全文获取类型
收费全文 | 187篇 |
免费 | 7篇 |
出版年
2024年 | 1篇 |
2023年 | 3篇 |
2022年 | 5篇 |
2021年 | 8篇 |
2020年 | 10篇 |
2019年 | 4篇 |
2018年 | 3篇 |
2017年 | 6篇 |
2016年 | 6篇 |
2015年 | 13篇 |
2014年 | 8篇 |
2013年 | 9篇 |
2012年 | 15篇 |
2011年 | 19篇 |
2010年 | 9篇 |
2009年 | 9篇 |
2008年 | 11篇 |
2007年 | 15篇 |
2006年 | 5篇 |
2005年 | 8篇 |
2004年 | 5篇 |
2003年 | 4篇 |
2002年 | 6篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1994年 | 2篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1977年 | 2篇 |
1972年 | 1篇 |
1964年 | 1篇 |
排序方式: 共有194条查询结果,搜索用时 15 毫秒
51.
Background
The Quality and Outcomes Framework (QOF), a major pay-for-performance programme, was introduced into United Kingdom primary care in April 2004. The impact of this programme on disparities in health care remains unclear. This study examines the following questions: has this pay for performance programme improved the quality of care for coronary heart disease, stroke and hypertension in white, black and south Asian patients? Has this programme reduced disparities in the quality of care between these ethnic groups? Did general practices with different baseline performance respond differently to this programme?Methodology/Principal Findings
Retrospective cohort study of patients registered with family practices in Wandsworth, London during 2007. Segmented regression analysis of interrupted time series was used to take into account the previous time trend. Primary outcome measures were mean systolic and diastolic blood pressure, and cholesterol levels. Our findings suggest that the implementation of QOF resulted in significant short term improvements in blood pressure control. The magnitude of benefit varied between ethnic groups with a statistically significant short term reduction in systolic BP in white and black but not in south Asian patients with hypertension. Disparities in risk factor control were attenuated only on few measures and largely remained intact at the end of the study period.Conclusions/Significance
Pay for performance programmes such as the QOF in the UK should set challenging but achievable targets. Specific targets aimed at reducing ethnic disparities in health care may also be needed. 相似文献52.
Type 2 diabetes mellitus is a growing, worldwide public health concern. Recent growth has been particularly dramatic in the states of The Co-operation Council for the Arab States of the Gulf (GCC), and these and other developing economies are at particular risk. We aimed to systematically review the quality of control of type 2 diabetes in the GCC, and the nature and efficacy of interventions. We identified 27 published studies for review. Studies were identified by systematic database searches. Medline and Embase were searched separately (via Dialog and Ovid, respectively; 1950 to July 2010 (Medline), and 1947 to July 2010 (Embase)) on 15/07/2009. The search was updated on 08/07/2010. Terms such as diabetes mellitus, non-insulin-dependent, hyperglycemia, hypertension, hyperlipidemia and Gulf States were used. Our search also included scanning reference lists, contacting experts and hand-searching key journals. Studies were judged against pre-determined inclusion/exclusion criteria, and where suitable for inclusion, data extraction/quality assessment was achieved using a specifically-designed tool. All studies wherein glycaemic-, blood pressure- and/or lipid- control were investigated (clinical and/or process outcomes) were eligible for inclusion. No limitations on publication type, publication status, study design or language of publication were imposed. We found the extent of control to be sub-optimal and relatively poor. Assessment of the efficacy of interventions was difficult due to lack of data, but suggestive that more widespread and controlled trial of secondary prevention strategies may have beneficial outcomes. We found no record of audited implementation of primary preventative strategies and anticipate that controlled trial of such strategies would also be useful. 相似文献
53.
Regie?Lyn?P. Santos-Cortez Kwanghyuk Lee Zahid Azeem Patrick?J. Antonellis Lana?M. Pollock Saadullah Khan Irfanullah Paula?B. Andrade-Elizondo Ilene Chiu Mark?D. Adams Sulman Basit Joshua?D. Smith University of Washington Center?for?Mendelian Genomics Deborah?A. Nickerson Brian?M. McDermott Jr. Wasim Ahmad Suzanne?M. Leal 《American journal of human genetics》2013,93(1):132-140
Previously, DFNB89, a locus associated with autosomal-recessive nonsyndromic hearing impairment (ARNSHI), was mapped to chromosomal region 16q21–q23.2 in three unrelated, consanguineous Pakistani families. Through whole-exome sequencing of a hearing-impaired individual from each family, missense mutations were identified at highly conserved residues of lysyl-tRNA synthetase (KARS): the c.1129G>A (p.Asp377Asn) variant was found in one family, and the c.517T>C (p.Tyr173His) variant was found in the other two families. Both variants were predicted to be damaging by multiple bioinformatics tools. The two variants both segregated with the nonsyndromic-hearing-impairment phenotype within the three families, and neither mutation was identified in ethnically matched controls or within variant databases. Individuals homozygous for KARS mutations had symmetric, severe hearing impairment across all frequencies but did not show evidence of auditory or limb neuropathy. It has been demonstrated that KARS is expressed in hair cells of zebrafish, chickens, and mice. Moreover, KARS has strong localization to the spiral ligament region of the cochlea, as well as to Deiters’ cells, the sulcus epithelium, the basilar membrane, and the surface of the spiral limbus. It is hypothesized that KARS variants affect aminoacylation in inner-ear cells by interfering with binding activity to tRNA or p38 and with tetramer formation. The identification of rare KARS variants in ARNSHI-affected families defines a gene that is associated with ARNSHI. 相似文献
54.
55.
56.
57.
Azevedo C Casal G São Clemente SC Lopes LM Matos P Abdel-Baki AA Oliveira E Matos E 《Memórias do Instituto Oswaldo Cruz》2011,106(5):557-561
Myxidium volitans sp. nov. (Myxozoa: Myxidiidae) parasitizing the hypertrophied green-brownish gallbladder of the teleost Dactylopterus volitans, collected in the Atlantic coast near Niterói, Brazil was described based on ultrastructural studies. The spores were fusiform, sometimes slightly crescent-shaped on average 21.7 ± 0.3 μm (mean ± standard deviation) (n = 50) long and 5.6 ± 0.4 μm (n = 30) wide. The spore wall was thin and smooth, comprising two equally-sized valves joined by a hardly visible sutural ridge. Spores containing two pyriform polar capsules (PC) (5.0 ± 0.4 × 2.3 ± 0.3 μm) (n = 30) are situated in each extremity of the spore. The PC wall was composed of hyaline layer (0.20-0.29 μm thick) and by a thin external granular layer. Each PC contains a polar filament (PF) with irregular arrangements that was projected from its apical region to the bases of PC and coiled laterally from bases to the tip of PC. Some regular striations and S-like structures in the periphery of the PFs with four-five irregular sections were observed. Based on the spore morphology, ultrastructural differences and the specificity of the host we describe this parasite as a new myxosporidian, named M. volitans sp. nov. 相似文献
58.
Marvania B Lee PC Chaniyara R Dong H Suman S Kakadiya R Chou TC Lee TC Shah A Su TL 《Bioorganic & medicinal chemistry》2011,19(6):1987-1998
A series of N-mustard-quinazoline conjugates was synthesized and subjected to antitumor studies. The N-mustard pharmacophore was attached at the C-6 of the 4-anilinoquinazolines via a urea linker. To study the structure-activity relationships of these conjugates, various substituents were introduced to the C-4 anilino moiety. The preliminary antitumor studies revealed that these agents exhibited significant antitumor activity in inhibiting various human tumor cell growths in vitro. Compounds 21b, 21g, and 21h were selected for further antitumor activity evaluation against human breast carcinoma MX-1 and prostate PC-3 xenograft in animal model. These agents showed 54-75% tumor suppression with low toxicity (5-7% body-weight changes). We also demonstrate that the newly synthesized compounds are able to induce DNA cross-linking through alkaline agarose gel shift assay and inhibited cell cycle arrest at G2/M phase. 相似文献
59.
Two phytochromes, CphA and CphB, from the cyanobacterium Calothrix PCC7601, with similar size (768 and 766 amino acids) and domain structure, were investigated for the essential length of
their protein moiety required to maintain the spectral integrity. Both proteins fold into PAS-, GAF-, PHY-, and Histidine-kinase
(HK) domains. CphA binds a phycocyanobilin (PCB) chromophore at a “canonical” cysteine within the GAF domain, identically
as in plant phytochromes. CphB binds biliverdin IXα at cysteine24, positioned in the N-terminal PAS domain. The C-terminally
located HK and PHY domains, present in both proteins, were removed subsequently by introducing stop-codons at the corresponding
DNA positions. The spectral properties of the resulting proteins were investigated. The full-length proteins absorb at (CphA)
663 and 707 nm (red-, far red-absorbing P
r and P
fr forms of phytochromes) and at (CphB) 704 and 750 nm. Removal of the HK domains had no effect on the absorbance maxima of
the resulting PAS–GAF–PHY constructs (CphA: 663/707 nm, CphB: 704/750 nm, P
r/P
fr, respectively). Further deletion of the “PHY” domains caused a blue-shift of the P
r and P
fr absorption of CphA (λ
max: 658/698 nm) and increased the amount of unproperly folded apoprotein, seen by a reduced capability to bind the chromophore
in photoconvertible manner. In CphB, however, it practically impaired the formation of P
fr, i.e., showing a very low oscillator strength absorption band, whereas the P
r form remains unchanged (702 nm). This finding clearly indicates a different interaction between domains in the “typical”,
PCB binding and in the biliverdin-binding phytochromes, and demonstrates a loss of oscillator strength for the latter, most
probably due to a strong conformational distortion of the chromophore in the CphB P
fr form.
Proceedings of the XVIII Congress of the Italian Society of Pure and Applied Biophysics (SIBPA), Palermo, Sicily, September
2006. 相似文献
60.
Murgida DH von Stetten D Hildebrandt P Schwinté P Siebert F Sharda S Gärtner W Mroginski MA 《Biophysical journal》2007,93(7):2410-2417
The resonance Raman spectra of the Pr state of the N-terminal 65-kDa fragment of plant phytochrome phyA have been measured and analyzed in terms of the configuration and conformation of the tetrapyrroles methine bridges. Spectra were obtained from phyA adducts reconstituted with the natural chromophore phytochromobilin as well as phycocyanobilin and its isotopomers labeled at the terminal methine bridges through (13)C/(12)C and D/H substitution. Upon comparing the resonance Raman spectra of the various phyA adducts, it was possible to identify the bands that originate from normal modes dominated by the stretching coordinates of the terminal methine bridges A-B and C-D. Quantum chemical calculations of the isolated tetrapyrroles reveal that these modes are sensitive indicators for the methine bridge configuration and conformation. For all phyA adducts, the experimental spectra of Pr including this marker band region are well reproduced by the calculated spectra obtained for the ZZZasa configuration. In contrast, there are substantial discrepancies between the experimental spectra and the spectra calculated for the ZZZssa configuration, which has been previously shown to be the chromophore geometry in the Pr state of the bacterial, biliverdin-binding phytochrome from Deinococcus radiodurans (Wagner, J. R., J. S. Brunzelle, K. T. Forest, R. D. Vierstra. 2005. Nature. 438:325-331). The results of this work, therefore, suggest that plant and bacterial (biliverdin-binding) phytochromes exhibit different structures in the parent state although the mechanism of the photoinduced reaction cycle may be quite similar. 相似文献