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排序方式: 共有1261条查询结果,搜索用时 46 毫秒
51.
Dr. Wieslaw J. Bochenek MD Ryszard Koronczewski MD 《Digestive diseases and sciences》1973,18(9):729-733
The effect of smoking on bicarbonate and volume of duodenal juice was studied. It was found that in the basal condition smoking produced significant decreases in bicarbonate content and volume of duodenal samples. On the contrary, during pancreatic stimulation with secretin at approximately 50% of maximal secretion, smoking resulted in significant increases in bicarbonate output and volume. Decrease in buffering power of duodenal juice in the basal condition can, at least partially, explain the causative relation of smoking and peptic ulcer disease.Supported in part by Ayerst Laboratories, New York.Boots Secretin was kindly donated by Dr. K. Cartwright of Boots Pure Drug Co. Ltd., Nottingham, England. 相似文献
52.
Paweł Śledziński Joanna Zeyland Ryszard Slomski Agnieszka Nowak-Terpiłowska 《Journal of child & adolescent substance abuse》2019,28(2):65-72
Marijuana is recently a subject of a global debate due to potential medical application of cannabis products and the progressive legalization of its recreational use. This situation leads to the need for access to comprehensive and reliable information about the effects of marijuana intake. Our review presents the actual state of knowledge regarding acute and chronic health effects generated by recreational marijuana use. Marijuana smoking can lead to structural and functional alterations in the central nervous system. These effects are especially significant and dangerous at the prenatal, child, and adolescence periods. In contrary to a common myth, cannabis does exhibit an addictive potency, albeit not a strong one. We discuss the “cannabis gateway hypothesis,” which suggests that marijuana use can be the first step before trying more dangerous drugs. However, drawing significant conclusions is difficult due to the strong impact of confounders and often unclear relationships among studied factors, especially in the socioeconomic context. Moreover, we point to the need for the unbiased assessment of the harm generated by marijuana in comparison with other drugs. 相似文献
53.
Teresa Jackowska Ryszard Konior Anna Skoczyńska Leszek Szenborn Jacek Wysocki 《Pediatria polska》2014
Authors have presented the current recommendations for the prevention of meningococcal infections. The epidemiological situation in Poland has been described and the use of currently available meningococcal vaccines has been discussed. The chemoprophylaxis for close contacts of all people with invasive meningococcal disease has been also presented. 相似文献
54.
This paper proposes and experimentally investigates a novel nondestructive testing method for ferromagnetic elements monitoring, the Magnetic Recording Method (MRM). In this method, the inspected element must be magnetized in a strictly defined manner before operation. This can be achieved using an array of permanent magnets arranged to produce a quasi-sinusoidal magnetization path. The magnetic field caused by the original residual magnetization of the element is measured and stored for future reference. After the operation or loading, the magnetic field measurement is repeated. Analysis of relative changes in the magnetic field (for selected components) allows identifying applied stress. The proposed research methodology aims to provide information on the steel structure condition unambiguously and accurately. An interpretation of the results without referring to the original magnetization is also possible but could be less accurate. The method can be used as a standard technique for NDT (Non-Destructive Testing) or in structural health monitoring (SHM) systems. 相似文献
55.
Magdalena Dudek Bartomiej Lis Ryszard Kluczowski Mariusz Krauz Magdalena Zibka Marcin Gajek Alicja Rapacz-Kmita Micha Mosiaek Piotr Dudek Dorota Majda Andrzej Ra
niak 《Materials》2022,15(7)
The development of new chemically resistant anodes for protonic ceramic fuel cells (PCFCs) is urgently required to avoid the costly deep hydrogen purification method. Ba0.95Ca0.05Ce0.9Y0.1O3−δ (5CBCY), which is more chemically resistant than BaCaCe0.9Y0.1O3−δ, was here tested as a component of a composite NiO–5CBCY anode material. A preparation slurry comprising 5CBCY, NiO, graphite, and an organic medium was tape cast, sintered and subjected to thermal treatment in 10 vol.% H2 in Ar at 700 °C. Differential thermal analysis, thermogravimetry, quadrupole mass spectrometry, X-ray diffraction analysis, scanning electron microscopy, the AC four-probe method and electrochemical impedance spectroscopy were used for the investigation. The electrical conductivity of the Ni–5CBCY in H2–Ar at 700 °C was 1.1 S/cm. In the same gas atmosphere but with an additional 5 vol.% CO2, it was slightly lower, at 0.8 S/cm. The Ni–5CBCY cermet exhibited repeatable electrical conductivity values during Ni-to-NiO oxidation cycles and NiO-to-Ni reduction in the 5CBCY matrix, making it sufficient for preliminary testing in PCFCs. 相似文献
56.
The influence of chronic stress on multiple opioid peptide systems in the rat: pronounced effects upon dynorphin in spinal cord 总被引:2,自引:0,他引:2
Ryszard Przewocki Wadysaw Laso Volker Ho
llt Jerzy Silberring Albert Herz 《Brain research》1987,413(2):213-219
Recurrent exposure to intermittent electrical foot-shock (30 min, twice daily) for 7 days caused an increase in immunoreactive (ir) dynorphin and ir-alpha-neo-endorphin in lumbar and cervical (but not thoracic) spinal cord as measured 16 h following the final session. At this time the level of ir-Met-enkephalin-Arg6-Gly7-Leu8 (MEAGL) was also increased at the lumbar level. An acute foot-shock depleted spinal cord dynorphin in chronically stressed but not in naive rats. No alterations in levels of ir-dynorphin or ir-MEAGL were seen in discrete brain tissues. In contrast to the brain, where no effects were seen, the levels of beta-endorphin increased in both lobes of the pituitary. This change, however, was not accompanied by an alteration in levels of beta-endorphin in plasma. These data show that chronic foot-shock stress selectively influences particular pools of opioid peptides, predominantly those derived from proenkephalin B in the spinal cord and from proopiomelanocortin in the anterior pituitary. It is suggested that alterations observed in the spinal cord reflect enhanced activity of the proenkephalin B system in response to chronic nociceptive stimulation. 相似文献
57.
Arkadiusz Derkacz Marcin Protasiewicz Rafa? Por?ba Adrian Doroszko Ma?gorzata Por?ba Jolanta Antonowicz-Juchniewicz Ryszard Andrzejak Andrzej Szuba 《Archives of Medical Science》2011,7(3):444-448
Introduction
Asymmetric dimethylarginine (ADMA) is an endogenous competitive inhibitor of endothelial nitric oxide synthase. Asymmetric dimethylarginine may influence the process of restenosis after coronary angioplasty. The aim of the study was to determine if initial plasma ADMA level could predict restenosis after coronary angioplasty and stenting.Material and methods
The study group consisted of 60 consecutive patients (10 women and 50 men, average age 58.9 ±10.4 years old), who underwent percutaneous coronary angioplasty with bare metal stenting for stable coronary artery disease. All patients underwent follow-up coronary angiography after a 6-month period. Patients were divided into two groups, one with restenosis (n = 22), and the other one without restenosis (n = 38). In addition to measuring acknowledged restenosis risk factors, plasma ADMA level was measured before initial angiography.Results
Asymmetric dimethylarginine plasma level was significantly higher in the group with restenosis than in the group without restenosis (1.94 ±0.94 µmol/l vs. 0.96 ±0.67 µmol/l; p < 0.05). L-arginine/ADMA ratio was also decreased in the group with restenosis, when compared with the group without restenosis (p < 0.05). Multivariate logistic regression revealed that independent restenosis risk factors were characterised by an initially high ADMA level (p < 0.01), advanced age (p < 0.05) and low level of HDL cholesterol (p < 0.05).Conclusions
Pre-procedural elevated plasma ADMA level increases the risk of restenosis in patients who underwent coronary angioplasty and stenting with bare metal stents. 相似文献58.
M Flisiński A Brymora I Bartłomiejczyk E Wiśniewska R Gołda A Stefańska L Pączek J Manitius 《Kidney & blood pressure research》2012,35(6):608-618
Background/Aims: Hypoxia-inducible factor (HIF)-1α is responsible for increased expression of genes engaged in angiogenesis. Our previous study indicated capillary rarefaction and atrophy of glycolytic fibers, mainly in locomotor muscles of uremic animals. Perhaps these changes are secondary to disturbances of HIF-1α in skeletal muscles. Methods: Expression of HIF-1α at mRNA and protein levels, as well as mRNA of vascular endothelial growth factor A (VEGF-A), vascular endothelial growth factor receptor (VEGFR)-1, VEGFR-2, endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS), in gastrocnemius muscle (MG) and longissimus thoracic muscle (ML) were measured by RT-PCR and Western blot. Rats were randomized to subtotal nephrectomy (CKD5/6), uninephrectomy (CKD1/2) or sham operation (controls). Results: For CKD5/6 versus controls, mRNA levels for HIF-1α, VEGF-A, VEGFR-1 and VEGFR-2 were significantly reduced only in MG, while eNOS was significantly decreased and iNOS was significantly increased only in ML. Western blot analysis indicated significantly increased HIF-1α protein levels in MG and ML from CKD1/2 animals versus controls, whereas in the CKD5/6 group, the level of HIF-1α protein decreased significantly in MG and increased significantly in ML versus controls and CKD1/2. Conclusion: The reduced expression of HIF-1α mRNA and protein in locomotor muscle from CKD5/6 animals may be involved in the pathogenesis of uremic myopathy. Increased expression of iNOS in the postural muscles may act as a protective factor through HIF-1α stabilization. 相似文献
59.
Irakli Giorgberidze Sanjeev Saksena Luc Mongeon Rahul Mehra Ryszard B. Krol Anand N. Munsif Philip Mathew 《Journal of interventional cardiac electrophysiology》1997,1(2):111-123
Atypical atrial flutter has, hitherto, been relatively refractory totermination by rapid atrial pacing. High-frequency pacing (HFP) in theatrium, for termination of atrial flutter or atrial fibrillation (AF), andthe electrophysiologic effects related to it have not been examined. Weexamined the clinical efficacy, safety, and electrophysiologic mechanisms ofHFP using 50-Hz bursts at 10 mA applied at the high right atrium in patientswith atypical atrial flutter (group 1) or AF (group 2), using a prospectiverandomized study protocol. Four burst durations (500, 1000, 2000, and 4000ms) were applied at the high right atrium repetitively in random sequence in22 patients with spontaneous atrial flutter or AF. Local and distant rightand left atrial electrogram recordings were analyzed during and after HFP.HFP resulted in local and distant right and left atrial electrogramacceleration in 8 of 10 patients (80%) in group 1 but caused lessfrequent local atrial electrogram acceleration (6 of 12 patients) and nodistant atrial electrogram effects in group 2 (p < .05 versus group 1).The HFP protocol was effective in arrhythmia termination in 6 of 10patients in group 1 but in no patient in group 2 (p < .05 versus group1). Standard HFP protocol applied at the high right atrium can frequentlyalter atrial activation in both atria and can terminate atypical atrialflutter. Efficacy in AF is limited, probably due to limitedelectrophysiologic actions beyond the local pacing site. 相似文献
60.
Jerzy Romaszko Ryszard Targonski Leszek Cichowski Janusz Sadowski 《Central European Journal of Medicine》2011,6(4):407-410
We report a case of an apparently well-documented indapamide-induced hyponatremia. The initial diagnosis was made on the basis of dechallenge and rechallenge performed on two occasions. Further course of the disease, which proved inconsistent with our expectations, prompted us to look for another aetiology leading to the final diagnosis of the syndrome of inappropriate antidiuretic hormone secretion (SIADH) complicated by indapamide treatment. 相似文献