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81.
    
The chemical composition of 93 oil samples from the aerial parts of Pituranthos scoparius, harvested in three regions of Algeria, was investigated by GC‐FID, GC/MS and 13C‐NMR. Monoterpene hydrocarbons dominated in association with phenylpropanoids and a chemical variability was found highlighting three clusters. The composition of group I (36 samples) exhibited an atypical composition characterized by a very high contents of 6‐methoxyelemicine (13.0 – 59.6%), followed by sabinene (1.1 – 43.0%) and limonene (6.6 – 39.0%), while the samples of group II (12 samples) contained a high content of limonene (9.2 – 44.0%), followed by myristicine (0.0 – 29.4%) and a lower amount of sabinene (0.8 – 2.3%). Group III (45 samples) could be divided in two subgroups. Subgroup SGIIIA was characterized by a very high content of sabinene (28.0 – 55.6%), followed by elemicine (0.0 – 29.1%), while the samples belonging to SGIIIB were characterized by the lower content of sabinene (6.2 – 35.5%) and a significant content of myristicine (1.5 – 32.4%), α‐pinene (4.2 – 31.0%) and dill apiole (0.1 – 31.4%). Each harvested region was characterized by a different chemical composition.  相似文献   
82.
DNA-based immunizations have been used to determine the patterns of type 1 and type 2 cytokines that can be induced in vivo for Ag-specific CD4(+) and CD8(+) T cells. IL-4 was used as a signature cytokine for a type 2 T cell response and IFN-gamma as the signature cytokine for a type 1 response. Gene gun deliveries of secreted Ags were used to bias responses toward type 2 and saline injections of cell-associated Ags to bias responses toward type 1. The studies revealed that gene gun bombardments of DNAs expressing secreted Ags strongly biased responses toward type 2, inducing IL-4-producing CD8(+) as well as CD4(+) T cells. Saline injections of DNAs expressing cell-associated Ags strongly biased responses toward type 1, inducing IFN-gamma-producing CD8(+) and CD4(+) cells. A mixed type 1/type 2 response of IFN-gamma-producing CD8(+) T cells and IL-4-producing CD4(+) T cells was found for gene gun deliveries of cell-associated Ags. Saline injections of secreted Ags raised a weakly type 1-biased response characterized by only slightly higher frequencies of IFN-gamma- than IL-4-producing CD4(+) and CD8(+) T cells. Studies in B cell knockout and hen egg lysozyme Ig transgenic mice revealed that B cells were required for the generation of IL-4-producing CD8(+) T cells.  相似文献   
83.
Strategies to identify subjects at risk for type 1 diabetes are largely based on the detection of autoantibodies directed to various beta cell autoantigens. Most previous studies only comprise siblings and children of patients with type 1 diabetes; only scare data are available on the antibody profile in older relatives. In this study, we examined the prevalence of cytoplasmic islet cell antibodies (ICA), antibodies to glutamic acid decarboxylase (GADA), antibodies to the protein tyrosine phosphatase IA-2 (IA-2A) and IA-2beta (IA-2betaA) in 531 unaffected parents of patients with type 1 diabetes, and compared the results with antibody frequencies in 2425 siblings. The frequency of ICA, GADA and IA-2A was substantially higher among siblings as compared to parents of patients with type 1 diabetes (8.0% vs. 4.5%, 8.0% vs. 4.3%, and 4.5% vs. 1.9%, respectively; p<0.01). However, subdividing the probands according to age revealed a high prevalence of ICA (5.5 %), GADA (5.9 %), and IA-2A (3.1%) among parents aged 31 -40 years which was similar to that observed in siblings above 20 years of age (6.4%, 6.4%, and 3.1%). In both cohorts, GADA and IA-2A were significantly associated with the presence of ICA. The combined screening for GADA and IA-2A identified 100% of parents and 91.9% of siblings at high risk for type 1 diabetes (>10 JDF-U). Furthermore, the analysis of antibody combinations revealed that among antibody positive individuals the percentage of subjects with two or three antibodies was even higher in parents (69.0%) than in siblings (58.2%). The present study shows a high frequency of single and multiple autoantibodies in unaffected parents of patients with type 1 diabetes. Our data indicate that GAD and IA-2 not only represent the major target of autoantibodies in young siblings but also in adult relatives. These findings may be important for the design of future intervention studies.  相似文献   
84.
Molecular Biology Reports - S-layer proteins in Lactic acid bacteria are not the only cell surface structures used for aggregation, but also plays significant role for intestinal tissue adhesion...  相似文献   
85.
Frontotemporal lobar degeneration (FTLD) is an umbrella term for a heterogeneous group of young-onset dementias of uncertain prevalence and incidence worldwide. Atypical cases of FTLD with fused in sarcoma inclusions (aFTLD-U) have been described recently, but their molecular characterization is still due. Using shotgun mass spectrometry, we identified a total of 107 differentially expressed proteins in the prefrontal cortex, cerebellum and occipital lobe from aFTLD-U patients compared to controls. These proteins are involved in a range of biological pathways such as cellular transport in the prefrontal cortex, energy metabolism in the cerebellum, and protein metabolism in the occipital lobe. In addition, they were validated by selective reaction monitoring (SRM). Comparison of the aFTLD-U proteomic findings with similar studies of Alzheimer's disease and schizophrenia led to identification of proteins that may be related to dementias and psychoses, respectively. Further studies of aFTLD-U and other FTLD subtypes are warranted, although this will require intensive biobanking efforts.  相似文献   
86.
This report presents the first records of meat-eating and ant dipping by wild chimpanzees,Pan troglodytes, from Sierra Leone. The study was conducted in the proposed Outamba-Kilimi National Park, Northern Sierra Leone. Measurements of tools used to dip for driver ants, are compared with those from four other study sites in Africa. The results reveal some fundamentally common characteristics. From both faecal analysis and direct observation, evidence was found that the chimpanzees eat meat. These recordings indicate a varied choice of prey and add new species to those preyed upon by wild chimpanzees. These findings preliminarily support the idea that despite a wide geographical distribution throughout Africa, chimpanzees share some essential conventional behavioural patterns.  相似文献   
87.
Comprehensive genetic testing has the potential to become the standard of care for individuals with hearing loss. In this study, we investigated the genetic etiology of autosomal recessive nonsyndromic hearing loss (ARNSHL) in a Turkish cohort including individuals with cochlear implant, who had a pedigree suggestive of an autosomal recessive inheritance. A workflow including prescreening of GJB2 and a targeted next generation sequencing panel (Illumına TruSightTM Exome) covering 2761 genes that we briefly called as mendelian exome sequencing was used. This panel includes 102 deafness genes and a number of genes causing Mendelian disorders. Using this approach, we identified causative variants in 21 of 29 families. Three different GJB2 variants were present in seven families. Remaining 14 families had 15 different variants in other known NSHL genes (MYO7A, MYO15A, MARVELD2, TMIE, DFNB31, LOXHD1, GPSM2, TMC1, USH1G, CDH23). Of these variants, eight are novel. Mutation detection rate of our workflow is 72.4%, confirming the usefulness of targeted sequencing approach in NSHL.  相似文献   
88.
Species composition and seasonal succession of phytoplankton were analyzed in a lowland river located in South Banat (Ponjavica, Serbia). As a result of human activity, a network of irrigation channels was built on the Ponjavica River’s upper and lower courses. These channels reduce the water level in the river and help to create favorable conditions for accelerated eutrophication processes. Eight phytoplankton divisions with 444 taxa were present. Physical and chemical testing of water, phytoplankton abundance and biomass, as well as chlorophyll a concentration showed a high level of eutrophication. Cyanobacterial biomass developed in 2002 with dominance of Microcystis aeruginosa and Aphanizomenon flos-aquae. Changes in phytoplankton composition were observed during 2008, characterized by the appearance and dominance of Cylindrospermopsis raciborskii when this species accounted for more than 85% of the total phytoplankton biovolume. The change in dominant phytoplankton functional groups was observed: codons H1 and M characterizing summer in 2002 were replaced by codons SN and S1 in 2008. This study compares the presence of C. raciborskii with other phytoplankton species in relation to water quality parameters. High abundance of this species correlated positively with biochemical oxygen demand and turbidity, and negatively with NO3-N concentrations during the study period.  相似文献   
89.
Individual differences in sleep and diurnal preference associate with physical and mental health characteristics, but few genetic determinants of these differences have been identified. A variable number tandem repeat (VNTR) polymorphism in the PERIOD3 (PER3) gene (rs57875989) has been reported to associate with diurnal preference, i.e., preferred timing of waking and sleep. Here, the authors investigate in a prospective single-candidate genetic variant study whether allelic variation for this polymorphism associates also with reported actual sleep timing and sleep duration, as well as psychological and health measures. Six hundred and seventy-five subjects, aged 20 to 35 yrs, completed questionnaires to assess sleep and psychological and health characteristics and were genotyped for the PER3 VNTR. Homozygosity for the longer allele (PER3(5/5)) of the VNTR was associated with increased morning preference, earlier wake time and bedtime, and reduced daytime sleepiness. Separate analyses of work and rest days demonstrated that the increase in time in bed during rest days was greatest in PER3(5/5) homozygotes. PER3 genotype modified the effects of sleep timing and duration on fluid intelligence and body mass index. Genotype was not associated with physical or psychological characteristics as assessed by the SF-36 Health Questionnaire, the General Health Questionnaire, the Big Five Inventory, the Behavioral Inhibition System-Behavioral Activation System scales, and the Positive and Negative Affect Scale, even though these measures varied significantly with diurnal preference as assessed by the Morningness-Eveningness Questionnaire. Whereas diurnal preference also predicts mental health and psychological characteristics, as well as sleep timing, the PER3 VNTR specifically affects measures of sleep timing and may also modify the effects of sleep on health outcome measures.  相似文献   
90.
Nitric oxide (NO) plays a key role in vascular homeostasis. Accurate measurement of NO production by endothelial nitric oxide synthase (eNOS) is critical for the investigation of vascular disease mechanisms using genetically modified animal models. Previous assays of NO production measuring the conversion of arginine to citrulline have required homogenisation of tissue and reconstitution with cofactors including NADPH and tetrahydrobiopterin. However, the activity and regulation of NOS in vivo is critically dependant on tissue levels of these cofactors. Therefore, understanding eNOS regulation requires assays of NO production in intact vascular tissue that do not depend on the addition of exogenous cofactors and have sufficient sensitivity and specificity. We describe a novel technique, using radiochemical detection of arginine to citrulline conversion, to measure NO production within intact mouse aortas, without exogenous cofactors. We demonstrate the presence of arginase activity in mouse aortas which has the potential to confound this assay. Furthermore, we describe the use of N-hydroxy-nor-L-arginine (nor-NOHA) to inhibit arginase and permit specific detection of NO production in intact mouse tissue. Using this technique we demonstrate a 2.4-fold increase in NO production in aortas of transgenic mice overexpressing eNOS in the endothelium, and show that this technique has high specificity and high sensitivity for detection of in situ NO synthesis by eNOS in mouse vascular tissue. These results have important implications for the investigation of NOS regulation in cells and tissues.  相似文献   
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