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121.
The chemical composition of fatty acid methyl esters (FAMEs) from seeds of S. thymbra and S. cuneifolia were analyzed by GC/MS. 7 FAMEs were identified from the seeds of S. thymbra mainly as 9-octadecenoic acid methyl ester (43.9%), hexadecanoic acid methyl ester (11.4%), 9,12,15-octadecatrienoic acid methyl ester (Z,Z,Z) (30.2%), and octadecanoic acid methyl ester (14.1%), while from the seed of S. cuneifolia 10 FAMEs were obtained with the main components, similar to S. thymbra. These were identified as 9-octadecenoic acid methyl ester (10.1%), hexadecanoic acid methyl ester (methyl palmitate, 34.6%), 9,12,15-octadecatrienoic acid methyl ester (Z,Z,Z) (6.3%) and octadecanoic acid methyl ester (1.8%).  相似文献   
122.
In cardiomyoplasty, the latissimus dorsi muscle is lifted on its primary neurovascular pedicle and wrapped around a failing heart. After 2 weeks, it is trained for 6 weeks using chronic electrical stimulation, which transforms the latissimus dorsi muscle into a fatigue-resistant muscle that can contract in synchrony with the beating heart without tiring. In over 600 cardiomyoplasty procedures performed clinically to date, the outcomes have varied. Given the data obtained in animal experiments, the authors believe these variable outcomes are attributable to distal latissimus dorsi muscle flap necrosis. The aim of the present study was to investigate whether the chronic electrical stimulation training used to transform the latissimus dorsi muscle into fatigue-resistant muscle could also be used to induce angiogenesis, increase perfusion, and thus protect the latissimus dorsi muscle flap from distal necrosis. After 14 days of chronic electrical stimulation (10 Hz, 330 microsec, 4 to 6 V continuous, 8 hours/day) of the right or left latissimus dorsi muscle (randomly selected) in 11 rats, both latissimus dorsi muscles were lifted on their thoracodorsal pedicles and returned to their anatomical beds. Four days later, the resulting amount of distal flap necrosis was measured. Also, at predetermined time intervals throughout the experiment, muscle surface blood perfusion was measured using scanning laser Doppler flowmetry. Finally, latissimus dorsi muscles were excised in four additional stimulated rats, to measure angiogenesis (capillary-to-fiber ratio), fiber type (oxidative or glycolytic), and fiber size using histologic specimens. The authors found that chronic electrical stimulation (1) significantly (p < 0.05) increased angiogenesis (mean capillary-to-fiber ratio) by 82 percent and blood perfusion by 36 percent; (2) did not reduce the amount of distal flap necrosis compared with nonchronic electrical stimulation controls (29 +/- 5.3 percent versus 26.6 +/- 5.1 percent); (3) completely transformed the normally mixed (oxidative and glycolytic) fiber type distribution into all oxidative fibers; and (4) reduced fiber size in the proximal and middle but not in the distal segments of the flap. Despite the significant increase in angiogenesis and blood perfusion, distal latissimus dorsi muscle flap necrosis did not decrease. This might be because of three reasons: first, the change in muscle metabolism from anaerobic to aerobic may have rendered the muscle fibers more susceptible to ischemia. Second, because of the larger diameter of the distal fibers in normal and stimulated latissimus dorsi muscle, the diffusion distance for oxygen to the center of the distal fibers is increased, making fiber survival more difficult. Third, even though angiogenesis was significantly increased in the flap, cutting all but the single vascular pedicle resulted in the newly formed capillaries not receiving enough blood to provide nourishment to the distal latissimus dorsi muscle. The authors' findings indicate that chronic electrical stimulation as tested in these experiments could not be used to prevent distal latissimus dorsi muscle flap ischemia and necrosis in cardiomyoplasty.  相似文献   
123.
Clopidogrel is widely used in cardiovascular medicine, and is believed to play an important role in the pathogenesis of many cardiovascular disease processes. In particular, patients undergoing coronary stenting, who are commonly treated with clopidogrel, are candidates for in-stent restenosis. This is mainly caused by neointimal hyperplasia, so it is important to consider whether clopidogrel affects neointimal hyperplasia via apoptosis. Lymphocytes, especially T-cells, are known to play a key role in the initiation and formation of atherosclerotic plaques. The aim of this study was to investigate the effect of clopidogrel on human lymphocyte apoptosis, using a DNA fragmentation assay.  相似文献   
124.
Hirsutism is a clinical condition commonly encountered in the practice of primary care medicine. The etiology and the age of the patient when it occurs vary widely. Causes range from a basic illness or condition (drug exposure, smoking, idiopathic, and obesity) to complex and serious diseases (Cushing's syndrome, neoplasms, congenital adrenal hyperplasia, insulin-resistance syndromes, hyperprolactinemia, polycystic ovary syndrome, and hyperthecosis). Hirsutism may appear in childhood as well as in older persons. Some drugs (oral contraceptives, L-thyroxine, danazol, and diazoxide), tobacco smoke, some syndromes (polycystic ovary syndrome, obesity, insulin resistance, hyperprolactinemia, hyperthecosis, congenital adrenal hyperplasia, and idiopathic), and some neoplasms (adrenal or ovarian) may lead to hirsutism. The most frequently defined "causes" of hirsutism are polycystic ovary syndrome and idiopathic hirsutism. In hirsutism of gradual onset, hyperprolactinemia, insulin-resistance syndromes, hyperthecosis, polycystic ovary syndrome, and idiopathic hirsutism may be responsible. Cushing's syndrome, neoplasms, and congenital adrenal hyperplasia should be suspected if there has been rapid onset.  相似文献   
125.
126.
TLRs constitute an essential family of pattern recognition molecules that, through direct recognition of conserved microbial components, initiate inflammatory responses following infection. In this role, TLR1 enables host responses to a variety of bacteria, including pathogenic species of mycobacteria. In this study, we report that I602S, a common single nucleotide polymorphism within TLR1, is associated with aberrant trafficking of the receptor to the cell surface and diminished responses of blood monocytes to bacterial agonists. When expressed in heterologous systems, the TLR1 602S variant, but not the TLR1 602I variant, exhibits the expected deficiencies in trafficking and responsiveness. Among white Europeans, the 602S allele represents the most common single nucleotide polymorphism affecting TLR function identified to date. Surprisingly, the 602S allele is associated with a decreased incidence of leprosy, suggesting that Mycobacterium leprae subverts the TLR system as a mechanism of immune evasion.  相似文献   
127.
The aim of the present study is to investigate the spatial and bathymetric distribution of demersal trawl discards in the Turkish coast of the Aegean Sea. Trawl hauls were performed in the legal trawling areas of the Turkish coast of the Aegean Sea (Çanakkale, Foça, Karaburun, S??ac?k, Güllük) between 2010 and 2012 by commercial trawlers. Depth of the trawl hauls ranged from 30?m in the south to 450?m in the north. As a result of 311 trawl samples, 200 species belonging to eight taxonomic groups (Porifera, Cnidaria, Annelida, Arthropoda, Mollusca, Echinodermata, Tunicata, Chordata) were identified. The changes in species composition based on depth and region were determined to be statistically significant. It was found that species composition distinctly changed around 200?m. In a regional assessment it was determined that the Turkish coast of the Aegean Sea is divided into three sub-regions, i.e. Çanakkale, Foça-Karaburun-S??ac?k and Güllük. The results of similar studies conducted in the Mediterranean were investigated and compared with the findings of this study.  相似文献   
128.
Molecular and Cellular Biochemistry - White adipose tissue (WAT) is the bulk of fatty tissues in humans. Enhancing the potential of WAT-derived stem cells (WATDCs) to generate cardiomyocytes may...  相似文献   
129.
Statins provide strong clinical benefits via reducing stroke deaths, and they are also considered for tumor reduction and chemo-sensitization. High dose atorvastatin in adults (80 mg daily, approx. 1 mg/kg) is proven to afford greater protection against cardiac deaths than does a standard lipid-lowering dose in coronary syndrome. For cancer trials, mega doses up to 30 mg/kg have been used for short term treatments but neither a high nor a mega-dose of atorvastatin has been tested for long term cardiac safety. This may be of special concern, since some animal studies showed deleterious effects of statins on cardiac tissue, which may be related with coenzymeQ (CoQ) depletion. We performed an electron microscopic analysis of rat hearts after low, high-or mega-dose atorvastatin therapy and with or without MNU (methyl-nitrosourea)-stress. MNU + daily high dose atorvastatin treatment for 13 months did not produce severe cardiac toxicity with CoQ. However, at mega doses (30 mg/kg) and with MNU, mitochondrial damage and myofibrillary disintegration was obvious. Strong proliferation of mitochondria under high dose atorvastatin therapy with CoQ may explain the lack of cardiotoxicity; and this finding seems to parallel recent data that statins induce HNF-4 and PPAR-alpha, both responsible for mitochondria-proliferation. Employment of statins for tumor chemo-sensitization at high-dosage and for long term treatments may require strategies to direct the mevalonate-entry differentially into cardiac and tumor cells and to develop a protocol analogous to folic acid salvage of methotrexate toxicity.  相似文献   
130.
Removal and repair of DNA damage by the nucleotide excision repair pathway requires two sequential incision reactions, which are achieved by the endonuclease UvrC in eubacteria. Here, we describe the crystal structure of the C-terminal half of UvrC, which contains the catalytic domain responsible for 5' incision and a helix-hairpin-helix-domain that is implicated in DNA binding. Surprisingly, the 5' catalytic domain shares structural homology with RNase H despite the lack of sequence homology and contains an uncommon DDH triad. The structure also reveals two highly conserved patches on the surface of the protein, which are not related to the active site. Mutations of residues in one of these patches led to the inability of the enzyme to bind DNA and severely compromised both incision reactions. Based on our results, we suggest a model of how UvrC forms a productive protein-DNA complex to excise the damage from DNA.  相似文献   
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