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51.
Köckerling F. Hantel E. Adolf D. Kuthe A. Lorenz R. Niebuhr H. Stechemesser B. Marusch F. 《Hernia》2021,25(5):1169-1181
Hernia - There are hardly any studies on the outcome of scrotal compared with medial and lateral inguinal hernias. Therefore, this present multivariable analysis of data from the Herniamed Registry... 相似文献
52.
Clephane Kirstin Sartin-Tarm Anneliis Lorenz Tierney K. 《Archives of sexual behavior》2022,51(2):737-742
Archives of Sexual Behavior - 相似文献
53.
Ohne Zusammenfassung 相似文献
54.
55.
Dr. med. W. U. Schmidt J. Sattler R. Hesterberg H. D. Röher Th. Zoedler H. Sitter W. Lorenz 《Inflammation research》1990,30(1-2):267-270
The key-enzyme for the metabolism of diamines in man is diamine oxidase (DAO). Its highest activities are in the intestinal mucosa, localized in the cytoplasm of the mature enterocytes of the small and large bowel. If the gut is affected by inflammation in Crohn's disease macroscopical changes are observed. This prospective study investigated if these mucosal alterations are also reflected in changes of mucosal diamine oxidase activity and/or mucosal histamine content respectively. Twenty patients (12 female, 8 male; age:
, range 18 49 years) undergoing gut resection because of complications in Crohn's disease (Jan.–Dec. 1988) formed the basis of the study. Tissue samples of the resected material from areas inflamed and histologically not involved in the disease were investigated for diamine oxidase activities and histamine content. Diamine oxidase activities in the mucosa obtained from the macroscopically normal proximal (155.6; (76–393) mU/g (
range)) and distal (132; (58.5–295) mU/g) resection margins were similar to our previous findings. In all patients, however, samples from the diseased mucosa had significantly (ca. 50%) lower diamine oxidase activities (74.5; (5–262) mU/g) compared to the healthy tissue. Similar differences were found in material obtained either from whole intestinal wall or from the mucosa. The determination of diamine oxidase activity constitutes possibly a more unambiguous and earlier parameter for assessing the extent of the inflamed area than histological disease presentations. Using biopsies the necessary extent of resection could be estimatedbefore operation: this may influence operative strategies and help in the definition of the minimum amount of inflamed gut to be removed.Supported by grant of Deutsche Forschungsgemeinschaft (Lo 199/15-2). 相似文献
56.
Expression of three alpha 2-adrenergic receptor subtypes in rat tissues: implications for alpha 2 receptor classification 总被引:11,自引:0,他引:11
W Lorenz J W Lomasney S Collins J W Regan M G Caron R J Lefkowitz 《Molecular pharmacology》1990,38(5):599-603
Based on biochemical and ligand binding studies in various tissues and species, evidence for several alpha 2-adrenergic receptor subtypes has accumulated. The current alpha 2-adrenergic receptor classification (alpha 2A, alpha 2B, alpha 2C) is based exclusively on pharmacological criteria. The molecular cloning of three distinct genes for human alpha 2-adrenergic receptors has confirmed the existence of multiple alpha 2-adrenergic receptor subtypes. According to their localization on different human chromosomes, the receptor genes were termed alpha 2-C10, alpha 2-C4, and alpha 2-C2. The relationship, however, between the pharmacologically characterized alpha 2-adrenergic receptors and the isolated genes has yet to be clarified. Using Northern blot hybridization, we analyzed the expression of the three cloned alpha 2-adrenergic receptor genes in 13 rat tissues, as well as in cell lines previously described as model systems for the pharmacologically defined alpha 2-adrenergic receptor subtypes. The alpha 2-C10 receptor corresponds to the alpha 2A subtype and is expressed in rat brainstem, cerebral cortex, hippocampus, pituitary gland, cerebellum, kidney, aorta, skeletal muscle, spleen, and lung. Messenger RNA coding for the alpha 2-C4 receptor was detected only in brain regions, not in peripheral tissues, whereas the alpha 2-C2 message was found only in liver and kidney. Hybridization experiments with RNA derived from tissues and cells from which the pharmacological alpha 2-receptor classification has been developed lead to the conclusion that the alpha 2B subtype represents two distinct receptor molecules, the alpha 2-C4 and a subtype previously undetected by classical ligand binding approaches. Furthermore, our results suggest that the alpha 2C subtype characterized in opossum kidney cells is an interspecies variation of alpha 2-C4 rather than a separate subtype. Finally, the cloned alpha 2-C2 receptor was found to be "alpha 2B-like" and not covered by the current pharmacological classification. 相似文献
57.
Justin Leube Anton Mühlbauer Immanuel Andrä Madleen Biggel Dirk H. Busch Lorenz Kretschmer Veit R. Buchholz 《European journal of immunology》2023,53(3):2250009
T cell ignorance is a specific form of immunological tolerance. It describes the maintenance of naivety in antigen-specific T cells in vivo despite the presence of their target antigen. It is thought to mainly play a role during the steady state, when self-antigens are presented in absence of costimulatory signals and at low density or to T cells of low affinity. In how far antigen-specific T cells can also remain clonally ignorant to foreign antigens, presented in the inflammatory context of systemic infection, remains unclear. Using single-cell in vivo fate mapping and high throughput flow cytometric enrichment, we find that high-affinity antigen-specific CD8+ T cells are efficiently recruited upon systemic infection. In contrast, most low-affinity antigen-specific T cells ignore the priming antigen and persist in the naïve state while remaining fully responsive to subsequent immunization with a high-affinity ligand. These data establish the widespread clonal ignorance of low-affinity T cells as a major factor shaping the composition of antigen-specific CD8+ T cell responses to systemic infection. 相似文献
58.
M. Koller H. Kienapfel D. Hinder E. Sabau G. Wingert M. Pfeiffer P. Griss W. Lorenz 《Der Chirurg》1999,70(11):1364-1373
A scale for measuring symptoms related to degenerative diseases of the cervical spine is presented. Twenty typical symptoms are listed, e. g., neck pain, dysesthesia, and reduced mobility. Responses are assessed via a 6-point scaling ("did not have symptom" - "had symptom and suffered very strongly".) The cervical spine scale was tested in three samples: patients having undergone cervical spine surgery (n = 70), patients with other orthopedic diagnoses (n = 104), and healthy students (n = 100). The single items of the scale were aggregated into four scores: total number of symptoms, degree of overall symptom distress, functional disability, and pain/psychological distress. Statistical analyses proved the high reliability (Cronbach's alpha = 0.85 to 0.95) and validity (content, convergent, discriminant) of all scores. The scale differs clearly between cervical spine patients, other orthopedic patients and healthy individuals, and between cervical spine patients with different subjective operative outcomes. For applied clinical purposes the cervical spine scale can be included in a quality of life profile (QL-profile); this allows for a readily understandable graphic depiction of individual patients' QL-status. 相似文献
59.
Contrast agents have dramatically improved magnetic resonance angiography (MRA) of the abdominal and peripheral arteries. The imaging technique for these applications is usually a steady-state acquisition, for which the relationship between T1 in blood and the MR signal is well known. However, in electrocardiography-triggered angiography with limited acquisition windows, this relationship is more complex. Therefore the purpose of this work is to define the relationship between the T1 in blood and the MR signal amplitude in three-dimensional magnetic resonance coronary angiography (3D-MRCA). Simulations were performed using equations describing the MR signal in both steady-state and triggered acquisition schemes. Triggered acquisition schemes use flip-angle sweeps to maintain a constant signal during the acquisition. In this study, the effect of the flip angle sweep was calculated as a function of T1. The results show that the effect of T1 shortening in contrast-enhanced 3D-MRCA differs substantially from that in conventional contrast-enhanced MRA. The triggered acquisition allows unsaturated blood to enter the volume between the acquisitions and thereby gives a much higher signal at long T1s than does steady-state acquisition. Therefore, to gain a benefit in signal amplitude with contrast agents for 3D-MRCA using gradient-echo sequences, the T1 in blood may have to be as low as 50 msec. In addition, when using a prepulse to null myocardium, the results indicate the need for a large difference in T1 between blood and myocardium to avoid signal loss in blood. 相似文献
60.
PURPOSE: The aim of this study was to determine the important factors in the development and subsequent treatment of postoperative paraesophageal hernia (PPEH). METHODS: A retrospective analysis was performed in 464 consecutive children (ages 3 days to 18 years) for PPEH after a primary antireflux operation performed at a Children's Hospital and University Hospital between 1985 and 1997. All operations included a crural repair, but the Nissen fundoplication was performed with (n = 162) and without (n = 70) plication of the esophagus to the crus at 3 points. Patients with and without PPEH were compared with respect to the type of antireflux operation, the patient's age at operation, and the preoperative and postoperative clinical courses. A preoperative corrected gastric emptying value was obtained from a radionuclide gastric emptying study in 289 patients. The treatment of PPEH also was examined. RESULTS: The incidence of PPEH in our patients was 4.5% (21 of 464). Although there was a lower incidence of PPEH in patients with crural plication compared with patients without crural plication during Nissen fundoplication (5 of 162, 3% v 7 of 70, 10%; P = .035), 2 patients with crural plication had a postoperative esophageal leak. Patients with PPEH had a significantly increased prevalence of gagging before the initial antireflux operation compared with patients without PPEH (3 of 21, 14.3% v 7 of 443, 1.6%; P = .007). A higher prevalence of slow corrected gastric emptying preoperatively also was seen in patients with PPEH compared with patients without PPEH (8 of 15, 53% v 79 of 274, 29%; P = .046). The prevalences of central nervous system disease, young age (<6 months) at initial operation, and a particular type of antireflux operation were not higher in patients with PPEH. Nine patients with a small PPEH treated by simple observation alone subsequently had resolution of symptoms. CONCLUSIONS: Patients who have gagging or slow corrected gastric emptying before an antireflux operation are at higher risk for a postoperative paraesophageal hernia. Patients with a small postoperative paraesophageal hernia can be treated nonoperatively. Crural plication of the esophagus during Nissen fundoplication reduces the occurrence of postoperative paraesophageal hernia, but also may result in significant morbidity. 相似文献