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101.
102.
A biological microelectromechanical system (BioMEMS) device was designed to study complementary mitochondrial parameters important in mitochondrial dysfunction studies. Mitochondrial dysfunction has been linked to many diseases, including diabetes, obesity, heart failure and aging, as these organelles play a critical role in energy generation, cell signaling and apoptosis. The synthesis of ATP is driven by the electrical potential across the inner mitochondrial membrane and by the pH difference due to proton flux across it. We have developed a tool to study the ionic activity of the mitochondria in parallel with dielectric measurements (impedance spectroscopy) to gain a better understanding of the properties of the mitochondrial membrane. This BioMEMS chip includes: 1) electrodes for impedance studies of mitochondria designed as two- and four-probe structures for optimized operation over a wide frequency range and 2) ion-sensitive field effect transistors for proton studies of the electron transport chain and for possible monitoring other ions such as sodium, potassium and calcium. We have used uncouplers to depolarize the mitochondrial membrane and disrupt the ionic balance. Dielectric spectroscopy responded with a corresponding increase in impedance values pointing at changes in mitochondrial membrane potential. An electrical model was used to describe mitochondrial sample’s complex impedance frequency dependencies and the contribution of the membrane to overall impedance changes. The results prove that dielectric spectroscopy can be used as a tool for membrane potential studies. It can be concluded that studies of the electrochemical parameters associated with mitochondrial bioenergetics may render significant information on various abnormalities attributable to these organelles. 相似文献
103.
Foltyn W Kos-Kudła B Siemińska L Zemczak A Strzelczyk J Marek B Kajdaniuk D Nowak M Borowska M Jurecka-Lubienicka B 《Endokrynologia Polska》2006,57(2):160-165
Neuroendocrine tumors are frequently associated with other primary malignancies. Plasmablastic lymphoma is a rare, aggressive neoplasm, derived from large B-cell, associated with human immunodeficiency virus infection. Plasmablastic lymphoma cells share many cytomorphologic and immunophenotypic features with plasmablastic cells, causing some diagnostic problems. We present a unique case of coexisting two very uncommon neoplasms: plasmablastic lymphoma and neuroendocrine carcinoma in 54-years-old men. This is the first report of caecum localization of plasmablastic lymphoma. Presented case images diagnostic problems in rare neoplasms. 相似文献
104.
Gauthier JY Black WC Courchesne I Cromlish W Desmarais S Houle R Lamontagne S Li CS Massé F McKay DJ Ouellet M Robichaud J Truchon JF Truong VL Wang Q Percival MD 《Bioorganic & medicinal chemistry letters》2007,17(17):4929-4933
Highly potent, selective, and bioavailable inhibitors of human, mouse, or rat cathepsin S are described. The key structural features combine a sulfonyl moiety attached to a large group in P2 and a small substituent in P3. 相似文献
105.
106.
Zinc and cadmium analysis in human prostate neoplasms 总被引:4,自引:0,他引:4
Magdalena Brys Agnieszka D. Nawrocka Eügeniüsz MlekoŚ Cezary Zydek Marek Foksinski Andrzej Barecki Wanda M. Krajewska 《Biological trace element research》1997,59(1-3):145-152
The objective of this study was to test the hypothesis that prostatic cancer is associated with the changes of zinc (Zn) and
cadmium (Cd) concentration. Normal prostate, benign prostatic hyperplasia (BPH), and prostatic carcinoma (PCA) were analyzed
for Zn and Cd by atomic absorption spectrometry. Cd level was measured using a graphite furnace and Zn level was measured
by flame mode. Metal content was assessed in whole tissues and in nuclear, plasma membrane, and cytosolic fractions. An increase
of Zn content in BPH, but a decrease in PCA as compared to normal tissue, was observed. Cd concentration appeared to be higher
in BPH and PCA than in normal tissue. No correlation between Zn and Cd level was found in BPH specimens obtained from the
same patients. Probability values ofp ≤0.05 were considered to indicate significant differences. Obtained results seem to support the hypothesis of Cd carcinogenicity
and preventing function of Zn in prostatic cancer. Plasma membrane fraction corresponding to lysosomal, mitochondrial, and
microsomal subcellular compartments are probably critical in Zn and Cd participation in human prostate neoplasms. 相似文献
107.
Carla Maria P. Ribeiro Harry Hurd Yichao Wu Mary E. B. Martino Lisa Jones Brian Brighton Richard C. Boucher Wanda K. O'Neal 《PloS one》2009,4(6)
Prolonged macrolide antibiotic therapy at low doses improves clinical outcome in patients affected with diffuse panbronchiolitis and cystic fibrosis. Consensus is building that the therapeutic effects are due to anti-inflammatory, rather than anti-microbial activities, but the mode of action is likely complex. To gain insights into how the macrolide azithromycin (AZT) modulates inflammatory responses in airways, well-differentiated primary cultures of human airway epithelia were exposed to AZT alone, an inflammatory stimulus consisting of soluble factors from cystic fibrosis airways, or AZT followed by the inflammatory stimulus. RNA microarrays were conducted to identify global and specific gene expression changes. Analysis of gene expression changes revealed that the AZT treatment alone altered the gene profile of the cells, primarily by significantly increasing the expression of lipid/cholesterol genes and decreasing the expression of cell cycle/mitosis genes. The increase in cholesterol biosynthetic genes was confirmed by increased filipin staining, an index of free cholesterol, after AZT treatment. AZT also affected genes with inflammatory annotations, but the effect was variable (both up- and down-regulation) and gene specific. AZT pretreatment prevented the up-regulation of some genes, such as MUC5AC and MMP9, triggered by the inflammatory stimulus, but the up-regulation of other inflammatory genes, e.g., cytokines and chemokines, such as interleukin-8, was not affected. On the other hand, HLA genes were increased by AZT. Notably, secreted IL-8 protein levels did not reflect mRNA levels, and were, in fact, higher after AZT pretreatment in cultures exposed to the inflammatory stimulus, suggesting that AZT can affect inflammatory pathways other than by altering gene expression. These findings suggest that the specific effects of AZT on inflamed and non-inflamed airway epithelia are likely relevant to its clinical activity, and their apparent complexity may help explain the diverse immunomodulatory roles of macrolides. 相似文献
108.
Blizzard TA Gude C Morgan JD Chan W Birzin ET Mojena M Tudela C Chen F Knecht K Su Q Kraker B Mosley RT Holmes MA Sharma N Fitzgerald PM Rohrer SP Hammond ML 《Bioorganic & medicinal chemistry letters》2006,16(4):834-838
A series of 19-substituted androstenediol derivatives was prepared. Some of the novel analogs were surprisingly potent and selective ligands for ER-beta. 相似文献
109.
In developed societies, the post-menopausal period covers approximately one third of a woman's life. The deficit of oestrogens observed during the post-menopausal period significantly affects the course of many metabolic processes, causing a number of diseases and in consequence diminishing quality of life. Among others, bones belong to oestrogen-dependent tissues. The deficit of the protective influence of oestrogens compromises the dynamic balance of the bone transformation process towards resorption, thus reducing bone mass and quality, while increasing the risk of low-energy fractures. In recent years, differing views on the application of oestrogen/gestagen therapy have reached the level of controversy. The results of numerous clinical studies are far from unequivocal, with the whole subject one of heated debate. It has been confirmed that hormonal therapy prevents bone quality deterioration, while opening a protective umbrella around the bone, reducing the risk of osteoporotic fractures. A rational approach to weighing possible advantages against possible risks and a thorough evaluation of a patient's health condition allows for optimal therapy selection. 相似文献
110.
Anorexia nervosa (AN) has in recent years become considerably more common. The disease primarily affects girls and young women, and also boys and young men. AN is a risk factor for secondary osteoporosis. AN-related metabolic disturbances lead to diminished bone quality and increased risk of fractures. The consequences of low energy fractures are the main causes of death in women with AN. Hormonal disturbances (e.g. hypoestrogenism, increased levels of ghrelin and Y peptide, changes in leptin and endocannabinoid levels), as well as the mechanisms involved in bone resorption (RANK/RANKL/OPG), are considered to be of great importance for anorectic bone quality. The risk of osteoporotic, non-vertebral fractures in AN patients is significantly higher than in healthy women. An improvement of bone mineral density is possible after substantial body mass increase. Weight loss, in conjunction with a well-balanced, controlled diet, is the key to correct peak bone mass levels, and diminishes the risk of osteoporosis with its consequence of low energy bone fractures. (Pol J Endocrinol 2011; 62 (1): 45-47). 相似文献