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11.
Chromium (Cr) and nickel (Ni) are widely used industrial chemicals. Welders in India are inclined to possible occupational Cr and Ni exposure. The carcinogenic potential of metals is a major issue in defining human health risk from exposure. Hence, in the present investigation, 102 welders and an equal number of control subjects were monitored for DNA damage in blood leucocytes utilizing the Comet assay. The two groups had similar mean ages and smoking prevalences. A few subjects were randomly selected for estimation of Cr and Ni content in whole blood by inductively coupled plasma mass spectrometry. The Comet assay was carried out to quantify basal DNA damage. The mean comet tail length was used to measure DNA damage. Welders had higher Cr and Ni content when compared with controls (Cr, 151.65 versus 17.86 micro g/l; Ni 132.39 versus 16.91 micro g/l; P < 0.001). The results indicated that the welders had a larger mean comet tail length than that of the controls (mean +/- SD, 23.05 +/- 3.86 versus 8.94 +/- 3.16; P < 0.001). In addition, the micronucleus test on buccal epithelial cells was carried out in a few randomly selected subjects. Welders showed a significant increase in micronucleated cells compared with controls (1.30 versus 0.32; P < 0.001). Analysis of variance revealed that occupational exposure (P < 0.05) had a significant effect on DNA mean tail length, whereas smoking and age had no significant effect on DNA damage. The current study suggested that chronic occupational exposure to Cr and Ni during welding could lead to increased levels of DNA damage.  相似文献   
12.
We have previously demonstrated that Mycobacterium bovis BCG-specific immunoglobulin G antibodies in lymphocyte secretions (ALS) can be employed as a marker for active tuberculosis (TB). We aimed to determine whether the ALS method allows detection of subclinical TB infection in asymptomatic individuals. A prospective study of family contacts (FCs) of patients with active TB and healthy controls was performed. Thirteen of 42 FCs had high ALS responses, including 6 FCs who subsequently developed active TB. No correlation was observed between the tuberculin skin test and the ALS responses in the FCs (r = 0.1, P = 0.23). Among patients with active TB, BCG-specific ALS responses steadily declined from the time of diagnosis through 6 months following antimycobacterial chemotherapy (P = 0.001). The ALS assay enabled detection of infection in exposed symptom-free contacts, who are at greater risk for developing active TB. The method may also allow discrimination between effective treatment of active infection and suboptimal response to therapy.  相似文献   
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The role of survivin that regulates the biological behavior of non-small-cell lung carcinoma (NSCLC) is still controversial. We aimed to investigate survivin expression in NSCLC and to define any correlation with expressions of p53, bcl-2, bax, apoptotic index (AI), tumor cell proliferation, clinicopathologic variables, and overall survival. Tumors of 63 patients with NSCLC were examined for expressions of survivin, p53, bcl-2, bax, and Ki-67 by immunohistochemistry. AI was also evaluated. Results for each antibody were correlated with each other, and with clinicopathologic variables including age, sex, histologic subtype, TNM (T: primary tumor, N: regional lymph node metastasis, M: distant metastasis) stage, lymph node status, smoking history, and prognosis. Nuclear survivin expression was inversely correlated with p53 expression (P = 0.04, r = - 0.367), and tumor stage (P = 0.03, r = - 0.273), and positively correlated with tumor cell proliferation (P = 0.009, r = 0.329). Cytoplasmic survivin expression positively correlated with smoking history (P = 0.02, r = 0.282). Survivin/bax ratio was inversely correlated with AI (r: - 0.004). By Kaplan-Meier analysis, TNM stage (P < or = 0.001), lymph node metastasis (P = 0.04), and Ki-67 index (P < or = 0.001) were associated with survival, whereas survivin was not. In multivariate analysis, only TNM stage was an independent predictor. Although survivin and other apoptosis-related protein expressions fail to predict the clinical outcome, the present findings suggest that survivin is involved in tumor cell apoptosis and proliferation and may play a role in critical steps of cancer progression in NSCLC.  相似文献   
14.
The aim of the study was to investigate the efficiency of ram seminal plasma and fetal calf serum on freezing of buck semen. Twenty ejaculates were collected using an electro-ejaculator and split into six groups. While FCS additive was not used in A1, A2 and A3 groups, 10% FCS was added to B1, B2 and B3 groups. These groups were then edited according to whether the buck or ram SP was involved. The design of the groups was done as follows: Group A1 (control 1), group A2 without buck SP, group A3 containing ram SP instead of buck SP. Groups B1 (control 2), B2 and B3 were the FCS added forms of these groups. Progressive sperm motility percentages in Group A1 and Group B2 were found to be higher when compared to the lowest Group B3. There were no significant differences between the groups in neither the levels of reactive oxygen species nor the enzyme and glutathione activities. In conclusion, the lack of statistical difference between the groups suggested that despite the supplements used but only when the buck spermatozoa structure was healthy, the cell could preserve acrosome, DNA and the integrity of membrane.  相似文献   
15.
BACKGROUND AND OBJECTIVE: To study the predictors of success in macular hole surgery. PATIENTS AND METHODS: Twenty-two eyes of 21 patients underwent macular hole surgery. The hole closure rate and the visual improvement were studied based on the preoperative visual acuity, stage and duration of the macular hole, the type of intravitreal tamponade used, and internal limiting membrane peeling. The internal limiting membrane was peeled only when it was clinically prominent. RESULTS: Macular holes were closed in 19 of the 22 eyes and visual improvement of 2 lines or more was achieved in 17 eyes. Preoperative visual acuity, duration of the macular hole, type of intraocular tamponade used, and internal limiting membrane peeling did not affect the outcome. A final visual acuity of 20/70 or better was more common after surgery for stage 2 holes (P = .019). CONCLUSION: The best predictor of outcome was the stage of the hole, with best results obtained in stage 2 holes.  相似文献   
16.
The technical name for a surgical sponge left in the body of a patient is inadvertent “gossypiboma.” The word is derived from the Latin word Gossypium for cotton and from the Kiswahili word boma for “place of concealment.” These retained sponges were first seen as “textilomas,” but were renamed “gossypiboma” in 1978. The first case was reported by Wilson in 1884. These are rarely are retrieved in the literature, because of legal complications. A higher incidence of retained laparotomy sponges has been reported in association with gynecological procedures. We report a case of gossypiboma in the 38th week of pregnancy that imitated an ovary neoplasm.  相似文献   
17.
PURPOSE: The objective of this study was to determine whether the addition of trastuzumab to chemotherapy in the neoadjuvant setting could increase pathologic complete response (pCR) rate in patients with human epidermal growth factor receptor 2 (HER2) -positive disease. PATIENTS AND METHODS: Forty-two patients with HER2-positive disease with operable breast cancer were randomly assigned to either four cycles of paclitaxel followed by four cycles of fluorouracil, epirubicin, and cyclophosphamide or to the same chemotherapy with simultaneous weekly trastuzumab for 24 weeks. The primary objective was to demonstrate a 20% improvement in pCR (assumed 21% to 41%) with the addition of trastuzumab to chemotherapy. The planned sample size was 164 patients. RESULTS: Prognostic factors were similar in the two groups. After 34 patients had completed therapy, the trial's Data Monitoring Committee stopped the trial because of superiority of trastuzumab plus chemotherapy. pCR rates were 25% and 66.7% for chemotherapy (n = 16) and trastuzumab plus chemotherapy (n = 18), respectively (P = .02). The decision was based on the calculation that, if study continued to 164 patients, there was a 95% probability that trastuzumab plus chemotherapy would be superior. Of the 42 randomized patients, 26% in the chemotherapy arm achieved pCR compared with 65.2% in the trastuzumab plus chemotherapy arm (P = .016). The safety of this approach is not established, although no clinical congestive heart failure was observed. A more than 10% decrease in the cardiac ejection fraction was observed in five and seven patients in the chemotherapy and trastuzumab plus chemotherapy arms, respectively. CONCLUSION: Despite the small sample size, these data indicate that adding trastuzumab to chemotherapy, as used in this trial, significantly increased pCR without clinical congestive heart failure.  相似文献   
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Asthma is a significant global public health issue. Severe asthma exacerbations can be triggered by environmental factors and require medical care from health services. Although it is known that fungal exposure may lead to allergic sensitization, little is understood about its impact on asthma exacerbations. This review aims to examine whether outdoor fungi play a significant role in child asthma exacerbations. Systematic search of seven electronic databases and hand searching for peer‐reviewed studies published in English, up to 31 August 2013. Inclusion criteria were study population aged <18 yr, diagnosis of asthma, attended a health service; outdoor fungi exposure was reported. Quality and risk of bias assessments were conducted. Due to significant heterogeneity, meta‐analysis was not conducted. Of the 1896 articles found, 15 were eligible. Findings were not consistent, possibly due to methodological variations in exposure classifications, statistical methods and inclusion of confounders. Cross‐sectional studies found no or weak associations. All but one time series studies indicated an association that varied between fungal species. Increasing evidence indicates that asthmatic children are susceptible to asthma exacerbations when exposed to outdoor fungal spores. There is limited understanding of the contributions of different fungal species. Research is needed to investigate interactions of outdoor fungi with pollen, air pollutants and respiratory viruses.  相似文献   
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