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31.
MicroRNAs (miRNAs) are small RNA molecules (~ 20–30 nucleotides) that generally act in gene silencing and translational repression through the RNA interference pathway. They generally originate from intergenic genomic regions, but some are found in genomic regions that have been characterized such as introns, exons, and transposable elements (TE). To identify the miRNAs that are derived from palindromic MERs, we analyzed MER paralogs in human genome. The structures of the palindromic MERs were similar to the hairpin structure of miRNA in humans. Three miRNAs derived from MER96 located on chromosome 3, and MER91C paralogs located on chromosome 8 and chromosome 17 were identified in HeLa, HCT116, and HEK293 cell lines. The interactions between these MER-derived miRNAs and AGO1, AGO2, and AGO3 proteins were validated by immunoprecipitation assays. The data suggest that miRNAs derived from transposable elements could widely affect various target genes in the human genome.  相似文献   
32.
Unhealthy dietary habits are key determinants of obesity in adolescents. Assuming that dietary fat profile influences membrane lipid composition, the aim of this study was to analyze structural changes in the erythrocyte membrane of obese compared to normal-weight adolescents. The study was conducted in a group of 11 obese and 11 normal-weight adolescent subjects. The lipid profile, lipid peroxidation and acetylcholinesterase enzyme (AChE) activity were analyzed by conventional methods. The structural properties of reconstituted erythrocyte membrane were characterized by X-ray diffraction. Erythrocyte membrane from obese adolescents had a lipid profile characterized by a higher cholesterol/phospholipid ratio, an increase in saturated fatty acid and a decrease in monounsaturated and n-6 polyunsaturated fatty acid concentrations. Differences in lipid content were associated with changes in the structural properties of reconstituted membranes and the oxidative damage of erythrocyte membrane. The lower oxidative level shown in the obese group (0.15 ± 0.04 vs. 0.20 ± 0.06 nmol/mg for conjugated diene concentrations and 2.43 ± 0.25 vs. 2.83 ± 0.31 nmol/mg protein for malondialdehyde levels) was related to a lower unsaturation index. These changes in membrane structural properties were accompanied by a lower AChE activity (1.64 ± 0.13 vs. 1.91 ± 0.24 nmol AChE/[min mg protein]) in the obese group. The consequences of unhealthy dietary habits in adolescents are reflected in the membrane structural properties and may influence membrane-associated protein activities and functions.  相似文献   
33.
The genetic stability of transgenes is a critical characteristic used to assess constructed cell lines used for vaccine production. The evaluation of gene copy numbers by a qPCR method, is one of the most common approaches used to assess the consistency of transgenes in a constructed cell line. The cell line AV529-19 is a Vero-based cell line specifically engineered to express the HSV-1 UL5 and UL29 open reading frames. AV529-19 is used to support the replication of a defective HSV-2 viral candidate vaccine called HSV529. To assess the genetic stability of the UL5 and UL29 transgenes in AV529-19 cells, a digital PCR-based approach was developed. During characterization of the test method, the specificity, accuracy, and intermediate precision of the assay was investigated based on regulatory guidelines. The developed assay was used to monitor the stability of the transgenes in the manufactured AV529-19 cell lines by comparison of transgene copy numbers in the master cell bank (MCB) with their copy numbers in the extended cell bank (ECB). Results showed that the UL29 and UL5 transgenes are stable in that there are one and three copies of the UL29 and UL5 genes, respectively, per cell in both the AV529-19 MCB and ECB.  相似文献   
34.

Introduction

Advanced care planning (ACP) helps in make decisions on the health problems of people who have lost the capacity for informed consent. It has proven particularly useful in addressing the end of life. The aim of this study was to determine the prevalence of ACP in patients with severe chronic diseases.

Material and methods

Review of medical records of patients with dementia, amyotrophic lateral sclerosis, Parkinson's disease, chronic obstructive pulmonary disease or interstitial lung disease, heart failure, chronic kidney disease on dialysis and cancer, all in advanced stages. We collected data on living wills or registered prior decisions by the physician according to clinical planned.

Results

A total of 135 patients were studied. There was a record of ACP in 22 patients (16.3%). In most of them it was planned not to start any vital treatment in the event of high risk of imminent death and lacking the ability to make decisions. Only two patients were had a legal living will.

Conclusion

The registration of ACP is relatively low, and this can affect decision-making in accordance with the personal values of patients when they do not have the capacity to exercise informed consent.  相似文献   
35.
Kenny-Caffey syndrome (KCS) and the similar but more severe osteocraniostenosis (OCS) are genetic conditions characterized by impaired skeletal development with small and dense bones, short stature, and primary hypoparathyroidism with hypocalcemia. We studied five individuals with KCS and five with OCS and found that all of them had heterozygous mutations in FAM111A. One mutation was identified in four unrelated individuals with KCS, and another one was identified in two unrelated individuals with OCS; all occurred de novo. Thus, OCS and KCS are allelic disorders of different severity. FAM111A codes for a 611 amino acid protein with homology to trypsin-like peptidases. Although FAM111A has been found to bind to the large T-antigen of SV40 and restrict viral replication, its native function is unknown. Molecular modeling of FAM111A shows that residues affected by KCS and OCS mutations do not map close to the active site but are clustered on a segment of the protein and are at, or close to, its outer surface, suggesting that the pathogenesis involves the interaction with as yet unidentified partner proteins rather than impaired catalysis. FAM111A appears to be crucial to a pathway that governs parathyroid hormone production, calcium homeostasis, and skeletal development and growth.  相似文献   
36.
A new porcine parvovirus (PPV), provisionally designated as PPV5, was identified in U.S. pigs. Cloning and sequencing from a circular or head-to-tail concatemeric array revealed that the PPV5 possesses the typical genomic organization of parvoviruses with two major predicted open reading frames (ORF1 and ORF2), and is most closely related to PPV4 with overall genomic identities of 64.1–67.3%. The amino acid identities between PPV5 and PPV4 were 84.6%–85.1% for ORF1 and 54.0%–54.3% for ORF2. Unlike PPV4, but similar to bovine parvovirus 2 (BPV2), PPV5 lacks the additional ORF3 and has a much longer ORF2. Moreover, the amino acid sequences of ORF1 and ORF2 of BPV2 showed higher homologies to PPV5 than to PPV4. The conserved motifs of the Ca2+ binding loop (YXGXG) and the catalytic center (HDXXY) of phospholipase A2 (PLA2) were identified in VP1 (ORF2) of PPV5, as well as in BPV2, but were not present in PPV4. Phylogenetic analyses revealed that PPV5, PPV4 and BPV2 form a separate clade different from the genera Parvovirus and Bocavirus. Further epidemiologic investigations of PPV4 and PPV5 in U.S. pigs of different ages indicated a slightly higher prevalence for PPV5 (6.6%; 32/483) compared to PPV4 (4.1%; 20/483), with detection of concurrent PPV4 and PPV5 in 15.6% (7/45) of lungs of infected pigs. Evidence for potential vertical transmission or association with reproductive failure was minimal for both PPV4 and PPV5. The high similarity to PPV4 and the lack of ORF3 may suggest PPV5 is an intermediate of PPV4 during the evolution of parvoviruses in pigs.  相似文献   
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39.

Background

The “Timed Up and Go” (TUG) is a widely used measure of physical functioning in older people and in neurological populations, including Parkinson’s Disease. When using an inertial sensor measurement system (instrumented TUG [iTUG]), the individual components of the iTUG and the trunk kinematics can be measured separately, which may provide relevant additional information.

Objective

The aim of this study was to determine intra-rater, inter-rater and test-retest reliability of the iTUG in patients with Parkinson’s Disease.

Methods

Twenty eight PD patients, aged 50 years or older, were included. For the iTUG the DynaPort Hybrid (McRoberts, The Hague, The Netherlands) was worn at the lower back. The device measured acceleration and angular velocity in three directions at a rate of 100 samples/s. Patients performed the iTUG five times on two consecutive days. Repeated measurements by the same rater on the same day were used to calculate intra-rater reliability. Repeated measurements by different raters on the same day were used to calculate intra-rater and inter-rater reliability. Repeated measurements by the same rater on different days were used to calculate test-retest reliability.

Results

Nineteen ICC values (15%) were ≥ 0.9 which is considered as excellent reliability. Sixty four ICC values (49%) were ≥ 0.70 and < 0.90 which is considered as good reliability. Thirty one ICC values (24%) were ≥ 0.50 and < 0.70, indicating moderate reliability. Sixteen ICC values (12%) were ≥ 0.30 and < 0.50 indicating poor reliability. Two ICT values (2%) were < 0.30 indicating very poor reliability.

Conclusions

In conclusion, in patients with Parkinson’s disease the intra-rater, inter-rater, and test-retest reliability of the individual components of the instrumented TUG (iTUG) was excellent to good for total duration and for turning durations, and good to low for the sub durations and for the kinematics of the SiSt and StSi. The results of this fully automated analysis of instrumented TUG movements demonstrate that several reliable TUG parameters can be identified that provide a basis for a more precise, quantitative use of the TUG test, in clinical practice.  相似文献   
40.
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