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41.
Felix Eckstein Beat Merz Magdalena Müller-Gerbl Nikolaus Holzknecht Markus Pleier Reinhard Putz 《Anatomical record (Hoboken, N.J. : 2007)》1995,243(3):327-335
Background: A deeper joint socket (concave incongruity) is found at most angles of flexion of the humero-ulnar joint and maintained over a wide range of physiological loading. It is, however, unclear how far this incongruity affects the distribution of load and subchondral mineralization of this joint as compared with a congruous configuration. Methods: Two nonlinear, axisymmetrical finite element models with two cartilage layers were constructed, one congruous and one incongruous, with a joint space of realistic magnitude. The distribution of subchondral mineralization was determined by computed tomography osteoabsorptiometry in the same six specimens that were investigated in the first part of the study, and compared with the biomechanical data obtained there and the predictions of the models. Results: In the congruous case, the center of the socket is highly loaded, whereas the periphery does not experience mechanical stimulation. A central bone density maximum is predicted. With concave incongruity the position of the contact areas shifts from the joint margin towards the center as the load increases, and the peak stresses are considerably lower. A bicentric ventro-dorsal distribution pattern of subchondral mineralization is predicted, and this is actually found in the six specimens. Conclusions: Concave incongruity is shown to determine load transmission and subchondral mineralization of the humero-ulnar joint. It is suggested that this shape leads to a more even distribution of stress, provides intermittent stimulation of the cartilaginous tissue, and has beneficial effects on the metabolism, nutrition, and lubrication of the articular cartilage during cyclic loading. © 1995 Wiley-Liss, Inc. 相似文献
42.
A. Marx J. P. Ruppersberg R. Rüdel 《Pflügers Archiv : European journal of physiology》1987,408(5):537-539
The membrane potential of Xenopus oocytes showed a variable response to an increase of the K+ concentration in the bathing solution, [K+]e, from 2.5 mM to 20 mM. In 54% of the cases (n=52) the cells hyperpolarized (by max. 70 mV). In the presence of 10–5 M ouabain, all cells depolarized suggesting that the hyperpolarization was caused by an electrogenic Na+/K+ pump. In cells stored overnight in a Na+-free solution the transition from 2.5 to 20 mM [K+]e always caused depolarization indicating that the stimulation of the pump requires high internal sodium, [Na+]i. Cells stored overnight in a Na+-rich solution had a [Na+]i of 30.7±7 mM, i.e. the Na+/K+ pump was saturated with sodium (Lafaire and Schwarz 1986). With 9 such cells we determined the K+ activation of the Na+/K+ pump. The activation follows Hill kinetics with Imax=90.5 nA, Ks=2.3 mM, and n=1.68. 相似文献
43.
P.M. Freedman Barbara Ault C.R. Zeiss M.W. Treuhaft R.C. Roberts D.A. Emanuel M.C. Baldauf J.J. Marx 《The Journal of allergy and clinical immunology》1981,67(1):51-58
Intradermal skin tests with a culture filtrate antigen of Micropolyspora faeni grown on a synthetic medium were performed on patients with farmers' lung disease (FLD) and well farmers with and without antibodies to a panel of FLD antigens. Seventy-five percent of the FLD patients, 79% of the well farmers with M. faeni antibody, and 5% of well farmers without M. faeni antibody had a 2+ or greater intradermal immediate skin-test reaction. Prausnitz-Küstner (P-K) reactions were positive using serum of M. faeni immediate skin test-positive FLD patients. IgG-rich fractions from a staphylococcal protein A-Sepharose column of such serum contained the sensitizing factor whereas IgG-depleted fractions did not. M. faeni—specific IgE could not be detected in serum by a polystyrene radioimmunoassay. Positive late-onset (6-hr) skin tests occurred only in FLD patients and farmers with precipitating antibody. Biopsy specimens of the 6-hr reactions revealed a generalized dermal and perivascular polymorphonuclear infiltrate with deposits of immunoglobulin and complement about blood vessels. The skin-sensitizing factor noted in FLD patients and well farmers with antibody is not disease specific. This factor appears to be associated with the IgG-rich fraction of serum, and its role in the pathogenesis of FLD is unclear. 相似文献
44.
Immunohistochemical studies have shown that almost all thymomas of myasthenia gravis (MG) patients contain proteins which share antigenic determinants with the nicotinic acetylcholine receptor (AChR) of human muscle. Here we describe one of the proteins (p153) which (1) is not part of a compound structure, (2) has a MW of 153 kd, (3) has an isoelectric point of 5.0, and (4) is probably free of sugar residues. The protein does not bind mAb to the main immunogenic region of the AChR and has no alpha-bungarotoxin (alpha-btx) binding site. p153 was not found in both normal tissues and a variety of tumours. However, the epitope defined by mAb155 also occurs in at least two other proteins (from muscle and TE671 cells) which have MW different from 153 kd and which are unrelated to AChR. Experiments presented elsewhere [Geuder et al., this volume] show that there are no proteins in thymomas which share an extensive molecular homology with the AChR. All these findings suggest that p153 is unrelated to the AChR. As p153 is the only protein demonstrated in thymomas which is significantly correlated with MG and which shares an antigenic determinant with AChR, p153 is a candidate protein determining the AChR-specificity of the autoimmune process in MG. 相似文献
45.
Natural history of endemic type D retrovirus infection and acquired immune deficiency syndrome in group-housed rhesus monkeys 总被引:5,自引:0,他引:5
N W Lerche P A Marx K G Osborn D H Maul L J Lowenstine M L Bleviss P Moody R V Henrickson M B Gardner 《Journal of the National Cancer Institute》1987,79(4):847-854
A 2.5-year epidemiologic study of a breeding group of rhesus monkeys (Macaca mulatta), which is a focus of endemic simian acquired immunodeficiency syndrome (SAIDS), demonstrated a strong association between the occurrence of SAIDS and infection with a type D retrovirus, SAIDS retrovirus serotype 1 (SRV-1). Of 23 healthy "tracer" juvenile rhesus monkeys, 19 (83%) died with SAIDS within 9 months of introduction into the resident SAIDS-endemic population. In contrast, 21 healthy "sentinel" juvenile rhesus monkeys placed in the same outdoor enclosure but denied physical contact with the SAIDS-affected group by a 10-foot-wide "buffer zone" remained free of SRV-1, SRV-1 antibody, and disease for 2.5 years. The SAIDS-specific mortality rate was significantly higher in juveniles than in adults. In repeated serologic testing, the overall prevalence of SRV-1 antibody ranged from 68 to 85%. Antibody prevalence increased with age. Seroconversion was found to be a poor indicator of infection rate, as approximately 50% of virus-positive juvenile monkeys had no antibody detectable by enzyme-linked immunosorbent assay. Repeated viral isolations from all animals revealed 1) SRV-1 viremia with clinical SAIDS; 2) persistent viremia and viral shedding in apparently healthy animals; 3) transient viremia and clinical recovery; 4) intermittent viremia, suggesting activation of latent infections; and 5) viremia in a 1-day-old infant, suggesting transplacental transmission. The prevalence of SRV-1 antibody in SAIDS-free breeding groups of rhesus monkeys was 4%. The seroprevalence of antibodies against human T-cell leukemia virus type 1 (HTLV-1), human immunodeficiency virus (HIV), and simian immunodeficiency virus (SIV; formerly STLV-III) was uniformly low or absent in both SAIDS-free and SAIDS-affected groups of rhesus monkeys, demonstrating that these retroviruses are not etiologically linked to SAIDS at the California Primate Research Center. 相似文献
46.
do Amaral Leandro Custódio Reis Baltazar Leão Ribeiro-Oliveira Antônio da Silva Santos Thamires Marx Giannetti Alexandre Varella 《Neurosurgical review》2021,44(3):1687-1702
Neurosurgical Review - A preferred treatment for residual/recurrent pituitary adenomas has not been established. The existence of higher complication rates for revision surgeries remains under... 相似文献
47.
Hanno Niess Nikolaus Börner Maximilian Muenchhoff Elham Khatamzas Manfred Stangl Alex Graf Philipp Girl Enrico Georgi Dionysios Koliogiannis Gerald Denk Michael Irlbeck Jens Werner Markus Guba 《American journal of transplantation》2021,21(4):1629-1632
To date, little is known about the duration and effectiveness of immunity as well as possible adverse late effects after an infection with SARS-CoV-2. Thus it is unclear, when and if liver transplantation can be safely offered to patients who suffered from COVID-19. Here, we report on a successful liver transplantation shortly after convalescence from COVID-19 with subsequent partial seroreversion as well as recurrence and prolonged shedding of viral RNA. 相似文献
48.
Tobias Veit Dieter Munker Jürgen Barton Katrin Milger Teresa Kauke Bruno Meiser Sebastian Michel Michael Zoller Hans Nitschko Oliver T. Keppler Jürgen Behr Nikolaus Kneidinger 《American journal of transplantation》2021,21(10):3449-3455
Letermovir is a new antiviral drug approved for the prophylaxis of CMV infection in allogeneic stem cell transplants. The aim of the study was to assess the therapeutic efficacy of letermovir in difficult to treat CMV infections in lung transplant recipients. All lung transplant recipients between March 2018 and August 2020, who have been treated with letermovir for ganciclovir-resistant or refractory CMV infection were included in the study and analysed retrospectively. In total, 28 patients were identified. CMV disease was present in 15 patients (53.6%). In 23 patients (82.1%), rapid response was noticed, and CMV-viral load could be significantly decreased (>1 log10) after a median of 17 [14–27] days and cleared subsequently in all of these patients. Five patients (17.9%) were classified as non-responder. Thereof, development of a mutation of the CMV UL56 terminase (UL-56-Gen: C325Y) conferring letermovir resistance could be observed in three patients (60%). Common side effects were mild and mostly of gastrointestinal nature. Mild adjustments of the immunosuppressive drugs were mandatory upon treatment initiation with letermovir. In addition to other interventions, letermovir was effective in difficult to treat CMV infections in lung transplant recipients. However, in patients with treatment failure mutation conferring letermovir, resistance should be taken into account. 相似文献
49.
Immunocytochemical characteristics of small cell lung carcinoma associated with the Lambert-Eaton myasthenic syndrome. 总被引:1,自引:0,他引:1 下载免费PDF全文
C. S. Morris M. M. Esiri A. Marx J. Newsom-Davis 《The American journal of pathology》1992,140(4):839-845
The Lambert-Eaton myasthenic syndrome (LEMS) is characterized by the presence of IgG antibodies to motor nerve terminals, and associates with small cell lung carcinoma in more than 60% of cases. We have carried out a comparative immunocytochemical study on small cell lung carcinoma (SCLC) in five LEMS cases and six non-LEMS cases, using antibodies to tumor markers, MHC Class I and II, macrophages and lymphocytes. The authors found a reduced expression of the 200Kd neurofilament antigen and of MHC Class I antigens in the LEMS cases as well as a greater infiltration of activated macrophages. It is suggested that these findings are consistent with the view that SCLC antigenic determinants trigger the autoantibody response in SCLC-LEMS. 相似文献
50.
This study examined the role of perceived token resistance and previous sexual contact on women's ability to discriminate when a female wants her partner to stop his sexual advances. Participants included 101 White female undergraduate students and were randomly assigned to one of the four conditions: 1) perceived resistance with genital contact; 2) no resistance with genital contact; 3) perceived resistance with no genital contact; and 4) no resistance without genital contact. Subjects listened to an audiotaped date rape after being informed of the couple's sexual history based on the condition assigned to them. They were also informed that the couple had been on five previous dates, in which the man had manipulated the woman's breasts or genitals. In addition, the woman did not object to this contact, or the woman initially objected to the contact but subsequently stopped resisting contact. Participants in the perceived token resistance conditions took significantly longer to determine when the man should refrain from attempting further sexual contact. The findings of this study could be used to increase information on date rape, to educate individuals about the responses associated with date rape, and to reinforce rules concerning appropriate sexual behavior. 相似文献