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排序方式: 共有1615条查询结果,搜索用时 11 毫秒
1.
Head trauma     
Computed tomography is currently the modality of choice in imaging acutely traumatized patients. This is based upon CT's documented ability to detect surgically significant lesions. Furthermore, the use of MRI is limited by a lack of bone detail, the degradation of MR images in frequently uncooperative patients, and a limited supply of nonferromagnetic monitoring equipments. CT and MRI are largely equivalent in their ability to diagnose epidural hematoma, but CT is readily available and quick. MRI provides information in addition to that obtained by CT in many instances, such as subacute and chronic subdural hematomas, contusions, and intracerebral hematomas.  相似文献   
2.
Determination of hepatitis C virus genotype by Pyrosequencing   总被引:4,自引:0,他引:4  
A simple sequencing-based assay is described for genotyping of hepatitis C virus (HCV). RT-PCR was employed to amplify a 237-nucleotide-long fragment from the 5' untranslated region (UTR) of the genome using one biotinylated and one normal primer. Subsequent to capture of the PCR products on streptavidin-coated beads, single-stranded DNA separation, and hybridization of sequencing primer, Pyrosequencing was performed. The genotype of 98 samples out of which 77 samples were from American veterans and 21 samples were from Iran was determined. The samples from the American veterans contained six different subtypes, while five subtypes were found in Iranian samples. For rapid population-specific HCV subtyping, a multiplex assay was developed. This study demonstrates the suitability of this technology for low-cost, high throughput and accurate microbial genotyping.  相似文献   
3.
AIM: The aim of this study was to describe persistence of hypervascularity in proton treated hepatocellular carcinoma at serial follow-up computed tomography (CT). METHODS: Four patients with unresectable solitary hypervascular hepatocellular carcinoma underwent 55-82 Gy proton-beam irradiation for a period of 15-47 days. Follow-up CT including plain, enhanced and dynamic imaging was performed for a period of 9-36 months. RESULTS: Good preservation of arterial blood supply while gradual decrease in tumour size was clearly depicted by dynamic CT. CONCLUSION: We believe that preservation of hypervascularity as judged by enhancement at CT and magnetic resonance imaging, does not necessarily mean that radiotherapy in hypervascular malignant tumours has been unsuccessful.  相似文献   
4.
PURPOSE: Prognosis of patients with glioblastoma is poor. Therefore, in glioblastoma patients, we analyzed whether antitumor vaccination with a virus-modified autologous tumor cell vaccine is feasible and safe. Also, we determined the influence on progression-free survival and overall survival and on vaccination-induced antitumor reactivity. PATIENTS AND METHODS: In a nonrandomized study, 23 patients were vaccinated and compared with nonvaccinated controls (n = 87). Vaccine was prepared from patient's tumor cell cultures by infection of the cells with Newcastle Disease Virus, followed by gamma-irradiation, and applied up to eight times. Antitumor immune reactivity was determined in skin, blood, and relapsed tumor by delayed-type hypersensitivity skin reaction, ELISPOT assay, and immunohistochemistry, respectively. RESULTS: Establishment of tumor cell cultures was successful in approximately 90% of patients. After vaccination, we observed no severe side effects. The median progression-free survival of vaccinated patients was 40 weeks (v 26 weeks in controls; log-rank test, P = .024), and the median overall survival of vaccinated patients was 100 weeks (v 49 weeks in controls; log-rank test, P < .001). Forty-five percent of the controls survived 1 year, 11% survived 2 years, and there were no long-term survivors (> or = 3 years). Ninety-one percent of vaccinated patients survived 1 year, 39% survived 2 years, and 4% were long-term survivors. In the vaccinated group, immune monitoring revealed significant increases of delayed-type hypersensitivity reactivity, numbers of tumor-reactive memory T cells, and numbers of CD8(+) tumor-infiltrating T-lymphocytes in secondary tumors. CONCLUSION: Postoperative vaccination with virus-modified autologous tumor cells seems to be feasible and safe and to improve the prognosis of patients with glioblastomas. This could be substantiated by the observed antitumor immune response.  相似文献   
5.
Intrahepatic neutrophil infiltration has been implicated in severe alcoholic hepatitis (SAH) pathogenesis; however, the mechanism underlying neutrophil-induced injury in SAH remains obscure. This translational study aims to describe the patterns of intrahepatic neutrophil infiltration and its involvement in SAH pathogenesis. Immunohistochemistry analyses of explanted livers identified two SAH phenotypes despite a similar clinical presentation, one with high intrahepatic neutrophils (Neuhi), but low levels of CD8+ T cells, and vice versa. RNA-Seq analyses demonstrated that neutrophil cytosolic factor 1 (NCF1), a key factor in controlling neutrophilic ROS production, was upregulated and correlated with hepatic inflammation and disease progression. To study specifically the mechanisms related to Neuhi in AH patients and liver injury, we used the mouse model of chronic-plus-binge ethanol feeding and found that myeloid-specific deletion of the Ncf1 gene abolished ethanol-induced hepatic inflammation and steatosis. RNA-Seq analysis and the data from experimental models revealed that neutrophilic NCF1-dependent ROS promoted alcoholic hepatitis (AH) by inhibiting AMP-activated protein kinase (a key regulator of lipid metabolism) and microRNA-223 (a key antiinflammatory and antifibrotic microRNA). In conclusion, two distinct histopathological phenotypes based on liver immune phenotyping are observed in SAH patients, suggesting a separate mechanism driving liver injury and/or failure in these patients.  相似文献   
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Abstract:  Using lacerated livers for liver transplantation (LTx) can add an option to the extended donor criteria. We present an LTx case using a severely lacerated liver and review of the literature for reported cases. We used a high-grade lacerated liver from a 19-yr-old brain-dead patient caused by traffic accident. The liver had grade IV and II lacerations in the right and left lobe, respectively. Lacerations were managed by sealants, stitching and perihepatic packing. The liver was transplanted to a 49-yr-old man suffering from hepatocellular carcinoma on hepatitis C-induced liver cirrhosis. The two-yr follow-up was uneventful. All published LTx cases using traumatized livers (n = 18) were analyzed. The liver injury ranged from subcapsular hematoma to deep ruptures. Most reported lacerations were in the right lobe, which were managed by digital compression, suturing, electrocautery, and perihepatic packing. The reported complications were primary non- (18%), or poor function, liver abscess, bilioma, and subhepatic hematoma each in one case (5.5%). Six-month graft and patient survival were 71% and 88%, respectively. With meticulous management lacerated livers can be transplanted successfully. Because of complexity of the management, procurement and transplantation should be done by experienced liver surgeons. These organs are marginal grafts and should be offered to selected patients.  相似文献   
10.

Background

The decision to perform laparotomy in blunt trauma patients is often difficult owing to pelvic fractures; however, once the decision is made, delay or failure to perform laparotomy could affect morbidity and mortality. We sought to identify predictors of laparotomy and mortality in polytrauma patients with pelvic fractures.

Methods

We divided 390 blunt polytrauma patients (Injury Severity Score [ISS] ≥ 16) with pelvic fractures into laparotomy (n = 56) and nonlaparotomy (n = 334) groups. We assessed the role of the following variables in predicting laparotomy and mortality: age, sex, hypotension, fluid and blood transfusions, positive abdominal computed tomography (CT) scans or focused assessment with sonography for trauma (FAST) examination, pelvic fracture severity and ISS. We analyzed the data using Student t and χ2 tests, followed by logistic regression analysis.

Results

Mortality was higher in the laparotomy group than the nonlaparotomy group (28.6% v. 12.9%; overall mortality 15.1%). The laparotomy group had higher mean ISS (36.9 v. 24.9), higher mean abbreviated injury scores (AIS) for the abdomen (2.6 v. 0.9) and chest (3.4 v. 1.6), lower mean initial hemoglobin levels (105.2 v. 127.0 g/L), higher mean crystalloid (4249 v. 3436 mL) and blood transfusion volumes over 4 hours (12.1 v. 3.9 units), more frequent hypotension (44.6 v. 18.0%) and a higher percentage of positive CT scans (67.9% v. 28.4%) and FAST examination results (42.9% v. 3.3%) than the nonlaparotomy group. Age (mean 53.7 v. 41.5 yr); ISS (mean 39.0 v. 24.4); AIS for the head (mean 3.2 v. 1.7), abdomen (mean 1.6 v. 1.1), chest (mean 2.7 v. 1.8) and pelvis (mean 3.1 v. 2.6); crystalloid (mean 5157.3 v. 3266.4 mL) and blood transfusion volumes over 4 hours (mean 13.1 v. 3.7) and initial hypotension (61% v. 14.8%) were all greater among patients who died than those who survived. Mean initial hemoglobin levels were lower among patients who died than among those who survived (111.1 v. 126.2 g/L). Age, the AIS for the head, initial hypotension and low initial hemoglobin levels were highly predictive of mortality, whereas low initial hemoglobin levels, a positive FAST examination and high AIS for the abdomen and chest were all highly predictive of laparotomy.

Conclusion

Among the polytrauma patients with pelvic fractures, 14.3% underwent laparotomy, and mortality was higher among these patients than among those who did not have the procedure. The predictors of laparotomy and mortality are similar to those anticipated in patients without pelvic fractures.  相似文献   
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