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991.
Induction of interleukin-2 (IL-2) responsiveness by Dermatophagoides farinae (Df)-stimulated lymphocytes from children with asthma was markedly suppressed after the addition of culture supernatants from Df-stimulated normal T cells. Ovalbumin (OVA)-induced IL-2 responsiveness of lymphocytes from patients with hen-egg allergy was not suppressed by the supernatant from Df-stimulated T cells, indicating the antigenic specificity of the effect. Patients' lymphocytes whose IL-2 responsiveness was decreased still expressed Tac antigen (low-affinity IL-2 receptors) but, in contrast to the patients' original lymphocytes, did not absorb or respond to IL-2, suggesting the loss of high-affinity IL-2 receptors (p55/p75) from these cells. The supernatant from Df-stimulated normal T cells from one individual did not necessarily suppress the response of all patients tested, indicating the existence of some allogeneic barrier between the factor(s) and patients' lymphocytes.  相似文献   
992.
The annual multicenter studies on isolated bacteria from infections in general surgery and their antimicrobial susceptibility have been conducted in Japan since July 1982. This paper describes the results obtained in fiscal 1998 (from April 1998 to March 1999). The number of cases investigated as objectives was 225 for one year. A total of 429 strains (121 strains from primary infections and 308 strains from postoperative infections) were isolated from 183 cases (81.3% of total cases). In primary infections, the isolation rates of anaerobes and Escherichia coli were higher than in postoperative infections, while in postoperative infections, those of Gram-positive aerobes and Pseudomonas aeruginosa were higher than in primary infections. On the whole, among Gram-positive aerobes, the isolation rate of Enterococcus faecalis was the highest, followed by Staphylococcus aureus with high frequency in isolation from postoperative infections. Among Gram-positive anaerobes, Peptostreptococcus spp. and Streptococcus spp. were predominantly isolated. Among Gram-negative aerobes, E. coli, P. aeruginosa, Klebsiella pneumoniae and Enterobacter cloacae were frequently isolated. Among Gram-negative anaerobes, Bacteroides fragilis group was the majority of isolates. In primary infections, the percentage of Gram-negative aerobes has gradually increased since fiscal 1995 or 1996 with these years as the turning point, while those of Gram-positive and Gram-negative anaerobes have gradually declined. In postoperative infections, the percentage of Gram-negative anaerobes has increased continuously since the mid-1980s. The percentage of MRSA among S. aureus rose to 89.7%, which was the highest level since the beginning of this study. The susceptibilities of B. fragilis, which did not show apparent changes, were recognized to have decreased against cephems in fiscal 1998. Among other bacteria in B. fragilis group, development of resistance to cephems has continued on a long-term basis since the mid-1980s. E. coli and K. pneuminiae have obviously not changed in susceptibilities, however, the susceptibilities of isolated strains in fiscal 1998 against high-generation cephems, oxacephems and monobactams have declined. We found neither vancomycin-resistant nor teicoplanin-resistant strains of S. aureus and Enterococcus spp.  相似文献   
993.
994.
In an epizootiologic survey of 122 rodents captured in Vladivostok, Russia, antibodies positive for hantavirus were found in Apodemus peninsulae (4/70), A. agrarius (1/39), and Clethrionomys rufocanus (1/8). The hantavirus sequences identified in two seropositive A. peninsulae and two patients with hemorrhagic fever with renal syndrome (HFRS) from the Primorye region of Far East Russia were designated as Solovey and Primorye, respectively. The nucleotide sequences of the Solovey, Primorye, and Amur (obtained through GenBank) sequences were closely related (>92% identity). Solovey and Primorye sequences shared 84% nucleotide identity with the prototype Hantaan 76-118. Phylogenetic analysis also indicated a close relationship between Solovey, Primorye, Amur, and other viruses identified in Russia, China, and Korea. Our findings suggest that the Korean field mouse (A. peninsulae) is the reservoir for a hantavirus that causes HFRS over a vast area of east Asia, including Far East Russia.  相似文献   
995.
Endothelial cells release endothelium-derived hyperpolarizing factor (EDHF), as well as nitric oxide (NO). It has recently been suggested that 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) improve NO-mediated endothelial function, partially independently of their cholesterol-lowering effects. It is, however, unclear whether statins improve EDHF-mediated responses. Eight-month-old stroke-prone spontaneously hypertensive rats (SHRSP) were treated with fluvastatin (10 mg/kg per day) for 1 month. Age-matched, normotensive Wistar Kyoto (WKY) rats served as controls. Both EDHF- and NO-mediated relaxations were impaired in SHRSP compared with WKY rats. Fluvastatin treatment did not affect blood pressure and serum total cholesterol. The acetylcholine (ACh)-induced, EDHF-mediated hyperpolarization in mesenteric arteries did not significantly differ between fluvastatin-treated SHRSP and untreated SHRSP and the responses in both groups were significantly smaller compared with those of WKY rats. Endothelium-derived hyperpolarizing factor-mediated relaxations, as assessed by the relaxation to ACh in mesenteric arteries contracted with noradrenaline in the presence of N(G)-nitro-l-arginine and indomethacin, were virtually absent and similar in both SHRSP groups. In contrast, NO-mediated relaxation, as assessed by the relaxation in response to ACh in rings contracted with 77 mmol/L KCl, was improved in fluvastatin-treated SHRSP compared with untreated SHRSP (maximum relaxation in control and fluvastatin groups 42.0 +/- 5.2 and 61.2 +/- 3.8%, respectively; P < 0.05). Hyperpolarization and relaxation in response to levcromakalim, an ATP-sensitive K(+) channel opener, were similar between the two SHRSP groups. These findings suggest that fluvastatin improves NO-mediated relaxation, but not EDHF-mediated hyperpolarization and relaxation, in SHRSP. Thus, the beneficial effects of the statin on endothelial function may be mainly ascribed to an improvement in the NO pathway, but not EDHF.  相似文献   
996.
OBJECTIVE: The second window of protection (SWOP) following brief coronary artery occlusion begins at 24 h and may last up to 72 h and occurs via many unknown mechanisms. We investigated the role of the mitochondrial permeability transition pore (PTP), a non specific pore in the inner membrane of the mitochondria in this phenomenon. METHODS: Ischemic preconditioning (IP) was induced in Wistar rats by left coronary artery occlusion (four, 3-min episodes separated by 10 min of reperfusion) on day 1. On day 2, ischemia was induced with 30 min of ischemia and 120 min of reperfusion in IP and control rats. RESULTS: IP rats showed decreased myocardial infarction (MI) area vs. non-IP control rats (15.32 vs. 45.6%). Furthermore, IP rats had preserved cardiac function (heart rate, rate pressure product, coronary flow and aortic flow) and myocardial ATP (P<0.03), decreased tissue water content (73.2 vs. 90.6%), increased expression of Bcl-2, and less mitochondrial swelling, cytochrome C release and apoptosis (2.6 vs. 12.4%) when compared to sham-operated rats. Activation of the permeability transition pore with PTP activators lonidamine (10 mg/kg body weight) or atractyloside (5 mg/kg body weight) before the sustained ischemia on day 2 resulted in complete abolition of SWOP-mediated cytoprotective effects. These agents had no effect on the cytoprotective effects that took place during the first window of preconditioning. CONCLUSION: The cytoprotective effects of SWOP are dependent on PTP activation state and may involve upregulation of Bcl-2 expression.  相似文献   
997.
Bacteria isolated from infections in abdominal surgery during the period from April 2008 to March 2009 were investigated in a multicenter study in Japan, and the following results were obtained. In this series, 712 strains including 18 strains of Candida spp. were isolated from 173 (80.5%) of 215 patients with surgical infections. Three hundred and sixty-six strains were isolated from primary infections, and 346 strains were isolated from postoperative infections. From primary infections, anaerobic Gram-negative bacteria were predominant, followed by aerobic Gram-negative bacteria, while from postoperative infections aerobic Gram-positive bacteria were predominant, followed by anaerobic Gram-negative bacteria. Among aerobic Gram-positive bacteria, the isolation rate of Enterococcus spp. was highest, followed by Streptococcus spp., and Staphylococcus spp. in this order, from primary infections, while Enterococcus spp. was highest, followed by Staphylococcus spp. from postoperative infections. Among aerobic Gram-negative bacteria, Escherichia coli was the most predominantly isolated from primary infections, followed by Klebsiella pneumoniae and Pseudomonas aeruginosa, in this order, and from postoperative infections, P aeruginosa was most predominantly isolated, followed by E. coli, Enterobacter cloacae, and K. pneumoniae. Among anaerobic Gram-positive bacteria, the isolation rate of Eggerthella lenta was the highest from primary infections, followed by Parvimonas micra, Streptococcus constellatus and Gemella morbillorum, and from postoperative infections, E. lenta was most predominantly isolated. Among anaerobic Gram-negative bacteria, the isolation rate of Bacteroides fragilis was the highest from primary infections, followed by Bacteroides thetaiotaomicron, Bacteroides ovatus and Bilophila wadsworthia, and from postoperative infections, B. fragilis was most predominantly isolated, followed by B. thetaiotaomicron, B. wadsworthia and B. ovatus, in this order. In this series, we noticed no vancomycin-resistant methicillin-resistant S. aureus, and Enterococcus spp., nor multidrug-resistant P aeruginosa. We should carefully follow up B. wadsworthia which was resistant to various antibiotics, and also Bacteroides spp. which was resistant to many beta-lactam antibiotics.  相似文献   
998.
Background/Purpose Endoscopic drainage of pancreatic pseudocysts using transpapillary and transmural approaches has been reported. In this study, endoscopic nasopancreatic drainage (ENPD) and pancreatic stenting were performed in patients with pseudocyst and abscess associated with acute pancreatitis, and the usefulness and problems of the procedures were investigated. Methods After endoscopic retrograde pancreatography was done, ENPD and/or pancreatic stenting were performed in 13 patients with pancreatitis and pseudocyst or abscess that communicated with the main pancreatic duct. Results ENPD was performed in seven patients, and was effective in all five patients with cysts: the cysts disappeared or shrank. However, the condition in the two patients with abscess was unchanged, and percutaneous drainage was performed. Stenting was carried out in six patients, and the cyst disappeared or pancreatitis was improved in all six. The stent was removed from two patients, but no recurrence has been noted so far. Conclusions ENPD and stenting are effective therapeutic choices for acute and chronic pancreatitis and pseudocysts, and they are superior to percutaneous drainage to avoid pancreatic fistula, but they may not be effective for pancreatic abscess. Selection of therapeutic methods corresponding to individual cases is important.  相似文献   
999.
PURPOSE: We reviewed findings on the pathogenic role of Mycoplasma genitalium in nongonococcal urethritis and the treatment of men with M. genitalium positive nongonococcal urethritis. MATERIALS AND METHODS: We reviewed literature selected from peer reviewed journals listed in MEDLINE and from resources cited in those articles from 1967 to January 2001. RESULTS: M. genitalium was first isolated from 2 men with nongonococcal urethritis and thereafter it was shown to cause urethritis in subhuman primates inoculated intraurethrally. This mycoplasma has been detected significantly more often in patients with acute nongonococcal urethritis, particularly in those with nonchlamydial nongonococcal urethritis, than in those without urethritis. The prevalence of M. genitalium positive nonchlamydial nongonococcal urethritis is 18.4% to 45.5% of all nonchlamydial nongonococcal urethritis cases. In addition, the persistence of M. genitalium in the urethra after antimicrobial chemotherapy is associated with persistent or recurrent nongonococcal urethritis. M. genitalium is highly susceptible to tetracycline, macrolide and some new fluoroquinolones. The regimen of 100 mg. doxycycline orally twice daily for 7 days, which is recommended for chlamydial nongonococcal urethritis, seems to be effective for M. genitalium positive nongonococcal urethritis, although clinical data to substantiate this regimen are limited. CONCLUSIONS: The various results reported to date tend to support the proposition that M. genitalium is a pathogen of nongonococcal urethritis. However, currently diagnostic methods for this important mycoplasma are not available in clinical practice. Because of the possible association of the posttreatment presence of M. genitalium in the urethra with persistent or recurrent nongonococcal urethritis, eradication of this mycoplasma from the urethra is essential for managing M. genitalium positive disease. However, clinical data on treating M. genitalium positive nongonococcal urethritis are extremely limited. Thus, further studies are required to develop new diagnostic methods that would be available in clinical settings and establish a new treatment algorithm for nongonococcal urethritis, including M. genitalium positive disease.  相似文献   
1000.
Novel acyl coenzyme A:cholesterol acyltransferase (ACAT) inhibitor pactimibe was administered as the sulfate salt form to 3-month-old homozygous Watanabe heritable hyperlipidemic (WHHL) rabbits at doses of 0, 10, or 30 mg/kg for 32 weeks. Pactimibe (10 and 30 mg/kg) tended to reduce intimal thickening in thoracic aortic lesions (294+/-39 and 276+/-32 microm, respectively, versus 313+/-37 microm control), histopathological examination revealing significantly increased smooth muscle cell area (12.0+/-0.9% and 12.3+/-0.5%, P<0.05, respectively, versus 9.7+/-0.8% control), significantly increased collagen fiber area (20.5+/-1.2% and 31.0+/-1.3%, P<0.05, respectively, versus 16.2+/-1.0% control), and tended to reduce macrophage infiltration (6.0+/-1.1% and 4.6+/-1.0%, respectively, versus 7.0+/-1.3% control). Pactimibe dose-dependently reduced cholesteryl ester content in thoracic and abdominal aortic lesions, and reduced free cholesterol content in the aorta versus control. Although pactimibe did not alter serum cholesterol levels in WHHL rabbits, it stabilized vulnerable plaque characterized with reduced cholesteryl ester content, enriched collagen fibers and increased smooth muscle cells, indicating potential as a treatment strategy for coronary heart disease.  相似文献   
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