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A repetitive target sequences of Mycobacterium tuberculosis DNA was amplified by polymerase chain reaction (PCR) in a total of 301 clinical samples. Sputum, blood, pleural fluid, and bronchial lavage specimen were taken from clinically suspected causes of tuberculosis and processed for the diagnosis of tuberculosis using a simplified procedure of DNA extraction. PCR was positive in a total of 58 samples (58/301--19.3%). A significant number of smear and culture negative cases of tuberculosis were PCR positive (37/174--21.26%). This finding, combined with the absence of either false positive or false negative results reflects the greater usefulness of this technique.  相似文献   
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Purpose Prostate cancer is the second most common cancer that leads to death in elderly men. The risk of prostate cancer prevalence is often associated with the elevated level of insulin-like growth factor-I (IGF-I) and decreased level of IGF-binding protein 3 (IGFBP-3). Lycopene, a carotenoid, reduces the proliferation of cancer cells and induces apoptosis. Hence, higher intake of lycopene can be associated with the lower risk of prostate cancer. However, the mechanism of action of lycopene in the prevention of prostate cancer is still unclear. The present study was carried out to study the effects of lycopene on the components of IGF system and apoptosis in androgen-independent prostate cancer cells (PC-3 cells). Methods PC-3 cells were treated with various concentrations of lycopene, (20, 40 and 60 μM) for 24, 48, 72 and 96 h. IGF-I, IGFBP-3 and IGF-I receptor (IGF-IR) levels in lycopene-treated cells were evaluated. Annexin V and propidium iodide (PI) binding studies were done to assess apoptosis. Results PC-3 cells treated with lycopene showed a significant decrease in cell proliferation. Lycopene, at a dose of 40 μM, significantly increased the level of IGFBP-3. Lycopene-induced apoptosis was confirmed by annexin V and PI binding. Lycopene-induced DNA fragmentation was absent after 24 h treatment whereas the same was observed after 48 h treatment. There was a significant decrease in the IGF-IR expression after the cells were treated with lycopene and IGF-I. Conclusion The data obtained suggest that the components of the IGF system may act as a positive regulator of lycopene-induced apoptosis in PC-3 cells. Thus, the observed lycopene-induced biological effects and their associated mechanisms are encouraging and may lead to the development of a highly successful drug for the treatment of prostate cancer.  相似文献   
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Aim:Antithrombotic therapy with heparin plus antiplatelets reduces the rate of ischemic events in patients with coronary heart disease. Low molecular weight heparin has a more predictable anticoagulant effect than standard unfractionated heparin, is easier to administer, does not require monitoring and is associated with less ADRs. The purpose of the present study was to evaluate and compare the clinical and cost outcomes of Enoxaparin with a standard unfractionated heparin in patients with coronary heart disease.Results:Compared to unfractionated heparin group of patients, the average prothrombin time was significantly higher (P < 0.0001) whereas hypokalemia was significantly lower (P < 0.02) in enoxaparin group of patients. Even though recurrence of angina and ADRs such as bleeding, nausea, headache and sudden cough occurred less frequently in the enoxaparin group of patients compared to unfractionated heparin group of patients, the differences were not significant.Conclusions:Antithrombotic therapy with enoxaparin plus aspirin was safer and more effective than unfractionated heparin plus aspirin, in reducing the incidence of ischemic events in patients with unstable angina or myocardial infarction in the early phase.KEY WORDS: Anticoagulant, coronary heart disease, enoxaparin, safety, and efficacy, unfractionated heparin  相似文献   
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The aim of this study was to investigate the possible protective role of vitamins on PCB (Aroclor 1254)-induced spermiotoxicity using qualitative, quantitative and biochemical approaches. Adult male albino rats of Wistar strain were randomly divided into four groups, each group consists of six animals. The control group received corn oil, the second group of rats were administered Aroclor 1254 at a dose of 2 mg/kg bw/day intraperitoneally for 30 days. The third group of rats were treated with Aroclor 1254 along with alpha-tocopherol (50 mg/kg of bw/day) for 30 days, while the fourth group of rats were treated with Aroclor 1254 along with ascorbic acid (100 mg/kg bw/day) orally for 30 days. Twenty-four hours after the last treatment, control and experimental animals were killed by decapitation. Sperm was collected from the cauda epididymal region and its count and motility were detected. Sperm was sonicated and used for the estimation of reactive oxygen species (ROS) [hydroxyl radical (HO(*)) and hydrogen peroxide (H(2)O(2))], non-enzymic antioxidants [alpha-tocopherol, ascorbic acid and reduced glutathione (GSH)], activity of enzymic antioxidants [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) glutathione reductase (GR) and glutathione-S-transferase (GST)] and lipid peroxidation (LPO). The result of this experiment shows that PCB significantly decreases the level of alpha-tocopherol, ascorbic acid and GSH and the activities of SOD, CAT, GPx, GR and GST with elevated levels of ROS and LPO. In addition, decreased epididymal sperm motility and count were observed. Simultaneous supplementation with alpha-tocopherol and ascorbic acid restored these parameters to that of normal range. In conclusion, alpha-tocopherol and ascorbic acid exhibited protective effect on sperm by inhibiting PCB-induced ROS generation.  相似文献   
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Polychlorinated biphenyls (PCBs) are extremely toxic environmental contaminant speculated to accelerate neurochemical and behavioral damages. Developmental and behavioral development relies on the proper functioning of the endogenous neurotransmitters that remain the pivotal target of neurotoxicants. This study intent to evidence the neuroprotective efficacy of quercetin against PCBs induced hippocampal degeneration. Animals were sorted into four (n = 6), Group I: received corn oil (vehicle) intraperitoneally (i.p.); Group II: received quercetin 50 mg/kg bwt (gavage); Group III: were induced with Aroclor 1254 (commercial mixture of PCB) at 2 mg/kg bwt (i.p); Group IV: received quercetin 50 mg/kg bwt (gavage) and along with PCBs 2 mg/kg bwt (i.p.) for 30 days. Cognitive behaviors such as learning and memory were assessed by 8-arm radial maze behavior test throughout the experimental period. Subsequently, anxiety and stress were studied by open field test at the termination of experiment. Hippocampal tissue and blood were collected after the intended experimental period to analyze the levels of oxidative stressors, antioxidants in tissue and estimation of neurotransmitters. Perhaps, PCBs evoke detrimental deterioration of the neurotransmitters and integrative antioxidant defense by elevation of reactive oxygen species (ROS). Concurrent treatment with quercetin prominently suppresses the oxidative stressors, improved the levels of enzymatic antioxidants and neurotransmitter levels significantly at the level of p < 0.05. Behavioral analysis claims drastic revitalization of cognitive functions like learning and memory on treatment with quercetin. The results coalesced depicts neurotoxicity stimulated by PCBs is augmented by simultaneous quercetin administration.  相似文献   
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The stimulatory and inhibitory effects on testicular steroidogenesis of transient neonatal hypothyroidism from day 1 postpartum through different postnatal developmental events on testis at puberal age (60 days old) were studied in vivo. Hypothyroidism was induced in neonates by feeding the lactating mother or directly with 0.05% methimazole (MMI) through drinking water from the day of parturition to 10, 15, 30, 40 and 60 days, and were killed at day 60 postpartum. Plasma and testicular interstitial fluid (TIF) progesterone, testosterone, dihydrotestosterone (DHT) and estradiol concentrations were assessed. Testis weight and volume significantly increased in rats subjected to 10 and 15 days of hypothyroidism, decreased in rats subjected to 30, 40 and 60 days of hypothyroidism. A consistent increase in Leydig cell number was seen in puberal rats subjected to transient neonatal hypothyroidism but decreased in 60 days hypothyroid rats. Peritubular myoid cell number was consistently decreased in all experimental rats. Leydig cell diameter decreased consistently in all experimental groups. Persistent hypothyroidism (60 days hypothyroid) consistently decreased both plasma and TIF sex steroids. In transient hypothyroid rats, progesterone concentration decreased in both plasma and TIF. Transient hypothyroidism from birth to day 10 postnatal age maintained normal titre of plasma testosterone, whereas a significant increase in TIF testosterone concentration was evident when compared with controls. All other groups of rats subjected to transient neonatal hypothyroidism had consistently low titres of plasma and TIF testosterone. Plasma DHT concentrations in rats subjected to transient neonatal hypothyroidism remained unaltered. However, TIF DHT increased in 10 days  相似文献   
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Increased excretion of ethylated DNA bases has been reported in the urine of cigarette smokers. To study DNA ethylation in the target organs of smokers, an immunoenriched (32)P-postlabeling assay for O(4)-ethylthymidine (O(4)-etT) was developed. O(4)-etT-3'-monophosphate (O(4)-etT-3'P) was synthesized, purified, and characterized by LC-MS, ESI-MS, and NMR. DNA was enzymatically digested to 2'-deoxynucleoside-3'-monophosphate followed by immunoprecipitation of O(4)-etT-3'P using specific monoclonal antibodies. The immunoconjugate was washed by filtration, and O(4)-etT-3'P was recovered by ethanol treatment. The enriched O(4)-etT-3'P was labeled with [gamma-(32)P]ATP in the presence of T4-polynucleotide kinase at pH 6.8 to yield its 5'-labeled monophosphate and was subsequently resolved on RP-HPLC and detected with online detection of radioactivity. Adduct recovery was >80%, and the detection limit was approximately 500 amol. To further validate the method, O(4)-etT levels were determined in calf thymus DNA treated with N-ethyl-N-nitrosourea, and a dose-dependent formation of O(4)-etT was observed. Furthermore, O(4)-etT was found to be present in the cells obtained from the lower respiratory tract by sputum induction of two out of four smokers but not in three nonsmokers. O(4)-etT is a poorly repaired promutagenic DNA lesion; thus, it could be of potential use for biomonitoring smoking-related DNA damage. Our improved assay was found to be sufficiently sensitive and specific to detect O(4)-etT in surrogate cells from cigarette smoke exposed humans.  相似文献   
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Petrous apicitis is a rare intracranial complication of otitis media. A 4-year-old female child was presented with persistent ear discharge, retro-orbital pain and lateral rectus palsy (triad of Gradenigo's syndrome). A right temporal burr-hole was placed and tapping was done under antibiotic coverage. Turbid cerebrospinal fluid could be drained. Follow-up could not be done as the patient refused treatment and was discharged against medical advice.  相似文献   
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