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151.
We review eight cases of early gastric cancer which occurred in five female and three male patients. In seven patients the main complaint was epigastric pain and in one melena. In seven of the eight cases, endoscopic diagnosis was established on the first examination and confirmed by biopsy. Types of early gastric cancer observed were: type I, one case; IIa, one case; IIc three cases: III, two cases and type III + IIc, one case. In five cases the neoplasia was located in the antrum, two in the pre-pyloric region, two along the greater curvature and one in the anterior wall. Three cases were located in the body of the stomach, two in the lower third of the lesser curvature and one in the upper third of the greater curvature. From the histopathologic standpoint four cases were differentiated adenocarcinomas, three undifferentiated adenocarcinomas and one case mucus carcinoma. In no case did we encounter regional lymph node metastases. Postoperative survival rates at the present time varies between one and five years.  相似文献   
152.
153.

Purpose

The murine calvarial model has been widely employed for the in vivo study of particle-induced osteolysis, the most frequent cause of aseptic loosening of total joint replacements. Classically, this model uses an open surgical technique in which polyethylene (PE) particles are directly spread over the calvarium for the induction of osteolysis. We evaluated a minimally invasive modification of the calvarial model by using a direct subcutaneous injection of PE particles.

Methods

Polyethylene (PE) particles were injected subcutaneously over the calvaria of C57BL6J ten-week-old mice (“injection” group) or were implanted after surgical exposure of the calvaria (“open” group) (n = 5/group). For each group, five additional mice received no particles and served as controls. Particle-induced osteolysis was evaluated two weeks after the procedure using high-definition microCT imaging.

Results

Polyethylene particle injection over the calvaria resulted in a 40 % ± 1.8 % decrease in the bone volume fraction (BVF), compared to controls. Using the “open surgical technique”, the BVF decreased by 16 % ± 3.8 % as compared to controls (p < 0.0001).

Conclusions

Direct subcutaneous injection of PE particles over the murine calvaria produced more profound resorption of bone. Polyethylene particle implantation by injection is less invasive and reliably induces osteolysis to a greater degree than the open technique. This subcutaneous injection method will prove useful for repetitive injections of particles, and the assessment of potential local or systemic therapies.  相似文献   
154.
To study adherence to product use prior to a Phase I microbicide trial, we recruited young men who have sex with men (YMSM) with a history of unprotected receptive anal intercourse (RAI) and provided them with 40 rectal applicators containing a placebo gel to use prior to RAI during a 12-week period. Ninety-five YMSM completed the trial. Based on a Computer Assisted Self Interview, 83 participants had receptive anal intercourse (RAI) (Median 12 occasions) using gel on 82.4 % of occasions (SD 26.7; 0–100). Based on an interactive voice response system, 88 participants had RAI (Median 10 occasions) using gel on 87.9 % of occasions (SD 20.0; 20–100). By applicator counts the median gel use was 12. Participants showed high adherence to gel use. Those who did not use the product consistently (n = 40) adduced not having it with them (85 %), forgetting to use it (48 %), not wanting to use it (13 %), partner refusal (10 %) and gel messiness (10 %).  相似文献   
155.

Background

A major barrier to the use and scale-up of evidence-based interventions are challenges related to training and capacity building. A cost-effective and highly interactive multi-user virtual environment, Second Life (SL) is a promising alternative for comprehensive face-to-face facilitator training.

Objective

The purpose of this study was to examine the feasibility of using SL to train facilitators from community-based organizations to use ¡Cuídate! (Take Care of Yourself), one of the few evidence-based interventions developed and tested with Latino youth to reduce sexual risk behaviors.

Methods

We recruited 35 participants from community-based organizations throughout the United States to participate in the SL ¡Cuídate! Training of Facilitators. Preparation to use SL consisted of four phases: (1) recruitment and computer capacity screening, (2) enrollment, (3) orientation to the SL program, and (4) technical support throughout the synchronous training sessions. Technical difficulties, the associated cause, and the mitigation strategy implemented were recorded during each session. Participants completed evaluations including perceptions of self-efficacy and confidence to complete the necessary skills to participate in SL training.

Results

Overall, participants reported high levels of self-efficacy for all skills necessary to participate in SL training. Based on an 11-point scale (0-10), self-efficacy to download and access the software was rated the highest: mean 8.29 (SD 2.19). Interacting with items in SL had the lowest mean score: mean 7.49 (SD 2.89). The majority of technical difficulties experienced by participants were related to inadequate Internet connections or computer malfunctions.

Conclusions

Our findings support the feasibility of using SL for the ¡Cuídate! Training of Facilitators. The process used in this study to prepare participants to use SL can be used as a basis for other evidence-based intervention training in SL. This study is an important contribution to developing cost-effective and accessible training options for evidence-based interventions.  相似文献   
156.
157.
AIM: The aim of the present study is to evaluate the prognostic influence of loss of heterozygosity on 2p, 3p, 5q, 17p and 18q, and c-myc overexpression on surgically treated sporadic colorectal carcinoma. METHODS: Tumor and non-tumor tissue samples from 153 patients were analyzed. Fifty-one percent of patients were male, and mean age in the series was 67 years. Tumors were located in the proximal colon in 37 cases, in the distal bowel in 37, and in the rectum in 79 patients. c-myc overexpression was studied by means of Northern blot analysis, and loss of heterozygosity through microsatellite analysis. RESULTS: c-myc overexpression was detected in 25% of cases, and loss of heterozygosity in at least one of the studied regions in 48%. There was no association between clinical and pathologic features, and genetic alterations. The disease-free interval was significantly shorter for patients with both genetic alterations; the presence of both events was an independent prognostic factor for poor outcome in the multivariate analysis (RR: 4.34, p < 0.0001). CONCLUSIONS: The presence of both loss of heterozygosity and overexpression of the c-myc oncogene separates a subset of colorectal carcinoma patients who have a shorter disease-free interval after curative-intent surgery.  相似文献   
158.
The optimal management of chronic pure red cell aplasia caused by parvovirus B19 (B19-PRCA) in patients with AIDS is unclear. Our purpose was to determine the effects of intravenous immunoglobulin (IVIg) in the treatment of B19-PRCA in patients with AIDS. The patients were eight adults with AIDS admitted during the period 1993-1997. A diagnosis of B19-PRCA was made if all the following criteria were met: 1. Bone marrow biopsy finding of pure red cell aplasia; 2. Detection of parvovirus B19 DNA in serum; and 3. No alternative explanation for PRCA. Initial (induction) therapy was with IVIg 1 g/kg daily for 1-2 days. Relapses were treated with IVIg 1 g/kg for 2 days. Maintenance therapy with IVIg 0.4-1.0 g/kg q 4 weeks was given to those patients who developed a second or subsequent relapse. The patients were followed for a mean of 27 months (range 8-38 months). All patients responded to initial therapy with IVIg. Six patients with CD4 counts < 80 cells/mm3 relapsed. The response was short lived in two patients with a CD4 count < 80 cells/mm3 who were given a single infusion of IVIg 1 g/kg as initial therapy. Four patients were given regular maintenance IVIg therapy following a second or subsequent relapse and remain in remission. Two patients whose CD4 counts were > 300 cells/mm3 remain in continuous unmaintained remission from B19-PRCA for over 8 and 11 months, respectively, following induction therapy with IVIg. AIDS patients with B19-PRCA respond well to therapy with IVIg 2 g/kg given over 2 days. Most patients with CD4 counts of < or = 80 cells/mm3 suffer relapse within six months necessitating retreatment with IVIg; maintenance therapy with IVIg 0.4 g/kg q 4 weeks is effective in preventing relapse of B19-PRCA, and may be cost effective. Routine maintenance therapy is probably not indicated in patients with CD4 counts over 300 cells/mm3. Prospective studies are needed to confirm these findings.  相似文献   
159.
PURPOSE: Our previous experience with the traditional management of infected prosthetic arterial grafts, which included graft excision and vein patch repair of the involved artery, was complicated by a high incidence of vein patch rupture. This study assessed the treatment of infected prosthetic grafts with subtotal graft excision and oversewing of small graft remnants. METHODS: During the last 20 years, we treated 53 wounds involving 45 infected prosthetic grafts in 42 patients by means of subtotal graft excision and oversewing of a residual 2- to 3-mm graft remnant (patch) at an intact arterial anastomosis. This technique was selectively used to maintain patency of small-diameter arteries (41 common femoral, five deep femoral, three axillary, two iliac, and two popliteal), which were critical for limb salvage or amputation healing. This strategy avoided difficult dissection of the underlying artery in scarred wounds and obviated the placement of a new patch in an infected field. Graft remnants were polytetrafluoroethylene in 51 cases and Dacron in two cases. Of the 45 grafts, 31 were occluded and 14 were patent. All infected tissue was widely debrided, wet-to-dry dressing changes were performed three times daily, and appropriate intravenous antibiotics were administered for at least 1 week. Secondary bypass grafting procedures were performed as needed to achieve limb salvage. The follow-up period in surviving patients averaged 32 months (range, 1 to 218 months). RESULTS: No complications were directly attributable to prosthetic patch remnants in 92% of cases (49 of 53 cases). Six of 42 patients (14%) died during hospitalization (three of cardiac complications and three of sepsis with multiple organ failure). Two infected pseudoaneurysms developed 8 and 34 months after surgery, and two wounds failed to heal. Sixteen secondary bypass grafting procedures were necessary to achieve limb salvage. Patch oversewing led to limb salvage without the need for secondary revascularization in 26 other cases and to the successful healing of 10 amputated limbs when secondary revascularization was not possible. CONCLUSION: Prosthetic patch remnants are a useful adjunct that simplify management of infected prosthetic grafts, are associated with a low incidence of wound complications, and help maintain patency of essential collaterals to achieve limb salvage or heal an amputation.  相似文献   
160.

Objective.

Breast cancer is a leading cause of morbidity and mortality in Mexico. We assessed the effectiveness of a train-the-trainer program in two Mexican states in improving knowledge among professional and nonprofessional community health workers.

Materials and Methods.

We worked with local organizations to develop and implement a train-the-trainer program to improve breast cancer knowledge among community health workers, including professional health promoters (PHPs) who were trained and then trained nonprofessional community health promoters (CHPs). We surveyed participants before and after training that included in-person and online classes and again approximately 3 months later. We used paired t tests and chi-square tests to compare survey responses at the different times. We also used logistic regression to assess whether promoter characteristics were associated with greater improvements in breast cancer knowledge after training.

Results.

Overall, 169 PHPs (mean age, 36 years) completed training and provided a 10-hour training course to 2,651 CHPs, who also completed the pre- and post-training survey. For both PHPs and CHPs, post-training surveys demonstrated increases in an understanding of breast cancer as a problem; an understanding of screening, treatment, and insurance coverage issues; and knowledge of breast cancer risk factors, symptoms, and what constitutes a family history of breast cancer (all p < .05). These improvements were maintained 3 to 6 months after training.

Conclusion.

Train-the-trainer programs hold promise for leveraging community health workers, who far outnumber other health professionals in many low- and middle-income countries, to engage in health promotion activities for cancer and other noncommunicable diseases.  相似文献   
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