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1.
IQGAPs genes play critical role in either induction or suppression of cancer and its progression, however the relationship between Ras genes and these genes are still unclear. In this study, we tried to understand the mechanistic action of IQGAPs genes and its correlation with Ras genes in mouse hepatic cancer model. The genetic expressions of IQGAP1, IQGAP2, IQGAP3, Hras, Kras, Nras, Mras, Caspase3, and BAX were followed in both hepatocellular carcinoma and normal liver cells of Balbc mice. Genotoxic agent diethylnitrosamine (DEN)-induced hepatic cancer model was induced in male mice and recorded the occurrence of hepatocellular carcinoma by morphological and histological changes in the liver. It was observed that mRNA expressions of IQGAP1, Hras, Kras, Nras, Mras, Caspase3, and BAX genes were highly elevated in hepatocellular carcinoma cells when compared with normal liver cells, additionally their expressions increased by concentrating the dose of DEN. While, the expressions of IQGAP2 and IQGAP3 were significantly decreased in hepatocellular carcinoma cells when compared with normal liver cells, as well as their expressions decreased more with increasing the dose of DEN. It was concluded from this study that IQGAP1 has a strong signaling relationship with Ras genes in induction of cancer and it is considered as a key gene for induction or suppression of the hepatocellular carcinoma.  相似文献   
2.
OBJECTIVE: To describe the extent and characteristics of injection use and injection providers in Egypt, given that unsafe injections are associated with blood-borne pathogen transmission. METHODS: Household surveys of a population-based sample of residents in the Nile Delta and in Upper Egypt; focus group discussions and in-depth interviews with community target groups, formal and informal medical providers. RESULTS: Of 4197 persons interviewed, 26.2% reported receiving an injection in the past 3 months. Of these, 77% reported it was for therapeutic indications. The age-sex specific prevalence of injections was highest among children 0-2 years of age and among older adults. Women were more likely to report having an injection than men, particularly at the age above 20 years. Overall, respondents reported receiving on average 4.2 injections per year, indicating that up to 281 million injections are provided per year in Egypt. Injection administrators were public and private sector physicians, pharmacists, barbers, doctor assistants, housekeepers, relatives and friends. Injection prescribers were mostly private and public sector physicians. Of the 1101 respondents who received an injection in the past 3 months, 92 (8.4%) reported that the provider did not use a syringe taken from a closed sealed packet. CONCLUSION: The frequency of therapeutic injection use is high in Egypt and may contribute to blood-borne pathogen transmission. The Ministry of Health and Population (MOHP) is developing interventions targeted towards promotion of injection safety and reduction of injection overuse on community basis as part of a comprehensive strategy to prevent blood-borne pathogen transmission in Egypt.  相似文献   
3.
OBJECTIVE: To study Langerhans's cells (LCs) in cervical squamous cell carcinoma. STUDY DESIGN: The study was carried out in the Shatby University Hospital, Alexandria, Egypt. Thirty cases with squamous cell carcinoma, 10 cases with cervical intra-epithelial neoplasia (CIN) and 10 cases with normal exocervix were recruited. Sections from the exocervix were stained with gold chloride, immunostaining with S-100 protein antiserum, adenosine triphosphatase ATPase and electron microscopy. Statistical evaluation was done using the t-test. RESULTS: Gold chloride staining revealed significantly increased number of LCs in all cases of CIN compared to normal controls and with increasing grade of CIN (p < 0.001). No relationship between LCs number and the grade of carcinoma. Least branched LCs were predominant in the normal tissue while in neoplasia, these cells were of the most branched type, indicating a hyperactivity. S-100 protein positive LCs were almost absent in normal controls while their number were almost lower than the corresponding cases of CIN and invasive carcinoma after gold chloride or ATPase stainings. Signs of hyperactivity were evident in LCs of neoplastic cases after electron microscopy. CONCLUSIONS: Proliferation and increased number of LCs in CIN is an immune response, while such reaction is suppressed by invasive carcinoma.  相似文献   
4.
Direct cytotoxic effects associated with hemoglobin (Hb) or myoglobin (Mb) have been ascribed to redox reactions (involving either one- or two-electron steps) between the heme group and peroxides. These interactions are the basis of the pseudoperoxidase activity of these hemoproteins and can be cytotoxic when reactive species are formed at relatively high concentrations during inflammation and typically lead to cell death. Peroxides relevant to biological systems include hydrogen peroxide, lipid hydroperoxides, and peroxynitrite. Reactions between Hb/Mb and peroxides form the ferryl oxidation state of the protein, analogous to compounds I and II formed in the catalytic cycle of many peroxidase enzymes. This higher oxidation state of the protein is a potent oxidant capable of promoting oxidative damage to most classes of biological molecules. Free iron, released from Hb, also has the potential to promote oxidative damage via classical "Fenton" chemistry. It has become increasingly evident that Hb/Mb redox reactions or their by-products play a critical role in the pathophysiology of some disease states. This review briefly discusses the reactions of Hb/Mb with biological peroxides, potential cytotoxicity and the impact of these interactions on modulation of cell signaling pathways regulated by these reactive species. Also discussed in this article is the role of heme-protein chemistry in relation to the toxicity of hemoproteins.  相似文献   
5.
Chemically modified hemoglobin (Hb) solutions are promising oxygen therapeutics; however, these agents are prone to intravascular oxidation. Using a 50% exchange transfusion (ET) model with bovine polymerized hemoglobin (PolyHbBv), we examined heme oxidation, oxygenation markers, and toxicokinetics in rats, an ascorbic acid (AA)-producing species, and in guinea pigs, a non-AA-producing species. Plasma AA decreased by 50% in guinea pigs after ET, but it was unchanged in rats for the first 20 h post-ET. Both species cleared PolyHbBv from the circulation at similar rates. However, exposure to ferric PolyHbBv over time was 5-fold greater in the guinea pig. Mass spectrometry analysis of plasma revealed oxidative modifications within the tetrameric fraction of PolyHbBv in guinea pig. Oxygen equilibrium curves of PolyHbBv measured in plasma after ET were more left-shifted in guinea pigs compared with rats, consistent with increased ferric PolyHbBv formation. Renal hypoxia-inducible factor (HIF)-1alpha, whose activity strictly depends on the partial pressure of oxygen increased over time, and it correlated inversely with circulating ferrous PolyHbBv in both species. Interestingly, HIF-1alpha activity was greater in guinea pigs compared with rats at 72 h post-ET. Mean arterial pressure increases were also greater in guinea pigs; however, minimal differences in cardiac and renal pathology were observed in either species. The present findings suggest the importance of plasma AA in maintaining the stability of acellular Hb susceptible to oxidation, and they may be relevant to humans, which display a similar plasma/tissue antioxidant status to guinea pig.  相似文献   
6.
Deep vein thrombosis (DVT) is a common multi-factorial disease, with serious short- and long-term complications, and a potential fatal outcome. Many genes are involved in determining the interindividual variation in traits that define the onset and progression of disease, as well as the response to treatment. Several association studies have designed the relationship between factor XII C46T polymorphism and the risk of arterial and venous thrombosis. Some studies reported that FXII gene polymorphism is not associated with venous thrombosis, whereas other studies found an increased risk of venous thrombosis in carriers of a FXII-T variant. We constructed an age–gender–ethnic–matched case–control study including 52 DVT patients and 100 healthy volunteers. C46T polymorphism of the coagulation factor XII was carried out using allelic discrimination assay by real-time polymerase chain reaction for patients and controls, while plasma factor XII activity was detected by one-step clotting assay. FXII C46T genotyping in DVT patients revealed that 34.6% were heterozygous harboring the FXII-CT heterotype and 3.85% were homozygous; FXII-TT homotype, with no statistically significant difference in the distribution of the mutant genotypes between DVT patients and the control group. FXII activity was significantly reduced in DVT patients harboring the mutant genotypes. In the present study, FXII C46T gene polymorphism was not associated with increased risk of deep venous thrombosis.  相似文献   
7.
ObjectivesThis study aimed at exploring the role of curcumin and taurine alone or in combination against cultured human hepatoma cells (Huh-7 cells).Design and methodsHuh-7 cells were plated and treated with various concentrations of curcumin and/or taurine. Hemocytometer cell count, cell viability, quantification of γ-IFN concentrations, and flow cytometric analyses for CD4, CD8, and CD25 were carried out.ResultsThere were significant increases in the levels of cell density, γ-IFN, and CD8, accompanied with significant decrease in the level of CD4, when comparing cultured cells treated with curcumin and taurine with control cultured cells.ConclusionCurcumin/taurine in combination formula is better treatment than single therapy, with respect to cell density and γ-IFN. Moreover, curcumin/taurine combined therapy enhances immunity by stimulating the CD4+ T-helper cells with consequent induction of CD8 T-cell responses to lyse tumor cells.  相似文献   
8.
Efficient extracellular hemoglobin (Hb) clearance is essential to prevent oxidative- and nitrosative-mediated toxicity. CD163 belongs to group B of the scavenger receptor cysteine-rich (SRCR) protein family found on the surface of monocytes and macrophages and is responsible for Hb-haptoglobin (Hp) complex uptake. Hb uptake by CD163 was thought to proceed exclusively through an Hp-dependent pathway. However, Hb can interact directly with CD163 via a low affinity binding when Hp is absent. As a result, a two-phase hypothesis of Hb clearance by monocytes/macrophages suggests that Hp-Hb binding to CD163 is the primary mechanism of plasma Hb clearance, while clearance of Hb by direct binding to CD163 is secondary to Hp depletion. The authors have considered the ligand specificity of CD163 in human macrophages and in a heterologous gene expression model to demonstrate that Hb is effectively endocytosed by CD163 in the absence of Hp. Additionally, the authors have considered Hb-based oxygen carriers (HBOCs) administration as a unique situation during which direct CD163 uptake may be relevant as a mechanism of clearance. However, the nature of chemical modifications introduced onto the Hb molecule and/or oxidative changes induced in the protein appear to influence the extent of CD163 interaction and cellular uptake. Here, an overview and novel insights into the role of CD163 in Hb redox inactivation and clearance are provided.  相似文献   
9.
An analytical method using natural analcime zeolite modified with tppz (2,3,5,6-tetra-pyridylpyrazine) for preconcentration of cadmium, in a column system, and their sequential determination by flame atomic absorption spectrometry (FAAS), was developed. In this work, cadmium was adsorbed onto natural analcime zeolite modified with tppz and then was recovered by nitric acid. Solutions of cadmium were passed through a glass column packed with 100?mg of the sorbent material, at pH 5.0, and cadmium was eluted with 2.0?M HNO(3) at a flow rate of 2.0?ml?min(-1). The relative standard deviation (RSD) for eight replicate determinations at the 2.5?μg of cadmium was ±0.94%. The calibration curve using the preconcentration system was linear from 0.01 to 4?μg?ml(-1) in final solution with a correlation coefficient of 0.9993. This method was successfully applied for the determination of cadmium in various samples.  相似文献   
10.
Plasma zinc and copper concentrations were determined by atomic absorption spectroscopy in 57 patients with sickle cell anemia and in 45 control subjects from the Eastern Province of Saudi Arabia. Plasma zinc and copper levels in patients were found to be close to those of the control subjects. Similarly, there was a difference neither in urinary zinc level nor in the ratio Cu:Zn in patients and control subjects. This is in contrast to the situation which exists in North American Black subjects with sickle cell anemia, who are known to have zinc deficiency as well as a further decrease in zinc level during sickle cell crises. The near-normal levels of zinc and copper found in Saudi sickle cell patients therefore exclude zinc deficiency and confirm that this population exhibits a milder form of sickle cell anemia.  相似文献   
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