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排序方式: 共有3726条查询结果,搜索用时 15 毫秒
1.
Fahad Ali Rahul Smita Jyoti Ambreen Fatima Saba Khanam Falaq Naz Yasir Hasan Siddique 《Scientia pharmaceutica》2016,84(2):361-377
The present investigation was aimed at studying the possible role of curcumin against N-nitrosodiethylamine (NDEA)-induced toxicity in albino rats. Administration of NDEA to rats at a concentration of 0.1 mg/ml in drinking water ad libitum for 21 days produced toxicity in them, which was evident from histopathological changes in the rat livers, and increased levels of blood serum enzyme markers, i.e. aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase. In addition, the levels of oxidative stress markers like lipid peroxidation (LPO), protein carbonyl (PCC), and glutathione-S-transferase (GST) activity were elevated and the total glutathione (GSH) content was reduced in the livers. The administration of curcumin to rats at concentrations of 10, 20, and 40 mg/ml in drinking water along with 0.1 mg/ml of NDEA for 21 days effectively suppressed NDEA-induced toxicity and also resulted in a dose-dependent reduction in the levels of blood serum enzyme markers (AST, ALT, ALP, and LDH). Moreover, LPO, PCC, and GST activity were reduced and the GSH level was increased upon the administration of curcumin along with NDEA. The results obtained for the comet assay in rat hepatocytes and blood lymphocytes showed a significant dose-dependent decrease in the mean tail length. The micronucleus assay performed on rat hepatocytes also showed a dose-dependent reduction in the frequency of micronucleated cells along with curcumin administration. These results suggest that curcumin has a protective role against NDEA-induced toxicity in albino rats. 相似文献
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Shakil Saba Muhammad Sajid Hamid Akash Kanwal Rehman Uzma Saleem Fareeha Fiayyaz Tanvir Ahmad 《Clinical and experimental pharmacology & physiology》2020,47(10):1682-1691
Arsenic (As) and cadmium (Cd) have recently emerged as major health concerns owing to their strong association with diabetes mellitus (DM). We aimed to investigate the heavy metals exposure towards incidence of DM at various enzymatic and hormonal levels. Additionally, association of As and Cd with Zinc (Zn, essential metal) was also evaluated. Spot urine samples were collected to assess As, Cd and Zn through ICP-OES. Serum was analyzed by assay method for fasting blood glucose, liver and renal function biomarkers. ELISA was performed to investigate the impact of heavy metals on HbA1c, α-amylase, DPP-IV, IGF-1, leptin, GSH, MDA, SOD, HDL, FFA, TG and interleukin (IL)-6. Association of heavy metals with DM was measured by odds ratio (OR) and level of significance was assessed by Chi-squared test. Unpaired student's t-test was used to compare DM-associated risk factors in heavy metals-exposed and unexposed participants. As and Cd were detectable in 75.4% and 83% participants with mean concentration of 75.5 ppb and 54.5 ppb, respectively. For As exposure, OR in the third quartile was maximum ie 1.34 (95% CI, 0.80 to 2.23), however the result was not statistically significant (P > .05). For Cd exposure, OR in the fourth quartile was considerably high, 1.62 (95% CI, 1.00 to 2.61), with a significant probability value (P < .05). Urinary Cd was negatively associated with Zn. As and Cd exposure increases the incidence of DM in the general population. Impaired hormonal and enzymatic levels in diabetic and non-diabetic exposed participants reflect the multiple organ damage by heavy metal exposure. 相似文献
4.
A. Giacometti O. Cirioni G. Greganti A. Fineo R. Ghiselli M. Del Prete F. Mocchegiani B. Fileni F. Caselli E. Petrelli V. Saba G. Scalise 《European journal of clinical microbiology & infectious diseases》2002,21(7):553-556
The in vitro activities of povidone iodine, potassium peroxymonosulfate, and dimethyldidecylammonium chloride were investigated
against 379 nosocomial isolates of Staphylococcus aureus and Pseudomonas aeruginosa responsible for surgical wound infections in patients operated on between July 1995 and June 2001. Overall, the isolates
were inhibited by the antiseptics at concentrations below those used routinely. In spite of increasing resistance to the various
antibiotics used to treat surgical wound infections, no significant variation in the susceptibility to antiseptics was demonstrated
during this 6-year study.
Electronic Publication 相似文献
5.
We report a case of multiple endocrine neoplasia type I and hypernephroma. Parathyroid hyperplasia, adrenocortical hyperplasia, a nodular goiter, multiple lipomas, a chromophobe adenoma of the pituitary and hypernephroma had all been diagnosed previously. All but the last are features consistent with the diagnosis of multiple endocrine neoplasia type I (Wermer's syndrome). The association of multiple endocrine neoplasia type I and hypernephroma may represent a new manifestation of this pleiotropic syndrome. 相似文献
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Septic surgical patients often require fluid administration to maintain cardiovascular stability due, in part, to the sepsis-induced increase in vascular permeability and associated plasma volume depletion. Plasma fibronectin deficiency exists in such septic patients. We determined if maintenance of fibronectin levels by administration of fibronectin-rich human plasma cryoprecipitate would lower the resuscitative fluid volume needed for support of arterial pressure in septic postoperative sheep which were experimentally depleted of plasma fibronectin. Following a 2-hr postoperative baseline period, denatured collagen (gelatin, 8.7 mg/kg), which has a high affinity for fibronectin, was infused into both control and experimental sheep in order to acutely deplete plasma fibronectin. Sheep were then challenged both intraperitoneally and intravenously with live Pseudomonas (5 x 10(10) bacteria IP; 5 x 10(9) bacteria IV). Experimentals were given fresh plasma cryoprecipitate intravenously at a dose of 4 units bolus, followed by 3 units/hr for 5 hr. Controls received plasma cryoprecipitate selectively depleted of fibronectin by affinity chromatography. Bacterial challenge rapidly resulted in severe systemic hypotension. Ringer's lactate was infused intravenously into both groups at a rate sufficient to maintain a systemic arterial pressure of approximately 50 mm Hg with a maximum pulmonary artery wedge pressure of 15-18 mm Hg. Its rate of infusion was periodically adjusted to maintain this hemodynamic status. Comparison was made of the volume of Ringer's lactate required to maintain an arterial pressure of 50 mm Hg in both groups. Net fluid requirement was significantly (p less than 0.05) less in postoperative septic sheep (47.4 +/- 6.2 mg/kg/hr) treated with fibronectin-rich cryoprecipitate compared to the fluid requirement (71.7 +/- 4.7 mg/kg/hr) for postoperative septic sheep receiving fibronectin-deficient cryoprecipitate. Thus elevation of plasma fibronectin concentration lowers the fluid requirements needed for hemodynamic support in postoperative Gram-negative sepsis. 相似文献
8.
Lutz Fritsche Gunilla Einecke Franca Fleiner Duska Dragun Hans-Hellmut Neumayer Klemens Budde 《American journal of transplantation》2004,4(5):738-743
The reporting quality of publications of clinical trials can affect the quality of clinical decision-making. We systematically assessed the quality of publications of large multicenter trials evaluating immunosuppressive regimens in de novo kidney transplantation. Study quality, reporting quality and accessibility of the results of 63 publications were assessed independently by three blinded investigators using an instrument combining the Jadad scale with a list of reporting quality items. Study quality was rated with an average of only 2.3 (range 1-5) on the Jadad scale. Unblinded studies were reported in 68.3% of publications and follow-up longer than 12 months was reported for only 13 out of 50 studies. The reviewed publications fulfilled an average of 69.1% of the reporting quality criteria. Fifty-four percent of publications did not report both treated and biopsy-proven rejections. Whether reported graft survival was censored for death could not be determined for 27% of publications. Only a few publications gave confidence intervals (CIs) or stated whether additional analyses were pre-specified. Even the largest trials of immunosuppression in kidney transplantation show considerable quality deficits in their design and publication. Additional efforts are required of investigators, editors and sponsors to achieve maximum study and reporting quality. 相似文献
9.
Biomarkers have long held out the promise that malignancies might be diagnosed early and that patients could be monitored more confidently during their clinical course to more reliably predict recurrence and the effect of therapy. Reliable tumor markers have been described for colon carcinoma, hepatomas, and other tumors, but no reliable marker has been identified to monitor the course of malignant melanoma. Recently, the plasma level of lipid-bound sialic acid (LASA-P) has been described as reflecting an alteration in the surface membrane of cancer cells. An attempt was made to correlate the LASA-P level, along with the serum level of neuron-specific enolase, a glycolytic enzyme specific to cells of neuroectoderm origin including melanocytes, with clinical disease activity with a follow-up to at least 2 years. Two hundred seventy patients had blood samples drawn at various times during their clinical course for assay of LASA-P and neuron-specific enolase. Eighty of the patients (30%) sampled developed a recurrence sometime during their clinical course, whereas another 10 patients had active disease noted at diagnosis with evaluative tumor markers. The sensitivity and specificity of neuron-specific enolase was 27% and 77%, respectively, and cannot be recommended as a marker for melanoma. LASA-P showed a sensitivity of 65%, with 55 patients recurring and having active disease with abnormally high markers and 35 patients recurring or having active disease with normal markers. Specificity of the LASA-P test was 76%. When recurrence was associated with elevated LASA-P levels, the elevated level preceded recurrence by a median of 9.3 months. LASA-P may be a useful marker to follow patients with malignant melanoma. 相似文献
10.
Franca Formelli Loredana Cleris Roberto Carsana 《Cancer chemotherapy and pharmacology》1988,21(4):329-336
Summary The effect of the combined administration of verapamil (i.p. twice daily) and doxorubicin (i.v once weekly) was tested in mice bearing the following: (a) a tumor with induced resistance to doxorubicin (B16VDXR melanoma line); (b) a tumor inherently resistant (MXT mammary carcinoma); and (c) four solid tumors sensitive to doxorubicin (B16 melanoma, B16V melanoma line, M5076 reticulum cell sarcoma, and Lewis lung carcinoma). Verapamil, given according to this treatment schedule, reached peak plasma concentrations of 3 M. Such treatment did not enhance doxorubicin activity on either inherently or induced resistant tumors, whereas it significantly enhanced doxorubicin growth inhibition in all the sensitive tumors except the Lewis lung carcinoma. Doxorubicin pharmacokinetics after administration of the drug alone and in combination with verapamil was analyzed after the first and repeated treatments in animals bearing B16 melanoma or its resistant subline B16VDXR. The resistance of the B16VDXR line was associated with the ability of the tumor to retain less doxorubicin (AUC=83 g h/g) than the sensitive tumor B16 (AUC=204 g h/g) in spite of similar initial levels. The potentiating effect of doxorubicin activity by, verapamil in B16 melanoma was not associated with increased doxorubicin levels or retention in the tumor, nor were differences in doxorubicin levels or retention found in the B16VDXR line. The combined treatment did not modify doxorubicin pharmacokinetics in plasma, heart, or spleen. These studies suggest that verapamil in vivo is ineffective in potentiating doxorubicin activity in tumors against which doxorubicin is inactive, that sensitive tumors are heterogeneous in their sensitivity to modulation by verapamil, and that this effect is not associated with modification of doxorubicin pharmacokinetics.This work was supported by grant no. 84.00855.44 of the Finalized Project Oncologia from the Consiglio Nazionale delle Ricerche, Rome 相似文献