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排序方式: 共有2050条查询结果,搜索用时 14 毫秒
1.
2.
The cytotoxicity of extracts from rice cultures of five Fusarium avenaceum strains against the porcine epithelial kidney cell-line PK-15 was investigated using the Alamar Blue™ assay. After the identification of known fungal metabolites, cytotoxic extracts were fractionated using semi-preparative reversed-phase HPLC and normal phase LC, and the fractions were tested for cytotoxicity. In this way, two different groups of metabolites were identified as the major cytotoxic principles of the extracts. High concentrations of enniatins, especially enniatins B and B1, inhibited the metabolic activity of PK-15 cells. Furthermore, an unidentified metabolite, produced in high amounts by a strain that produced relatively small amounts of enniatins, was also found to be cytotoxic to PK-15 cells. This study shows that enniatins, a group of cyclic depsipeptides, which have been ignored as significant contributors to the toxicity of fungal extracts, may account for most of the observed effect for F. avenaceum. 相似文献
3.
Walking exercise in patients with intermittent claudication. Experience in routine clinical practice. 下载免费PDF全文
Marie-Louise Bartelink Henri E J H Stoffers Cornelis J Biesheuvel Arno W Hoes 《The British journal of general practice》2004,54(500):196-200
BACKGROUND: In patients with intermittent claudication, exercise in the form of walking is effective in reducing pain and maximising achievable walking distance. However, data are lacking on the implementation of walking exercise in these patients. AIMS: To explore the current behaviour and views of patients with intermittent claudication towards taking walking exercise. DESIGN OF STUDY: Postal questionnaire and focus group meetings. SETTING: Two academic general practice networks (Utrecht and Maastricht Universities) in The Netherlands. METHOD: Three hundred and seventy-five patients with intermittent claudication, selected from the files of general practitioners participating in two academic general practice networks, were sent a postal questionnaire; 216 (58%) were returned. Nine of these responders also attended a focus group meeting. RESULTS: Seventy per cent (151/216) of the patients reported having received advice about walking exercise. If specified, the advice given most often recommended walking in the local neighbourhood (56%, 84/151). Fifty-two per cent (113/216) of all patients actually performed walking exercise and only 32%of them received any kind of supervision. Among the barriers for taking walking exercise, 'comorbidity', 'lack of (specific) advice' and 'lack of supervision' were often mentioned. Among the stimuli to start and continue walking, 'following the doctor's advice', 'relief of complaints' and 'a better general condition' were often mentioned by patients. CONCLUSIONS: Walking exercise was not carried out by almost half of patients with intermittent claudication in this study. Lack of specific advice and supervision were found to be important barriers to taking walking exercise. 相似文献
4.
Arno Krug 《Virchows Archiv : an international journal of pathology》1970,351(1):33-40
Zusammenfassung Bei 3 Patienten, die unmittelbar nach herzchirurgischen Eingriffen verstarben, konnte durch Bestimmung der Wasserstoffionenkonzentration [H+] mit Indicatorpapier am Gefrierschnitt des Herzens 1–2 Std nach dem Tod jeweils eine umschriebene ischämische Schädigung nachgewiesen und das Alter des frischen Herzinfarktes anhand der veränderten [H+] festgestellt werden. Innerhalb der ersten 1–2 Std nach Beginn der Herzmuskelischämie war die [H+] in dem ischämisch geschädigten Bereich erhöht (pH<6.0). Anschließend wies der Infarktbereich, im Randbereich beginnend, eine erniedrigte Wasserstoffionenkonzentration (pH 7.4–7.5) auf.Im Zusammenhang mit der erniedrigten [H+] ließ sich mit der Perjodsäure Schiff-(PAS-) Reaktion sogenanntes PAS-positives diastaseresistentes Material im Myokard nachweisen. Beim enzymhistochemischen Succinodehydrogenasenachweis fand sich in einem 7–8 Std alten Infarkt eine verstärkte Enzymreaktion.
Mit Unterstützung der Deutschen Forschungsgemeinschaft.
Vorgetragen auf der Thoraxchirurgischen Arbeitstagung, Februar 1970 in Bad Nauheim. 相似文献
The demonstration of acute human cardiac infarction by determining the hydrogen ion concentration of the myocardium with indicator paper
Summary In three patients who died immediately after surgical procedures on the heart it was possible one—two hours after death to demonstrate with indicator paper on frozen sections of myocardium a circumscribed ischemic lesion and to determine the age of the infarction from the changed hydrogen ion concentration. Within the first one—two hours after the onset of ischemia the hydrogen ion concentration in the area of ischemic damage is increased (pH<6.0). Subsequently the infarcted area, beginning in the border zone, shows a decreased hydrogen ion concentration (pH appr. 7.4–7.5).As to the decreased hydrogen ion concentration, it was possible with the periodic-acid-Schiff (PAS) reaction to demonstrate so-called PAS-positive diastase-resistant material in the myocardium. The enzymhistochemical succinodehydrogenase test showed an increased enzyme reaction in an infarction which was 7–8 hours old.
Mit Unterstützung der Deutschen Forschungsgemeinschaft.
Vorgetragen auf der Thoraxchirurgischen Arbeitstagung, Februar 1970 in Bad Nauheim. 相似文献
5.
Arnoŝt Bass Karel Vondra Ratmír Rath Václav Vítek 《Pflügers Archiv : European journal of physiology》1975,354(3):249-255
1. The following enzyme activities were estimated in needle-biopsy samples of the lateral part of the human quadriceps femoris muscle: triosephosphate dehydrogenase (TPDH), lactate dehydrogenase (LDH), NAD : glycerol-3-phosphate dehydrogenase (GPDH), hexokinase (HK), NAD: malate dehydrogenase (MDH), citrate synthase (CS) and hydroxyacyl-CoA dehydrogenase. 2. Although the enzyme activities in muscles of women were lesser than in those of men, no difference was found in the calculated enzyme activity ratios. There is thus no sex-dependent metabolic type-differentiation in this muscle. 3. The human quadriceps femoris is a low-activity muscle, in comparison with muscles of homoiotherm laboratory animals. The enzyme activity ratio of TPDH to CS, characterizing the glycolytic pyruvate formation to aerobic oxidative capacities, shows this muscle to be of an intermediate type in this respect, similarly as the extensor digitorum longus of the rat. The relatively very high capacity of glucose phosphorylation (HK), the high aerobic regeneration of cytoplasmic dehydrogenated NAD (GPDH) and the very low anaerobic regeneration (LDH), show the unusually high proportion of carbohydrates (glucose) which can be broken down aerobically. 相似文献
6.
The model of recurrent herpes labialis was selected to evaluate the role played by stress in increasing susceptibility to illness. Initially, 35 paid volunteers with recurrent herpes were enrolled in the project. Compared with 35 age- and sex-matched controls, this group demonstrated a familial predisposition for recurrent herpes labialis. Eighteen subjects without confounding variables known to precipitate recurrent herpes infections completed a pretested "stress" questionnaire during a dormant and again during an active stage of infection. In the week prior to the appearance of a recurrence, this group experienced increased daily hassles, increased stressful life events, and higher state anxiety. These findings are discussed in the broader context of stress-associated disease with some speculations concerning a possible biologic mechanism, which involves modulations of T-lymphocyte function. 相似文献
7.
Remco J.P. Doodkorte Alex K. Roth Jacobus J. Arts L.M. Arno Lataster Lodewijk W. van Rhijn Paul C. Willems 《The spine journal》2021,21(5):855-864
BACKGROUND CONTEXTAdult spinal deformity patients treated operatively by long-segment instrumented spinal fusion are prone to develop proximal junctional kyphosis (PJK) and failure (PJF). A gradual transition in range of motion (ROM) at the proximal end of spinal instrumentation may reduce the incidence of PJK and PJF, however, previously evaluated techniques have not directly been compared.PURPOSETo determine the biomechanical characteristics of five different posterior spinal instrumentation techniques to achieve semirigid junctional fixation, or “topping-off,” between the rigid pedicle screw fixation (PSF) and the proximal uninstrumented spine.STUDY DESIGNBiomechanical cadaveric study.METHODSSeven fresh-frozen human cadaveric spine segments (T8–L3) were subjected to ex vivo pure moment loading in flexion-extension, lateral bending and axial rotation up to 5 Nm. The native condition, three-level PSF (T11–L2), PSF with supplemental transverse process hooks at T10 (TPH), and two sublaminar taping techniques (knotted and clamped) as one- (T10) or two-level (T9, T10) semirigid junctional fixation techniques were compared. The ROM and neutral zone (NZ) of the segments were normalized to the native condition. The linearity of the transition zones over three or four segments was determined through linear regression analysis.RESULTSAll techniques achieved a significantly reduced ROM at T10-T11 in flexion-extension and axial rotation relative to the PSF condition. Additionally, both two-level sublaminar taping techniques (CT2, KT2) had a significantly reduced ROM at T9-T10. One-level clamped sublaminar tape (CT1) had a significantly lower ROM and NZ compared with one-level knotted sublaminar tape (KT1) at T10-T11. Linear regression analysis showed the highest linear correlation between ROM and vertebral level for TPH and the lowest linear correlation for CT2.CONCLUSIONSAll studied semirigid junctional fixation techniques significantly reduced the ROM at the junctional levels and thus provide a more gradual transition than pedicle screws. TPH achieves the most linear transition over three vertebrae, whereas KT2 achieves that over four vertebrae. In contrast, CT2 effectively is a one-level semirigid junctional fixation technique with a shift in the upper rigid fixation level. Clamped sublaminar tape reduces the NZ greatly, whereas knotted sublaminar tape and TPH maintain a more physiologic NZ. Clinical validation is ultimately required to translate the biomechanics of various semirigid junctional fixation techniques into the clinical goal of reducing the incidence of proximal junctional kyphosis and failure.CLINICAL SIGNIFICANCEThe direct biomechanical comparison of multiple instrumentation techniques that aim to reduce the incidence of PJK after thoracolumbar spinal fusion surgery provides a basis upon which clinical studies could be designed. Furthermore, the data provided in this study can be used to further analyze the biomechanical effects of the studied techniques using finite element models to better predict their post-operative effectiveness. 相似文献
8.
Arno S 《The Journal of orthopaedic and sports physical therapy》1990,12(6):237-242
This case study introduces a clinical measurement of patellar glide, tin, and rotation, and defines a quantitative measurement called the A angle. An 11-year-old female with patellofemoral pain is treated using a protocol that includes a technique to align the patella through taping, stretching the lateral structures, and strengthening using functional training and isokinetics, with emphasis on the vastus medialis obliquus. The A angle may be a sensitive clinical indicator of patellofemoral pathomechanics. J Orthop Sports Phys Ther 1990;12(6):237-242. 相似文献
9.
Arend Mosaterd Jaap W. Deckers Arno W. Hoes Angelique Nederpel Albert Smeets David T. Linker Diederick E. Grobbee 《European journal of epidemiology》1997,13(5):491-502
Several scores based on symptoms and signs have been developed to assess the presence of heart failure. The goal of this study was to compare six heart failure scores in non-hospitalised subjects and to determine their usefulness in population based research. The scores were applied to 54 participants of a population based study. All underwent a complete medical examination, including chest X-ray, electrocardiography and Doppler echocardiography. Using all information available, a cardiologist, unaware of the results of the scores, clinically classified participants as having no, possible or definite heart failure. Sensitivity, specificity, predictive values and receiver operating characteristics were calculated, using the cardiologist's assessment as a gold standard. The cardiologist judged definite or possible heart failure to be present in 17 persons. All scores had a high sensitivity for the detection of definite heart failure, whereas the study of men born in 1913 and Walma's score had the highest sensitivity for the combination of possible and definite heart failure. Gheorgiade's and the Boston score had the highest positive predictive values. In conclusion, five of the six scores we studied are broadly similar in the detection of heart failure. The men born in 1913 score relies heavily on the assessment of dyspnea, resulting in a relatively large number of false positives. Although the scores are useful in detecting manifest heart failure, objective measurements of cardiac function appear necessary to reduce the false positive rate and accurately detect early stages of heart failure. 相似文献
10.
Hans Christian Blossey Hans Helge Bartsch Dietrich Kanne Johannes Koebberling Gerhard Arno Nagel 《Cancer chemotherapy and pharmacology》1982,8(1):77-81
Summary Oral MPA 1.5 g/day leads to plasma concentrations between 1 and 12 g/ml, with a broad intra-and interindividual variance. The plateau state is reached in between 4 and 16 days. Plasma concentrations in the plateau state are very sensitive to dose modifications. After cessation of administration, the decline in plasma levels seems to proceed in two phases, with half-times of about 20 h and 4 days. Extraction procedures reveal no benefit in discriminating between MPA and its metabolites. 相似文献