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991.

Background  

In the working population, back disorders are an important reason for sick leave and permanent work inability. In the context of fitting the job to the worker, one of the primary tasks of the occupational health physician is to evaluate the balance between work-related and individual variables. Since this evaluation of work capacity often consists of a physical examination of the back, the objective of this study was to investigate whether a physical examination of the low back, which is routinely performed in occupational medicine, predicts the development of low back pain (LBP).  相似文献   
992.
993.

OBJECTIVES

To compare the oncological outcome of patients with pT3 renal tumours treated either by laparoscopic radical nephrectomy (LRN) or open RN (ORN).

PATIENTS AND METHODS

In a retrospective review of a multi‐institutional database, we identified 1003 patients with a T3N0M0 renal tumour and with no vena caval invasion. Sixty‐five patients treated by LRN were matched with up to four patients treated by ORN. Exact matches were made for age, gender, tumour size, perirenal fat invasion, renal vein invasion, and histological subtype. Following the matching process there were 44 patients treated by LRN and 135 by ORN. Qualitative and continuous variables were compared using chi‐square and independent‐sample t‐tests, respectively. Differences in survival were compared using the Kaplan‐Meier method. A Cox regression model was used to test the effect of variables on survival.

RESULTS

The two groups were comparable for age (P = 0.4), gender, tumour size (P = 0.4), tumour grade (P = 0.25) and histological subtype (P = 0.45). The mean follow‐up was longer in the ORN group (55 vs 28 months, P < 0.001). There was no difference in survival between the ORN and LRN groups in the whole T3 population (P = 0.7), in those with perirenal fat invasion (P = 0.9), or in the subset with renal vein invasion (P = 0.31). In univariate analysis, the only predictor for death from cancer was tumour grade (P = 0.05). In multivariate analysis, no variable was significantly associated with cancer survival.

CONCLUSIONS

LRN has no adverse effect on cancer survival compared to ORN in patients with microscopic T3 renal cancer. Additional prospective evaluation is warranted.  相似文献   
994.
995.
Abstract: Background: The microcirculation was assessed in the livers of human decay accelerating factors (hDAF) and wild‐type transgenic rats by fluorescent intravital microscopy, histology and histomorphology to determine the benefits of hDAF expression for the microcirculation of a rat liver xenograft perfused with human blood. Methods: Male hDAF transgenic rats (group A; n = 20) and wild‐type Sprague–Dawley rats (group B; n = 20) were xenoperfused with human blood, while other male wild‐type Sprague–Dawley rats (group C; n = 10) were perfused with allogeneic blood. Following plasma and leukocyte staining with fluorescein sodium, and platelet staining with rhodamine, the right lobe of the liver was assessed by intravital microscopy, counting the numbers of perfused sinusoids and leukocytes adhering to the endothelium per mm2, and calculating the acinar perfusion index (Pi). The liver underwent histological assessment at the end of each experiment. Mean ± SEM values were calculated and the Mann–Whitney U‐test was used for statistical analysis. Results: The number of perfused sinusoids was higher in the group of hDAF rat livers (group A) and controls (group C) than in the group of non‐transgenic rat livers perfused with human blood (group B) (P < 0.05), although only group C still had a significantly more perfused sinusoids than the other groups after 90 min of perfusion (P < 0.05). The acinar perfusion index was higher in groups A and C than in group B (P < 0.05); here again, only group C still had a significantly higher Pi than group B after 90 min of perfusion (P < 0.05). There was a massive accumulation of leukocytes that peaked after 5 min and persisted throughout the perfusion in all three groups. Histology showed portal and subendothelial hepatic vein hemorrhage, necrosis and inflammatory reaction, which were particularly evident in group B. Conclusion: In our study, rat livers transgenic for hDAF were better protected against early tissue damage by perfusion with human blood, but this did not result in a longer xenograft survival.  相似文献   
996.
Epidemiological evidence clearly identifies chronic infection with hepatitis C virus (HCV) as a major risk factor for the development of hepatocellular carcinoma (HCC). Among the mechanisms that have been implicated in the pro-carcinogenic effect of HCV infection, an increased production of reactive oxygen species in the liver seems to have a major pathogenetic role in leading from chronic inflammation to cancer. Recent data have also demonstrated that HCV is capable of inducing this active production of free radicals per se, not just through inflammation, a feature peculiar to this virus and the specific activity of its core protein. This paper provides an overview of the inter-relationships between HCV, liver damage, free radical production and HCC, describing at least in part the complex network involving DNA oxidative damage, cytokine synthesis, proto-oncogene activation and oestrogen receptor expression, that may all be deeply involved in liver carcinogenesis.  相似文献   
997.
998.
BACKGROUND: We have previously described two cases of HIV-1-positive patients undergoing surgery for stenosis of the internal carotid arteries. Histology revealed an extensive inflammatory infiltration of the vascular wall and no evidence of atheromasic plaque. This unexpected pattern of carotid damage prompted us to perform a more accurate investigation of the characteristics of carotid plaques in a group of HIV-positive patients. The results were compared with those obtained from young patients affected by atherosclerosis of the epi-aortic vessels and patients with arteritis. METHODS: The patients underwent ultrasonography of the epi-aortic vessels using one of the latest generation power color-Doppler with 7.5 MHz probes. RESULTS: The study population included 61 HIV-positive patients and 47 HIV-negative patients (37 atherosclerotic and 10 with arteritis). Compared with HIV-negative atherosclerotic patients, there were significantly higher proportions of HIV-positive patients with iso-hypoechogenic lesions (81.8 vs. 29%) that were homogeneous both in their parietal and endoluminal portions (96.7 vs. 21.6% and 88.5 vs. 54.0%, respectively), with a smooth or slightly irregular surface (99.0 vs. 56.7%) (P=0.001 for all differences). No statistically significant differences were seen between HIV-positive and arteritis patients. CONCLUSION: Our study evidenced that the ultrasonographic structure of the epi-aortic lesions in HIV-positive patients substantially differ from those of the plaques in atherosclerotic patients, although they share similar characteristics with patients affected by arteritis. Further investigations are warranted to better define the structure and the mechanism of onset of these lesions.  相似文献   
999.
AIM: To assess the performance of several noninvasive markers and of our recently proposed stepwise combination algorithms to diagnose significant fibrosis (F ≥ 2 by METAVIR) and cirrhosis (F4 by METAVIR) in chronic hepatitis B (CHB).
METHODS: One hundred and ten consecutive patients (80 males, 30 females, mean age: 42.6 ± 11.3) with CHB undergoing diagnostic liver biopsy were included. AST-to-Platelet ratio (APRI), Forns' index, AST-to-ALT Ratio, Goteborg University Cirrhosis Index (GUCD, Hui's model and Fibrotest were measured on the day of liver biopsy. The performance of these methods and of sequential algorithms combining Fibrotest, APRI and biopsy was defined by positive (PPV) and negative (NPV) predictive values, accuracy and area under the curve (AUC).
RESULTS: PPV for significant fibrosis was excellent (100%) with Forns and high (〉 92%) with APR1, GUCI, Fibrotest and Hui. However, significant fibrosis could not be excluded by any marker (NPV 〈 65%). Fibretest had the best PPV and NPV for cirrhosis (87% and 90%, respectively). Fibrotest showed the best AUC for both significant fibrosis and cirrhosis (0.85 and 0.76, respectively). Stepwise combination algorithms of APR1, Fibrotest and biopsy showed excellent performance (0.96 AUC, 100% NPV) for significant fibrosis and 0.95 AUC, 98% NPV for cirrhosis, with 50%-80% reduced need for liver biopsy.
CONCLUSION: In CHB sequential combination of APRI, Fibrotest and liver biopsy greatly improves the diagnostic performance of the single non-invasive markers. Need for liver biopsy is reduced by 50%-80% but cannot be completely avoided. Non-invasive markers and biopsy should be considered as agonists and not antagonists towards the common goal of estimating liver fibrosis.  相似文献   
1000.
Bortezomib is a new proteasome inhibitor with a high antitumor activity, but also with a potentially severe peripheral neurotoxicity. To establish a preclinical model and to characterize the changes induced on the peripheral nerves, dorsal root ganglia (DRG) and spinal cord, bortezomib was administered to Wistar rats (0.08, 0.15, 0.20, 0.30 mg/kg/day twice [2q7d] or three times [3q7d] weekly for a total of 4 weeks). At baseline, on days 14, 21 and 28 after the beginning the treatment period and during a 4-week follow-up period sensory nerve conduction velocity (SNCV) was determined in the tail of each animal. Sciatic nerve, DRG and spinal cord specimens were processed for light and electron microscope observations and morphometry. At the maximum tolerated dose bortezomib induced a significant reduction in SNCV, with a complete recovery at the end of the follow-up period. Sciatic nerve examination and morphometric determinations demonstrated mild to moderate pathological changes, involving predominantly the Schwann cells and myelin, although axonal degeneration was also observed. Bortezomib-induced changes were also observed in DRG and they were represented by satellite cell intracytoplasmatic vacuolization due to mitochondrial and endoplasmic reticulum damage, closely resembling the changes observed in sciatic nerve Schwann cells. Only rarely did the cytoplasm of DRG neurons has a dark appearance and clear vacuoles occurring in the cytoplasm. Spinal cord was morphologically normal. This model is relevant to the neuropathy induced by bortezomib in the treatment of human malignancies and it could be useful in increasing our knowledge regarding the mechanisms underlying bortezomib neurotoxicity.  相似文献   
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