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91.
This study was performed to investigate the heavy metal concentrations in muscle, liver, gill and intestine of six ray species from ?skenderun Bay. The present study is the first for rays in ?skenderun Bay, providing valuable preliminary information about heavy metal contents in different tissues of the examined ray species from the bay, and indirectly, indicating the environmental contamination of ?skenderun Bay. Heavy metal levels in intestines were generally higher than those in other tissues for all species. Metal levels in ray muscle tissue were below the international maximum allowable levels for fish and fishery products, as well as Turkish national guidelines, with the exception of the highest value for Cd in Dasyatis pastinaca.  相似文献   
92.
Catechol-containing imidazolium (four) and benzimidazolium chlorides (eight) were synthesized to evaluate their antimicrobial properties. All the compounds were fully characterized using 1H and 13C nuclear magnetic resonance, liquid chromatography–mass spectrometry, infrared spectroscopic methods, and elemental analyses. Antimicrobial activities of the compounds were tested against the bacteria Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumoniae, Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Enterococcus faecalis, and the fungal strains Candida albicans and Candida glabrata, and promising results were achieved. The two most important benzyl-substituted benzimidazolium chlorides, 3l and 3k , showed comparable activity to vancomycin against MRSA.  相似文献   
93.
To understand antioxidant activity and the role played by melatonin, we have designed and tested several new compounds. We present the results in terms of structure-activity relationships, focusing on the lack of the methoxy group and the influence of the amide side chain. Antioxidant activity of melatonin and some new melatonin analogue indole derivatives were investigated, using lipid peroxidation and superoxide anion radical scavenger activity assays, in rat liver tissue homogenate. Most of the compounds were found to be very potent inhibitors of malondialdehyde (MDA) formation at 10−3M. Inhibition rates ranged from 75-44 %. However, no significant inhibitory effect was obtained on superoxide anion formation. Consequently, it can be concluded that these compounds exhibit important LP activity compared to melatonin.  相似文献   
94.
The aim of this study was to investigate the possible protective role of lycopene on cisplatin (CP)-induced spermiotoxicity using quantitative, biochemical and histopathological approaches. Adult male Sprague-Dawley rats were randomly divided into four groups. The control group received physiological saline; animals in cisplatin group received only cisplatin; pre-treatment group received a 10-day of lycopene before administration of cisplatin while animals in post-treatment group received a 5-day of lycopene following administration of cisplatin. Cisplatin (7 mg kg(-1)) was intraperitoneally (i.p.) injected as a single dose and lycopene (4 mg kg(-1)) was administered by gavage in corn oil. Traits of reproductive organs; sperm characteristics, testicular histological findings, plasma testosterone levels and the testicular tissue oxidative status were determined. Administration of cisplatin to rats decreased sperm concentration (p < 0.05) and sperm motility (p < 0.001), increased total abnormal sperm rates (p < 0.05) as compared with the control group. While a marked normalization was achieved only in sperm concentration with lycopene in pre-treatment group, significant normalizations were achieved in the sperm concentration, sperm motility, total abnormal sperm rates in post-treatment group. No significant differences in levels of testosterone were observed among all groups. An increase in testes malondialdehyde concentrations (p < 0.05) and glutathione peroxidase activities (p < 0.001) were detected while significant decreases in glutathione levels (p < 0.001) in cisplatin alone group when compared to control group. While pre-treatment with lycopene restoring only malondialdehyde concentrations, its post-treatment caused normalization in both malondialdehyde and glutathione levels when compared with the cisplatin alone group. On the other hand, significant increases were determined in GSH-Px activities in all experimental groups when compared with the control group. Although the mechanism is not clear, the results from this experimental study suggest that the lycopene have a possible protective effect against cisplatin-induced spermiotoxicity, effect of giving lycopene after cisplatin being superior to the giving it before cisplatin.  相似文献   
95.
PURPOSE: The discovery of new ovarian cancer biomarkers that are suitable for early disease diagnosis and prognosis may ultimately lead to improved patient management and outcomes. PATIENTS AND METHODS: We measured, by immunoassay, human kallikrein 6 (hK6) concentration in serum of 97 apparently healthy women, 141 women with benign abdominal diseases, and 146 women with histologically proven primary ovarian carcinoma. We then calculated the diagnostic sensitivity and specificity of this test and examined the association of serum hK6 concentration with various clinicopathologic variables and patient survival. RESULTS: Serum hK6 concentration between normal and benign disease patients was not different (mean, 2.9 and 3.1 micro g/L, respectively). However, hK6 in presurgical serum of ovarian cancer patients was highly elevated (mean, 6.8 micro g/L; P <.001). Serum hK6 decreased after surgery (to a mean of 3.9 micro g/L) in 68% of patients. The diagnostic sensitivity of serum hK6 at 90% and 95% specificity is 52% and 47%, respectively, in the whole patient population. For early stage disease (stage I or II), sensitivity is approximately 21% to 26%. When combined with CA-125, at 90% specificity, sensitivity increases to 72% (for all patients) and to 42% in stage I or II disease. Serum hK6 concentration correlates moderately with CA-125 and is higher in patients with late-stage, higher-grade disease and in patients with serous histotype. Preoperative serum hK6 concentration is a powerful predictor of disease-free and overall survival in both univariate and multivariate analyses. CONCLUSIONS: Serum hK6 concentration seems to be a new biomarker for ovarian carcinoma and may have value for disease diagnosis and prognosis.  相似文献   
96.
Enterocutaneous fistula (EF) in newborns and prematures is a well-recognized complication after necrotizing enterocolitis and other abdominal surgical procedures. Conservative management consists of bowel rest, antibiotics, wound care, and the administration of drugs that either reduce gastrointestinal motility or secretions. Octreotide decreases gastrointestinal secretions, inhibits or blocks the effects of gastrointestinal hormones, diminishes gut motility and thus reduces the flow through the fistula. We used octreotide and were able to report successful spontaneous closure of a fistula in our 2 neonatal patients, one a premature neonate with necrotizing enterocolitis (NEC) and the other with meconium peritonitis.  相似文献   
97.
HYPOTHESIS: Glutathione and glutathione-related antioxidant enzymes are involved in the metabolism and detoxification of cytotoxic and carcinogenic compounds as well as reactive oxygen species. Reactive oxygen species generation occurs in prolonged relative hypoperfusion conditions such as in aging. The etiology of presbycusis is much less certain; however, a complex genetic cause is most likely. The effect of aging shows a wide interindividual range; we aimed to investigate whether profiles of (glutathione S-transferase (GST) M1, T1 and P1 genotypes may be associated with the risk of age-related hearing loss. PATIENTS AND METHODS: We examined 68 adults with presbycusis and 69 healthy controls. DNA was extracted from whole blood, and the GSTM1, GSTT1 and GSTP1 polymorphisms were determined using a real-time polymerase chain reaction and fluorescence resonance energy transfer with a Light-Cycler Instrument. Associations between specific genotypes and the development of presbycusis were examined by use of logistic regression analyses to calculate odds ratios and 95% confidence intervals. RESULTS: Gene polymorphisms at GSTM1, GSTT1, and GSTP1 in subjects with presbycusis were not significantly different than in the controls (p > 0.05). Also, the combinations of different GSTM1, GSTT1, and GSTP1 genotypes were not an increased risk of presbycusis (p > 0.05). CONCLUSION: We could not demonstrate any significant association between the GSTM1, GSTT1, and GSTP1 polymorphism and age-related hearing loss in this population. This may be because of our sample size, and further studies need to investigate the exact role of GST gene polymorphisms in the etiopathogenesis of the presbycusis.  相似文献   
98.
Clinical and Experimental Medicine - The TIRADS is a scoring system used for the selection of nodules for FNA and classification of the risk of malignancy based on ultrasound characteristics. The...  相似文献   
99.

Purpose

Renal cell carcinoma (RCC) accounts for approximately 80% of the primary renal cancers, and current treatment strategies are not sufficient to provide a certain solution. Since there are not many treatment options, interest in discovery of alternative drugs has increased.

Methods

In the current study, anticancer activity of a novel heterodinuclear Cu(II)–Mn(II) complex (Schiff base—SB) in combination with poly(ethylene oxide) and poly(propylene oxide) block copolymer (pluronic) P85 was tested against RCC. Cell viability, apoptosis and gene expression analysis were conducted in vitro by using Renca cells.

Results

The results revealed that the SB–P85 combination decreased cell proliferation by increasing the apoptotic gene expressions and apoptosis. Renca-injected BALB/c mice were used to mimic early stage of RCC model. Treatment with SB–P85 combination suppressed tumor formation and growth compared to baseline.

Conclusion

Overall, SB–P85 showed promising anticancer activity against RCC in vitro and in vivo.
  相似文献   
100.
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