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101.
Acute cardiac events temporally related to cocaine abuse 总被引:17,自引:0,他引:17
J M Isner N A Estes P D Thompson M R Costanzo-Nordin R Subramanian G Miller G Katsas K Sweeney W Q Sturner 《The New England journal of medicine》1986,315(23):1438-1443
The increasingly widespread use of cocaine in the United States has been accompanied and perhaps exacerbated by the misconception that the drug is not associated with serious medical complications. In particular, the potential for cocaine to precipitate life-threatening cardiac events needs to be reemphasized. We report the clinical and pathological findings in seven people in whom nonintravenous "recreational" use of cocaine was temporally related to acute myocardial infarction, ventricular tachycardia and fibrillation, myocarditis, sudden death, or a combination of these events. We also review data on 19 previously reported cases of cocaine-related cardiovascular disorders. Analysis of all 26 patients indicated the following findings: the cardiac consequences of cocaine abuse are not unique to parenteral use of the drug, since nearly all the patients took the drug intranasally; underlying heart disease is not a prerequisite for cocaine-related cardiac disorders; seizure activity, a well-documented noncardiac complication of cocaine abuse, is neither a prerequisite for, nor an accompanying feature of, cardiac toxicity of cocaine; and the cardiac consequences of cocaine are not limited to massive doses of the drug. Although the pathogenesis of cardiac toxicity of cocaine remains incompletely defined, available circumstantial evidence suggests that cocaine has medical consequences that are equal in importance to its well-documented psychosocial consequences. 相似文献
102.
Pethannan Subramanian Krishnan Venkatarao 《Macromolecular chemistry and physics.》1983,184(12):2447-2455
New aromatic polyamides containing azomethine groups in the backbone and also having different linking groups like ? CH2? , ? CH2? CH2? , and ? O? were synthesized by reacting 4,4′-[1,4-phenylenebis(methylidynenitrilo)]dibenzoyl dichloride (2) with some diamines 1a – d, 4, and 6 by the low temperature solution polycondensation method. The physical, spectral, and thermal properties of the synthesized polyamides were investigated. The effect of the nature of different linking groups on the properties of these aromatic polymides was explored by comparing their spectral and thermal data. 相似文献
103.
104.
Sabina Rak MD PhD Anette Bjrnson MSc Lena Hkanson MSc PhD Sverre Srenson MD PhD Per Venge MD PhD 《The Journal of allergy and clinical immunology》1991,88(6):878-888
Two groups of birch pollen--allergic patients with seasonal rhinoconjunctivitis and asthma were followed during two consecutive birch-pollen seasons, one group, N = 10, during a season with high pollen load, and one group, N = 15, during a season of low pollen load. Half the patients were treated with immunotherapy (IT) for 3 and 4 years, respectively. The other half of the patients served as control group (non-IT). Bronchoalveolar lavage (BAL) was performed once before each season and once during the pollen season. Eosinophil (EOS) numbers in BAL were increased (p less than 0.01) during the season with high pollen load but not in the season with a low pollen load, and this increment was absent in the IT-treated group. Also, the EOS cationic protein levels were raised in the non-IT-treated group during the season with a high pollen load. The levels of EOS and neutrophil chemotactic activity were raised in BAL in both seasons in the non-IT-treated group compared with the IT-treated group (p less than 0.02, p less than 0.003, p less than 0.04, and p less than 0.005 in high- and low-load pollen season, respectively). Serum and BAL eosinophil chemotactic activity (ECA) were positively correlated (p less than 0.001). We conclude that there is an influx of active EOSs into the lung of pollen-allergic patients with asthma during a pollen season, which may be abrogated by IT. Furthermore, the generation of ECA appears to be an extremely sensitive marker of antigenic exposure, and the potent inhibition of the generation of ECA by IT may provide a clue as to the mechanism of this treatment. 相似文献
105.
Crosslinked chitosan: its physical properties and the effects of matrix stiffness on chondrocyte cell morphology and proliferation 总被引:2,自引:0,他引:2
Chitosan [beta(1-4)-2 amino-2-deoxy-D-glucose], the natural polyaminosaccharide derived from N-deacetylation of chitin [beta(1-4)-2 acetamide-2-deoxy-D-glucose], has been shown to possess attractive biological and cell interactive properties. Recently chitosan and chitosan analogs have also been shown to support the growth and continued function of chondrocytes. In the present study, chitosan substrates are crosslinked with a functional diepoxide (1,4 butanediol diglycidyl ether) to alter its mechanical property, and the viability and proliferation of the canine articular chondrocytes seeded on the crosslinked surface are further assayed. Of interest is the impact of substrate stiffness on the growth and proliferation of articular canine chondrocytes. Crosslinked scaffolds were also subjected to degradation by chitosanase to examine the impact of crosslinking on enzyme-assisted degradation. The hydrophilicity and compression modulus of the crosslinked surfaces were measured via contact-angle measurements and compression tests, respectively. Scanning electron microscopy (SEM) and fluorescent staining were used to observe the proliferation and morphology of chondrocyte cells on noncrosslinked and crosslinked surfaces. The crosslinked chitosan was found to be nontoxic to chondrocytes and more hydrophilic. Its compression modulus and stiffness increased, which may improve the scaffold resistance to wear and in vivo shrinkage once implanted. The increased stiffness also seemed to serve as an additional mechanical stimulus to promote chondrocyte growth and proliferation. The cell morphology on crosslinked scaffolds seen by SEM and fluorescent stain was the typical chondrocytic rounded shape. The method proposed provides a nontoxic way to increase the mechanical strength of the chitosan scaffolds. 相似文献
106.
Kris Deering DipHe RMN BSc MH Inpatient Care MSc P.G. Ed PhD student. Jo Williams BSc RMN MSc PhD. Kay Stayner BSc RMN. Chris Pawson BSc PGCHE PhD. 《Nursing philosophy》2021,22(1):e12329
As a philosophical position, pragmatism can be critiqued to distinguish truth only with methods that bring about desired results, predominantly with scientific enquiry. The article hopes to dismiss this oversimplification and propose that within mental health nursing, enquiry enlightened by pragmatism can be anchored to methods helping to tackle genuine human problems. Whilst pragmatists suggest one reality exists, fluctuating experiences and shifting beliefs about the world can inhabit within; hence, pragmatists propose reality has the potential to change. Moreover, pragmatism includes being cognisant of what works to whom reality concerns, making reality context-driven, with a view to understand how actions shape experiences so what is generated has usefulness. Hence, it somewhat follows pragmatism can inform mental health nursing, after all, nursing is a discipline of action, and awareness is needed in how actions produce experiences that patients find helpful. Given the principles of recovery are preferably adopted in mental health care, the paper will explore how pragmatism can help nurses move towards that goal; specifically, with patients voicing their experiences. This is because like pragmatism, recovery subscribes to hope that reality can progress, and through meaningful experiences and beliefs, patients have expertise about personal difficulties alongside how life may flourish, despite mental illness. 相似文献
107.
108.
Gerson M. Struik MSc MD PhD Bram Schermers MSc Ingeborg Mares MSc MD PhD Harold E. Lont MSc MD Jennifer W. Bradshaw MSc MD Bernard ten Haken MSc Ir PhD Theo J. M. Ruers MSc MD PhD Jurgen E. M. Mourik PhD Erwin Birnie MSc PhD Taco M. A. L. Klem MSc MD PhD 《The breast journal》2021,27(8):638-650
Wire-guided localization (WGL) is the standard of care in the surgical treatment of nonpalpable breast tumors. In this study, we compare the use of a new magnetic marker localization (MaMaLoc) technique to WGL in the treatment of early-stage breast cancer patients. Open-label, single-center, randomized controlled trial comparing MaMaLoc (intervention) to WGL (control) in women with early-stage breast cancer. Primary outcome was surgical usability measured using the System Usability Scale (SUS, 0–100 score). Secondary outcomes were patient reported, clinical, and pathological outcomes such as retrieval rate, operative time, resected specimen weight, margin status, and reoperation rate. Thirty-two patients were analyzed in the MaMaLoc group and 35 in the WGL group. Patient and tumor characteristics were comparable between groups. No in situ complications occurred. Retrieval rate was 100% in both groups. Surgical usability was higher for MaMaLoc: 70.2 ± 8.9 vs. 58.1 ± 9.1, p < 0.001. Patients reported higher overall satisfaction with MaMaLoc (median score 5/5) versus WGL (score 4/5), p < 0.001. The use of magnetic marker localization (MaMaLoc) for early-stage breast cancer is effective and has higher surgical usability than standard WGL. 相似文献
109.
110.
Robin K. Avery Jennifer D. Motter Kyle R. Jackson Robert A. Montgomery Allan B. Massie Edward S. Kraus Kieren A. Marr Bonnie E. Lonze Nada Alachkar Mary J. Holechek Darin Ostrander Niraj Desai Madeleine M. Waldram Shmuel Shoham Seema Mehta Steinke Aruna Subramanian Janet M. Hiller Julie Langlee Sheila Young Dorry L. Segev Jacqueline M. Garonzik Wang 《American journal of transplantation》2021,21(4):1564-1575
Desensitization has enabled incompatible living donor kidney transplantation (ILDKT) across HLA/ABO barriers, but added immunomodulation might put patients at increased risk of infections. We studied 475 recipients from our center from 2010 to 2015, categorized by desensitization intensity: none/compatible (n = 260), low (0-4 plasmaphereses, n = 47), moderate (5-9, n = 74), and high (≥10, n = 94). The 1-year cumulative incidence of infection was 50.1%, 49.8%, 66.0%, and 73.5% for recipients who received none, low, moderate, and high-intensity desensitization (P < .001). The most common infections were UTI (33.5% of ILDKT vs. 21.5% compatible), opportunistic (21.9% vs. 10.8%), and bloodstream (19.1% vs. 5.4%) (P < .001). In weighted models, a trend toward increased risk was seen in low (wIRR = 0.771.402.56,P = .3) and moderately (wIRR = 0.881.352.06,P = .2) desensitized recipients, with a statistically significant 2.22-fold (wIRR = 1.332.223.72,P = .002) increased risk in highly desensitized recipients. Recipients with ≥4 infections were at higher risk of prolonged hospitalization (wIRR = 2.623.574.88, P < .001) and death-censored graft loss (wHR = 1.154.0113.95,P = .03). Post–KT infections are more common in desensitized ILDKT recipients. A subset of highly desensitized patients is at ultra-high risk for infections. Strategies should be designed to protect patients from the morbidity of recurrent infections, and to extend the survival benefit of ILDKT across the spectrum of recipients. 相似文献