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31.
Studies of the ontogeny of IGF-I mRNA during embryonic and larval development of the gilthead sea breamSparus auratashowed its expression during these early developmental stages. The present study appliesin situhybridization to localize IGF-I and IGF receptor mRNAs in 16-day larvae ofS. aurata.Paraffin sections were hybridized with homologous RNA probes labeled by [35S]UTP. IGF-I mRNA expression was found mainly in chondrocytes, in both the gill arches and cranial cartilage, in skeletal muscle, in the brain, in the pancreas, in the retina, and in the epithelial cells surrounding the lens. A strong positive reaction for IGF receptor mRNA was found in skeletal muscle, in the pancreas, and in the lymphoid tissue found in the intertubular tissue of the kidney. Signals were less intense in brain and chondrocytes. It is suggested that in teleosts, as in higher vertebrates, IGF-I may be involved in the regulation of tissue growth and differentiation in an autocrine/paracrine manner. 相似文献
32.
In a period of 2 years 7 months, we performed heat probe (HP) thermocoagulation in 153 cases of massive peptic ulcer hemorrhage. The male/female sex ratio was 125/28. The average age was 57.6 +/- 1.3 years (mean +/- SEM; range, 17 to 88). There were 69 cases (45.1%) of spurting hemorrhage, 50 cases (32.7%) of oozing hemorrhage, and 34 cases (22.2%) of nonbleeding visible vessels. Seventy-seven patients (50.3%) were in shock before therapy. After therapy we obtained initial success in 147 cases (96.1%). Rebleeding episodes occurred in 23 patients (15.6%) within 1 month after therapy. Nineteen patients received a second therapy, and treatment in 15 of these cases (78.9%) was ultimately successful. Finally, treatment in 142 cases (92.8%) was ultimately successful. The duration of hospitalization was 6.3 +/- 0.4 days (mean +/- SEM). After discharge all patients were followed at the outpatient department for at least 1 month. Sixty-seven patients were followed endoscopically for at least 2 to 3 months after therapy. Fifty-six patients (83.6%) had a healed scar at the previous bleeding site 2 months after therapy, and 62 patients (92.5%) had a healed scar 3 months after therapy. We conclude that HP thermocoagulation is an ideal and reliable modality of therapeutic endoscopy in arrest of massive peptic ulcer hemorrhage. HP thermocoagulation may become the first choice of therapy for massive peptic ulcer bleeding in the near future. 相似文献
33.
34.
P. P. Fleming A. K. Chan M. G. O’Brien G. C. O’Sullivan M.Ch. FRCSI 《Irish journal of medical science》1997,166(1):13-15
Laparoscopic appendicectomy has been the subject of several encouraging reports, but has not as yet gained widespread acceptance. We present a series of 159 consecutive laparoscopic appendicectomies performed, over a 4 yr period, in both adults and children. We find the procedure as safe as its open counterpart, with patients fit to leave hospital within the same time period. Perforated appendices were amenable to this procedure, and the location of the appendix did not alter the outcome. Children responded as well as adults post-operatively. Obesity may be an indication for this form of treatment. Removal of displaced faecoliths associated with perforated appendicitis is a difficult technical problem in less than 5 per cent of patients. 相似文献
35.
Stimulation of protein phosphatase activity by insulin and growth factors in 3T3 cells. 总被引:9,自引:1,他引:8 下载免费PDF全文
C P Chan S J McNall E G Krebs E H Fischer 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(17):6257-6261
Incubation of Swiss mouse 3T3-D1 cells with physiological concentrations of insulin resulted in a rapid and transient activation of protein phosphatase activity as measured by using [32P]phosphorylase a as substrate. Activation reached a maximum level (140% of control value) within 5 min of addition and returned to control levels within 20 min. The effect of insulin was dose-dependent with half-maximal activation occurring at approximately 5 nM insulin. This activity could be completely inhibited by addition of the heat-stable protein inhibitor 2, which suggests the presence of an activated type-1 phosphatase. Similar effects on phosphatase activity were seen when epidermal growth factor and platelet-derived growth factor were tested. These results suggest that some of the intracellular effects caused by insulin and growth factors are mediated through the activation of a protein phosphatase. 相似文献
36.
Perry Guaglianone Kenneth Chan Eduardo DelaFlor-Weiss Rosemarie Hanisch Susan Jeffers Desh Sharma Franco Muggia 《Investigational new drugs》1994,12(2):103-110
Summary We have completed a phase I and pharmacology study of liposomally-encapsulated daunorubicin (DaunoXome). Of 32 patients entered, 30 were evaluable. No toxicity was encountered at the initial doseescalation steps from 10 to 60 mg/m2. At 80 mg/m2, two patients manifested grade 2 neutropenia. At least grade 3 neutropenia occurred in all patients receiving 120 mg/m2. Alopecia and subjective intolerance were mild. Cardiotoxicity was not observed except for an episode of arrhythmia in a patient with lung cancer and prior radiation. Only one minor objective response was observed in this population of refractory solid tumors. Pharmacokinetics differed from those of the free drug with no detection of daunorubicinol. We recommend future phase II studies with a dose of 100 mg/m2 in previously treated and 120 mg/m2 of DaunoXome in previously untreated patients with solid tumors.EDW is supported in part by ACS award 92-14-1 相似文献
37.
Different mechanisms by which anti-DNA MoAbs bind to human endothelial cells and glomerular mesangial cells. 下载免费PDF全文
T M Chan G Frampton N A Staines P Hobby G J Perry J S Cameron 《Clinical and experimental immunology》1992,88(1):68-74
The mechanisms by which anti-DNA MoAbs derived from MRL-lpr/lpr mice, bind to human umbilical vein endothelial cells (HUVEC) and glomerular mesangial cells were studied using a cellular ELISA. DNAse-treatment of either the MoAb or HUVEC followed by reconstitution with DNA and/or histones was performed to determine whether DNA and histones mediated such binding. It was found that MoAb410 bound to HUVEC and mesangial cells in the form of preformed DNA/anti-DNA immune complex, and such binding was facilitated by histones. In contrast, MoAb 152 bound directly to cell membrane-associated DNA, and adding DNA to MoAb 152 reduced its cellular binding. DNA binds endothelial cell surface and histones enhance the binding of both MoAb 410 and MoAb 152 to HUVEC by increasing cell membrane-associated DNA. Finally, the degree of MoAb binding to HUVEC is critically influenced by the relative concentrations of antibody, DNA, and histones. 相似文献
38.
A review of incisional hernia repairs: preoperative weight loss and selective use of the mesh repair 总被引:3,自引:0,他引:3
At the Shouldice Clinic pre-operative weight loss is used prior to incisional hernia repairs. Mesh repair is selectively used, based on specific hernia characteristics. A series of 236 patients were reviewed and followed up for 36 months. Data were available on 188 patients (80%). There were 15 recurrences (8%). The number of obese patients was reduced from 67 (35.6%) to 25 (13.3%) through the weight loss program. The hernia diameter, gastrointestinal complications, and surgical site infection were significantly related to recurrence but not the type of repair, obesity, location, or previous recurrences. The risk factors of incisional hernias include size, intestinal complications and infections. A selective use has a comparable result to the exclusive use of mesh repair. Weight reduction has yet to be shown to affect the rate of recurrence, and further prospective studies are required. 相似文献
39.
Do ethnicity and gender have an impact on pain thresholds in minor dermatologic procedures? 总被引:3,自引:0,他引:3
Gil Yosipovitch Gregory Meredith Yiong Huak Chan Chee Leok Goh 《Skin research and technology》2004,10(1):38-42
Background and Objectives: The perception of pain is a personal experience influenced by many factors, including genetic, ethnic and cultural issues. Understanding these perceptions is especially important in dermatologic patients undergoing minor surgical operations and who often differ in their pain response to surgical treatments. Little is known about how these differences affect the perception of experimental pain. The purpose of this study was to determine experimental pain perception differences in three distinct East Asian ethnic populations.
Methods: Pain thresholds were examined with a psychophysical computerized quantitative thermal sensory testing device (TSA 2001) in healthy volunteers recruited from three different Asian ethnic groups. Using the methods of limits, experimental pain perception threshold was measured on the forehead and volar aspect of the forearm in 49 healthy subjects. The measurements were then repeated after skin barrier perturbation with adhesive tape stripping of the stratum corneum. All three ethnic groups were analyzed separately with respect to age, gender educational level and skin type.
Results: A total of 20 Chinese, 14 Malay and 15 Indian subjects completed the study. Thermal pain thresholds were similar in all three ethnic groups before and after tape strippings. No significant differences were noted between genders.
Conclusions: Using quantitative sensory thermal testing, we demonstrated that no significant differences in pain occur between different races and genders. 相似文献
Methods: Pain thresholds were examined with a psychophysical computerized quantitative thermal sensory testing device (TSA 2001) in healthy volunteers recruited from three different Asian ethnic groups. Using the methods of limits, experimental pain perception threshold was measured on the forehead and volar aspect of the forearm in 49 healthy subjects. The measurements were then repeated after skin barrier perturbation with adhesive tape stripping of the stratum corneum. All three ethnic groups were analyzed separately with respect to age, gender educational level and skin type.
Results: A total of 20 Chinese, 14 Malay and 15 Indian subjects completed the study. Thermal pain thresholds were similar in all three ethnic groups before and after tape strippings. No significant differences were noted between genders.
Conclusions: Using quantitative sensory thermal testing, we demonstrated that no significant differences in pain occur between different races and genders. 相似文献
40.