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81.
82.
J. J. Visser J. E. Hoogkamer M. F. Bobbert P. A. Huijing 《European journal of applied physiology》1990,61(5-6):453-460
Summary Lengths of muscle tendon complexes of the quadriceps femoris muscle and some of its heads, biceps femoris and gastrocnemius muscles, were measured for six limbs of human cadavers as a function of knee and hip-joint angles. Length-angle curves were fitted using second degree polynomials. Using these polynomials the relationships between knee and hip-joint angles and moment arms were calculated. The effect of changing the hip angle on the biceps femoris muscle length is much larger than that of changing the knee angle. For the rectus femoris muscle the reverse was found. The moment arm of the biceps femoris muscle was found to remain constant throughout the whole range of knee flexion as was the case for the medial part of the vastus medialis muscle. Changes in the length of the lateral part of the vastus medialis muscle as well as the medial part of the vastus lateralis muscle are very similar to those of vastus intermedius muscle to which they are adjacent, while those changes in the length of the medial part of the vastus medialis muscle and the lateral part of the vastus lateralis muscle, which are similar to each other, differ substantially from those of the vastus intermedius muscle. Application of the results to jumping showed that bi-articular rectus femoris and biceps femoris muscles, which are antagonists, both contract eccentrically early in the push off phase and concentrically in last part of this phase. 相似文献
83.
M. R. Visser I. M. Hoepelman H. Beumer M. Rozenberg-Arska J. Verhoef 《European journal of clinical microbiology & infectious diseases》1989,8(12):1061-1064
The in vitro antimicrobial activity of the new carbapenem meropenem (SM-7338) was determined by an agar dilution method in comparison with imipenem, ticarcillin/calvulanic acid, ceftazidime and the fourth-generation cephalosporin cefepime (BMY 28142). Meropenem showed superior activity againstEnterobacteriaceae (MIC900.06 mg/l) and against non-fermentative gram-negative rods, with the exception ofXanthomonas maltophilia. Meropenem had excellent activity against beta-lactamase-producingHaemophilus influenzae andNeisseria gonorrhoeae, and against theBacteroides fragilis group. Imipenem was slightly more active then meropenem against gram-positive cocci especiallyEnterococcus faecalis. 相似文献
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Tissue distribution of restricted leukocyte common antigens. A comprehensive study with protein- and carbohydrate-specific CD45R antibodies 总被引:3,自引:0,他引:3
R Lai L Visser S Poppema 《Laboratory investigation; a journal of technical methods and pathology》1991,64(6):844-854
A panel of monoclonal antibodies, specific for either protein or carbohydrate components of the leukocyte common antigen (LCA), were used to characterize the expression pattern of different variants of this antigen complex. Immunohistochemical and flow cytometric analysis was carried out on human lymphoid tissues from different anatomical compartments. We found that variations in terminal sialic acid or O-linked sugar moieties were associated with drastic differences in reactivity with some of the CD45R antibodies. For example, the carbohydrate determinants recognized by MT2 (CD45RA) and 2B11 (CD45) were not or were very weakly expressed on germinal center cells, whereas the carbohydrate determinant recognized by MT3 (CD45RB) was not expressed on the majority of mantle zone B cells. On the other hand, KiB3 (CD45RA) reacted with a protein determinant that is normally only exposed on mantle zone B cells but can be uncovered on marginal zone B cells and the CD45RA-positive T-cell subpopulation by enzymatic treatment. The findings suggest that differential biosynthesis and expression of the carbohydrate components of LCA are important mechanisms to generate additional LCA heterogeneity. Similar to the differential usage of the variable region, the exact carbohydrate composition is also linked to the stage of cell development. Heterogeneity in carbohydrate composition of the extracellular domain of LCA appears to enable interactions with different ligands, thereby holding the key to the regulation of LCA cytoplasmic tyrosine phosphatase activity. 相似文献
86.
The ineffectiveness of community‐based interventions can often be traced to problems that occur during implementation. In this study, we outline the implementation of a human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) prevention program in an educational setting in South Africa. An action research approach was used in the implementation of the intervention and a process and outcome evaluation, integrating qualitative and quantitative research methods, was made. The research illustrated the various levels of interaction in the community and the complexity of the processes involved in the implementation of interventions to facilitate community change. Social ecological theory, systems theory, and the social constructional approach are used to clarify the complexities of the implementation of community interventions. © 2004 Wiley Periodicals, Inc. J Comm Psychol 32: 145–165, 2004. 相似文献
87.
I. Kitayama A. M. Janson K. Fuxe L. F. Agnati A. Cintra S. O. ögren A. HÄrfstrand P. Eneroth T. Tsutsumi G. Jonsson H. W. M. Steinbusch T. J. Visser 《Journal of neural transmission (Vienna, Austria : 1996)》1987,70(3-4):251-285
Summary Groups of male rats were treated for a period of 14 days with imipramine (10mol/kg) given twice daily. Separate groups of rats received a single dose treatment using the same dose and experimental design as for the repeated treatment. Employing the avidin-biotin immunoperoxidase technique for immunohistochemistry 5-hydroxytryptamine (5-HT)-, substance P (SP)- and thyrotropin releasing hormone (TRH)-like immunoreactivities (IRs) were visualized in consecutive coronal sections of the brain stem and of the spinal cord. The IRs were studied by means of morphometric and microdensitometric procedures using automatic image analysis on profiles representing nerve terminal networks of the ventral horn of the cervical and lumbar enlargements of the spinal cord as well as their coexistence (5-HT/SP and 5-HT/TRH). With the same technique 5-HT IR was measured in the 5-HT nerve cell groups of the medulla oblongata (B 1, B 2, B 3) and of the nucleus raphe dorsalis (B 7) of the midbrain. In addition 5-HT and 5-hydroxyindolacetic acid (5-HIAA) levels were measured in the ventral and dorsal horns of the cervical and lumbar enlargements of the spinal cord using high performance liquid chromatography (HPLC). In the same parts of the spinal cord SP IR was studied by means of radioimmunoassay (RIA).The microdensitometric studies showed that chronic, but not acute, imipramine treatment selectively increased SP IR in the 5-HT/SP/TRH costoring nerve terminals of the medial part of the ventral horn in both the cervical and the lumbar enlargements. Furthermore, quantitative analysis of the entity of coexistence in the 5-HT nerve terminal networks of these areas showed that all the 5-HT nerve terminals contained SP and TRH IRs and that this phenomenon remained after acute and chronic imipramine treatment. The microdensitometric studies on the 5-HT nerve cell groups of the medulla oblongata and of the nucleus raphe dorsalis demonstrated that chronic, but not acute, imipramine treatment selectively increased 5-HT IR in the nerve cell bodies of the lateral part of group B 3 as evaluated from the median grey values. Acute, but not chronic, imipramine treatment significantly increased the field area of 5-HT IR of nerve cell bodies in group B 7, reflecting an increase in the mean profile area of the 5-HT IR nerve cell body profiles. Instead, the mean profile area of 5-HT IR cell bodies of group B 1 was acutely reduced by imipramine.The biochemical studies demonstrated that chronic imipramine treatment selectively reduced 5-HT utilization in the ventral horn of the spinal cord and selectively increased SP IR in the dorsal horn of the lumbar enlargement.In view of these observations it is suggested that chronic imipramine treatment specifically increases SP IR in the 5-HT/SP/TRH costoring nerve terminals of the ventral horn probably related to reduced SP release and reduced 5-HT utilization in these terminals. The results obtained in group B 7 may be explained by a regulation by the3H-imipramine raphe binding sites of fast axonal transport, an influence which may have therapeutic consequences. This mechanism may also be responsible for the increase in 5-HT IR seen upon chronic imipramine treatment in the lateral part of the 5-HT nerve cell body group B 3. Such an effect may lead to a metabolic down-regulation of group B 7, having a possible role for the antidepressant activity of imipramine. The reduction of the mean profile area of 5-HT IR cell bodies of group B 1 seen in the acute treatment can possibly be caused by, noradrenaline (NA) uptake inhibition in inhibitory NA terminals innervating the B 1 group. These results also illustrate the heterogeneities in the responses of the 5-HT nerve cell groups to antidepressant treatment. The ability of chronic imipramine treatment to increase SP IR in the dorsal horn of the lumbar enlargement may reflect the existence of a monoamine-SP interaction in the substantia gelatinosa due to the NA and/or 5-HT uptake blocking activity of imipramine. The existence of such an interaction may help to explain the antinociceptive effect of chronic imipramine treatment.Part of the paper was presented at the 17th International Congress of the International Society of Psychoneuroendocrinology, Bergen, June 29–July 4, 1986. 相似文献
88.
89.
Guus MJ Bökkerink Maja Joosten Erik Leijte Maud YA Lindeboom Ivo de Blaauw Sanne MBI Botden 《Journal of pediatric surgery》2021,56(3):465-470
BackgroundMinimal invasive surgery (MIS) is increasingly used for the correction of congenital diaphragmatic hernia (CDH) and esophageal atresia (EA). It is important to master these complex procedures, preferably preclinically, to avoid complications. The aim of this study was to validate recently developed models to train these MIS procedures preclinically.MethodsTwo low cost, reproducible models (one for CDH and one for EA) were validated during several pediatric surgical conferences and training sessions (January 2017–December 2018), used in either the LaparoscopyBoxx or EoSim simulator. Participants used one or both models and completed a questionnaire regarding their opinion on realism (face validity) and didactic value (content validity), rated on a five-point-Likert scale.ResultsOf all 60 participants enrolled, 44 evaluated the EA model. All items were evaluated as significantly better than neutral, with means ranging from 3.7 to 4.1 (p < 0.001). The CDH model was evaluated by 48 participants. All items scored significantly better than neutral (means 3.5–3.9, p < 0.001), with exception of the haptics of the simulated diaphragm (mean 3.3, p = 0.054). Both models were considered a potent training tool (means 3.9).ConclusionThese readily available and low budget models are considered a valid and potent training tool by both experts and target group participants.Type of studyProspective study.Level of evidenceLevel II. 相似文献
90.
María Jesús Fernández Aceñero MD PhD Cristina Díaz del Arco CDdA MD Carme Dinarés CD MD PhD Tania Labiano TL MD Eva Tejerina ET MD PhD Mª José Bernabé MJ B MD Elena Forcen EF MD Melchor Saiz-Pardo MSP MD Pablo Pérez PP MD Maria D. Lozano MDL MD PhD 《Diagnostic cytopathology》2023,51(1):26-35
Lung carcinoma remains one of the most frequent and aggressive human neoplasms. Fortunately, in the last decades, the increasing knowledge of the molecular mechanisms leading to cancer development has allowed the use of targeted therapies with improvement of prognosis in many patients. Clinical management has also changed after the introduction of endobronchialultrasonographic bronchoscopy that allows a conservative staging of lung tumors, avoiding the need of mediastinoscopy for lymph node staging. Lung pathologists and cytopathologists are facing the challenge of giving the more comprehensive prognostic and predictive information with ever smaller tissue or cytological samples. The aim of this review is to summarize the molecular testing for non-small cell lung carcinoma and how pathologists can contribute to the patient's outcome with a conscious management of biological samples. 相似文献