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101.

Introduction

Lymph node involvement is a well-known predictor of recurrent rectal cancer in patient who did not undergo neoadjuvant therapy patients. The role of persistent lymph node disease after neoadjuvant treatment, however, is debatable. This study compares outcomes of patients with clinical, stage III rectal cancer who had nodal disease on surgical pathology after neoadjuvant treatment to patients with negative nodes.

Methods

We reviewed retrospectively a consecutive cohort of all clinical, American Joint Committee on Cancer stage III rectal cancer patients who received neoadjuvant chemoradiotherapy and had an R0 resection at the Massachusetts General Hospital between 2004 and 2015.

Results

A total of 166 patients met the inclusion criteria, of whom 53 had persistent nodal disease on pathologic examination. This group had a greater rate of local and distant disease recurrence and a shorter median recurrent disease-free survival than patients with a complete nodal response. In multivariable analyses for disease recurrence, disease free survival was greater for patients without positive results in lymph nodes on pathologic examination.

Conclusion

Persistent nodal involvement after neoadjuvant therapy is associated with an increased risk of distant metastases and a shorter disease-free survival. Identifying patients with treatment-resistant lymph nodes preoperatively and adjusting neoadjuvant treatment might result in better outcomes.  相似文献   
102.
This study was designed to examine the contribution of oxidative stress in gastrointestinal disorders after an intraperitoneal administration of 5 fluorouracil (5-FU; 100?mg/kg of body weight (b.w.)) and capecitabine oral administration (500?mg/kg b.w.). The animals were divided into three groups: Group A (NaCl,10?ml/kg of b.w.) considered as control group, group B was intoxicated by 5-FU and group C was the group of animals treated with capecitabine (CAP). To evaluate the secretory and enteropooling effects, we used magnesium sulfate (MgSO4), 1?ml/100?g of b.w. as a hypersecretion agent . The mucosal gastro-intestinal specimens were scraped and examined for biological markers of oxidative stress and intracellular mediators. These anticancer drugs caused many intestinal damages manifested by an elevation of fluid accumulation and imbalance in electrolytes secretion. The intestinal tissues from treated rats not only showed a significant increase in malondialdehyde (MDA), protein carbonylation and hydrogen peroxide (H2O2) production. but also showed a significant depletion of enzymatic and non-enzymatic antioxidant, such as, glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT) and sulfhydryl groups (-SH). These effects were related with histopathological damage and a perturbation of intracellular mediators. As expected, these disturbances were observed in the group of rats poisoned by the MgSO4. Data suggest the contribution of oxidative stress in chemotherapy-induced many disorders in intestinal tract.  相似文献   
103.
This study aimed to explore the relationship between antioxidant enzyme activities and neurological soft signs (NSS) in a sample of patients with schizophrenia. Sixty clinically stable patients with schizophrenia treated mostly by first-generation antipsychotics and 30 matched healthy controls were recruited. NSS were assessed in two groups by a standardized neurological examination (Krebs et al., 2000). The red blood cell (RBC) antioxidant activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) were measured by spectrophotometry. RBC activities of all enzymes studied: SOD, GSH-Px and CAT, were significantly lower in the patients compared to control group. All NSS scores were significantly higher in the patients compared to healthy controls' scores. In the patients, a negative correlation was found between RBC SOD activity and NSS total score and motor coordination and motor integration sub-scores. The association between low SOD activity as a marker of oxidative stress and NSS in schizophrenic patients suggests a common pathological process of these abnormalities.  相似文献   
104.
105.
The aim of this study was to assess the effect of time-of-day-specific training on the diurnal variations of short-term performances in boys. Twenty-four boys were randomized into a morning-training-group (07:00-08:00h; MTG), an evening-training-group (17:00-18:00h; ETG) and a control-group (CG). They performed four tests of strength and power (unilateral isometric maximal voluntary contraction of the knee extensor muscles, Squat-Jump, Counter-Movement-Jump and Wingate tests) at 07:00 and 17:00h just before (T0) and after 6 weeks of resistance training (T1). In T0, the results revealed that short-term performances improved and oral temperature increased significantly from morning to afternoon (amplitudes between 2.36 and 17.5% for both oral temperature and performances) for all subjects. In T1, the diurnal variations of performances were blunted in the MTG and persisted in the ETG and CG. Moreover, the training program increase muscle strength and power especially after training in the morning hours and the magnitude of gains was greater at the time-of-day-specific training than at other times. In conclusion, these results suggest that time-of-day-specific training increases the child's anaerobic performances specifically at this time-of-day. Moreover, the improvement of these performances was greater after morning than evening training.  相似文献   
106.
107.
Polymer composites have been widely used as damping materials in various applications due to the ability of reducing the vibrations. However, the environmental and surrounding thermal exposure towards polymer composites have affected their mechanical properties and lifecycle. Therefore, this paper presents the effect of material-temperature dependence on the loss factor and phase shift angle characteristics. Two types of unageing and aging silicone-rubber-based magnetorheological elastomer (SR-MRE) with different concentrations of carbonyl iron particles (CIPs), 30 and 60 wt%, are utilized in this study. The morphological, magnetic, and rheological properties related to the loss factor and phase shift angle are characterized using a low-vacuum scanning electron microscopy, and vibrating sample magnetometer and rheometer, respectively. The morphological analysis of SR-MRE consisting of 30 wt% CIPs revealed a smoother surface area when compared to 60 wt% CIPs after thermal aging due to the improvement of CIPs dispersion in the presence of heat. Nevertheless, the rheological analysis demonstrated inimitable rheological properties due to different in-rubber structures, shear deformation condition, as well as the influence of magnetic field. No significant changes of loss factor occurred at a low CIPs concentration, whilst the loss factor increased at a higher CIPs concentration. On that basis, it has been determined that the proposed changes of the polymer chain network due to the long-term temperature exposure of different concentrations of CIPs might explain the unique rheological properties of the unaged and aged SR-MRE.  相似文献   
108.
Nowadays, occupational asthma is the most common form of occupational lung disease in the world. In some countries the textile industry remains an important source of potential agents causing occupational asthma. In the textile industry several agents such as cotton dust and dyes may cause occupational asthma. In this review, we discuss the epidemiology, pathogenesis/mechanisms, clinical presentations, management and prevention specific to occupational asthma in the textile industry.Work-related asthma risk is considerable. Current understanding of the mechanisms by which many textile agents cause occupational asthma is limited, especially for low molecular-weight sensitizers and irritants. The diagnosis is generally established on the basis of a suggestive history of a temporal association between exposure and the onset of symptoms and objective evidence that these symptoms are related to airflow limitation. Early diagnosis, elimination or reduction of exposure to the offending agent and early use of convenient therapy according to disease severity may play an important role in the prevention of long-term persistence of asthma. Its prevention in the textile industry should be both technical and medical. It depends on the difficulties to reduce dust level, the limits in arranging work station or in occupational rehabilitation. These difficulties are increased in small textile industry companies. Persistent occupational asthma in this sector is often associated with substantial disability and consequent impacts on income and quality of life. Prevention of new cases is the best approach to reduce the burden of asthma attributable to occupational exposures. This review also outlines different patents on the diagnosis and treatment of asthma.  相似文献   
109.
Cutaneous and visceral leishmaniasis (VL, CL) represent the most frequent vector-borne diseases in Tunisia. Their biological confirmation is necessary before the administration of restricting, expensive and toxic specific treatments. Retrospective evaluation of the contribution of Leishmania cultures on NNN medium in leishmaniasis diagnosis have been done using the data of 375 cultures concerning 214 CL cases and 125 VL cases consecutively recruited in Pasteur Institute of Tunisia between 1995 and 2007. The global sensitivity of the culture in the course of CL was of 68.2%. It was significantly higher during zoonotic CL (78.8%) compared to that during sporadic CL (54.9%); p<0.001. This difference is explained by the easier thrust in NNN medium of Leishmania (L.) major, the agent of zoonotic CL than that of L. infantum, particularly its zymodeme MON-24, agent of sporadic CL. In the course of VL, and in spite of the better sensitivity of bone marrow aspirates (BMA) culture (70.8%), the blood buffy-coat, which permit to avoid the trauma induced by BM aspiration gave promising results (58.2%), the difference being not significant. Besides, in the course of both CL and VL, the direct examination of smears is revealed more sensitive, respectively 89.7% and 93.4% (p<0.01 and p<0.01). Although, systematic cultures practise, in parallel with direct examination, is recommended. In fact, in addition of straightening out some diagnosis, 22 cases in our series, the culture provide the isolation and the isoenzymatic identification of the causative species and strains allowing a better comprehend of parasite life cycles and a disposing of important epidemiological data for suitable control measures. As known with all cultures, those of Leishmania are also exposed to the contamination problem, which reached 5.9% in our study. In conformity with previsions, the contamination concerned much more cutaneous samples (8.4%) than blood or BM ones (2.5%; p=0.015).  相似文献   
110.
The non-decreasing incidence of HIV among men who have sex with men (MSM) has motivated the emergence of Community Based Voluntary Counselling and Testing (CBVCT) services specifically addressed to MSM. The CBVCT services are characterized by facilitated access and linkage to care, a staff largely constituted by voluntary peers, and private not-for-profit structures outside the formal health system institutions. Encouraging results have been measured about their effectiveness, but these favourable results may have been obtained at high costs, questioning the opportunity to expand the experience. We performed an economic evaluation of HIV testing for MSM at CBVCT services, and compared them across six European cities. We collected retrospective data for six CBVCT services from six cities (Copenhagen, Paris, Lyon, Athens, Lisbon, and Ljubljana), for the year 2014, on the number of HIV tests and HIV reactive tests, and on all expenditures to perform the testing activities. The total costs of CBVCTs varied from 54,390€ per year (Ljubljana) to 245,803€ per year (Athens). The cost per HIV test varied from to 41€ (Athens) to 113€ (Ljubljana). The cost per HIV reactive test varied from 1966€ (Athens) to 9065€ (Ljubljana). Our results show that the benefits of CBVCT services are obtained at an acceptable cost, in comparison with the literature (values, mostly from the USA, range from 1600$ to 16,985$ per HIV reactive test in clinical and non-clinical settings). This result was transversal to several European cities, highlighting that there is a common CBVCT model, the cost of which is comparable regardless of the epidemiological context and prices. The CBVCT services represent an effective and “worth it” experience, to be continued and expanded in future public health strategies towards HIV.  相似文献   
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