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71.
The aim of investigation was to assess the impact of subjective stress exposure on delinquent behaviour in children and adolescents. The study included 174 young male delinquents, selected by the method of stratified systematic (random) sample and divided into three age groups of <14, 14-17, and 18-21 years. General data, data on the type of criminal offence, and data on the type of deviant behaviour were collected. A standardised scale of subjective stress was used to allow for comparison of the results obtained in the study with those reported elsewhere. Analysis of variance, chi2-test and factor analysis were used on data processing. A majority of study subjects (55.2%) committed one criminal offence. The criminal offence structure was predominated by proprietary violation (66.7%). Common forms of deviant behaviour included shirking school duties (55.2%), and aggressive behaviour at school (31.0%), in public (29.5%) and in the family (23.6). Parental distrust and punishment (abuse) of the child were identified as the major sources of subjective stress. Youngest subjects significantly differed from other age groups according to their experience of subjective stress described as punishment (abuse) (F = 22.1389, p < 0.001). They were considerably more vulnerable to this type of stress than older age groups. These sources of stress were found to positively correlate with the number of criminal offences committed. Among the sources of stress, parents' distrust of the child significantly correlated with commitment of one criminal offence (F = 2.8618, p < 0.05), and child's punishment (abuse) with a higher number of criminal offences (F = 3.1539, p < 0.05). Criminal activity of children and adolescents is significantly associated with their history of stress exposure over the last two years of life. The higher the stress severity, the greater the rate of delinquency.  相似文献   
72.
Pyruvate kinase M2 (PKM2) regulates the final step of glycolysis levels that are correlated with the sensitivity of anticancer chemotherapeutic drugs. THP is one of the major drugs used in non‐muscle‐invasive bladder cancer instillation chemotherapy. However, low response ratio of THP (19.7%) treatment to human genitourinary tumours using collagen gel matrix has been observed. This study aims to investigate the effect of down‐regulation of PKM2 on THP efficiency. Via inhibitor or siRNA, the effects of reduced PKM2 on the efficiency of THP were determined in 2 human and 1 murine bladder cancer cell lines, using MTT, cologenic and fluorescence approaches. Molecular mechanisms of PKM2 on THP sensitization were explored by probing p‐AMPK and p‐STAT3 levels via WB. Syngeneic orthotopic bladder tumour model was applied to evaluate this efficiency in vivo, analysed by Kaplan‐Meier survival curves, body and bladder weights plus immunohistochemistric tumour biomarkers. PKM2 was overexpressed in bladder cancer cells and tissues, and down‐regulation of PKM2 enhanced the sensitivity of THP in vitro. Activation of AMPK is essential for THP to exert anti‐bladder cancer activities. On the other hand, down‐regulating PKM2 activates AMPK and inhibits STAT3, correlated with THP sensitivity. Compared with THP alone (400 μmol L?1, 50 μL), the combination with metformin (60 mmol L?1, 50 μL) stopped growth of bladder cancer completely in vivo (combination group VS normal group P = .078). Down‐regulating the expression of PKM2 enhances the anticancer efficiency of THP. This study provides a new insight for improving the chemotherapeutic effect of THP.  相似文献   
73.
DOG1, a Ca2+-activated Cl channel (CaCC), was identified in 2004 to be robustly expressed in gastrointestinal stromal tumors (GIST). It was rapidly included as a tumor marker in routine diagnostics, but the functional role remained unknown. CaCCs are important regulators of normal physiological functions, but also implicated in tumorigenesis, cancer progression, metastasis, cell migration, apoptosis, proliferation and viability in several malignancies. We therefore investigated whether DOG1 plays a role in the three latter in GIST by utilizing in vitro cell model systems. Confocal microscopy identified different subcellular localizations of DOG1 in imatinib-sensitive and imatinib-resistant cells. Electrophysiological studies confirmed that DOG1-specific pharmacological agents possess potent activating and inhibiting properties. Proliferation assays showed small effects up to 72 h, and flow cytometric analysis of adherent cells with 7-AAD/Annexin V detected no pharmacological effects on viable GIST cells. However, inhibition of DOG1 conveyed pro-apoptotic effects among early apoptotic imatinib-resistant cells. In conclusion, DOG1 generates Cl currents in GIST that can be regulated pharmacologically, with small effects on cell viability and proliferation in vitro. Inhibition of DOG1 might act pro-apoptotic on some early apoptotic GIST cell populations. Further studies are warranted to fully illuminate the function of DOG1 and its potential as therapeutic target.  相似文献   
74.
Over the past two decades, RNA catalysis has become a major topic of research. On the one hand, naturally occurring ribozymes have been extensively investigated concerning their structure and functional mechanisms. On the other hand, the knowledge gained from these studies has been used to engineer ribozyme variants with novel properties. In addition to RNA engineering by means of rational design, powerful techniques for selection of ribozymes from large pools of random sequences were developed and have been widely used for the generation of functional nucleic acids. RNA as catalyst has been accompanied by DNA, and nowadays a large number of ribozymes and deoxyribozymes are available. The field of ribozyme generation and selection has been extensively reviewed. With respect to the field of biotechnology, RNA and DNA catalysts working on peptides or proteins, or which are designed to control protein synthesis, are of utmost importance and interest. Therefore, in this review, we will focus on engineered nucleic acid catalysts for peptide synthesis and modification as well as for intracellular control of gene expression.  相似文献   
75.

Background

The software available to date for analyzing image sequences from time-lapse microscopy works only for certain bacteria and under limited conditions. These programs, mostly MATLAB-based, fail for microbes with irregular shape, indistinct cell division sites, or that grow in closely packed microcolonies. Unfortunately, many organisms of interest have these characteristics, and analyzing their image sequences has been limited to time consuming manual processing.

Results

Here we describe BactImAS – a modular, multi-platform, open-source, Java-based software delivered both as a standalone program and as a plugin for Icy. The software is designed for extracting and visualizing quantitative data from bacterial time-lapse movies. BactImAS uses a semi-automated approach where the user defines initial cells, identifies cell division events, and, if necessary, manually corrects cell segmentation with the help of user-friendly GUI and incorporated ImageJ application. The program segments and tracks cells using a newly-developed algorithm designed for movies with difficult-to-segment cells that exhibit small frame-to-frame differences. Measurements are extracted from images in a configurable, automated fashion and an SQLite database is used to store, retrieve, and exchange all acquired data. Finally, the BactImAS can generate configurable lineage tree visualizations and export data as CSV files. We tested BactImAS on time-lapse movies of Mycobacterium smegmatis and achieved at least 10-fold reduction of processing time compared to manual analysis. We illustrate the power of the visualization tool by showing heterogeneity of both icl expression and cell growth atop of a lineage tree.

Conclusions

The presented software simplifies quantitative analysis of time-lapse movies overall and is currently the only available software for the analysis of mycobacteria-like cells. It will be of interest to the community of both end-users and developers of time-lapse microscopy software.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2105-15-251) contains supplementary material, which is available to authorized users.  相似文献   
76.
In this study, we investigated the cause and origin of fragrance in NERICA1, a fragrant rice inbred line developed from an interspecific cross between two non-fragrant parents. The genetic cause of fragrance in NERICA1 was found to be due to a previously reported mutation in the BADH2 gene, the same allele responsible for the majority of modern fragrant rice varieties. Haplotype analysis around the BADH2 gene in NERICA1, its parents, and 95 other varieties carrying the badh2.1 allele identified the source of the badh2.1 allele in NERICA1 was a fragrant tropical japonica variety, WAB638-1, which had been growing in the vicinity of the NERICA1 nursery during varietal development. The allele-specific marker for the badh2.1 allele consistently predicted fragrance in the diverse African germplasm tested, making it very useful for marker-assisted breeding of fragrant rice varieties in Africa.  相似文献   
77.
All patients who suffered from the acute coronary syndrome in western Herzegovina over the fifteen year period (1987-2001) are included in this retrospective epidemiological study. The population that was undertaken by the study is relative stabile and did not emigrate during the war period. The study compared the time before the war (1987-1991), during the war (1992-1996) and after the war (1997-2001). The data were acquired from the archives of the patients of the Mostar hospital and Clinical hospital Split during the war period. A total of 2022 acute coronary syndrome patients were found, 1305 men and 717 women. More patients were treated during the war compared to the time before the war for both male and female patients (p<0.0005). During the after-war period the number of treated patients was greater (p< 0.0005) compared to the war-time for both sexes. The comparison of the after-war period and the pre-war period reveals a statistically significant difference as the number of treated patients (male and female) is larger in the after-war period. The number of patient who are 65 years old and older than that is greater, and that is statistically significant (p= 0.0005.). We can conclude that the stress caused by the war and other factors have influenced a larger number of treated patients of acute coronary syndrome. Therefore, further epidemiological researches of acute coronary syndrome with the accent on prevention and treatment are needed.  相似文献   
78.
Acute colonic ischemia is the common cause of colitis in elderly population. However, isolated ischemic necrosis of cecum is rare entity, often associated with variety of conditions. Here we present a case of a 73-year old woman with a past history of hypertension presented with clinical symptoms of right lower quadrant abdominal pain and tenderness localized to the right lower quadrant, guarding and rebound tenderness. With diagnosis of acute appendicitis, the patient underwent laparoscopy where the cecal partial necrosis was discovered. Necrotic area of cecum was excised using two endoscopic cutters and laparoscopic appendectomy was performed. Pathologist report showed thrombosis of vessels and necrosis of entire cecal wall. The patient completely recovered without any surgical complications. This is the first case of partial cecum necrosis laparoscopicaly managed and with a partial cecal resection only.  相似文献   
79.
Forjan DM  Kontrec D  Vinković V 《Chirality》2006,18(10):857-869
The replacement of the N-H hydrogen of the secondary amide-tethered Pirkle-concept N-(3,5-dinitrobenzoyl)-L-leucine derived chiral stationary phase with various pi-basic or aliphatic groups improved the chiral discrimination ability of new chiral stationary phases, based on the leucine- or alanine-derived chiral selector, for the enantiomers of various racemic neutral analytes with amide functional groups. Retention times decreased while separation and resolution factors increased, thus proving the role of pi-donor aromatic unit as an electron-rich shield in the front of a silica surface. In general, chiral stationary phase (CSP) 5 with the 3,5-dimethylphenyl unit showed best performance, while CSP 3, with phenyl unit, and CSP 7, with 1-naphthyl unit in the tertiary amide connecting tether, were less efficient.  相似文献   
80.
This study investigated the effect of a skill-based training program on measurements of skill and physical fitness in talent-identified volleyball players. Twenty-six talented junior volleyball players (mean +/- SE age, 15.5 +/- 0.2 years) participated in an 8-week skill-based training program that included 3 skill-based court sessions per week. Skills sessions were designed to develop passing, setting, serving, spiking, and blocking technique and accuracy as well as game tactics and positioning skills. Coaches used a combination of technical and instructional coaching, coupled with skill-based games to facilitate learning. Subjects performed measurements of skill (passing, setting, serving, and spiking technique and accuracy), standard anthropometry (height, standing-reach height, body mass, and sum of 7 skinfolds), lower-body muscular power (vertical jump, spike jump), upper-body muscular power (overhead medicine-ball throw), speed (5- and 10-m sprint), agility (T-test), and maximal aerobic power (multistage fitness test) before and after training. Training induced significant (p < 0.05) improvements in spiking, setting, and passing accuracy and spiking and passing technique. Compared with pretraining, there were significant (p < 0.05) improvements in 5- and 10-m speed and agility. There were no significant differences between pretraining and posttraining for body mass, skinfold thickness, lower-body muscular power, upper-body muscular power, and maximal aerobic power. These findings demonstrate that skill-based volleyball training improves spiking, setting, and passing accuracy and spiking and passing technique, but has little effect on the physiological and anthropometric characteristics of players.  相似文献   
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