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41.
Quinine overdose: review of toxicity and treatment   总被引:1,自引:0,他引:1  
Quinine sulfate is a commonly prescribed remedy for idiopathic nocturnal leg cramps and is now available "over the counter." A 24-year-old man ingested 8 g (a commonly dispensed quantity) of quinine sulfate in a suicide attempt. Despite hemoperfusion begun 10 h after ingestion, the patient died. This report reviews the toxic manifestations of quinine and the currently available modes of treatment.  相似文献   
42.
目的 观察硫酸镁雾化吸入辅助治疗对重症毛细支气管炎患儿气道阻力、肺功能及炎症因子的影响。方法 选择于医院治疗的重症毛细支气管炎患儿88例,以随机数字表法分组,44例患儿为探究组,采用硫酸镁雾化吸入辅助常规治疗,44例患儿为参照组,采用常规治疗,两组患儿均连续治疗7 d,治疗前、后检测两组患儿炎症指标:肿瘤坏死因子α(tumor necrosis factor-α,TNF-α)、可溶性血管细胞黏附分子1(soluble vasccular cell adhesion molecule-1,sVCAM-1)、Nod样受体蛋白3(Nod-like receptor pyrin domain3,NLRP3)、嗜酸粒细胞阳离子蛋白(eosinophil cationic protein, ECP)水平:气道阻力指标:近端气道黏性阻力(R20)、气道总阻抗(Z5)、气道总黏性阻力(R5)、肺神经源性P物质水平;肺功能指标:有效呼吸道阻力(Reff)、第1秒用力呼气容积(forced expiratory volume in one second, FEV1)、最大呼气中段流量(maximal mi...  相似文献   
43.
A study aimed at investigating the behavioural effects of aztreonam and gentamicin, given separately or in combination, was carried out in mice. Animals were randomly assigned to two test conditions: acute and chronic treatment. Those receiving acute treatment had a single IP injection 60 min before the test. Those receiving chronic treatment had IP injections once daily for 5 successive days prior to the test. Behavioural patterns (ambulation, rearing, grooming and defecation) were assessed using the "open-field" test. The results indicate that, both after single and multiple dosing, aztreonam (10, 40 and 80 mg/kg IP) and/or gentamicin (10 mg/kg IP) do produce changes in the behaviour of animals. A rate increasing effect for certain behaviours (rearing, grooming and defecation) and a reduction in other behaviours (ambulation) seems to occur.  相似文献   
44.
Drug interactions between the aminoglycosides (tobramycin and gentamicin) and atracurium and vecuronium were studied prospectively in 44 patients. Twenty-two patients had therapeutic serum levels of tobramycin or gentamicin and 22 served as controls. Onset time, clinical duration, and time to spontaneous recovery of T4/T1 ratio of 0.70 after atracurium or vecuronium injection were measured. No statistically significant differences were found in onset time, but clinical duration and time to recovery were significantly longer in patients receiving tobramycin or gentamicin and paralyzed with vecuronium than for controls (P less than 0.01 for clinical duration and P less than 0.0005 for recovery). The neuromuscular block produced by atracurium was not significantly influenced by the presence of therapeutic serum levels of tobramycin or gentamicin. We conclude that for patients treated with these antibiotics, atracurium may present some advantages over vecuronium when a prolonged block is not desired.  相似文献   
45.
Interactions between rabbit-γ-immunoglobulins and model membranes (lipid monalayers, planar lipid bilayers, liposomes) have been investigated. No significant interaction was observed with immunoglobulins. However, immunoglobulins dialysed first vs aqueous buffer having pH 2 or 3 and then dialysed against pH 7 buffer presumably adopt a new conformation which allows their bindings to model membranes. This binding is hydrophobic and the immunoglobulin region interacting with the lipid acyl chains is probably located in the heavy chain, as suggested by labelling in this region by a photosensitive probe previously incorporated into the lipid hydrophobic core. Cleavage at the hinge region by papain or pepsin, or heating above 38°C, induces the loss of the hydrophobic conformation responsible for hydrophobic bindings. The binding capacity of immunoglobulins heated above 38°C is restored after momentary dialysis at pH 2. The possible existence of two Ig isomers is discussed in relation to the mechanism of γ-immunoglobulin passage through the endoplasmic membrane and fixation into the plasma membrane.  相似文献   
46.
The presence of histidine-rich protein (HRP) related genes and gene products in Plasmodium falciparum was demonstrated using a synthetic pentahistidine-encoding oligonucleotide and a cloned HRP cDNA probe prepared from the avian parasite P. lophurae. In Northern blotting experiments, two knobby clones of P. falciparum were found to contain a 3500 nucleotide RNA species that hybridized with the oligonucleotide and HRP cDNA probes. As this component had the expected size for an mRNA encoding an 80-90 kDa protein and was absent from two knobless clones of P. falciparum, we concluded that it represented a 'knob protein' mRNA. Using the restriction enzyme EcoRI, three identical cross-hydribizing HRP gene fragments were found in the DNA of both knobby and knobless clones of P. falciparum. These fragments differed in size from those present in P. lophurae. These results suggest that the absence of knob protein mRNA in knobless clones is not due to loss of the corresponding gene(s).  相似文献   
47.
Keratan sulfate proteoglycan and dermatan sulfate proteoglycan have been reported to inhibit collagen fibrillogenesis. We investigated their distribution in order to evaluate the role of proteoglycan in dentinogenesis. Specimens of porcine tooth-germ dentin and erupted teeth were the materials on which antibodies to keratin sulfate and dermatan sulfate proteoglycan were used. Predentin was found to be positive for both antibodies and the reaction ceased in the calcification front. Uniformly thick collagen fibrils (30-70 nm in diameter) were distributed in the predentin matrix, which would become intertubular dentin in the future. Both antibodies reacted positively along these fibrils. In contrast, along the surface layer of dentin in the tooth germ and that in erupted teeth, collagen fibrils of 10-300 nm in diameter were noted occasionally in dentinal tubules whose odontoblastic processes had disappeared and these heterogeneous fibrils were negative for both antibodies. Our findings suggest that keratan sulfate proteoglycan and dermatan sulfate proteoglycan distributed in the predentin inhibit calcification of collagen fibrils in the uncalcified matrix and disappear in the calcification front. It is further suggested that keratan sulfate proteoglycan and dermatan sulfate proteoglycan distributed along collagen fibrils in the predentin matrix maintain uniform thickness, whereas collagen fibrils in dentinal tubules varied in thickness because of the absence of involvement of both proteoglycans. Therefore, keratan sulfate proteoglycan and dermatan sulfate proteoglycan were thought to be involved in both calcification and matrix formation.  相似文献   
48.
Chondroitin sulfate dipalmitoylphosphatidylethanolamine (CS-PE), when immobilized onto substratum, inhibited the adhesion of B16F10 mouse melanoma cells to fibronectin-coated dishes (anti-adhesion activity). CS-PE showed the most potent anti-adhesion activity for the melanoma cells among various GAG-PEs. CS-PE also inhibited the adhesion of B16F10 cells to Matrigel and the invasion of the cells into Matrigel. In the in vivo system of experimental metastasis, administration of B16F10 cells with CS-PE into C57BL/6 mice significantly inhibited lung metastasis. The inhibition degree of CS or hyaluronic acid-PE was lower than CS-PE. CS-PE administered intravenously into mice before the injection of B16F10 cells also inhibited metastasis. Pretreatment of B16F10 cells with CS-PE caused some but a lower degree of inhibition. When CS-PE was injected intravenously into mice, more binding in the lung was found than when CS was injected. CS-PE but not CS inhibited the retention in the lung of fluorochrome-labeled B16F10 cells when injected intravenously into mice. Since there was no significant effect of CS-PE on the viability and growth of B16F10 cells, the results suggest that CS-PE immobilized onto the subendothelial matrix may prevent melanoma cells from adhering to the subendothelial substrata of lung capillaries and inhibit subsequent invasion processes of metastasis.  相似文献   
49.
The production and serologic, as well as immunochemical properties of a cytotoxic murine IgG monoclonal antibody (Tü109) that precipitates HLA-class I molecules, are described. In the microcytotoxicity assay Tü109 supernatant was demonstrated on a panel of 424 HLA-ABC, -DR, -DQ, -MT typed normal Caucasian blood donors to define an epitope on HLA-B locus molecules in great association with the supertypic specificity Bw4. Reactivity of supernatant showed MHC linked inheritance of the Tü109 determinant and discriminated the HLA-Bw4/Bw6 associated HLA-B locus split antigens. Weak or lack of binding on lymphocytes from some HLA-Bw4 heterozygous individuals, particularly typing for HLA-Bw44, appeared to be due to qualitative and/or quantitative variations of HLA-B locus molecules on the cell surface. With Tü109 ascites fluid, however, extra-reactivity on all HLA-Bw6+ cells was demonstrated. Preferential binding of supernatant to HLA-Bw4, but reactivity of ascites fluid with HLA-Bw6+ molecules in addition, was furthermore confirmed by IEF analysis of antigens immunoprecipitated with Tü109 from cell lysates. Thus the antibody may help to analyze the evolutionary relationship of the diallelic specificities Bw4 and Bw6.  相似文献   
50.
In total, 120 Escherichia coli isolates positive for one of the gentamicin resistance (GEN(R)) genes aac(3)-II, aac(3)-IV or ant(2')-I were tested for gentamicin susceptibility by the agar dilution method. Isolates positive for aac(3)-IV or ant(2')-I had an MIC distribution of 8-64 mg/L, whereas isolates positive for aac(3)-II had MICs of 32 to >512 mg/L, suggesting a relationship between the distribution of MICs and the specific GEN(R) mechanism. The MIC distribution, regardless of the GEN(R) mechanism, was 8 - >512 mg/L, which supports the clinical breakpoint of MIC >4 mg/L suggested by EUCAST and questions the breakpoint recommended by the CLSI (> or =16 mg/L).  相似文献   
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