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排序方式: 共有1103条查询结果,搜索用时 15 毫秒
121.
T Jansen D Regele CG Schirren B Trautner G Plewig 《Canadian Metallurgical Quarterly》1998,49(12):932-935
A 24-year-old woman with lymph vessel dysplasia had experienced a progressive edema of her legs since her second year of life and progressive facial edema for the past year. She also had telangiectasias and papules on the background of a diffuse erythema as well as marked seborrhea on her face. Histopathological examination of a representative facial lesion revealed a granulomatous dermatitis with periadnexal distribution mainly consisting of lymphocytes and histiocytes. In addition, there was a moderate fibrosis of the dermis with numerous mast cells. By duplex ultrasound, a diagnosis of a massive edema of the legs without evidence for chronic venous insufficiency was made. The clinical and histopathological findings were consistent with solid persistent erythema and edema of the face associated with rosacea and lymph vessel dysplasia. The chronic course, absence of serological abnormalities and nonspecific histopathological features as well as resistance to therapy are the most important diagnostic criteria of this disease also known as Morbihan's disease. 相似文献
122.
It is well documented that IL-6 plays a critical role in B cell terminal differentiation, and in mucosal sites it stimulates proliferation and large-scale secretion of immunoglobulin by B cells, especially those committed to IgA production. The close juxtaposition of IL-6 mRNA+ cells to plasma cells in the intestinal lamina propria supports the proposition that IL-6 production in situ is an important factor determining the outcome of antibody responses at that site. However, it has not been established previously whether exogenous IL-6 could boost antibody responses in the intestine if administered with a challenge antigen. Using a resected gut loop (Thiry-Vella loop) model, we have been able to demonstrate that in mice with double loops, antibody containing cell responses to lumenal administration of ovalbumin were 50% greater in loops given intralumenal recombinant IL-6 with the challenge antigen, than in loops challenged with antigen alone. This demonstrates the efficacy of IL-6 in promoting accumulation of antibody secreting cells in the gut, and suggests a potential therapeutic role for IL-6 to enhance responses to mucosal vaccines. 相似文献
123.
R Plate MJ Plaum P Pintar CG Jans T de Boer FA Dijcks G Ruigt JS Andrews 《Canadian Metallurgical Quarterly》1998,6(9):1404-1420
A series of 1,6-dihydro-5-(4H)-pyrimidinone oxime derivatives I was synthesized (Scheme 1, Tables 1 and 2) and tested for muscarinic activity (Table 3) in receptor binding assays using [3H]-oxotremorine-M (Oxo-M) and [3H]-pirenzepine (Pz) as ligands. Potential muscarinic agonistic or antagonistic properties of the compounds were determined using binding studies that measured their potencies to inhibit the binding of Oxo-M and Pz. Preferential inhibition of Oxo-M binding was used as an indicator for potential muscarinic agonistic properties; this potential was confirmed in functional studies on isolated organs. The series produced a wide range of active compounds with differing degrees of selectivity in M1, M2, and M3 functional models. Several compounds that have mixed agonist/antagonist profiles were able to reduce cholinergic-related cognitive impairments in models of mnemonic function. Substitutions (I, e.g. R2 or R3 = Me) at the 1,6-dihydro-5-(4H)pyrimidine ring disrupted binding and efficacy, whereas systematic variation of the oximes substituent R1 resulted in various degrees of potency and selectivity dependent on the nature of the substitution. 相似文献
124.
Survivorship analysis of the Kinematic Stabilizer total knee replacement: a 10- to 14-year follow-up
The Kinematic Stabilizer is a posterior-cruciate-substituting design of total knee replacement. We have reviewed 109 primary total knee replacements in 95 patients at a mean follow-up time of 12.7 years (10 to 14). We used survival analysis with failure defined as revision of the implant. This gave a cumulative survival rate of 95% (95% CI +/- 5%) at ten years and (87% +/- 10%) at 13 years. These results from an independent centre confirm the value of an established design of cemented total knee replacement and question the wisdom of the introduction of modifications and new designs without properly controlled trials. 相似文献
125.
The high-pressure Diels-Alder reaction of N-carbomethyoxypyrroles and phenyl vinyl sulfone affords versatile intermediates for the palladium-catalyzed preparation of new epibatidine analogues. Structure-activity relationships of new epibatidine analogues are presented. High affinities of Ki = 0.81 and 2.6 nM for the [3H]-cytisine rat brain nicotinic acetylcholine binding sites were found for the 5-pyrimidinyl and the 5-(2-amino)-pyrimidinyl epibatidine analogues, respectively. 相似文献
126.
DJ Ruiter PH de Mulder JA Schalken CG Figdor 《Canadian Metallurgical Quarterly》1995,139(44):2240-2246
127.
J Heimbucher KH Fuchs SM Freys GW Clark R Incarbone TR DeMeester CG Bremner A Thiede 《Canadian Metallurgical Quarterly》1994,168(6):622-5; discussion 625-6
PURPOSE: The aim of this study was to evaluate motility patterns of the Hunt-Lawrence pouch and the jejunal limb of patients reconstructed with a pouch after total gastrectomy, and to compare the findings in symptomatic patients to those without symptoms after the operation. PATIENTS AND METHODS: Thirty-three patients who had undergone post-gastrectomy pouch reconstruction were studied using a water-perfused motility system. In 21, the pouch was connected by a Roux-en-Y, and, in 12, by a jejunal interposition. Twenty-eight patients were asymptomatic, including 17 connected by a Roux-en-Y and 11 by a jejunal interposition. Five patients were by a jejunal interposition. Five patients were symptomatic, including 4 connected by Roux-en-Y Y and 1 by jejunal interposition. A control group consisted of 5 healthy volunteers who had not undergone operation. RESULTS: The motility phases in the pouch and jejunal limb of asymptomatic patients were of shorter duration than those of controls, and they followed a random sequence instead of a normal progression from phase I to II to III. Motility features were similar in the pouch and the jejunal limb. Orthograde propagation of phase III-like activity was reduced and may contribute to the pouch storage function. Four of the 5 symptomatic patients showed highly abnormal motility with hypomotile or obstructive patterns. The technique of connecting the pouch--jejunal interposition of Roux-en-Y--did not affect the motility findings. CONCLUSIONS: The altered motility occurs after a Hunt-Lawrence pouch reconstruction in asymptomatic patients. Symptoms after gastrectomy are associated with further disturbed motility that can be differentiated from the motility changes in asymptomatic patients. 相似文献
128.
The critical role that the meniscus plays in the knee along with the advantages of preserving as much of the meniscus as possible have both been well documented. Whenever possible, meniscus repair has become the procedure of choice for treatment of meniscal tears. However, some researchers have reported less favorable results in older patients. To determine the results of meniscus repair in older patients, patients 40 years and older who underwent arthroscopically assisted meniscus repair were prospectively followed up. Thirty-seven patients were included in the study, all of which had a minimum 2-year follow-up (average, 26.5 months). The average age of the patients at the time of the repair was 44.2 years (range, 40 to 52 years); 26 were males and 11 were females. There were 19 left knees and 18 right knees included in the study. Twenty-two patients had associated anterior cruciate ligament reconstructions. Physical examination at follow-up included swelling, joint line tenderness, locking, and McMurray testing and radiographs. Five of 37 menisci repaired (13.5%) were symptomatic at latest follow-up. All of these patients had joint line tenderness and two had a positive McMurray test. Three of these patients had repeat arthroscopy confirming that the meniscus had not healed. Because of the small number of patients with symptoms at follow-up, the authors feel that meniscus repair in patients 40 years and older is an effective treatment for peripherally located meniscus tears. With 86.5% of the patients having good clinical results, these findings are comparable with other studies with a younger population and signify that repair of peripheral tears is indicated in this age group especially in conjunction with anterior cruciate ligament reconstruction. The findings suggest that the location and meniscal tear, rather than the age of the patient, determine the potential for successful repair. 相似文献
129.
RC King VE Laubach RC Kanithanon AM Kron PE Parrino KS Shockey CG Tribble IL Kron 《Canadian Metallurgical Quarterly》1998,66(5):1732-1738
BACKGROUND: Cyclic guanosine monophosphate (cGMP) is a potent second messenger for the nitric oxide pathway in the pulmonary vasculature. Increased cytosolic cGMP levels elicit pulmonary vasodilatation resulting in decreased pulmonary vascular resistance and maximized pulmonary function after ischemia-reperfusion injury. We hypothesized that the addition of a membrane-permeable cGMP analogue (8-bromo-cGMP) to a Euro-Collins (EC) preservation solution would ameliorate pulmonary reperfusion injury better than prostaglandin E1 injection alone after prolonged hypothermic ischemia. METHODS: All lungs from New Zealand White rabbits (weight, 3 to 3.5 kg) were harvested en bloc, flushed with EC solution, and reperfused with whole blood for 30 minutes. Group 1 lungs (immediate control) were immediately reperfused. Group 2 lungs (control) were stored inflated at 4 degrees C for 18 hours before reperfusion. Groups 3 and 4 lungs were flushed with EC solution containing 200 micromol/L 8-bromo-cGMP and stored at 4 degrees C for 18 and 30 hours, respectively. Fresh, nonrecirculated venous blood was used to determine single-pass pulmonary venous-arterial oxygen gradients at 10-minute intervals. Assays for cGMP, cyclic adenosine monophosphate, nitric oxide synthase activity, and myeloperoxidase were performed on all lung tissue samples. Wet to dry weight ratios were determined after 2 weeks of passive desiccation. RESULTS: Oxygenation (venous-arterial oxygen gradient), pulmonary artery pressure, pulmonary vascular resistance, and edema formation were significantly improved in groups 3 and 4 (addition of 8-bromo-cGMP to EC plus 18 or 30 hours of hypothermic ischemia). Hypothermic storage (groups 2, 3, and 4) decreased both nitric oxide synthase activity and myeloperoxidase levels compared with immediate reperfusion (group 1). CONCLUSIONS: These results suggest that the addition of a membrane-permeable cGMP analogue to an EC pulmonary flush solution improves pulmonary function after prolonged storage compared with EC and prostaglandin (E1) preservation alone. The finding of myeloperoxidase reduced levels after hypothermic storage and subsequent reperfusion may suggest a more important role for pulmonary hemodynamic control in mitigating pulmonary reperfusion injury. 相似文献
130.
A process for preparing zinc alloy castings containing dispersions of zircon particles is described. Composites were prepared
by stirring zircon particles in Zn-4Al-3Cu (ZAS) alloy melts and subsequently casting these melts in permanent molds. It was
found that additions of zircon resulted in an increase in the sliding wear resistance and in the proportional limit in compression.
The aging characteristics of the ZAS alloy have also been investigated by hardness tests, dilatometry technique, and transmission
electron microscopy observations. There are two kinds of precipitates that occur during the aging process. The α-phase precipitates
from the ŋ phase in the early stage of aging and the copper-rich ɛ-phase precipitates from the ŋ phase in the later stage
of aging. Therefore, there are two peaks in the hardening curve caused by both a-phase and ŋ-phase precipitation. The a-phase
precipitation induces the dimensional shrinkage, and the copper-rich ŋ phase precipitation results in dimensional expansion.
Zircon particles existing in ZAS alloy reduce the maximum shrinkage from 353 × 10-6 for the monolith to 167 × 10-6 for the composite. Two groups of parallel a-phase plates had formed within the ŋ dendrite during aging at 95 °. The orientation
relationship between the a phase and matrix was determined as [άcr1l01]ŋ//[lάrc10]a, (1120)ŋ/(lll)α. 相似文献