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101.
Context: Topical treatment of skin disease needs to be strategic to ensure high drug concentration in the skin with minimum systemic absorption.

Objective: The aim of this study was to produce semisolid nanostructured lipid carrier (NLC) formulations, for topical delivery of the corticosteroid drug, diflucortolone valerate (DFV), with minimum systemic absorption.

Method: NLC formulations were developed using a high shear homogenization combined with sonication, using Precirol® ATO5 or Tristearin® as the solid lipid, Capryol? or isopropyl myristate as the liquid lipid and Poloxamer® 407 as surfactant. The present study addresses the influence of different formulations composition as solid lipid, liquid lipid types and concentrations on the physicochemical properties and drug release profile from NLCs.

Results and discussion: DFV-loaded NLC formulations possessed average particle size ranging from 160.40?nm to 743.7?nm with narrow polydispersity index. The encapsulation efficiency was improved by adding the lipid-based surfactants (Labrasol® and Labrafil® M1944CS) to reach 68%. The drug release from the investigated NLC formulations showed a prolonged release up to 12?h. The dermatopharmacokinetic study revealed an improvement in drug deposition in the skin with the optimized DFV-loaded NLC formulation, in contrast to a commercial formulation.

Conclusion: NLC provides a promising nanocarrier system that work as reservoir for targeting topical delivery of DFV.  相似文献   

102.
There is increasing evidence that oxidative stress may play a role in the pathophysiology of hyperemesis gravidarum. Serum paraoxonase-1 (PON-1) is a high density lipoprotein (HDL)-associated enzyme that prevents oxidative modification of low density lipoprotein. The aim of the study was to measure the serum levels of PON-1 activity in women with hyperemesis gravidarum. Thirty-four women with hyperemesis gravidarum and 31 healthy pregnant women were enrolled in the study. Serum PON-1 activity was measured spectrophotometrically. Lipid hydroperoxide (LOOH) levels were measured by iodometric assay. PON-1 activity was significantly lower and LOOH levels were significantly higher in pregnant women with hyperemesis gravidarum than in healthy pregnant women (P < 0.0001, for all). There were significant correlations between PON-1 and LOOH, triglyceride, total cholesterol, HDL, low density lipoprotein (LDL) and high sensitive C-reactive protein (HSCRP; P < 0.0001, for all). By using multiple regression analysis LDL, HDL, HSCRP and LOOH were independent determinants of serum PON-1 activity in the study. Decreased PON-1 activity might be related to increased oxidative stress and inflammation in pregnant women with hyperemesis gravidarum. Subjects with hyperemesis gravidarum might be more prone to the development of atherogenesis due to low serum PON-1 activity.  相似文献   
103.
Unal F  Duran A  Martin E 《Hereditas》2008,145(2):64-68
This study examined chromosome numbers and karyotypes of four taxa, Hesperis novakii Dvorák, H. bottae Fourn., H. balansae Fourn. and H. syriaca (DC.) Dvorák, from naturally growing Diaplictos (Dvorák) Dvorák section, which is represented by only these four taxa in Turkey, in the genus Hesperis. H. novakii and H. syriaca have 2n=14 chromosomes, H. bottae and H. balansae have 2n=12 chromosomes in somatic cells. Total chromosome lengths are 5.37 mum and 2.17 mum in H. novakii, 5.38 mum and 2.70 mum in H. bottae, 9.59 mum and 4.28 mum in H. balansae, 4.88 mum and 2.32 mum in H. syriaca (no. 4969), 7.89 mum and 3.44 mum in H. syriaca (no. 4971). The karyotypes are as follows: H. novakii consists of 3m+1sm+1st+2T, H. bottae consists of 4m+2st, H. balansae consists of 4m+2sm, H. syriaca (no. 4969) consists of 3m+1sm+1st+2T and H. syriaca (no. 4971) consists of 3m+1sm+1st+2T chromosome pairs. Results were discussed from a cytological and taxonomical point of view.  相似文献   
104.
N,N′-Bis[allylamino]glyoxime, N,N′-bis[anilino]glyoxime, and N,N′-bis[1,2,3,4-tetrahydro-5-naphthalenamino]glyoxime have been prepared from corresponding amines and (E,E)-dichloroglyoxime. These ligands gave orange-red compound with NiCl2 in less acidic medium (pH ∼ 5) that are bis(E,E-dioximato)nickel(II) complexes {[(E,E)-Ni(HL)2]} (1a-3a) and green compounds in acidic medium (pH ∼ 2) that are tris(E,E-dioximato)nickel(II) dichloride complexes {[(E,E)-Ni(LH2)3]Cl2} (1b-3b). The crystal structures of all complexes have been determined by X-ray diffraction on a single crystal. The study of absorption spectra of these two types of complexes shows that they may be converted to each other by addition of acids (1a-3a) or bases (1b-3b) and there is no way for the amphi form.  相似文献   
105.
Chemical investigation of endemic Algerian plant Launaea arborescens resulted in the isolation of a series of triterpenes and sesquiterpenes from both the aerial parts and roots. Five terpenoids have been chemically characterised by means of spectral methods mainly NMR techniques. In addition, the absolute stereochemistry at the chiral carbon in the side chain of 8-deoxy-15-(3′-hydroxy-2′-methyl-propanoyl)-lactucin-3′-sulfate (6) has been determined by comparison of the 1H NMR spectra of Mosher derivatives of 6 with those of the corresponding MTPA esters of model compounds.  相似文献   
106.
Obesity is a complex disease caused by both genetics and environmental factors. Melanocortin-4 receptor (MC4R) (MIM 155541) gene polymorphisms were reported to be the cause of monogenic obesity in humans. We studied three polymorphisms (Val50Met, Val103Ile, and Ser58Cys) and a mutation (Asn274Ser) of the MC4R gene in 203 obese patients and in 110 healthy subjects in the Turkish population. A high incidence of Val103Ile and Val50Met polymorphisms as well as the Asn274Ser mutation was found in the obese patients, whereas no significant correlation was found regarding the Ser58Cys polymorphism. We conclude that there is a concordance between the polymorphisms (Val103Ile, Val50Met, Ser58Cys) that were first studied in the Turkish population with obesity.  相似文献   
107.
AimsIn this study, the effects of four single nucleotide polymorphisms (SNPs), ? 3860G > A, ? 2467delT, ? 739T > G and ? 163C > A, of CYP1A2 gene on lung cancer were evaluated in Tunisian population.Main methodsFour polymorphisms of CYP1A2 gene were analysed in 109 healthy smokers and in 101 lung cancer cases, including 63 with squamous cell carcinoma (SCC) and 41 with adenocarcinoma (AD). The genotyping for the SNPs ? 3860 G > A, ? 2467delT, ? 739T > G and ? 163C > A was performed by polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis.Key findingsThe results showed that smokers with CYP1A2 gene polymorphisms were associated with an increased risk for the development of lung AD. There was however no significant increased risk of developing lung SCC in smokers having CYP1A2 gene polymorphisms. An increased risk of developing AD was observed in smokers who are carriers of at least one copy of ? 3680A or ? 739G giving a significant odds ratio (OR) of 6.02 (CI = 2.91–12.9) and 3.01 (CI = 1.54–5.98), respectively.SignificanceThese genotyping data are consistent with the hypothesis that tobacco-specific-N-nitrosamines (TSN) such as 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) are major contributors to the development of lung AD and that CYP1A2 gene product plays an important role in the metabolic activation of NNK. This study suggests that SNPs of CYP1A2 could be considered as promising biomarkers in the aetiology of lung AD in smokers.  相似文献   
108.
109.
Background: The p53 polymorphisms have been extensively studied as putative breast cancer susceptibility variants. The present study was undertaken to investigate the association of p53 Arg72Pro, Ins16bp and G13964C polymorphisms and their haplotypes with breast cancer risk in Tunisian women. Methods: Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) on 159 patients and 132 controls. Results: The G13964C intronic variant was significantly associated with familial breast cancer risk (p = 0.0018) while the genotypic distribution was similar for p53 Arg72Pro and Ins16bp in patients and controls. Moreover, the (NoIns-C), (Arg-C) and (NoIns-Arg-C) haplotypes were significantly associated with familial breast cancer risk (p = 0.0021, p = 0.0096 and p = 0.0084, respectively) while there was a trend of association between the (Ins-Arg) and (Ins-Arg-G) haplotypes and the risk of sporadic breast cancer. Only the G/C genotype as well as the (NoIns-C) haplotype remained significant after correction for multiple testing. Conclusion: Our data revealed an association between the G/C genotype and the (NoIns-C) haplotype and the risk of familial breast cancer in Tunisian women. However, these observations need to be confirmed due to the limited statistical power of our study and the small number of cases.  相似文献   
110.
Compounds containing nitrogen and sulfur atoms can be widely used in various fields, including industry, medicine, biotechnology, and chemical technology. Among them, amides of acids and heterocyclic compounds have an important place. These amides and thiazolidine‐4‐ones showed good inhibitory action against butyrylcholinesterase (BChE), acetylcholinesterase (AChE), and human carbonic anhydrase isoforms. AChE exists at high concentrations in the brain and red blood cells. BChE is an important enzyme that is plentiful in the liver, and it is released into the blood in a soluble form. They were demonstrated to have effective inhibition profiles with Ki values of 23.76–102.75 nM against hCA I, 58.92–136.64 nM against hCA II, 1.40–12.86 nM against AChE, and 9.82–52.77 nM against BChE. On the other hand, acetazolamide showed Ki value of 482.63 ± 56.20 nM against hCA I, and 1019.60 ± 163.70 nM against hCA II. Additionally, Tacrine inhibited AChE and BChE, showing Ki values of 397.03 ± 31.66 and 210.21 ± 15.98 nM, respectively.  相似文献   
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