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41.
42.
A single application of crude coal tar (CCT) solution (USP) to the skin of neonatal rats was shown to induce epidermal and hepatic cytochrome P-450(P-450)-dependent monooxygenase activities. To further characterize the induction response, in this study we have utilized highly specific monoclonal antibodies (MoAb) 1-7-1, 2-66-3, and 1-98-1 directed against highly purified rat liver P-450s induced by 3-methyl-cholanthrene, phenobarbital and ethanol, respectively. Sodium dodecyl sulfate polyacrylamide gel electrophoresis of hepatic microsomes prepared from CCT-treated animals showed a significant increase in the coomassie blue stainable proteins in the P-450 region; however, this was not evident in epidermal microsomes. Immunoblot analysis of epidermal and hepatic microsomes with MoAb 1-7-1 revealed strong immunoprecipitin bands in both tissues. MoAb 2-66-3 showed significant immunoreactivity only with hepatic microsomes. Interestingly, CCT treatment resulted in suppression of immunoreactivity with MoAb 1-98-1 in hepatic microsomes. MoAb 1-7-1 and 2-66-3 exhibited concentration-dependent inhibitory effects in aryl hydrocarbon hydroxylase and 7-ethoxycoumarin-O-deethylase activities induced by CCT application. MoAb 1-7-1 was substantially more effective in this respect. Epidermal and hepatic microsomes prepared from CCT-treated rats showed significantly greater metabolism of benzo(a)pyrene (BP). MoAb 1-7-1 and MoAb 2-66-3 inhibited BP metabolism in both the tissues. However, MoAb 1-7-1 was more inhibitory in this regard as compared to MoAb 2-66-3. These studies indicate that topical application of therapeutic CCT to the skin of neonatal rats results in induction of P-450 isozyme c in epidermis and isozymes b and c in liver, and that this induction is associated with the suppression of P-450 isozyme j in liver.  相似文献   
43.
OBJECTIVE: To quantify the clinical impact of methicillin-resistance in Staphylococcus aureus causing infection complicated by bacteremia in adult patients, while controlling for the severity of patients' underlying illnesses. DESIGN: Retrospective cohort study from October 1, 1995, through December 31, 2003. PATIENTS AND SETTING: A total of 438 patients with S. aureus infection complicated by bacteremia from a single Veterans Affairs healthcare system. RESULTS: We found that 193 (44%) of the 438 patients had methicillin-resistant S. aureus (MRSA) infection and 114 (26%) died of causes attributable to S. aureus infection within 90 days after the infection was identified. Patients with MRSA infection had a higher mortality risk, compared with patients with methicillin-susceptible S. aureus (MSSA) infections (relative risk, 1.7 [95% confidence interval, 1.3-2.4]; P<.01), except for patients with pneumonia (relative risk, 0.7 [95% confidence interval, 0.4-1.3]). Patients with MRSA infections were significantly older (P<.01), had more underlying diseases (P=.02), and were more likely to have severe sepsis in response to their infection (P<.01) compared with patients with MSSA bacteremia. Patients who died within 90 days after S. aureus infection was identified were significantly older (P<.01) and more likely to have severe sepsis (P<.01) and pneumonia (P=.01), compared with patients who survived. After adjusting for age as a confounder, comorbidities, and pneumonia as an effect modifier, S. aureus infection-related mortality remained significantly higher in patients with MRSA infection than in those with MSSA infection, among those without pneumonia (hazard ratio, 1.8 [95% confidence interval, 1.2-3.0]); P<.01. CONCLUSIONS: The results of this study suggest that patients with MRSA infections other than pneumonia have a higher mortality risk than patients with MSSA infections other than pneumonia, independent of the severity of patients' underlying illnesses.  相似文献   
44.
目的 对临床发生的急性输液反应进行分析,找出发生的原因,探讨预防措施。方法对201885例次输液治疗中的52例次输液反应资料进行分析。结果 经分析,属药物因素27例(52%),属操作因素11例(21%),属病人因素11例(21%),属输液器具因素3例(6%)。结论 把好药品和操作关,改善操作环境,严格操作规程是减少输液反应的关键。  相似文献   
45.
The changes in mechanical properties and free radical concentration of curing Simplex P Radiopaque Bone Cement in vivo and in vitro conditions were studied. Samples were prepared so that each in vivo sample that cured and aged in the canine femoral intramedullary cavities had an in vitro counterpart that was cured and aged in a constant-temperature saline bath at 37 degrees C. An electron paramagnetic resonance (EPR) spectrometer was used to measure the growth and decay (curing) of polymerization radicals. The results of EPR measurements showed that the curing (disappearance of free radicals) of in vivo samples takes a much longer time (more than 4 weeks) than in vitro curing (less than 2 weeks). The mechanical tests indicate that, whether aged in vivo or in vitro, the strength increased rapidly for the first 1-2 weeks and then slight increases were seen for up to 6 months.  相似文献   
46.
H Z Park  S P Lee  A L Schy 《Gastroenterology》1991,100(6):1665-1670
Ceftriaxone, a third-generation cephalosporin, is partially excreted into bile. With its clinical use, the formation of gallbladder sludge detected by ultrasonography has been reported. Four surgical specimens were examined and no gallstones were found. Instead, fine precipitates of 20-250 microns were present. Microscopically, there was a small number of cholesterol monohydrate crystals and bilirubin granules among an abundant amount of granular-crystalline material that was not morphologically cholesterol monohydrate crystals. The chemical composition of the precipitates (n = 4) was determined. There was a small amount of cholesterol (1.7% +/- 0.8%) and bilirubin (13.9% +/- 0.74%). The major component of the precipitate was a residue. On further analysis using thin-layer chromatography, high-performance liquid chromatography, and electron microprobe analysis, the residue was identified as a calcium salt of ceftriaxone. The residue also had identical crystal morphology and chromatographic elution profile as authentic calcium-ceftriaxone standards. It is concluded that ceftriaxone, after excretion and being concentrated in the gallbladder bile, can form a precipitate. The major constituent has been identified as a ceftriaxone-calcium salt.  相似文献   
47.
The objective of this study was to determine the frequency and significance of the MR findings of incomplete shell collapse for detecting implant rupture in a series of surgically removed breast prostheses. MR images of 86 breast implants in 44 patients were studied retrospectively and correlated with surgical findings at explanation. MR findings included (a) complete shell collapse (linguine sign), 21 implants; (b) incomplete shell collapse (subcapsular line sign, teardrop sign, and keyhole sign), 33 implants; (c) radial folds, 31 implants; and (d) normal, 1 implant. The subcapsular line sign was seen in 26 implants, the teardrop sign was seen in 27 implants, and the keyhole sign was seen in 23 implants. At surgery, 48 implants were found to be ruptured and 38 were intact. The MR findings of ruptured implants showed signs of incomplete collapse in 52% (n = 25), linguine sign in 44% (n = 21), and radial folds in 4% (n = 2). The linguine sign perfectly predicted implant rupture, but sensitivity was low. Findings of incomplete shell collapse improved sensitivity and negative predictive values, and the subcapsular line sign produced a significant incremental increase in predictive ability. MRI signs of incomplete shell collapse were more common than the linguine sign in ruptured implants and are significant contributors to the high sensitivity and negative predictive values of MRI for evaluating implant integrity.  相似文献   
48.
49.
Immunoscintigraphy with radiolabelled monoclonal antibodies is widely used to detect solid tumours, but only a few trials have been carried out concerning the specific in vivo localization of an inflammatory process. The purpose of this study was to investigate the detectability of tuberculous foci utilizing this method with radiolabelled bacillus Calmette-Guérin (BCG)-specific F(ab')2 in rabbits. All of the tuberculous lesions (n = 8) were clearly visualized on serial scintigraphy for up to 48 h after injection of the antibody. Immunohistochemical and Ziel-Neelson staining of the tuberculous lesions confirmed the presence of the tuberculous antigens and bacilli. It failed to demonstrate any sustained retention of the BCG-specific antibody fragment in the control group with syphilitic orchitis (n = 2). Therefore, the specific in vivo localization of tuberculosis is feasible by immunoscintigraphy.  相似文献   
50.
In previous studies, we identified a 55 kD organic anion-binding protein in liver cell sinusoidal plasma membrane subfractions. Other investigators identified another 55 kD bromosulfophthalein/bilirubin binding protein on the surface of rat hepatocytes and HepG2 cells and suggested that this protein served as a transporter for these ligands. In this study, transport of 35S-sulfobromophthalein by the human hepatoma cell line, HepG2, was quantified in the presence and absence of bovine serum albumin to further clarify the possible function of these plasma membrane binding proteins. In contrast to results in normal rat hepatocytes, virtually no uptake of 35S-sulfobromophthalein by HepG2 cells in the presence of bovine serum albumin was found. In the absence of albumin, HepG2 cells expressed temperature-dependent uptake of 35S-sulfobromophthalein. However, the high-affinity Cl(-)-dependent sulfobromophthalein transport that characterizes normal rat hepatocytes was absent, as indicated by an approximately 95-fold lower affinity and 170-fold higher capacity of HepG2 cells for sulfobromophthalein compared with previous results with rat hepatocytes. These results suggest that 55 kD sulfobromophthalein/bilirubin-binding protein on the liver cell surface differs from organic anion-binding protein and is not responsible for sulfobromophthalein extraction in the presence of albumin, although it may play some role in lower affinity transport by cells. Immunoblot analysis and metabolic labeling of HepG2 cells demonstrated synthesis of organic anion-binding protein. However, light microscopic immunocytochemistry and immunoprecipitation of surface iodinated rat hepatocytes and HepG2 cells with antibody to a recombinant organic anion-binding protein fusion protein indicated absence of organic anion-binding protein on the surface of HepG2 cells.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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