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171.
Hair analysis is a promising tool for routine clinical screening and diagnosis of heavy metal exposure and essential trace element status in the human body. Systemic intoxications have been identified by anomalously high values of toxins in hair samples. The aim of the present study is to evaluate the relationship between smoking habit of the family members and the levels of toxic and nontoxic trace elements in hair samples of children. The randomized cross-sectional controlled study comprised of 95 children (41 girls and 54 boys) between the ages of 1 and 6 years. After written informed consent was obtained, a face-to-face interview was conducted with the families about educational background, total income of the family, and smoking habits of family members. The mineral elements considered in this study were Zn, Se, B, V, Co, Mo, Mn, iron (Fe), Be, aluminum (Al), As, cadmium (Cd), lead (Pb), Hg, chromium (Cr), Ag, Be, nickel (Ni), copper (Cu), Sn, and antimony (Sb). Hair mineral contents were measured by inductively coupled plasma-mass spectrometry. The results showed that the levels of Cd, Pb, Cr, Sb, Fe, and Al in hair samples of children whose parents smoked were significantly higher than those whose parents were nonsmokers. The number of smokers and the frequency of smoking at home were positively correlated with Pb, Cd, Cu, Ni, and Sb levels found. At the same time, it was found that there was no correlation between toxic element concentrations and family income or educational background excluding the levels of Cd. A correlation was observed between the smoking status of family members and levels of toxic trace elements in hair where this correlation was more significant with the levels of Pb and Cd. High socioeconomic status and the level of education of family members did not have any effect on toxic trace levels in hair samples of children.  相似文献   
172.
The aim of this study was to evaluate the prevalence and prognostic role of increased gene copy number and protein expression of MET and EGFR in non-small cell lung cancer (NSCLC) patients. Samples were collected from 380 patients with surgically resected NSCLC, and fluorescence in situ hybridisation (FISH) and immunohistochemistry (IHC) were performed. EGFR amplification and high polysomy (EGFR FISH-positive) were observed in 9.7% and 17.4% of the patients, respectively. EGFR was overexpressed (EGFR IHC-positive) in 19.2% of the patients. Neither EGFR FISH-positive nor EGFR IHC-positive status affected survival after resection. Increased MET copy number (MET FISH-positive by University of Colorado Cancer Center criteria) was observed in 11.1% of the patients (high polysomy, 8.7%; gene amplification, 2.4%). According to the Cappuzzo system, 7.1% of the patients were MET FISH-positive. MET FISH positivity was a negative prognostic factor, especially in patients with adenocarcinoma histology (p=0.040), female gender (p=0.010), old age (p=0.084), and EGFR FISH negativity (p=0.020) at the univariate level but not at the multivariate level. MET was overexpressed (MET IHC-positive) in 13.7% of the patients and associated with shorter overall and disease-free survival (p=0.010 and p=0.056, respectively). Multivariate analysis revealed that MET IHC-positive patients had a significantly increased risk of death (hazard ratio, 1.618; 95% confidence interval, 1.066-2.456; p=0.024). Increased MET copy number and MET overexpression are negative prognostic factors for surgically resected NSCLCs.  相似文献   
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Background

Nicotine dependence (ND) is characterized by regular smoking, anxiety, irritation, difficulty concentrating, impatience, restlessness, tremor, dizziness, hunger, nicotine demand, and the individual’s reluctance to quit despite knowing the health risks of smoking. Recently, it has been reported that the Neuregulin 3 (NRG3)/Erb-B2 receptor tyrosine kinase 4 (ERBB4) signaling pathway plays a role in ND. NRG3, which is activated after nicotine intake, binds to ERBB4 and causes GABA release. GABA reduces anxiety and tension, which are one of the nicotine withdrawal symptoms. Therefore we aimed to investigate the relationship between NRG3 and ERBB4 gene polymorphisms and ND.

Materials and methods

The study population was comprised of patients with ND (n?=?200) and healthy non-smoker control subjects (n?=?200) who were matched for age, sex, and compared for comorbidity factors such as alcohol, smoking, duration, and education (age range 18–60). Genotypes were detected by Real-Time PCR using TaqMan technology. The Fagerström Nicotine Dependence Test (FTND) score was 5 and above for the patient group and 0 for the control group. DNA was obtained from whole peripheral blood and six polymorphisms of Neuregulin 3 (NRG3) (rs1836724, rs7562566, and rs10048757) and Erb-B2 Receptor Tyrosine Kinase 4 (ERBB4) (rs1764072, rs6584400, and rs10883934) genes were analyzed by real-time PCR method.

Results

Our findings show that the six selected SNPs are not significantly associated with ND in the Turkish population and no correlation with dependence levels (p?>?0.05).

Conclusion

Although our findings do not show a relationship between ND and these polymorphisms, it is the first study to investigate these single nucleotide polymorphisms (SNPs) for the first time in ND and to find some genotypes in the Turkish population when compared to other populations. Also, our findings are important in terms of their contribution to the literature and forensic genetics.

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176.
Essential thrombocythemia (ET) is an entity of classic Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs), characterized by thrombocytosis with megakaryocytic hyperplasia and thrombocytes are increased with abnormal functions. Discovery of the protein tyrosine kinase JAK2 V617F allele contributed to better understanding of the pathogenetic mechanisms of MPNs. Acquired single point mutation in the JAK2 V617F was determined approximately 50–60 % of patients with ET. In this study we aimed to investigate the relationship between JAK2 V617F gene mutation, hematologic, biochemical markers and the complications in the ET patients. A total of 268 patients diagnosed with ET and 219 of those studied for JAK2 gene mutation were followed at the hematology clinics of three major hospitals between 2008 and 2013 were screened retrospectively. Laboratory, clinical and hematologic parameters were compared for JAK2 V617F positive and JAK2 V617F negative patients with ET. 102 (46 %) patients were positive with the JAK2 V617F mutation. The complications were observed in 61 (28 %) patients and 38 (62 %) of them had JAK2 V617F mutation. The levels of white blood cells, neutrophil, basophil, red blood cells, hemoglobin, hematocrit, mean platelet volume, thrombocytes, eosinophil; urea, creatinine were significantly different in patients with the JAK2 V617F mutation (P < 0.05). Presence of the JAK2 V617F mutation supports the diagnosis of ET. It would be useful to investigate the JAK2 V617F mutation and the hematologic and biochemical markers at diagnosis with respect to consider the risk of developing complications and to take the precautions against these complications.  相似文献   
177.
Abstract

A series of polymethoxylated-pyrazoline benzene sulfonamides were synthesized, investigated for their cytotoxic activities on tumor and non-tumor cell lines and inhibitory effects on carbonic anhydrase isoenzymes (hCA I and hCA II). Although tumor selectivity (TS) of the compounds were less than the reference compounds 5-Fluorouracil and Melphalan, trimethoxy derivatives 4, 5, and 6 were more selective than dimethoxy derivatives 2 and 3 as judged by the cytotoxicity assay with the cells both types originated from the gingival tissue. The compound 6 (4-[3-(4-methoxyphenyl)-5-(3,4,5-trimethoxyphenyl)-4,5-dihydro-1H-pyrazol-1-yl] benzene sulfonamide) showed the highest TS values and can be considered as a lead molecule of the series for further investigations. All compounds synthesized showed superior CA inhibitory activity than the reference compound acetazolamide on hCA I, and II isoenzymes, with inhibition constants in the range of 26.5–55.5?nM against hCA I and of 18.9–28.8?nM against hCA II, respectively.  相似文献   
178.
Doxorubicin (DOX) is a chemotherapeutic agent, and is widely used in cancer treatment. The most common side effect of DOX was indicated on cardiovascular system by experimental studies. There are some studies suggesting oxidative stress-induced toxic changes on liver related to DOX administration. The aim of the present study was to evaluate whether antioxidant N-acetylcysteine (NAC) relieves oxidative stress in DOX- induced liver injury in rat. Twenty-four male rats were equally divided into three groups. First group was used as a control. Second group received single dose of DOX. NAC for 10 days was given to constituting the third group after giving one dose of DOX. After 10 days of the experiment, liver tissues were taken from all animals. Lipid peroxidation (LP) levels were higher in the DOX group than in control whereas LP levels were lower in the DOX+NAC group than in control. Vitamin C and vitamin E levels were lower in the DOX group than in control whereas vitamin C and vitamin E levels were higher in the DOX+NAC group than in the DOX group. Reduced glutathione levels were higher in the DOX+NAC group than in control and DOX group. Glutathione peroxidase, vitamin A and β-carotene values were not changed in the three groups by DOX and NAC administrations. In histopathological evaluation of DOX group, there were mononuclear cell infiltrations, vacuolar degeneration, hepatocytes with basophilic nucleus and sinusoidal dilatations. The findings were totally recovered by NAC administration. In conclusion, N-acetylcysteine induced modulator effects on the doxorubicin-induced hepatoxicity by inhibiting free radical production and supporting the antioxidant vitamin levels.  相似文献   
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In this study, 4-[3-(4-hydroxyphenyl)-5-aryl-4,5-dihydro-pyrazol-1-yl]benzenesulfonamide (19) types compounds were synthesized and their chemical structures were confirmed by 1H NMR, 13C NMR and HRMS spectra. Cytotoxic and carbonic anhydrase (CA) inhibitory effects of the compounds were investigated. Cytotoxicity experiments pointed out that compound 4, (4-[5-(4-chlorophenyl)-3-(4-hydroxyphenyl)-4,5-dihydro-pyrazol-1-yl]benzenesulfonamide), exerting the highest tumor selectivity (TS) and potency selectivity expression (PSE) values, can be considered as a lead compound of this study in terms of development of novel anticancer agents. All synthesized sulfonamides showed a good inhibition profile on hCA IX and XII in the range of 53.5–923?nM and 6.2–95?nM, respectively. These compounds were 2.5–13.4 times more selective for the inhibition of hCA XII versus hCA IX, except compound 2 which had similar inhibitory action towards both isoenzymes.  相似文献   
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