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排序方式: 共有3312条查询结果,搜索用时 390 毫秒
1.
Ragan McLeod Sunyoung Kim Sara Tomek Sara McDaniel 《Early child development and care》2019,189(8):1284-1291
Young children enter kindergarten with varying levels of readiness and abilities to learn. One factor that contributes to lower levels of school readiness is poverty. One timely, cost-effective, and feasible strategy to boost school readiness, regardless of exposure to high-quality preschool is to leverage the summer months prior to kindergarten entry and provide comprehensive, evidence-based programming immediately before the school year begins. The current study implemented a community-based summer programme targeted at improving school readiness for 25 four- and five-year-old children in a low-income community. Across the 9-week study, children participated in two types of early literacy activities and the Incredible Years social/emotional learning curriculum. Results indicate that participants demonstrated significant growth across three early literacy skills and were rated as overall stable regarding their behaviour across the summer. These results are discussed along with implications and future directions in this line of research. 相似文献
2.
Progressive, cystic tumor enlargement in the abdomen developed in a patient with teratocarcinoma during treatment with systemic chemotherapy. Tumor markers were elevated in the cyst fluid and negative in serum. Further, the patient underwent a successful surgical debulking of large amounts of cystic teratoma. 相似文献
3.
4.
Immunocytochemical study of retinal diode laser photocoagulation in the rat. 总被引:8,自引:3,他引:5
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P R Richardson M E Boulton J Duvall-Young D McLeod 《The British journal of ophthalmology》1996,80(12):1092-1098
AIM: To determine the nature of the cellular infiltrate, alterations in cell adhesion molecules, and MHC II antigen expression in the rat retina following diode laser retinal photocoagulation. METHOD: 20 normal Lister rats underwent diode laser photocoagulation of the retina. Frozen sections from eyes enucleated at 0, 1, 5, 13, and 33 days post laser were examined for T cells (R7.3), CD4 T cells (W3/25), activated CD4 T cells (OX-40), CD8 T cells (OX-8), B cells (OX-33), and macrophages (OX-42), MHC II antigen (OX-6), and E-Selectin-1, VCAM-1, and ICAM-1. RESULTS: Retinal diode laser photocoagulation stimulated a wound healing response in the outer retina and choroid. The cellular infiltrate included macrophages and activated CD4 T cells at 13 and 33 days post laser. Glial cells in the inner plexiform and inner nuclear layers expressed MHC II antigen at 24 hours only. ICAM-1 antigen was induced in RPE cells and in Muller cells in the inner retina at all time intervals post laser and intense staining for ICAM-1 was present around intraretinal migrated cells at 13 and 33 days post laser. VCAM-1 antigen expression was induced in the choroidal vascular endothelium and RPE at 13 and 33 days after laser as was E-Selectin-1 antigen expression which was also evident focally at the external limiting membrane in association with migrated cells adjacent to the burn. CONCLUSIONS: These results suggest that alterations in cell adhesion molecules may regulate the migration and activation of retinal pigment epithelium, macrophages and CD4 T cells at the outer blood-retinal barrier and choroid following diode laser photocoagulation of the normal Lister rat retina. 相似文献
5.
Question: Is there a difference in cancer-related survival between laparoscopic assisted colectomy (LAC) and open colectomy (OC)? Design: Randomized controlled trial. Setting: Single-centre trial, Barcelona, Spain. Patients: Two hundred and nineteen of 442 eligible patients with adenocarcinoma of the colon were included. Patients were excluded if the tumour was below 15 cm from the anal verge or was in the transverse colon; if there were distant metastases, adjacent organ involvement or obstruction; or the patient had previous colonic surgery. One hundred and eleven were randomized to the LAC group and 108 to the OC. Interventions: Randomization was done the day before surgery. Patients were stratified into 2 groups according to tumour location (right or left side with respect to the splenic flexure) and assigned to the LAC or OC group by means of sealed opaque envelopes containing computer-generated random numbers. Patients in both groups had surgery by a single gastrointestinal surgical team. Pre- and postoperative care was standardized for bowel prep and perioperative antibiotics. Patients received either LAC or OC using a no-touch technique and initial vascular ligation. Main outcome measure: Overall survival. Results: The Cox model showed that LAC was independently associated with reduced risk of tumour relapse (hazard ratio 0.39, 95% CI 0.19 – 0.82), death from any cause (0.48, 0.23 –1.01) and death from a cancer-related cause (0.38, 0.16– 0.91) compared with OC. This superiority of LAC was due to differences in patients with stage III tumours (freedom from recurrence p = 0.04, overall survival p = 0.02, and cancer- related survival p = 0.006).
Conclusion:
LAC is more effective than OC for treatment in terms of morbidity, hospital stay, tumour recurrence and cancer-related survival. 相似文献
6.
Retinal and preretinal localisation of epidermal growth factor, transforming growth factor alpha, and their receptor in proliferative diabetic retinopathy. 总被引:7,自引:3,他引:4
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B Patel P Hiscott D Charteris J Mather D McLeod M Boulton 《The British journal of ophthalmology》1994,78(9):714-718
A number of growth factors have been implicated in the development and perpetuation of preretinal fibrovascular membranes in patients with proliferative diabetic retinopathy (PDR). The aim of this study was to determine the potential role of epidermal growth factor (EGF), transforming growth factor alpha (TGF-alpha), and their receptor (EGF-R) in PDR development. Immunostaining for EGF, TGF-alpha, and EGF-R was compared between normal retina, PDR retina, and PDR preretinal membranes. Weak staining for EGF and EGF-R was observed throughout the neural retina from non-diabetic eyes while weak to moderate staining for TGF-alpha was observed in the ganglion cell layer and the inner and outer nuclear layers. In contrast, intense staining for EGF and TGF-alpha and moderate staining for EGF-R were observed throughout the PDR retina. Immunoreactivity for EGF, TGF-alpha, and EGF-R was seen in the majority of the 11 excised membranes studied and, though variable, was generally greater than that observed in normal retinas. These results suggest an autocrine/paracrine role for EGF, TGF-alpha, and EGF-R in PDR. 相似文献
7.
Viscodelamination at the vitreoretinal juncture in severe diabetic eye disease. 总被引:1,自引:1,他引:0
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Injection of 1% methylcellulose or 1% sodium hyaluronate (Healonid) was used to separate attached vitreous cortex and fibrovascular epiretinal membranes from the retina in 40 eyes undergoing closed microsurgery for severe diabetic eye disease. The viscodelamination technique was of great value in elevating vitreous cortex or sparsely vascularised epiretinal membranes, especially in eyes with combined traction and rhegmatogenous retinal detachment. However, bleeding from or tearing of the retina limited the usefulness of this technique in the surgery of highly vascularised and adherent membranes, as in eyes with table-top traction retinal detachment. Recurrent epiretinal membrane proliferation was seen in some eyes postoperatively. 相似文献
8.
Robin S. McLeod 《Canadian journal of surgery》1997,40(5):353-357
Local recurrence is a serious complication in patients with rectal cancer because of the frequency with which it occurs, its impact on quality of life and the fact that treatment is rarely successful. Although local recurrence rates varying from 4% to 51% have been reported, recent series have reported rates of less than 10%. Various factors may affect the rate of local recurrence, including the stage and location of the tumour. Other prognostic factors may be of importance, but it is controversial whether they are independent risk factors. Finally, there is mounting evidence that the local recurrence rate varies with the surgeon. Whether this is due to the surgical technique or surgical expertise is not clear, but randomized controlled trials addressing the issue of extent of resection are indicated in order to optimize surgical results. 相似文献
9.
J R Bishop J W Moul S A Sihelnik D S Peppas T S Gormley D G McLeod 《The Journal of urology》1992,147(2):386-388
We report an 18-month prospective study of 90 patients undergoing penile prosthesis implantation to evaluate a possible cause-and-effect relationship between degree of diabetic control and the risk of infection complicating the operation. Long-term diabetic control was objectively evaluated by measurement of the glycosylated hemoglobin of the patient, which is known to provide an objective value for degree of control for the preceding 60 to 90 days. Of 90 patients 5 (5.5%) had a periprosthetic infection requiring explantation and all infections occurred in the 32 diabetics (36%) in the population (p less than 0.009). Of the 32 diabetics 13 (41.1%) were poorly controlled with time as demonstrated by a glycosylated hemoglobin level of greater than 11.5% and 4 of the infections occurred in this group. Of the 19 remaining controlled diabetics (glycosylated hemoglobin level less than 11.5%) only 1 infection occurred. Therefore, infection occurred in 31% of the poorly controlled versus 5% of the adequately controlled patients (p less than 0.0003). Measurement of glycosylated hemoglobin values appears to be a useful tool to evaluate diabetic patients before implantation of a penile prosthesis. Patients with a glycosylated hemoglobin level of 11.5% or greater should be more optimally controlled before undergoing implantation in an effort to avoid infectious complications. 相似文献
10.
Duration of postlaparoscopic pneumoperitoneum 总被引:4,自引:0,他引:4
Background: Patients who present with abdominal pain after recent laparoscopic surgery present a diagnostic dilemma when pneumoperitoneum
is present. Previous studies do not define the duration of postlaparoscopic pneumoperitoneum. In this study, we attempted
to define the duration of laparoscopic pneumoperitoneum and to identify factors which affect resolution time.
Methods: We followed 57 patients who underwent laparoscopic cholecystectomy (34), inguinal herniorraphy (20), or appendectomy (three).
Serial abdominal films were taken until all residual gas was resolved.
Results: Thirty patients resolved their pneumoperitoneum within 24 h; 16 patients resolved between 24 h and 3 days; nine patients
resolved between 3 and 7 days; two patients resolved between 7 and 9 days. Mean resolution time for all patients was 2.6 ±
2.1 days. There was no apparent difference in resolution time between the three types of procedures; however, the sample size
may be insufficient. Duration of the pneumoperitoneum did not correlate with gender, age, weight, initial volume of CO2 used, length of time for the procedure, or postoperative complications. Sixteen patients had bile spillage during cholecystectomy
which significantly reduced the duration of postoperative pneumoperitoneum (p < 0.008), resulting in a mean resolution time of 1.3 ± 0.9 days. While 14 patients reported postoperative shoulder pain,
no correlation was found between the presence or duration of shoulder pain and the extent or duration of pneumoperitoneum.
Conclusions: We conclude that the residual pneumoperitoneum following laparoscopic surgery resolves within 3 days in 81% of patients and
within 7 days in 96% of patients. The resolution time was significantly less in patients sustaining intraoperative bile spillage
during cholecystectomy. There was no correlation found between postoperative shoulder pain and the presence or duration of
the pneumoperitoneum.
Received: 22 March 1996/Accepted: 12 July 1996 相似文献