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31.
Ljungberg K Hassan MS Islam MN Siddiqui MA Aziz MM Wahren B Islam KB Leitner T 《AIDS research and human retroviruses》2002,18(9):667-670
We analyzed the genetic diversity of HIV-1 circulating in Bangladesh by direct sequencing and subsequent phylogenetic analysis of the V3 region of the env gene and p17 fragment of the gag gene from nine unrelated patients. The sequences from one sample grouped into subtype A, five samples grouped into subtype C, and one grouped into subtype G. In addition, two patients appeared to be infected with different recombinant viruses consisting of subtype A and unclassifiable viral sequences. Epidemiological analysis revealed heterosexual transmission in the majority of cases. Furthermore, most subjects had a history of traveling, either to India or to the Arabian Peninsula. This study shows that several HIV-1 subtypes are circulating in Bangladesh, and we conclude that there must have been several introductions of HIV-1 into the Bangladeshi population. 相似文献
32.
Aminul Haq Harry Rakowski Ronald Baigrie Peter McLaughlin Robert Burns Hariwan Tihal David Hilton David Feiglin 《The American journal of cardiology》1982,49(2):439-444
The response to vasodilator therapy was assessed in 12 patients with chronic severe congestive heart failure refractory to conventional treatment. Cardiac output and intraarterial and pulmonary capillary wedge pressures were recorded continuously to assess the hemodynamic response to the vasodilators used. Control and post-treatment M mode echocardiograms and radionuclide angiograms were obtained to assess the change in left ventricular size and ejection fraction concurrent with the hemodynamic improvement. Despite a 33 percent decrease in pulmonary capillary wedge pressure (p < 0.001) and a 35 percent increase in cardiac index (p < 0.001), no significant change occurred in left ventricular end-diastolic or end-systolic chamber size on echocardiography or in ejection fraction measured with radionuclide angiography.In this study, M mode echocardiography and radionuclide angiography were of no value in monitoring the actual hemodynamic response to vasodilator therapy in this group of patients with a left ventricular ejection fraction of less than 30 percent. 相似文献
33.
BACKGROUND: Patients with elevated troponin are at high risk of adverse outcomes, future cardiac events, and are more likely to have hemodynamically significant coronary artery stenoses. Elevated troponin T (cTnT) in patients with poor renal function portends a poor prognosis; however, findings of significant coronary artery disease (CAD) by coronary angiography have not been demonstrated in patients with poor renal function and elevated cTnT. HYPOTHESIS: The purpose of this study was to correlate the angiographic findings of patients with elevated cTnT with respect to renal function in patients with nondialysis-dependent renal insufficiency. METHODS: We retrospectively identified 342 patients with elevated cTnT who underwent coronary angiography in the setting of acute coronary syndrome. Patients were divided into poor (< 40 ml/min) and normal (> 40 ml/min) renal function by measuring their glomerular filtration rate. Our primary outcome was CAD stenosis, defined as epicardial stenosis > or = 70%. Secondary outcomes were rates of contrast nephropathy, initiation of hemodialysis, revascularization, length of stay (LOS), and in-hospital mortality. RESULTS: There was no significant difference in the prevalence of CAD between patients who had positive cTnT with poor renal function versus patients with positive cTnT and normal renal function (87.1 vs. 89.7%, p = 0.54). This finding persisted after stratifying by age. Patients with impaired renal function had a higher mortality, longer LOS, and a higher rate contrast nephropathy requiring hemodialysis. CONCLUSION: The association between elevated cTnT and significant CAD stenosis does not vary with renal function. 相似文献
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35.
Alexandra L. Coria Tracy L. Rabin Amy R.L. Rule Heather Haq James C. Hudspeth Leah Ratner Ingrid Walker-Descartes 《Journal of general internal medicine》2022,37(1):217
The COVID-19 pandemic plunged hospital systems into resource-deprived conditions unprecedented since the 1918 flu pandemic. It brought forward concerns around ethical management of scarcity, racism and distributive justice, cross-disciplinary collaboration, provider wellness, and other difficult themes. We, a group of medical educators and global health educators and clinicians, use the education literature to argue that experience gained through global health activities has greatly contributed to the effectiveness of the COVID-19 pandemic response in North American institutions. Support for global health educational activities is a valuable component of medical training, as they build skills and perspectives that are critical to responding to a pandemic or other health system cataclysm. We frame our argument as consideration of three questions that required rapid, effective responses in our home institutions during the pandemic: How can our health system function with new limitations on essential resources? How do we work at high intensity and volume, on a new disease, within new and evolving systems, while still providing high-quality, patient-centered care? And, how do we help personnel manage an unprecedented level of morbidity and mortality, disproportionately affecting the poor and marginalized, including moral difficulties of perceived care rationing?KEY WORDS: global health education, global health, medical education, COVID-19 相似文献
36.
Abbas Khan Jianjun Gui Waqar Ahmad Inamul Haq Marukh Shahid Awais Ahmed Khan Abdullah Shah Arsala Khan Liaqat Ali Zeeshan Anwar Muhammad Safdar Jehad Abubaker N. Nizam Uddin Liqiang Cao Dong-Qing Wei Anwar Mohammad 《RSC advances》2021,11(48):30132
Continuing reports of new SARS-CoV-2 variants have caused worldwide concern and created a challenging situation for clinicians. The recently reported variant B.1.618, which possesses the E484K mutation specific to the receptor-binding domain (RBD), as well as two deletions of Tyr145 and His146 at the N-terminal binding domain (NTD) of the spike protein, must be studied in depth to devise new therapeutic options. Structural variants reported in the RBD and NTD may play essential roles in the increased pathogenicity of this SARS-CoV-2 new variant. We explored the binding differences and structural-dynamic features of the B.1.618 variant using structural and biomolecular simulation approaches. Our results revealed that the E484K mutation in the RBD slightly altered the binding affinity through affecting the hydrogen bonding network. We also observed that the flexibility of three important loops in the RBD required for binding was increased, which may improve the conformational optimization and consequently binding of the new variant. Furthermore, we found that deletions of Tyr145 and His146 at the NTD reduced the binding affinity of the monoclonal antibody (mAb) 4A8, and that the hydrogen bonding network was significantly affected consequently. This data show that the new B.1.618 variant is an antibody-escaping variant with slightly altered ACE2–RBD affinity. Moreover, we provide insights into the binding and structural-dynamics changes resulting from novel mutations in the RBD and NTD. Our results suggest the need for further in vitro and in vivo studies that will facilitate the development of possible therapies for new variants such as B.1.618.This study explored the binding patterns of the wild type and B.1.618 variant using which revealed that the B.1.618 variant possess a stronger binding affinity for the host ACE2 and escape the neutralizing antibodies. 相似文献
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38.
Dynamic continuous measurement of the curvature of the lumbar spine is technically difficult but could provide important information about the functions of the spine. A new measurement system using a ribbon of specifically modified fibre-optic sensors was attached to the back and used to dynamically measure lumbar surface curvature during flexion and lifting. Reliability of the collected data and comparison to a video-based system were investigated in thirteen participants for curvature of both the lower and whole lumbar spine. The coefficients of multiple correlation of repeated measurements of curvature–time curves were found to be high, 0.97–0.98, and all measurements were as reliable as data obtained by the video method (0.93–0.97). Root mean square error values were below 2.5° for the fibre-optic system. Reattachment reliability was found to be excellent (0.91–0.97) as were comparisons to a video-based method (0.84–0.95). It is concluded that the fibre-optic motion analysis system is capable of reliably measuring sagittal lumbar curvature across time and offers the ability to provide information regarding sequencing and relative motion between specific regions of the lumbar spine. 相似文献
39.
Abdul Wahab Rizwan Ul Haq Aftab Ahmed Rafeeq Alam Khan Mohsin Raza 《Phytotherapy research : PTR》2009,23(2):153-158
The purpose of this study was to investigate the anticonvulsant activity of the volatile oil of nutmeg, the dried seed kernel of Myristica fragrans Houtt, using well‐established animal seizure models and to evaluate its potential for acute toxicity and acute neurotoxicity. The volatile oil of nutmeg (nutmeg oil) was tested for its effects in maximal electroshock, subcutaneous pentylenetetrazole, strychnine and bicuculline seizure tests. All the experiments were performed at the time of peak effect of nutmeg oil. Nutmeg oil showed a rapid onset of action and short duration of anticonvulsant effect. It was found to possess significant anticonvulsant activity against electroshock‐induced hind limb tonic extension. It exhibited dose dependent anticonvulsant activity against pentylenetetrazole‐induced tonic seizures. It delayed the onset of hind limb tonic extensor jerks induced by strychnine. It was anticonvulsant at lower doses, whereas weak proconvulsant at a higher dose against pentylenetetrazole and bicuculline induced clonic seizures. Nutmeg oil was found to possess wide therapeutic margin, as it did not induce motor impairment when tested up to 600 µL/kg in the inverted screen acute neurotoxicity test. Furthermore, the LD50 (2150 µL/kg) value was much higher than its anticonvulsant doses (50–300 µL/kg). The results indicate that nutmeg oil may be effective against grand mal and partial seizures, as it prevents seizure spread in a set of established animal models. Slight potentiation of clonic seizure activity limits its use for the treatment of myoclonic and absence seizures. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
40.
Afzal Haq Asif Mahendra S. Mahajan Nagaraja Sreeharsha Vikas V. Gite Bandar E. Al-Dhubiab Feroze Kaliyadan Shivakumar H. Nanjappa Girish Meravanige Dalal Mishary Aleyadhy 《Materials》2022,15(6)
The present investigation demonstrates renewable cardanol-based polyol for the formulation of nanocomposite polyurethane (PU) coatings. The functional and structural features of cardanol polyol and nanoparticles were studied using FT-IR and 1H NMR spectroscopic techniques. The magnetic hydroxyapatite nanoparticles (MHAPs) were dispersed 1–5% in PU formulations to develop nanocomposite anticorrosive coatings. An increase in the strength of MHAP increased the anticorrosive performance as examined by immersion and electrochemical methods. The nanocomposite PU coatings showed good coating properties, viz., gloss, pencil hardness, flexibility, cross-cut adhesion, and chemical resistance. Additionally, the coatings were also studied for surface morphology, wetting, and thermal properties by scanning electron microscope (SEM), contact angle, and thermogravimetric analysis (TGA), respectively. The hydrophobic nature of PU coatings increased by the addition of MHAP, and an optimum result (105°) was observed in 3% loading. The developed coatings revealed its hydrophobic nature with excellent anticorrosive performance. 相似文献