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排序方式: 共有685条查询结果,搜索用时 15 毫秒
1.
Robert N. Page Lee Dittrich Roy King Fouad Boulos David L. Page 《Journal of cutaneous pathology》2009,36(11):1206-1209
Originally described by Rosen in 1983, syringomatous nipple adenoma (SAN) is a tumor of disputed histogenesis, which can be problematic both diagnostically and therapeutically. 1 It is a benign primary tumor of breast epithelium with histology similar to that of the syringoma. In the current case, we describe a 40-year-old female with this lesion occurring within a supernumerary breast. This case represents, to our knowledge, the first such reported case, and represents a significant finding as its presence could lend some confusion as to whether or not this represents a benign primary process of breast or a potentially infiltrative tumor of the skin. 相似文献
2.
Role of collagenase in colonic anastomoses: a reappraisal 总被引:7,自引:0,他引:7
Increased collagenolysis, with reduction in collagen concentration, has been incriminated in the breakdown of colonic anastomoses but previous studies have measured only collagen levels and non-specific collagenolytic activity. Collagenase, the initiating enzyme in collagen degradation, is synthesized on demand and controlled by tissue inhibitor of metalloproteinases (TIMP). Antibodies to collagenase and TIMP were applied to colonic anastomoses in rabbits to investigate the role of the enzyme during healing. Within 12 h of operation, secreting cells and extracellular collagenase were identified at the everted edges of the bowel wall. After 24 h, collagenase activity was accompanied by TIMP secretion in the same localized regions, and by the third postoperative day very few cells were still synthesizing enzyme in these areas, although extracellular activity remained visible. TIMP-secreting cells, however, were seen in a layer of connective tissue sealing the serosal surface of the anastomosis. At 7 days, both enzyme and inhibitor were found only in small aggregates of secreting cells in the deeper layers. The localization and extent of collagenase and TIMP activity accorded well with a normal healing response as, at all times, the enzyme was confined to the immediate vicinity of the suture line. 相似文献
3.
4.
Feeding and drinking rhythms were studied in rats maintained under 24-hr light-dark (LD) cycles with various photoperiods, under two-pulse (2P) and one-pulse (1P) skeleton photoperiods, and under constant dark (DD). Rhythmic waveforms were similar under complete LD cycles and corresponding skeleton photoperiods, indicating that these rhythms mainly reflect the entrainment of underlying circadian pacemakers. Little or no role was found for masking effects of light on circadian feeding and drinking waveforms. Entrainment was found to depend mainly on the timing of the dawn light signal, whether it was a 15-min light pulse or a dark-to-light transition initiating a complete photoperiod. Furthermore, the use of 1P schedules revealed that a dawn signal was sufficient for entrainment. These results closely match those obtained for motor activity measures in other nocturnal rodent species, and generally conform to the predictions of Pittendrigh's nonparametric theory of entrainment. Furthermore, the close correspondence of the two rhythms during entrainment, phase-jumps, and free-running (DD) conditions indicates that they are controlled by common circadian pacemakers. 相似文献
5.
Shah P. M. Boulos P. B. Springall R. Vashisht R. Pearce F. L. 《Inflammation research》1994,41(1):C51-C52
The H2-antagonists famotidine and nizatidine produced a dose-dependent inhibition of histamine release from human colonic mucosal and muscle mast cells stimulated with anti-IgE. The IC30 values were in the range 0.5–10 μM and the maximum inhibition approached 50%. The compounds showed similar efficacy against rat peritoneal mast cells but were more potent. The cytoprotectant misoprostol had a striking effect on the human colonic mast cells, producing more than 50% inhibition at concentrations of 0.1–1 nM, but was much less active against the rat cells.
相似文献6.
Nicole Fakhoury Sayegh Gessica N. H. A. Heraoui Hassan Younes Lea Nicole Sayegh Christa Boulos Raymond Sayegh 《Nutrients》2022,14(12)
Non-alcoholic fatty liver disease (NAFLD) is considered the most common liver injury worldwide. NAFLD can evolve into non-alcoholic steatohepatitis (NASH) with or without fibrosis. The objectives of this study were to determine the nutritional profile and dietary patterns of NAFLD Lebanese patients and to report the type of diet-related to the presence of hepatic fibrosis. We hypothesized that the traditional pattern was related to a low risk of fibrosis. This cross-sectional study included 320 eligible Lebanese NAFLD patients. Three dietary patterns were identified: the Traditional diet, the High Fruit diet, and the Westernized diet. Multivariate analysis showed a significant relationship between high adherence to the traditional diet and absence of hepatic fibrosis with a decreased risk of 82%, p = 0.031 after adjusting for its covariables. Fruits were absent from this dietary pattern. Although our results pointed to a possible relationship between fibrosis in NAFLD patients and fruit intake, experimental studies are needed to show whether this is a causal relationship. However, the results obtained in this study may contribute to the planning of dietary interventions and recommendations and enable a better follow-up for NAFLD patients with fibrosis. 相似文献
7.
8.
Neuronal traits of clonal cell lines derived by fusion of dorsal root ganglia neurons with neuroblastoma cells. 总被引:8,自引:2,他引:8 下载免费PDF全文
D Platika M H Boulos L Baizer M C Fishman 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(10):3499-3503
In an attempt to immortalize the gene products of single neurons, somatic cell hybrids were produced by fusion of embryonic rat dorsal root ganglion (DRG) neurons with mouse neuroblastoma cells. Embryonic day 13 rat DRGs were fused with mouse neuroblastoma cells deficient in hypoxanthine phosphoribosyltransferase (HPRT; IMP:pyrophosphate phosphoribosyltransferase, EC 2.4.2.8). The hybrid cells were selected in medium with 100 microM hypoxanthine/1 microM aminopterin/12 microM thymidine to eliminate the neuroblastoma cells and with cis-hydroxyproline to retard fibroblast growth. Of the 17 lines derived, 4 manifested neuronal properties and were cloned. These lines retain both rat and mouse chromosomes and synthesize characteristic rat and mouse isoenzymes. Neuronal gangliosides, action potentials, and extensive neurite-like processes are exhibited by these hybrid cells, properties characteristic of DRG neurons but not of the neuroblastoma parent. Each line manifests a unique combination of action-potential properties and cell-surface markers, suggesting the selective expression of subsets of DRG neuronal genes. All of these neuronal properties are expressed constitutively, without the need for chemical induction or mitotic inhibition, and stably, without diminution after at least 5 months in culture. These lines may prove useful in the identification and isolation of gene products that characterize individual or small subsets of DRG neurons. 相似文献
9.
Diyar Falay Ehrenfried Schindler Marian Mikus Boulos Asfour Sylvia Schroth Alina Schenk Torsten Baehner 《Paediatric anaesthesia》2023,33(3):219-228
Aims
Central venous catheters are essential for the management of pediatric cardiac surgery patients. Recently, an ultrasound-guided access via a supraclavicular approach to the brachiocephalic vein has been described. Central venous catheters are associated with a relevant number of complications in pediatric patients. In this study, we evaluated the frequency of complications of left brachiocephalic vein access compared with right internal jugular vein standard access in children undergoing cardiac surgery.Methods
Retrospective analysis of all pediatric cases at our tertiary care university hospital over a two-year period receiving central venous catheters for cardiac surgery. Primary endpoint: Frequency of complications associated with central venous catheters inserted via the left brachiocephalic vein vs. right internal jugular vein. Complications were defined as: chylothorax, deep vein thrombosis, sepsis, or delayed chest closure. Secondary endpoints: Evaluation of the insertion depth of the catheter using a height-based formula without adjustment for side used.Results
Initially, 504 placed catheters were identified. Following inclusion and exclusion criteria, 480 placed catheters remained for final analysis. Overall complications were reported in 68/480 (14.2%) cases. There was no difference in the frequency of all complications in the left brachiocephalic vein vs. the right internal jugular vein group (15.49% vs. 13.65%; OR = 1.16 [0.64; 2.07]), nor was there any difference considering the most relevant complications chylothorax (7.7% vs. 8.6%; OR = 0.89 [0.39; 1.91]) and thrombosis (5.6% vs. 4.5%; OR = 1.28 [0.46; 3.31]). The mean deviation from the optimal insertion depth was left brachiocephalic vein vs. right internal jugular vein 5.38 ± 13.6 mm and 4.94 ± 15.1 mm, respectively.Conclusions
Among children undergoing cardiac surgery, there is no significant difference between the supraclavicular approach to the left brachiocephalic vein and the right internal jugular vein regarding complications. For both approaches, a universal formula can be used to determine the correct insertion depth. 相似文献10.
Toursarkissian B Shireman PK Harrison A D'Ayala M Schoolfield J Sykes MT 《The American surgeon》2002,68(7):606-610
Our objective is to describe our current experience with major lower-extremity amputation secondary to vascular disease. We conducted a retrospective review of sequential amputations over a 3-year period at one Veterans Affairs institution. One hundred thirteen amputations were performed in 99 men (age 70 +/- 11 years). Seventy-five per cent were diabetic and 23 per cent were on dialysis. Fifty-six per cent were primary amputations. The final AKA/BKA (above-knee to below-knee amputation) ratio was 3:2 and was not related to prior bypass, ethnicity, or dialysis status (P > 0.5). Forty-three per cent of amputations were BKAs in diabetics versus 26 per cent in nondiabetics (P = 0.08). The in-hospital and 30-day mortality rates were 2.6 and 8 per cent and were not related to amputation level (P = 0.76). Forty per cent experienced postoperative complications that were most frequently wound related (22%). Wound complications were more frequent with BKA than AKA (P = 0.04). At an average follow-up of 10 +/- 8 months only 65 per cent were alive. Although 51 per cent were discharged to rehabilitation units only 26 per cent regularly wore a prosthesis with 23 per cent ambulating. BKA patients were more likely to ambulate than AKA (34% vs 9%; P = 0.001), and dialysis patients were less likely to ambulate than nondialysis patients (5% vs 25%; P < 0.02). During follow-up 17 per cent of patients discharged with an intact contralateral limb required amputation of that limb and 7 per cent had bypass surgery on that limb. Complication rates were higher in African Americans and Hispanics than in whites (59%, 45%, and 23%, respectively; P < 0.001), although mortality and ambulation rates were similar. Despite an acceptable perioperative mortality complication rates remain high especially in nonwhites. One-year mortality is high. Low rehabilitation rates especially in dialysis patients mandate further efforts in this regard. Vigilant follow-up of the contralateral limb is essential. 相似文献