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11.
This study was aimed to investigate the reproductive health in adult male rats exposed to di‐n‐butyl phthalate (DBP) during embryonic development. Pregnant rats were injected with DBP and F1 male rats were weaned and on postnatal day 100, used for mating with normal cycling females to assess reproductive performance. After completion of cohabitation period, rats were analyzed for other reproductive end points. Transplacental exposure to DBP significantly decreased fertility in adult male rats. Prenatal exposure to DBP significantly decreased sperm density, number of motile sperms, viable sperms, and hypoosmotic swelling tail coiled sperms with an increase in morphological abnormalities in sperms. Testicular steroidogenic enzyme activity levels and serum testosterone levels were significantly decreased in rats exposed to DBP during embryonic development. In conclusion, transplacental exposure to DBP impairs male reproductive performance by decreasing steroidogenesis and spermatogenesis. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 534–544, 2014.  相似文献   
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13.
This paper presents the research results of one of the main technological parameters of belt grinding, i.e., the cutting speed while machining corrosion- and heat-resistant, structural carbon and structural alloy steels, aluminum, and heat-resistant nickel alloys. Experimental and analytical methods are used to establish the dependence of the output parameters of surface belt grinding on the cutting speed and tool characteristics. An analytical model, considering the physical and mechanical properties of the grinding belt (strength depending on the base and bond; the thermal conductivity; the type of grinding operation) and the machined material, is created to determine the belt grinding speed. The output parameters, such as the arithmetic mean of the surface roughness (Ra) and the material removal rate (MRR) during the belt grinding of steels, heat-resistant and light alloys, have been studied. Based on the empirical dependencies of the belt grinding parameters, the model was developed for the selection and setting of the cutting speed of belt grinding for the aforementioned alloys, taking into account the type of operation, the type of the machined material, and the main characteristics of the sanding belt.  相似文献   
14.
This study investigated the effect of 10 or 100 mg/kg/day quercetin on the uterus of ovariectomized adult female rats receiving sex-steroid replacement regime mimicking changes in hormonal profiles during the reproductive cycle. Following seven days of treatment with estrogen and progesterone with or without quercetin, uteri were harvested for histological and proliferative cell nuclear antigen (PCNA) protein and mRNA expression and PCNA protein distribution analyses. Our findings indicated that co-administration of 10 mg/kg/day quercetin with estrogen and progesterone caused a significant decrease in the size of uterine lumen and epithelial heights with lower PCNA protein and mRNA expression as compared to estrogen plus progesterone-only treatment (P < 0.05). Concomitant treatment with estrogen and progesterone with 100 mg/kg/day quercetin resulted in a marked increase in the number of glands with increased PCNA protein and mRNA expression. Significantly higher PCNA distribution was observed in the stroma and glands as compared to estrogen plus progesterone-only treatment (P < 0.05). In conclusion, at 10 mg/kg/day, quercetin affects uterine morphology but not proliferation, however at 100 mg/kg/day, quercetin induced significant stromal and glandular proliferation which could predispose the uterus towards neoplastic development.  相似文献   
15.
Accumulating evidence suggests that certain features of hepatitis C virus (HCV), especially its high genetic variability, might be responsible for the low efficiency of anti-HCV treatment. Here, we present a bioinformatic analysis of HCV-1a populations isolated from 23 children with chronic hepatitis C (CHC) subjected to interferon–ribavirin therapy. The structures of the viral quasispecies were established based on a 132-amino-acid sequence derived from E1/E2 protein, including hypervariable region 1 (HVR1). Two types of HCV populations were identified. The first type, found in non-responders, contained a small number of closely related variants. The second type, characteristic for sustained responders, was composed of a large number of distantly associated equal-rank variants. Comparison of 445 HVR1 sequences showed that a significant number of variants present in non-responding patients are closely related, suggesting that certain, still unidentified properties of the pathogen may be key factors determining the result of CHC treatment.  相似文献   
16.
BACKGROUND: Our aim was to explore the activity and feasibility of gemcitabine plus cisplatin as induction chemotherapy in patients with Stage IIIA N(2) and selected IIIB non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: From September 1997 to July 2000, 70 chemonaive patients with Stage III NSCLC, median age of 64 years, World Health Organization performance status 0, 1, or 2, and the ability to tolerate a pneumonectomy entered the study and received gemcitabine 1250 mg/m(2) on days 1 and 8 and cisplatin 70 mg/m(2) on day 2 every 3 weeks. After three cycles of induction chemotherapy, patients underwent resection or radiotherapy. RESULTS: Responses were seen in 40 of the 69 assessable patients, for an intent-to treat overall response rate of 57.1% (95% confidence interval, 45-62%), with 4.2% complete response. Response rates were 68 and 35% in patients with Stage IIIA and IIIB disease, respectively. The overall pathological CR rate after induction chemotherapy was 3%, with an overall pathological downstaging rate of 20%. Median survival for all patients was 14.5 months, with an estimated 1-year survival rate of 67% (95% CI, 54.3-79.5%). The estimated time to treatment failure was 12.6 months. Grade 3/4 thrombocytopenia was the main hematologic toxicity, occurring in 26% of patients, but was not associated with life-threatening bleeding. Febrile neutropenia was rare and other severe non-hematologic toxicities were uncommon. CONCLUSIONS: The 3-week schedule of gemcitabine plus cisplatin is highly active as induction chemotherapy in Stage IIIA N(2) unresectable NSCLC. This suggests a need for a multimodality approach upfront, such as concurrent chemoradiation therapy, particularly in patients with Stage IIIB disease.  相似文献   
17.

Background  

We carried out a three months follow-up study on the efficacy of metadoxine in a cohort of alcoholics admitted to the Alcohol misuse Long-term Treatment (ALT) Unit – University of Pisa (Italy). We analyzed the clinical data, psychometric tests and blood tests of 160 alcoholics on admission and after 3 months of treatment. We compared 58 pts treated with metadoxine (MET) with 102 pts who did not receive (NULL) any drug as an adjunct to the psycho-educational interventions provided by the ALT Unit.  相似文献   
18.
19.

Background

The association between intravascular ultrasound (IVUS) signs of plaque instability and plasma levels of biomarkers was determined in patients with unstable angina and non-ST-segment elevation myocardial infarction (UA/NSTEMI).

Methods

Fifty-two patients underwent coronary angiography and IVUS 8 ± 5 hours after the onset of chest pain. IVUS analysis included plaque morphology, disruption, thrombi and eccentricity, lumen, external elastic membrane, and plaque plus media areas of culprit lesion and reference segments and arterial remodeling. Plasma levels of the thrombin activation system (thrombin-antithrombin complex [TAT], tissue factor pathway inhibitor [TFPI], and prothrombin fragments 1+2 [F1+2]) and plasmin activation system (tissue and urokinase-type plasminogen activator [t-PA and u-PA], plasminogen activator inhibitor-1 [PAI-1], and D-dimer) were measured with enzyme-linked immunosorbent assay kits before angiography.

Results

Elevated levels of TAT (7.2 ± 6.0 μg/L), F1+2 (1.8 ± 1.0 nmol/L), TFPI (179.1 ± 131.0 ng/mL), PAI-1 (95.4 ± 54.6 ng/mL), t-PA (10.6 ± 8.8 ng/mL), and u-PA (2.6 ± 0.9 ng/mL) were found in patients with UA/NSTEMI. The serum levels of D-dimer (40.0 ± 39.5 ng/mL) remained in reference range. Expansive and constrictive remodeling were found in 18 (35%) and 12 (23%) patients, respectively. Expansive remodeling of the culprit lesion was associated with significantly higher plasma levels of PAI-1 (121.6 ± 55.0 vs 87.7 ± 61.5 and 77.4 ± 42.8 ng/ml, P = .039), and u-PA (3.0 ± 1.2 vs 2.2 ± 0.5 and 2.5 ± 0.7 ng/mL, P = .026) as compared with constrictive and neutral remodeling. Increased plasma levels of u-PA were associated with plaque rupture (3.0 ± 0.7 vs 2.5 ± 0.9 ng/mL, P = .062). Plasma levels of PAI-1 and u-PA correlated positively with plaque plus media (P = .0297 and P = .0093) and external elastic membrane areas (P = .010 and P = .0002).

Conclusions

Elevated levels of biomarkers of plasmin activation system are associated with signs of plaque instability of culprit lesion in UA/NSTEMI and might therefore serve as non-invasive determinants of the population that is at high risk for subsequent adverse events.  相似文献   
20.
Heme oxygenase 1 (HO-1) is involved in the generation of the endogenous anti-oxidant bilirubin which exerts beneficial effects against arteriosclerosis. A (GT) repeat polymorphism in the HO-1 promoter region modulates HO-1 expression in response to oxidative stress. Recently, this polymorphism has been reported to protect from coronary artery disease in Orientals. We intended to confirm this observation in Caucasians. We studied 649 individuals with myocardial infarction (n=258), stable coronary artery disease (n=180) and controls without coronary artery disease (n=211). Carriers of short alleles (<25 repeats) had higher bilirubin levels (median 0.66 mg/dL, IQR 0.49 to 0.91) compared to non-carriers (median 0.61 mg/dL, IQR 0.45 to 0.82; p=0.03) and a more favourable lipid profile (HDL median 47 mg/dL, IQR 40 to 50 vs. median 45, IQR 37 to 55, p=0.01; triglycerides median 118 mg/dL, IQR 87 to 174 vs. median 132, IQR 97 to 191, p=0.03). However, no significant differences of the genotype distribution were observed between the three groups in this Caucasian study population (p=0.94). Although potentially beneficial effects of the short HO-1 allele on lipid profile and serum bilirubin were observed, in contrast to Orientals, the HO-1 genotype was not associated with coronary artery disease in Caucasians.  相似文献   
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