS regions, and only one non-synonymous single nucleotide polymorphism (SNP) was detected in the fifth in vitro passage of virus isolated from the spinal cord. However, the appearance of this SNP shows the importance of sequencing newly passaged virus stocks before further use. Similarly, we did not detect apparent differences in virus populations isolated from different CNS and non-CNS tissues of experimentally infected mice. Sequencing of viruses obtained from pharyngeal swab and salivary gland proved difficult, and we propose methods for improving sampling. 相似文献
79.
80.
One hundred five single-rooted teeth were prepared and filled with ten commercially available root canal paste sealers. Five teeth were filled with only gutta-percha points, fifty teeth were filled with a particular cement alone, and the rest of the teeth were filled with a particular cement in conjunction with gutta-percha points. It was found that the gutta-percha point alone is not sufficient for sealing the periapical foramen; nor are N2 (Sargenti), Riebler's paste, and the iodoform paste. In general, it was found that the combination of gutta-percha and cement is more effective in sealing the periapical foramen. Polycarboxylate cement used in this investigation, although it does not meet all the requirements of a good root canal sealant, was found to yield promising results. 相似文献