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81.
Only 10% to 20% of patients with pancreatic cancer are considered candidates for curative resection at the time of diagnosis. We postulated that preoperative chemoradiation therapy might promote tumor regression, eradicate nodal metastases, and allow for definitive surgical resection in marginally resectable patients. The objective of this study was to evaluate the effect of a preoperative chemoradiation therapy regimen on tumor response, resectability, and local control among patients with marginally resectable adenocarcinoma of the pancreas and to report potential treatment-related toxicity. Patients with marginally resectable adenocarcinoma of the pancreas (defined as portal vein, superior mesenteric vein, or artery involvement) were eligible for this protocol. Patients received 50.4 to 56 Gy in 1.8 to 2.0 Gy/day fractions with concurrent protracted venous infusion of S-fluorouracil (250 mg/m2/day). Reevaluation for surgical resection occurred 4 to 6 weeks after therapy. Fifteen patients (9 men and 6 women) completed preoperative chemoradiation without interruption. One patient required a reduction in the dosage of S-fluorouracil because of stomatitis. Acute toxicity from chemoradiation consisted of grade 1 or 2 nausea, vomiting, diarrhea, stomatitis, palmar and plantar erythrodysesthesia, and hematologic suppression. CA 19-9 levels declined in all nine of the patients with elevated pretreatment levels. Nine of the 1.5 patients underwent a pancreaticoduodenectomy, and all had uninvolved surgical margins. Two of these patients had a complete pathologic response, and two had microscopic involvement of a single lymph node. With a median follow-up of 30 months, the median survival for resected patients was 30 months, whereas in the unresected group median survival was 8 months. Six of the nine patients who underwent resection remain alive and disease free with follow-up of 12, 30, 30, 34, 39, and 72 months, respectively. Preoperative chemoradiation therapy is well tolerated. It may downstage tumors, sterilize regional lymph nodes, and improve resectability in patients with marginally resectable pancreatic cancer. Greater patient accrual and longer follow-up are needed to more accurately assess its future role in therapy. Presented at the Eighty-Second Annual Meeting of the American Radium Society, London, England, April l–5, 2000.  相似文献   
82.
Multiple cell types infiltrate acutely rejecting renal allografts. Typically, monocytes and T cells predominate. Although T cells are known to be required for acute rejection, the degree to which monocytes influence this process remains incompletely defined. Specifically, it has not been established to what degree monocytes impact the clinical phenotype of rejection or how their influence compares to that of T cells. We therefore investigated the relative impact of T cells and monocytes by correlating their presence as measured by immunohistochemical staining with the magnitude of the acute change in renal function at the time of biopsy in 78 consecutive patients with histological acute rejection. We found that functional impairment was strongly associated with the degree of overall cellular infiltration as scored using Banff criteria. However, when cell types were considered, monocyte infiltration was quantitatively associated with renal dysfunction while T-cell infiltration was not. Similarly, renal tubular stress, as indicated by HLA-DR expression, increased with monocyte but not T-cell infiltration. These data suggest that acute allograft dysfunction is most closely related to monocyte infiltration and that isolated T-cell infiltration has less acute functional impact. This relationship may be useful in assigning acute clinical relevance to biopsy findings.  相似文献   
83.

Introduction

Several approaches have been taken to reduce pre-antiretroviral therapy (ART) losses between HIV testing and ART initiation in low- and middle-income countries, but a systematic assessment of the evidence has not yet been undertaken. The aim of this systematic review is to assess the potential for interventions to improve or facilitate linkage to or retention in pre-ART care and initiation of ART in low- and middle-income settings.

Methods

An electronic search was conducted on Medline, Embase, Global Health, Web of Science and conference databases to identify studies describing interventions aimed at improving linkage to or retention in pre-ART care or initiation of ART. Additional searches were conducted to identify on-going trials on this topic, and experts in the field were contacted. An assessment of the risk of bias was conducted. Interventions were categorized according to key domains in the existing literature.

Results

A total of 11,129 potentially relevant citations were identified, of which 24 were eligible for inclusion, with the majority (n=21) from sub-Saharan Africa. In addition, 15 on-going trials were identified. The most common interventions described under key domains included: health system interventions (i.e. integration in the setting of antenatal care); patient convenience and accessibility (i.e. point-of-care CD4 count (POC) testing with immediate results, home-based ART initiation); behaviour interventions and peer support (i.e. improved communication, patient referral and education) and incentives (i.e. food support). Several interventions showed favourable outcomes: integration of care and peer supporters increased enrolment into HIV care, medical incentives increased pre-ART retention, POC CD4 testing and food incentives increased completion of ART eligibility screening and ART initiation. Most studies focused on the general adult patient population or pregnant women. The majority of published studies were observational cohort studies, subject to an unclear risk of bias.

Conclusions

Findings suggest that streamlining services to minimize patient visits, providing adequate medical and peer support, and providing incentives may decrease attrition, but the quality of the current evidence base is low. Few studies have investigated combined interventions, or assessed the impact of interventions across the HIV cascade. Results from on-going trials investigating POC CD4 count testing, patient navigation, rapid ART initiation and mobile phone technology may fill the quality of evidence gap. Further high-quality studies on key population groups are required, with interventions informed by previously reported barriers to care.  相似文献   
84.

Purpose

We evaluated factors influencing re-operation in tension band and plating of isolated olecranon fractures.

Methods

Four hundred eighty-nine patients with isolated olecranon fractures who underwent tension band (TB) or open reduction internal fixation (ORIF) from 2003 to 2013 were identified at an urban level 1 trauma centre. Medical records were reviewed for patient information and complications, including infection, nonunion, malunion, loss of function or hardware complication requiring an unplanned surgical intervention. Electronic radiographs of these patients were reviewed to identify Orthopaedic Trauma Association (OTA) fracture classification and patients who underwent TB or ORIF.

Results

One hundred seventy-seven patients met inclusion criteria of isolated olecranon fractures. TB was used for fixation in 43 patients and ORIF in 134. No statistical significance was found when comparing complication rates in open versus closed olecranon fractures. In a multivariate analysis, the key factor in outcome was method of fixation. Overall, there were higher rates of infection and hardware removal in the TB compared with the ORIF group.

Conclusions

Our results demonstrate that the dominant factor driving re-operation in isolated olecranon fractures is type of fixation. When controlling for all variables, there is an increased chance of re-operation in patients with TB fixation.  相似文献   
85.
86.
BackgroundAdult imaging for blunt cerebrovascular injuries (BCVI) is based on the Denver and Memphis screening criteria where CT angiogram (CTA) is performed for any one of the criteria being positive. These guidelines have been extrapolated to the pediatric population. We hypothesize that the current adult criteria applied to pediatrics lead to unnecessary CTA in pediatric trauma patients.Study designAt our center, a 9-year retrospective study revealed that strict adherence to the Denver and Memphis criteria would have resulted in 332 unnecessary CTAs out of 2795 trauma patients with only 0.3% positive for BCVI. We also conducted a retrospective chart review of 776,355 pediatric trauma patients in the National Trauma Data Bank (NTDB) from 2007 to 2014. Data collection included children between ages 0 and 18, ICD-9 search for blunt cerebrovascular injury, and ICD-9 codes that applied to both Denver and Memphis criteria.ResultsOf 776,355 pediatric trauma activations, 81,294 pediatric patients in the NTDB fit the Denver/Memphis criteria for screening CTA neck or angiography based on ICD-9 codes, while only 2136 patients suffered BCVI. Strict utilization of the Denver/Memphis criteria would have led to a negative CTA in 79,158 (97.4%) patients. Multivariate regression analysis indicates that patients with skull base fracture, cervical spine fractures, cervical spine fracture with cervical cord injury, traumatic jugular venous injury, and cranial nerve injury should be considered part of the screening criteria for BCVI.ConclusionOur study suggests the Denver and Memphis criteria are inadequate screening criteria for CTA looking for BCVI in the pediatric blunt trauma population. New criteria are needed to adequately indicate the need for CT angiography in the pediatric trauma population.Level of evidenceIV.  相似文献   
87.
BACKGROUND: To evaluate the results of the tension-free vaginal tape procedure (TVT) from a patient's perspective. METHODS: Between May 1999 and January 2002, 90 patients underwent a TVT for genuine stress incontinence (GSI) and mixed incontinence. Prior to the procedure, GSI was confirmed by clinical examination and urodynamic studies. Results were then audited from patient notes and the same patients were sent questionnaires to examine results from a patient perspective. RESULTS: Overall response rate to the questionnaire was 70 (77%). The mean age of the patients was 50.4 years (range 31-83 years). Sixty-one patients had spinal anesthesia, seven had general anesthesia and two had local anesthesia. Mean hospital stay was 3.36 days (range 2-14 days) and mean period from the operation to the time of the survey and audit was 16.34 months (range 3-28; SD 6.92). Thirty-nine (56%) of the 70 patients who answered said that the operation had cured their incontinence, 16 (23%) had an improvement in their symptoms, 7 (10%) had worsening of their symptoms and 8 (11%) felt that the operation did not make any difference. The overall success rate according to the patients' perspective was 79%, whereas our audit showed an overall success rate of 86% (77% and 82%, respectively, when we compared only the 66 patients who had both notes and replies available for analysis). CONCLUSION: Although a patient's perception regarding the success of TVT tends to differ from that of a clinician, it was not found to be statistically significant (P = 0.22, McNemar test). The TVT is a very successful operation, but realistic cure rates should be offered to patients.  相似文献   
88.
BACKGROUND: A limited number of studies have assessed the changes in bone microarchitecture in spinal facets with use of light microscopy but not with use of electron microscopy techniques. The purpose of this study was to analyze the facets in patients with scoliosis to determine whether there are differences in the bone microarchitecture of contralateral facets at the same anatomic level. METHODS: In eight patients undergoing posterior spinal arthrodesis for the treatment of idiopathic scoliosis, biopsy specimens of facet pairs at matched anatomic levels were obtained from three locations: (1). the curve apex, (2). one level cephalad to the apex, and (3). one level caudad to the apex. The facets were analyzed for cortical bone porosity and thickness with use of scanning electron microscopy and National Institutes of Health imaging software. The concave and convex facets were compared with use of a paired t test. RESULTS: The mean porosity (and standard deviation) for the concave and convex facets was 16.5% +/- 5.8% and 24.1% +/- 6.2%, respectively. Those on the convex side were significantly more porous than those on the concave side (p 相似文献   
89.
Introduction. Restitution of the intestinal barrier requires inter-enterocyte communication via the phosphorylated gap junction protein connexin 43. Experimental necrotizing enterocolitis (NEC) is characterized by elevated interferon gamma (IFN) and impaired restitution. We therefore hypothesized that IFN impairs gap junction (GJ) function and restitution by inhibiting phosphorylation of connexin43. We further sought to determine whether connexin 43 phosphorylation was altered in human NEC. Methods. Connexin 43 expression and phosphorylation was assessed in IEC-6 cells ± IFN (1000 u/ml) by SDS--PAGE and confocal microscopy. GJ function was detected by microinjecting IEC-6 cells ± IFN with the GJ tracer lucifer yellow (LY) and impermeant rhodamine dextran. GJ function was inhibited with oleamide (10 μM). In vitro restitution was assessed using time lapsed video microscopy of IEC-6 cells ± IFN migrating across a scraped wound. Small bowel mucosal scrapings were acquired from infants undergoing bowel resection for NEC and compared to specimens taken from infants without NEC. Data are mean ± SEM. Results. IFN significantly reduced phosphorylation of connexin 43 (band density relative to actin, Ctrl: 0.86 ± 0.3 versus IFNγ 0.37 ± 0.1, P < 0.05) and decreased membrane localization of the phosphorylated gap junctions. This correlated with decreased gap junction function as detected by loss of LY transfer (levels of intercellular transfer: Ctrl: 3.2 ± 0.2, IFN 2.4 ± 0.3, oleamide 0, P < 0.05). Oleamide and IFN significantly reduced enterocyte restitution (ctrl: 5 μm/h, oleam: 1.5 μm/h, IFN: 1.6 μm/h, P < 0.05), correlating with a lack of intercellular communication. Strikingly, phosphorylation of connexin 43 in the mucosa of infants with NEC was significantly reduced as compared to control bowel, which correlated with the extent of mucosal disease. Conclusion. IFN inhibits phosphorylation of connexin 43, leading to impaired inter-enterocyte communication and reduced restitution. The finding of decreased phosphoconnexin 43 in human NEC suggests that impaired inter-enterocyte communication may underlie the barrier dysfunction in this disease.  相似文献   
90.
Although pentagastrin has a tropic action on intestinal mucosa in suckling rat pups, and at weaning a rise in gastrin levels coincides with maturation of the intestinal mucosa, direct correlations of serum gastrin levels and intestinal maturation have yet to be made. Ten-day-old rats were subjected either to antrectomy to produce a 43% decrease in serum gastrin levels or to fundectomy to produce a 319% increase over gastrin levels in rumenectomized or normal animals. These changes were not associated with tropic or adaptive changes in jejunal or colonic mucosa as determined by jejunal and colonic DNA content, jejunal sucrase activity, jejunal villous height, or crypt depths in jejunum and colon at the beginning (day 15), middle (day 21), or end (day 27) of the weaning period. To the contrary, an inverse relation was found between serum gastrin levels and both jejunal mucosal DNA content and sucrase activity as an index of maturation.  相似文献   
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