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101.
The pulmonary flow pattern was analysed by pulsed Doppler in 77 normal neonates, at < 48 hours (36 subjects), 49 to 96 hours (25 subjects) and 97 to 148 hours (16 subjects). From the flow velocity spectrum, using an built in computer system, the acceleration time and the ejection time were measured, and the ratio was calculated. This ratio was 0.24 +/- 0.08 in the subjects within 48 hours whereas this ratio was 0.53 +/- 0.11 in the subjects above 97 hours; thus the ratio increased with age. We noticed that the ratio obtained from the pulsed Doppler is useful in assessing the pulmonary vascular status, even in neonates. 相似文献
102.
Increased calcium uptake in vascular tissue, leading to elevated cytosolic free calcium has been implicated in the pathophysiology of hypertension. This study examined the effect of oral heparin on systolic blood pressure, platelet cytosolic free calcium and aortic calcium uptake in spontaneously hypertensive and normotensive Wistar-Kyoto rats. Starting at age 12 weeks, each strain of rats were divided into 2 groups (6 animals in each group); the control group was placed on H2O (100%) and the experimental group was placed on H2O with heparin (0.5 mg sodium heparin/ml H2O) for a period of nine weeks. At 21 weeks, systolic blood pressure, platelet cytosolic free calcium and aortic calcium uptake were significantly higher in spontaneously hypertensive rats on water compared with spontaneously hypertensive rats on heparin and Wistar-Kyoto rats on water and on heparin. Oral heparin treatment normalized the elevated platelet cytosolic free calcium, aortic calcium uptake and systolic blood pressure in spontaneously hypertensive rats but had no effect on Wistar-Kyoto rats. Heparin also prevented onset of adverse renal vascular changes observed in spontaneously hypertensive rats. Oral heparin treatment did not cause abnormal hematological, biochemical or pathological changes in rats. 相似文献
103.
Austin BP Nair VA Meier TB Xu G Rowley HA Carlsson CM Johnson SC Prabhakaran V 《Journal of Alzheimer's disease : JAD》2011,26(Z3):123-133
The role of hypoperfusion in Alzheimer's disease (AD) is a vital component to understanding the pathogenesis of this disease. Disrupted perfusion is not only evident throughout disease manifestation, it is also demonstrated during the pre-clinical phase of AD (i.e., mild cognitive impairment) as well as in cognitively healthy persons at high-risk for developing AD due to family history or genetic factors. Studies have used a variety of imaging modalities (e.g., SPECT, MRI, PET) to investigate AD, but with its recent technological advancements and non-invasive use of blood water as an endogenous tracer, arterial spin labeling (ASL) MRI has become an imaging technique of growing popularity. Through numerous ASL studies, it is now known that AD is associated with both global and regional cerebral hypoperfusion and that there is considerable overlap between the regions implicated in the disease state (consistently reported in precuneus/posterior cingulate and lateral parietal cortex) and those implicated in disease risk. Debate exists as to whether decreased blood flow in AD is a cause or consequence of the disease. Nonetheless, hypoperfusion in AD is associated with both structural and functional changes in the brain and offers a promising putative biomarker that could potentially identify AD in its pre-clinical state and be used to explore treatments to prevent, or at least slow, the progression of the disease. Finally, given that perfusion is a vascular phenomenon, we provide insights from a vascular lesion model (i.e., stroke) and illustrate the influence of disrupted perfusion on brain structure and function and, ultimately, cognition in AD. 相似文献
104.
First Report of Dramatic Tumor Responses with Ramucirumab and Paclitaxel After Progression on Pembrolizumab in Two Cases of Metastatic Gastroesophageal Adenocarcinoma 下载免费PDF全文
Sakti Chakrabarti Haidong Dong Harshita R. Paripati Helen J. Ross Harry H. Yoon 《The oncologist》2018,23(7):840-843
Checkpoint inhibitors targeted at programmed cell death‐1 receptor (PD‐1) and its ligand (PD‐L1) can result in significant benefit to a small proportion of patients with cancer, including those with tumors of the stomach and gastroesophageal junction. These drugs are now approved for several solid tumors, including the recent accelerated approval of pembrolizumab for gastroesophageal adenocarcinomas in the third‐line setting and beyond based on the KEYNOTE‐059 phase II trial. Data are lacking on the efficacy of chemotherapy after progression on PD‐1 blockade in metastatic gastroesophageal adenocarcinoma. This report describes the exceptional response of two patients who received ramucirumab plus paclitaxel after progressive disease on pembrolizumab. This early clinical observation suggests that the sequence of administration of PD‐1 blockade and chemotherapy may be important in this disease. 相似文献
105.
Shannon B. Donnola Elliott C. Dasenbrook David Weaver Lan Lu Karishma Gupta Anjali Prabhakaran Xin Yu James F. Chmiel Kimberly McBennett Michael W. Konstan Mitchell L. Drumm Chris A. Flask 《Journal of cystic fibrosis》2017,16(2):283-290
Background
Previous studies have shown that Magnetic Resonance Imaging (MRI) techniques can be used to non-invasively assess lung disease in CF patients. In this study, we compare the sensitivity of normalized T1 (nT1) and non-contrast perfusion MRI techniques to detect regional lung disease in CF patients.Materials and methods
MRI data were obtained for eight adult CF patients without overt pulmonary exacerbation (FEV1 = 45–127%) and six healthy volunteers on a Siemens Espree 1.5 T MRI scanner. Sagittal nT1 and perfusion data were acquired for each subject's left and right lungs. A region-of-interest analysis was used to calculate mean nT1 and perfusion values in the individual lobes of the left and right lungs for each subject.Results
In comparison to healthy controls, CF subjects showed a significant decrease in nT1 values in the upper lobe of the left lung as well as in the upper and anterior lobes of the right lung (p < 0.001). Similar nT1 differences were observed with in the CF cohort in comparison to their respective posterior lobes (p < 0.001). Pulmonary perfusion for the CF subjects was also significantly reduced in the upper lobe of the right lung (p < 0.05). Significant correlations with spirometry were also observed for both nT1 (left upper lobe: p < 0.01) and perfusion (left and right upper lobes (p ≤ 0.05)). Additionally, significant correlations were observed between nT1 and perfusion in the upper lobes of the left (p = 0.05) and right lungs (p = 0.005). Conclusions: This pilot study confirms that both the nT1 and non-contrast perfusion MRI techniques can sensitively detect regional lung changes in patients with CF. While both imaging methods were able to detect regional lung disease, the additional nT1 reductions in the CF patients suggests that nT1 may be more sensitive to regional CF lung disease. 相似文献106.
Benzalkonium Chloride: A Bronchoconstricting Preservative in Continuous Albuterol Nebulizer Solutions 下载免费PDF全文
For convenience, many pediatric hospitals are preparing solutions for continuous nebulized albuterol using the 0.5% 20‐ml multidose albuterol dropper bottle. This product contains benzalkonium chloride (BAC) that, by itself, produces bronchospasm that is dose dependent and cumulative. The bronchoconstrictive effects of BAC are greater in patients with more severe airway obstruction and increased airway responsiveness. Use of BAC‐containing albuterol during severe acute asthma exacerbations may antagonize the bronchodilator response to albuterol, prolong treatment, and increase the risk of albuterol‐related systemic adverse effects. Such a deleterious effect of BAC is difficult to detect because some patients improve slowly or may even worsen during treatment. We recommend that only preservative‐free albuterol products be used. 相似文献
107.
Background
Septic shock commonly leads to death in critically ill patients. Severe hypotension resistant to conventional catecholamine leads to multiorgan failure. We studied the effectiveness of low dose vasopressin in resistant septic shock.Methods
Thirty critically ill patients with catecholamine resistant hypotension were included in the study. After adequate fluid resuscitation, infusion of norepinephrine and dobutamine was started. If the patient remained hypotensive, vasopressin was infused at a fixed rate of 0.04 unit/minute for 24 hours. Haemodynamic parameters and mortality rates were recorded.Result
There was a significant improvement in systolic and mean arterial pressure within four hours of starting vasopressin. This improvement continued throughout the 24-hour period. In addition, it was possible to withdraw dopamine in all the patients and significantly reduce infusion rates of dobutamine and norepinephrine. No significant complication was noted.Conclusion
Low dose vasopressin at the rate of 0.04 unit/minute is an effective vasopressor in adult patients with catecholamine resistant septic shock.Key Words: Severe sepsis, Septic shock, Vasopressin 相似文献108.
K Prabhakaran CVR Mohan PC Tripathy PK Sahoo KI Mathai 《Medical Journal Armed Forces India》2008,64(4):308-310
Background
Craniotomy and excision of tumours can produce neurological deficits if the tumour is located close to eloquent areas of the brain. One technique of overcoming this problem is to keep the patient ‘awake’ during surgery.Methods
Eight patients with intra cranial space occupying lesions (ICSOL) were operated ‘awake’, using a combination of skull block with sedation and analgesia. A mixture of 0.125% bupivacaine and 0.5% lignocaine was used for various nerve and field blocks. Midazolam, fentanyl and propofol in titrated doses were used to achieve conscious sedation.Result
The procedure was successful in all the patients. They tolerated the procedure well and were able to follow the commands intraoperatively as desired. There were no significant complications.Conclusion
Awake craniotomy with skull blocks with sedation and analgesia is a well established procedure. It requires a good rapport between surgeon, anaesthesiologist and the patient.Key Words: Awake craniotomy, Skull block, Sedation, Analgesia 相似文献109.
Venugopal J Prabhakaran MP Low S Choon AT Zhang YZ Deepika G Ramakrishna S 《Current pharmaceutical design》2008,14(22):2184-2200
Nanotechnology is an emerging technology seeking to exploit distinct technological advances controlling the structure of materials at a reduced dimensional scale approaching individual molecules and their aggregates or supramolecular structures. The manipulation and utilization of materials at nanoscale are expected to be critical drivers of economic growth and development in this century. In recent years, nanoscale sciences and engineering have provided new avenues for engineering materials down to molecular scale precision. The resultant materials have been demonstrated to have enhanced properties and applicability; and these materials are expected to be enabling technologies in the successful development and application of nanomedicine. Nanomedicine is defined as the monitoring, repair, construction, and control of human biological systems at the molecular level using engineered nanodevices and nanostructures. Electrospinning is a simple and cost-effective technique, capable of producing continuous fibers of various materials from polymers to ceramics. The electrospinning technique is used for the preparation of nanofibers and macroporous scaffolds intended for drug delivery and tissue engineering. These have special characteristics in terms of fabrication, porosity, variable diameters, topology and mechanical properties. This review summarizes the recent developments in utilizing nanofibers for drug delivery and tissue engineering applications. 相似文献
110.