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排序方式: 共有531条查询结果,搜索用时 15 毫秒
1.
Bradley J Catalone Shendra R Miller Mary Lee Ferguson Dan Malamud Tina Kish-Catalone Nina J Thakkar Fred C Krebs Mary K Howett Brian Wigdahl 《Biomedicine & Pharmacotherapy》2005,59(8):430-437
C31G, which has potent activity against the human immunodeficiency virus type 1 (HIV-1) and an established record of safety in animal studies and human trials, is a microbicidal agent comprised of a buffered equimolar mixture of two amphoteric, surface-active agents: an alkyl amine oxide (C14AO) and an alkyl betaine (C16B). Studies of long-term in vitro exposure to C31G and its constituents have suggested that the components of C31G may contribute differentially to its toxicity and efficacy. In the present studies, in vitro assays of cytotoxicity and anti-HIV-1 activity demonstrated that C16B was slightly less cytotoxic compared to either C31G or C14AO, whereas the anti-HIV-1 activities of C31G and its individual constituents were similar. In the murine model of cervicovaginal microbicide toxicity, in vivo exposure to C14AO resulted in severe cervical inflammation followed by a delayed disruption of the columnar epithelium. In contrast, exposure to C16B caused severe cervical epithelial disruption and a secondary, less intense inflammatory response. These results demonstrate that (i) there are both mechanistic and temporal differences in toxicity associated with the components of C31G not necessarily predicted by in vitro assessments of cytotoxicity and (ii) contributions of each component to the anti-HIV-1 activity of C31G appear to be equal. In addition, these findings indicate that direct and indirect mechanisms of in vivo toxicity can be observed as separate but interrelated events. These results provide further insight into the activity of C31G, as well as mechanisms potentially associated with microbicide toxicity. 相似文献
2.
A case of multiple myeloma diagnosed by fine-needle aspiration (FNA) biopsy and confirmed by laboratory studies in a patient with a history of renal-cell carcinoma is presented. The patient was diagnosed with renal-cell carcinoma of the right kidney and a radical nephrectomy was performed. Eighteen months after this diagnosis was made, the patient developed chest wall pain and was found to have osteolytic bone lesions of the ribs and vertebral bodies. FNA of an osteolytic rib lesion disclosed multiple myeloma. Additional laboratory studies confirmed the diagnosis of multiple myeloma. This case report demonstrates the value of FNA as a diagnostic tool for the follow-up of cancer patients, the subsequent discrimination between metatastic lesions and a second primary malignancy, and the cytology of multiple myeloma. 相似文献
3.
Summary Fenfluramine, an amphophilic compound which is a halogenated derivative of amphetamine, is still used as an anorectic agent for weight reduction, as it acts on the satiety center of the hypothalamus. Holtzman strain rats aged 6 days were daily injected s.c. fenfluramine hydrochloride at the dose of 75 mg/kg body weight. The animals were killed at different time intervals between days 7 and 40, and different parts of the brain were examined by light and electron microscopy. About half of the animals showed intralysosomal membrano-cytoplasmic bodies in the oligodendroglia, neurons, and neuropil, maximally in the animals receiving 8–19 injections. They were seen as concentrically arranged, single-layered lamellae; small dense bodies; or larger heterogeneous bodies. The mechanism of production of such inclusions could be the formation of complexes of this amphophilic compound with tissue phospholipids, or some enzyme-inhibiting action. A marked prominence of dark cells, predominantly oligodendroglia, was also noticed in the brains of experimental animals. Some of these cells appeared to be dark neurons, probably resulting from the serotonin-depleting effect of fenfluramine. A few dark cells were identified as resting microglial cells, while macrophagic reactive microglia were detected in the brains of very young animals. Fenfluramine appears to provide a model for studying neuroglial reactions.Paper presented at the Erwin Riesch symposium on Lysosomal Disorders of the Nervous System, Berlin (Convenor, Prof. Cervos-Navarro); and as poster-talk at the 9th International Congress of Neuropathology, Vienna, September 1982 相似文献
4.
Courtney Pisano Renata Fabia Junxin Shi Krista Wheeler Sheila Giles Lisa Puett Dylan Stewart Susan Ziegfeld Jennifer Flint Jenna Miller Pablo Aguayo Emily C. Alberto Randall S. Burd Lisa Vitale Justin Klein Rajan K. Thakkar 《Burns : journal of the International Society for Burn Injuries》2021,47(3):545-550
BackgroundAccurate resuscitation of pediatric patients with large thermal injury is critical to achieving optimal outcomes. The goal of this project was to describe the degree of variability in resuscitation guidelines among pediatric burn centers and the impact on fluid estimates.MethodsFive pediatric burn centers in the Pediatric Injury Quality Improvement Collaborative (PIQIC) contributed data from patients with ≥15% total body surface area (TBSA) burns treated from 2014 to 2018. Each center's resuscitation guidelines and guidelines from the American Burn Association were used to calculate estimated 24-h fluid requirements and compare these values to the actual fluid received.ResultsDifferences in the TBSA burn at which fluid resuscitation was initiated, coefficients related to the Parkland formula, criteria to initiate dextrose containing fluids, and urine output goals were observed. Three of the five centers’ resuscitation guidelines produced statistically significant lower mean fluid estimates when compared with the actual mean fluid received for all patients across centers (4.53 versus 6.35 ml/kg/% TBSA, p < 0.001), (4.90 versus 6.35 ml/kg/TBSA, p = 0.002) and (3.38 versus 6.35 ml/kg/TBSA, p < 0.0001).ConclusionsThis variation in practice patterns led to statistically significant differences in fluid estimates. One center chose to modify its resuscitation guidelines at the conclusion of this study. 相似文献
5.
Measurement of albumin and low molecular weight proteins in the urine of newborn infants using a cotton wool ball collection method 总被引:2,自引:0,他引:2
Objective : The aim of this study was to investigate the inter-relationship between urinary excretion of alpha-1-microglobulin (AIM), retinol-binding protein (RBP) and albumin in term and premature neonates, with urine collected into cotton wool balls and extracted by a novel method. Subjects and methods : Sixty-four infants were studied on the first day of life; 26 had been born at term (37–42 weeks gestation) and 38 prematurely (24–28 weeks n = 16, 29–36 weeks n = 22). Urine collected into cotton wool balls was analysed following a new detergent extraction method, which resulted in a recovery rate of 94–107% for albumin, AIM, RBP and creatinine. Results : Urinary protein excretion, expressed as a ratio to urinary creatinine, decreased significantly with increasing gestational age (24–28 weeks, 29–36 weeks, 37–42 weeks: albuminxreatinine ratio mg/mmol mean 96.9, 31.7, 19.3; AIM: creatinine ratio mg/mmol mean 99.3, 37.0, 7.8; RBP: creatinine ratio mg/mmol mean 16.2, 3.8, and <0.01, below the limit of detection, respectively). When results were corrected for birthweight, this gestation-associated effect was still present for A1M and RBP, but not for albumin. In premature infants there was a significant positive correlation between AIM: creatinine ratio and RBP: creatinine ratio ( r = 0.85), and also between albumin and both AIM and RBP ( r = 0.82 and 0.77). Conclusion : Increased excretion of AIM, RBP and albumin at earlier gestational ages is probably due to proximal tubular immaturity, although tubular damage and also glomerular dysfunction cannot be excluded as possible explanations. 相似文献
6.
Melani W. Setiawan Tatang K. Samsi Hansa Wulur Djoharman Sugianto Thomas N. Pool 《Pediatric radiology》1998,28(1):1-4
In a prospective study, the relationship between the clinical severity of dengue haemorrhagic fever (DHF) and the sonographic
findings was examined. The study comprised 73 cases classified as mild (grades I–II) and 75 as severe (grades III–IV). Ultrasonography
in the mild group revealed pleural effusions in 30 %, ascites in 34 %, gallbladder wall thickening in 32 %, hepatomegaly in
49 %, splenomegaly in 16 %, and pancreatic enlargement in 14 %. In the severe group, pleural effusions, ascites and gallbladder
wall thickening were found in 95 %, pararenal and perirenal fluid collections in 77 %, hepatic and splenic subcapsular fluid
collections in 9 %, pericardial effusion in 8 %, hepatomegaly in 56 %, splenomegaly in 16 %, and pancreatic gland enlargement
in 44 %. Ultrasound may be useful for early prediction of the severity of DHF in children.
Received: 15 January 1997 Accepted: 2 June 1997 相似文献
7.
Raja-Jones H 《Journal of clinical nursing》2002,11(4):415-420
This paper focuses on issues relating to the role components of clinical nurse specialists and clinical research nurses working in breast cancer care. Identified issues relate to the lack of agreement as to the role and definition of clinical nurse specialists. At the same time there has been an increase and emergence of clinical research nurses, both within the NHS and university departments. The review fails to reveal the relationship between these two specialist groups in terms of role overlap and role boundaries. The lack of knowledge in this area substantiates the need for further research to be carried out. 相似文献
8.
In this study, the syntheses of a BaCuO3 perovskite-structured oxide and rGO were conducted using a sol–gel method and ultrasonication process, respectively. Their physico-chemical characteristics were studied by powder X-ray diffraction (PXRD), Raman spectroscopy, and ultraviolet-visible (UV-vis) spectroscopy analyses. The perovskite type particles were found to present as a cubic crystal system with a crystal size in the range of 10–60 nm. Their catalytic performance was investigated using differential thermal analysis (DTA) measurements at varying heating rates via the thermal decomposition of ammonium perchlorate (AP) and 3-nitro-1,2,4-triazol-5-one (NTO). The kinetics and thermodynamics parameters, such as the average activation energy, pre-exponential factor, entropy, and Gibbs free energy, were also investigated, which showed a decrease in the decomposition peak temperature of AP and NTO in the presence of the catalysts rGO, BaCuO3, and rGO + BaCuO3 compared to pure AP and NTO.The thermal decomposition of AP and NTO was investigated in the presence of rGO, a perovskite structured BaCuO3 catalyst, and composite rGO + BaCuO3 using DTA analysis. These catalysts highly decreased the decomposition peak temperature of AP and NTO compared to pure AP and NTO. 相似文献
9.
The goal of palliative care is the achievement of the best quality of life for patients and their families. Eyes are generally the first features of the face to be noticed. Loss of an eye is a traumatic event which has a crippling effect on the psychology of the patient. Several ocular and orbital disorders require surgical intervention that may result in ocular defects. An ocular prosthesis is fabricated to restore the structure, function, and cosmetics of the defects created by such conditions. Although an implant eye prosthesis has a superior outcome, due to economic factors it may not be a feasible option for all patients. Therefore, a custom-made ocular prosthesis is a good alternative. This case report presents a palliative treatment for a patient with an enucleated eye by fabricating a custom ocular prosthesis which improved his psychological, physical, social, functional, emotional and spiritual needs. 相似文献
10.
Raymond F. Hamilton Zheqiong Wu Megha Thakkar Somenath Mitra 《Inhalation toxicology》2013,25(11-12):429-438
AbstractObjective: The toxicity of silver nanomaterials in various forms has been extensively evaluated, but the toxicity of silver nanocarbon composites is less well understood. Therefore, silver-carbon nanotube composites (Ag-MWCNT-COOH) and silver-graphene oxide composites (Ag-GO) were synthesized by microwave irradiation and evaluated in two in vitro cell models.Materials/Methods: Toxicity of silver nanosphere (Ag), Ag-MWCNT-COOH and Ag-GO were analyzed by MTS assay and LDH assay in primary C57BL/6 murine alveolar macrophages and human THP-1 cells. Activation of NLRP3 inflammasome by particle variants in these models was done by proxy using LPS co-culture and IL-1β release.Results: The results depended on the model, as the amount of Ag on the modified carbon resulted in slightly increased toxicity for the murine cells, but did not appear to affect toxicity in the human cell model. IL-1β release from carbon particle-exposures was decreased by the presence of Ag in both cell models. Suspensions of Ag-MWCNT-COOH, Ag-GO and Ag in artificial lysosomal fluid were prepared and ICP-MS was used to detect Ag ions concentration in three silver suspension/solutions. The amount of Ag ions released from Ag-MWCNT-COOH and Ag-GO were similar, which were both lower than that of Ag nanospheres.Conclusions: The results suggest the bioactivity of silver composites may be related to the amount of Ag ions released, which can be dependent on the cell model under investigation. 相似文献