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91.
Pulmonary granuloma is a common lesion for which gram-negative bacteria are rarely implicated as a cause. Hence, most physicians are unaware of this etiology. We isolated a gram-negative bacterium from a surgically resected pulmonary granuloma in a 42-year-old, nonimmunocompromised woman. Within the necrotizing granuloma, numerous organisms also were demonstrated by Gram stain, suggesting a cause-disease relationship. Characterization of the bacterium by sequence analysis of the 16S ribosomal gene, cellular fatty acid profiling, and microbiologic studies revealed a novel bacterium with a close relationship to Pseudomonas. We propose a new species for the bacterium, Pseudomonas andersonii. These results suggest that the differential diagnosis of a lung granuloma also should include this gram-negative bacterium as a potential causative agent, in addition to the more common infections caused by acid-fast bacilli and fungi. This bacterium was shown to be susceptible to most antibiotics that are active against gram-negative bacteria.  相似文献   
92.
本文报告了应用三种不同类型杀虫剂DDVP,残杀成和溴江菊酯点滴处理敏感株德国小蠊(Blattellagermanica)不同虫期后的药物敏感性以及带荚虫脱荚及其孵化情况。试验得出了不同虫期不同时间的LD50植和72h不同虫期对这3种药物敏感性的显著性测定(P值)的结果。发现不同虫期对这3种药物的敏感性之间关系的共同特点是:1.幼虫与雄虫敏感性差别显著(在DDVP和残杀威中)或者非常显著(在溴氰菊酯);2.雌虫与雄虫间差别在3种药物处理中均显著;3.雌虫与带荚虫在DDVP和溴氰菊酯处理中差别也非常显著。试验同时显示,3种药物不同浓度处理对德国小蠊脱荚及其孵化有十分显著的影响。其总的趋势是随着药物浓度的增高脱荚率明显地增加;相反,脱荚的孵化率则随着浓度的增加明显的下降。实验并得出脱荚的孵化与否和卵荚长度无明显关系。  相似文献   
93.
To facilitate study of alveolar macrophages in vivo, we developed a method to rapidly and efficiently replace resident alveolar macrophages with macrophages of a different (donor) genotype. Chimeric mice were generated by lethal irradiation followed by fetal liver transplantation (FLT) using green fluorescent protein (GFP) transgenic reporter mice as donors. Kinetics of peripheral blood monocyte (PBM) and alveolar macrophage reconstitution was determined 4 and 10 weeks post-FLT by quantifying the percentage of GFP+ cells. To enhance the recruitment of donor monocytes into the lung after FLT, mice were treated with intratracheal administration of liposomal clodronate to deplete host alveolar macrophages at 6 weeks post-FLT. PBM reconstitution occurred by 4 weeks after FLT (85.7+/-1.6% of CD11b+/Gr-1+ monocytes were GFP+), and minimal alveolar macrophage repopulation was observed (9.5% GFP+). By 10 weeks following FLT, 48% of alveolar macrophages were GFP+ by immunostaining of macrophages on lung tissue sections, and 55.1 +/- 1.6% of lung lavage macrophages were GFP+ by fluorescein-activated cell sorter analysis. Clodronate treatment resulted in a significant increase in GFP+ alveolar macrophages 10 weeks after FLT. By immunostaining, 90% of macrophages were GFP+ on lung tissue sections and 87.5 +/- 1.1% GFP+ in lung lavage (compared with GFP-transgenic controls). The ability of newly recruited alveolar macrophages to clear Pseudomonas aeruginosa and activate nuclear factor-kappaB in response to Eschericia coli lipopolysaccharide demonstrated normal macrophage function. Optimizing this methodology provides an important tool for the study of specific genes and their contribution to alveolar macrophage function in vivo.  相似文献   
94.
This report describes an uncommon case of hypertrophic obstructive cardiomyopathy (HOCM) accompanying infundibular stenosis of the right ventricle treated by alcohol ablation therapy, in a 28-yr-old male patient presenting with dyspnea on exertion. HOCM with infundibular stenosis was detected by echocardiogram and cardiac catheterization and patient has dynamic obstructions of both ventricular outflow tracts. We performed alcohol ablation therapy to improve clinical symptoms and to relieve dynamic obstructions of both ventricular outflow tracts. This is the first case in which HOCM with infundibular stenosis of the right ventricle was treated by alcohol ablation therapy.  相似文献   
95.
96.
Scrotal leiomyomas with atypical bizarre nuclei are rare, which might be misdiagnosed as malignant tumor. We describe a case of scrotal bizarre leiomyoma in a 65-yr-old man. The tumor was a 1 cm-sized, well circumscribed, oval mass arising from the tunica dartos muscle. Histologically, it was formed by whorling bundles of fusiform cells with occasional atypical, pleomorphic nuclei and pseudo-inclusions. Mitosis was not found. Although morphologically atypical, scrotal bizarre leiomyomas take on a biologic behavior not different from that of conventional leiomyoma, they should be distinguished from leiomyosarcoma to avoid unnecessary treatment.  相似文献   
97.
Sulfonated polyrotaxanes (PRx-SO(3)'s), in which sulfonated alpha-cyclodextrins (alpha-CDs) were threaded onto the poly(ethylene glycol) (PEG) segments in a PEG-b-poly(propylene glycol) (PPG)-b-PEG triblock copolymer (Pluronic) capped with benzyloxycarbonyl (Z)-L-phenylalanine (Z-L-Phe), were prepared as a novel surface-modifying biomaterial. Surface modification of the polyurethane (PU) was carried out by blending the PRx-SO(3)'s with a PU solution, followed by solution casting. The incorporated PRx-SO(3)'s led to the enhanced hydrophilicity by changing the surface properties of the PU matrix. Modified PUs showed the stable entrapment of the PRx-SO(3)'s with little extraction into water and enhanced mechanical properties after exposure to water compared to the PU control. The incorporated PRx-SO(3)'s repelled the proteins and kept them from closely approaching the surface areas, prevented platelet activation by thrombin, and effectively repelled bacteria. These results suggest that both the supramolecular structure of the polyrotaxanes and exposure of the sulfonated groups onto the surfaces contribute to these phenomena. Thus, surface modification with PRx-SO(3)'s is suggested to be useful for the fabrication of biocompatible medical devices.  相似文献   
98.
Summary: The blends of poly(hydroxyether sulfone) (PHES) with poly(N‐vinylpyrrolidone) (PVPy) were investigated by means of differential scanning calorimetry (DSC) and FTIR spectroscopy. The miscibility of the blend system was established on the basis of the thermal analysis results. DSC showed that the PHES/PVPy blends prepared by casting from N,N‐dimethylformamide (DMF) possessed single, composition‐dependent glass transition temperatures, indicating that the blends are miscible in the entire composition. The experimental glass transition temperatures have higher values than those calculated on the basis of additive behavior; the variation of the glass transition temperatures of the blends was accounted for by the Kwei equation. FTIR studies indicate that competitive hydrogen bonding interactions exist upon addition of PVPy to the system, which were involved in the self‐ and cross‐association, i.e., ? OH···O?S, ? OH···OH of PHES and ? OH···O?C< of PVPy. The FTIR spectra in the range of the sulfonyl stretching vibrations showed that the hydroxyl‐associated sulfonyl groups are partially “set free” upon addition of PVPy to the system. The IR spectroscopic investigation of both the model compounds and the PHES/PVPy blends suggests that the strength of the hydrogen bonding interactions in the blend system increases in the following order: ? OH···O?S, ? OH···OH and ? OH···O?C<.

Plot of glass transition temperature for PHES/PVPy blends as a function of weight fraction of PVPy. The prediction of the Kwei equation yields the values of k = 1 and q = 122.  相似文献   

99.
OBJECTIVE AND DESIGN: To demonstrate the role of bile acids in immune modulation we examined the ability of select bile acids to inhibit leukocyte migration and chemoattractant receptor function. MATERIALS: To elucidate this mechanism, we employed primary human monocytes, neutrophils and cell lines transfected to express either the high affinity fMLP receptor (FPR) or the low affinity fMLP receptor like 1 (FPRL1). Treatment: Cells were treated with chenodeoxycholic acid (CDCA) and related bile acids in a 0-400 micromolar range. METHOD: Cell viability, chemotaxis and calcium flux analysis were preformed. RESULTS: We observed that pathophysiological levels (< or = 150 micromolar) of CDCA competitively inhibited 3H-fMLP binding to human monocytes, FPR and FPRL1 transfected cells. Additionally, CDCA reduced both the chemotactic and calcium flux responses induced by fMLP or "W" peptide. Further, CDCA inhibited anti-FPR antibody binding to monocytes. CONCLUSIONS: CDCA selectively inhibited human leukocyte chemotaxis and calcium flux induced by fMLP, but not other chemoattractants, suggesting a mechanism for inhibition of inflammation and suppression of innate immune response.  相似文献   
100.
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