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排序方式: 共有1337条查询结果,搜索用时 15 毫秒
1.
2.
Homogeneous and stable layers were deposited through allylamine plasma polymerization (75 W, 100 Pa, 15 min) onto poly[(3-hydroxybutyric acid)-co-(3-hydroxyvaleric acid)] (91 : 9 wt.-%) (P(HB-co-9%HV)) film surfaces, XPS analysis using take-off angles of 20° and 70° and performed 10 days and 20 days after plasma treatment gives information on the composition (in atom%) of the modified surface: C, 62.74; N, 19.60; O, 17.65. The unexpected oxygen percentage is weaker if argon plasma pretreatment (25 W, 40 Pa, 5 min) is applied. Then, a succinct mechanism is proposed. The study of changes in element ratios and binding energy values shows that the majority of incorporated functional groups seem to be amide and imine groups.  相似文献   
3.
Peripheral gangrene associated with Kawasaki disease.   总被引:3,自引:0,他引:3  
Three American infants with Kawasaki disease (KD) complicated by peripheral extremity gangrene are reported. Eight such patients (only 1 from Japan) have been reported previously. These 11 patients, infants less than 7 months old at onset of KD, are predominantly non-Asian. At least nine had associated giant coronary aneurysms, and eight had associated peripheral arterial aneurysms. In eight infants the diagnosis of KD was not established and therapy was not instituted until greater than or equal to 14 days after onset. Peripheral ischemia initially was noted 15-31 days after onset. Although the pathogenesis of this complication is not well understood, it likely includes some combination of local peripheral arteritis, arteriospasm, thrombosis peripherally and/or more proximally (e.g., in an axillary artery aneurysm), and cardiogenic shock. Treatment may include use of antiinflammatory agents such as salicylates and intravenous gamma globulin, vasodilative agents and/or methods, and thrombolytic and/or anticoagulant agents in an attempt to prevent the potentially devastating consequences of progressive gangrene.  相似文献   
4.
P. Mas  C. Gossard  J. Baucher 《ITBM》2006,27(3):141-148
The knee joint is composed of two articular systems: the femorotibial and femoropatellar joints. The femorotibial joint appears quite instable, with its two convexe femoral condyles on the planar tibial surface. Actually, a muscular and tendinous organization ensures stability during motion. The muscular extensor system, with quadriceps patella and patellar tendon, controls the forward sliding of the femoral condyles and provides the knee stability in the sagittal plane. The posterior internal/external capsular and muscular reinforcements, also called posterolateral/posteromedial corner, ensures stability during rotation in the frontal and horizontal planes. Nonetheless, it is necessary to add to this muscular organization, a powerful informative system where the cruciate ligaments of the knee assume the major role. Those ligaments still remain in tension and inform the nervous system in any motion of the knee. This functional organization allows both large flexion-extension and stability. This article shows as an example the functional organization of the femorotibial joint.  相似文献   
5.
Physical inactivity is associated with alteration of normal physiologic processes leading to muscle atrophy, reduced exercise capacity, insulin resistance, and altered energy balance. Bed rest studies in human beings using stable isotopes of amino acids indicate that muscle unloading decreases the turnover rates of muscle and whole-body proteins, with a prevailing inhibition of protein synthesis. In the fasting state, muscle and whole-body nitrogen loss was not accelerated during bed rest. In experimental postprandial states, the amino acid-mediated stimulation of protein synthesis was impaired, whereas the ability of combined insulin and glucose infusion to decrease whole-body proteolysis was not affected by muscle inactivity. Thus, an impaired ability of protein/amino acid feeding to stimulate body protein synthesis is the major catabolic mechanism for the effect of bed rest on protein metabolism. This suggests that a protein intake level greater than normal could be required to achieve the same postprandial anabolic effect during muscle inactivity. Metabolic adaptation to muscle inactivity also involves development of resistance to the glucoregulatory action of insulin, decreased energy requirements, and increased insulin and leptin secretion. These alterations may lead to the development of the metabolic syndrome that is defined as the association of hyperinsulinemia, dyslipidemia, hypertension, hyperglycemia, and abdominal obesity. This cluster of metabolic abnormalities is a risk factor for coronary artery disease and stroke. Evidence indicates that exercise training programs may counteract all of these abnormalities both in healthy sedentary subjects and in patients affected by a variety of chronic disease states.  相似文献   
6.
BACKGROUND: Equilibration of hemoglobin concentration after transfusion has been estimated to take about 24 hours, but some studies have shown that earlier measurements reflect steady-state values in persons who have not bled recently. This study was aimed at assessing the changes over time in hemoglobin concentration after transfusion in acutely anemic patients because of recent bleeding. STUDY DESIGN AND METHODS: Thirty-two normovolemic patients recovering from an acute bleeding episode who were no longer thought to be bleeding and who received a 2- unit red cell transfusion were studied. At baseline and 15, 30, 60, and 120 minutes and 24 hours after transfusion, hemoglobin concentration and hematocrit values were measured. RESULTS: The administration of 2 units of packed red cells elicited a 24-hour increase of 22.4 +/− 6.8 g per L in hemoglobin concentration. Hemoglobin values were not different at any of the defined posttransfusion times. Hematocrit levels experienced similar changes over time. Agreement between 15-minute and 24-hour values was excellent, as only 6 percent of patients exhibited a clinically significant difference (> 6 g/L) between the hemoglobin measurements. CONCLUSION: Hemoglobin and hematocrit values rapidly equilibrate after transfusion in normovolemic patients who are recovering from an acute bleeding episode. This fact would allow a rapid assessment of the effects of transfusion and of the recurrence of bleeding in patients remaining at risk.  相似文献   
7.
Abuse liability and acute subjective and psychomotor effects of flunitrazepam were assessed in ten methadone-maintained males with history of benzodiazepine and alcohol use, who voluntarily participated in a double-blind, controlled, cross-over, randomized clinical trial. There were six experimental sessions in which a single oral dose of flunitrazepam 1, 2, and 4 mg; triazolam 0.5 and 0.75 mg; and placebo was given. Evaluations included physiological measures; psychomotor performance tasks (simple reaction time, Digit Symbol Substitution Test, balance task, Maddox-wing device); and self-administered subjective effects questionnaires [Addiction Research Center Inventory (ARCI), Profile of Mood States (POMS), a series of visual analog scales (VAS)]. All drugs but flunitrazepam 1 mg caused an impairment of psychomotor tasks. Effects were more evident with the highest doses of both drugs. Only flunitrazepam 4 mg produced a significant decrease in balance time. Triazolam 0.75 mg induced increases in sedation measured by ARCI-PCAG, depression in POMS, and VAS-drowsiness scores. Flunitrazepam 4 mg caused euphoria-related effects as measured by increases in ARCI-MBG and “high” scores in the VAS. Our findings of flunitrazepam-induced euphoria in methadone-maintained subjects together with epidemiological evidence of flunitrazepam abuse by opioid dependents, suggest that it may be included in the group of benzodiazepines with a relatively high abuse potential. Received: 13 February 1998/Final version: 1 May 1998  相似文献   
8.
Thirty patients have been described with cytogenetically visible deletion of the short arm of chromosome 6. However, subtelomeric 6p deletion detected by subtelomeric specific probes has been reported only twice. We report two new patients with terminal 6p deletion detected by subtelomeric screening using fluorescence in situ hybridization (FISH). The two patients exhibited mental retardation, ocular abnormalities, hearing loss, and a characteristic facial appearance. Detailed FISH analyses with probes covering the distal 6p25 region estimated the size of the terminal deletions to approximately 5.5 Mb and approximately 4.8 Mb. Array-based comparative genomic hybridization (array CGH) was used to confirm the cryptic deletions. Most patients with subtelomeric defects lack a characteristic phenotype. However, some of the subtelomeric deletions result in a specific phenotype, which can direct the clinician towards the diagnosis. Submicroscopic 6p deletion appears to be a recognizable clinical phenotype, and this region should be thoroughly investigated with FISH probes, including at least a subtelomeric 6p probe and a probe covering FOXC1, for patients presenting with a characteristic facial appearance, ocular abnormalities, predominantly anterior-chamber eye defects, hearing loss, and mental retardation.  相似文献   
9.
D-003 is a mixture of long-chain aliphatic primary acids isolated from sugar cane wax with cholesterol-lowering effects proven in animals and healthy human volunteers. D-003 reduced serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) in rabbits, while it increased high-density lipoprotein cholesterol (HDL-C) and did not affect triglycerides. D-003 inhibits cholesterol synthesis by regulating, instead of directly inhibiting, hydroxamethylglutaryl-CoA (HMGCoA) reductase activity. Although the ways in which D-003 and statins inhibit cholesterol biosynthesis are not identical, the strong competitive inhibition of cholesterol biosynthesis induced by statins suggests that an enhanced decrease of LDL-C and TC caused by the combined therapy D-003 plus statins is not expected. Nevertheless, taking into account the differential effects of D-003 and statins in HDL-C and triglycerides in rabbits, potential benefits of such combined therapy on other lipid variables cannot been discarded. Fluvastatin is a statin that inhibits competitively HMGCoA reductase, like other members of this class. This study was undertaken to compare the cholesterol-lowering effects of D-003, fluvastatin and the combined therapy of D-003 plus fluvastatin in normocholesterolemic rabbits. Animals were randomly distributed into four groups of eight. One control group received the vehicle, two groups were treated with D-003 or fluvastatin at 5 mg/kg/day each, and the fourth group received the combined therapy of both drugs at 5 mg/kg/day each. Treatments were orally administered for 30 days. Body weight, food consumption and overall animal behavior were recorded to detect any warning sign resulting from combined therapy. After treatment, it was found that both D-003 and fluvastatin had significantly lowered LDL-C - D-003 by 81.5% (p < 0.01) and fluvastatin by 61.4% (p < 0.05). Combined therapy reduced LDL-C values (75.9%). Final values and percent changes reached in all groups were different from the control (p < 0.01). The reductions of TC were consistent with LDL-C decreases, so that D-003, fluvastatin and combined therapy significantly lowered TC by 48.4% (p < 0.01), 39.7% (p < 0.05) and 45.3%, respectively, values being different from those of the control (p < 0.01). The responses of LDL-C and TC to combined therapy were statistically similar, but less pronounced than those reached by D-003 alone. D-003 and combined therapy, but not fluvastatin alone, increased HDL-C (+21.5% and + 19.0%, respectively), these changes being significant versus the control (p < 0.05). In turn, fluvastatin and combined therapy, but not D-003 alone, lowered triglycerides (13.6% and 13.0%, respectively, p < 0.05 versus control). The effects of combined therapy on HDL-C were similar to those of D-003 alone, and the effects of combined therapy on triglycerides were similar to those of fluvastatin alone. The only advantage of combined therapy appears to be that it shows better effects on HDL-C than those of fluvastatin alone and better effects on triglycerides than D-003 alone. No significant changes in lipid profile were observed in the control group. All groups showed similar food consumption and body weight gain, health status being unaffected by the treatments. It is concluded that D-003 and fluvastatin at 5 mg/kg/day administered orally for 30 days to normocholesterolemic rabbits lowered LDL-C and TC, D-003 being more effective in increasing HDL-C and fluvastatin in lowering triglycerides. Combined therapy did not improve the response of LDL-C and TC with respect to monotherapies, but induced better responses of HDL-C and triglycerides than fluvastatin alone had on HDL-C or D-003 alone had on triglycerides.  相似文献   
10.
Testicular cancer is the most common neoplasia occurring in the young male population. The PEB (cisplatin, etoposide and bleomycin) adjuvant chemotherapy usually proposed after orchidectomy in non seminomatous tumours, and in metastatic seminomas, has improved the long-term survival of these patients. Following an azoospermic period, sperm cell recovery is generally observed after treatment delivery, but little is known about the genetic consequences on these new spermatozoa. To estimate the chromosomal consequences of this chemotherapy on sperm cells during the period of recovery of spermatogenesis, sperm cell aneuploidy was studied in testicular cancer patients, at 6-18 months after PEB adjuvant chemotherapy delivery, using fluorescence in-situ hybridization (FISH) of chromosomes 7, 16, 18, X and Y with specific DNA probes. A significant increase in the frequency of diploidy and disomy for chromosomes 16, 18 and XY was observed in treated patients compared with a healthy control group. Spermatozoa aneuploidy occurring during the spermatogenesis recovery period might be a possible side effect of the PEB regimen. Thus, practitioners should be advised to provide counselling about the need for an appropriate duration of contraception. Moreover, genetic counselling should be offered in cases of pregnancy occurring soon after the end of chemotherapy.  相似文献   
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