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81.
T-cell distribution in two different segments of the equine endometrium 6 and 48 hours after insemination 总被引:1,自引:0,他引:1
The T-cell response after the introduction of semen into the uterine cavity in the mare was studied by examining, immunohistochemically, the distribution of helper T-cells (CD4+) and cytotoxic T-cells (CD8+) in endometrial biopsy specimens. Endometrial tissue samples were obtained from twenty-five gynecologically healthy mares during estrus before and 6 or 48 h after deposition of a single dose of stallion semen. An increase (P=0.04) in the number of helper T-cells (CD4+) compared to pre-insemination values was observed in the uterine body in both groups, 6 and 48 h, after insemination. No significant variations in numbers of CD8+ cells were recorded either 6 or 48 h after insemination. There seems to be an early (6 h) recruitment of helper T-cells to the equine endometrium after semen deposition, which might be related to the activation of the endometritis-like reaction seen as part of the equine uterine immune defense during estrus. 相似文献
82.
Vasoactive intestinal peptide (VIP) has potent protective activity against sepsis and increases the survival rate of septic rats and mice. The present study was planned to evaluate the effect of VIP on mast cell activity, histamine and methylhistamine levels and oxidative stress in the liver and kidneys of septic rats. The effect of VIP was compared to that of nitric oxide synthesis inhibition, previously tested extensively in septic shock models, with doubtful benefit. The present study showed that endotoxic shock did not lead to oxidative stress in either liver or kidney of the rats. On the other hand, mast cells, based on their location, displayed functional heterogeneity to the septic insults. VIP possibly modulated the specific reactions of the tissues to mediators released from mast cells during septic shock. The most prominent effect of VIP as compared to nitric oxide synthesis inhibition was related to mast cells. In conclusion, the prevention of mast cell reactivity by VIP could be a potential therapeutic strategy in controlling septic shock. 相似文献
83.
Game L Close J Stephens P Mitchell J Best S Rochette J Louis-dit-Sully C Riley J See CG Sanseau P Kearney L Bethel G Humphray S Dunham I Mungall A Thein SL 《Genomics》2000,64(3):264-276
Genetic studies have previously assigned a quantitative trait locus (QTL) for hemoglobin F and F cells to a region of approximately 4 Mb between the markers D6S408 and D6S292 on chromosome 6q23. An initial yeast artificial chromosome contig of 13 clones spanning this region was generated. Further linkage analysis of an extended kindred refined the candidate interval to 1-2 cM, and key recombination events now place the QTL within a region of <800 kb. We describe a high-resolution bacterial clone contig spanning 3 Mb covering this critical region. The map consists of 223 bacterial artificial chromosome (BAC) and 100 P1 artificial chromosome (PAC) clones ordered by sequence-tagged site (STS) content and restriction fragment fingerprinting with a minimum tiling path of 22 BACs and 1 PAC. A total of 194 STSs map to this interval of 3 Mb, giving an average marker resolution of approximately one per 15 kb. About half of the markers were novel and were isolated in the present study, including three CA repeats and 13 single nucleotide polymorphisms. Altogether 24 expressed sequence tags, 6 of which are unique genes, have been mapped to the contig. 相似文献
84.
Background
Heterocellular hereditary persistence of fetal hemoglobin (HPFH) is a common multifactorial trait characterized by a modest increase of fetal hemoglobin levels in adults. We previously localized a Quantitative Trait Locus for HPFH in an extensive Asian-Indian kindred to chromosome 6q23. As part of the strategy of positional cloning and a means towards identification of the specific genetic alteration in this family, a thorough annotation of the candidate interval based on a strategy ofin silico/ wet biology approach with comparative genomics was conducted. 相似文献85.
Tabata M Kurosawa H Kikuchi Y Hida W Ogawa H Okabe S Tun Y Hattori T Shirato K 《American journal of physiology. Regulatory, integrative and comparative physiology》2001,281(5):R1411-R1419
The purpose of this study was to examine our hypothesis that gamma-aminobutyric acid (GABA) in the nucleus tractus solitarii (NTS) may be related to the hypoxic ventilatory decline (HVD) and that chemoreceptor stimulation was essential to activate this mechanism. We used unanesthetized, freely moving rats in this study. An in vivo microdialysis technique was used to measure the extracellular GABA concentration ([GABA]o), and an in vivo microinjection technique was used to examine the effects of the GABA agonists and antagonists on the ventilation during hypoxia. The GABA agonists injected into the NTS attenuated the ventilation during hypoxia. By hypoxic exposure, [GABA]o was increased during the HVD. However, by carotid body denervation (CBD), this GABA increase was abolished. Although GABA antagonists microinjected into the NTS during the HVD phase significantly increased the depressed ventilation, this effect on the ventilation was abolished by CBD. These results suggest that the GABA in the NTS has a pivotal role in the HVD and that this mechanism is not activated without chemoreceptor stimulation. 相似文献
86.
Carcinoma in chronic pressure sores: a fulminant disease process 总被引:1,自引:0,他引:1
T Mustoe J Upton V Marcellino C J Tun A B Rossier H J Hachend 《Plastic and reconstructive surgery》1986,77(1):116-121
Four cases of squamous cell carcinoma arising from chronic pressure sores in paraplegic and tetraplegic patients are presented and the literature reviewed. These pressure-sore carcinomas are characterized by a shorter latency period and a fulminant clinical course with a very high metastatic rate. Very aggressive treatment including even hemicorporectomy must be considered if a cure is to be achieved. 相似文献
87.
Parveen Kaur Parmar Charlene C. Barina Sharon Low Kyaw Thura Tun Conrad Otterness Pue P. Mhote Saw Nay Htoo Saw Win Kyaw Nai Aye Lwin Cynthia Maung Naw Merry Moo Eh Kalu Shwe Oo Daniel Reh Nai Chay Mon Nakul Singh Ravi Goyal Adam K. Richards 《PloS one》2015,10(5)
BackgroundMyanmar transitioned to a nominally civilian parliamentary government in March 2011. Qualitative reports suggest that exposure to violence and displacement has declined while international assistance for health services has increased. An assessment of the impact of these changes on the health and human rights situation has not been published.ConclusionThis large survey of health and human rights demonstrates that two years after political transition, vulnerable populations of eastern Myanmar are less likely to experience human rights violations compared to previous surveys. However, access to health services remains constrained, and risk of disease and death remains higher than the country as a whole. Efforts to address these poor health indicators should prioritize support for populations that remain outside the scope of most formal government and donor programs. 相似文献
88.
Ali Tun? Tuncel Thorsten Ruppert Bei-Tzu Wang Jürgen Günther Okun Stefan K?lker Marina Alexandra Morath Sven Wolfgang Sauer 《PloS one》2015,10(6)
Maleic acid (MA) has been shown to induce Fanconi syndrome via disturbance of renal energy homeostasis, though the underlying pathomechanism is still under debate. Our study aimed to examine the pathomechanism underlying maleic acid-induced nephrotoxicity. Methylmalonic acid (MMA) is structurally similar to MA and accumulates in patients affected with methymalonic aciduria, a defect in the degradation of branched-chain amino acids, odd-chain fatty acids and cholesterol, which is associated with the development of tubulointerstitial nephritis resulting in chronic renal failure. We therefore used MMA application as a control experiment in our study and stressed hPTECs with MA and MMA to further validate the specificity of our findings. MMA did not show any toxic effects on proximal tubule cells, whereas maleic acid induced concentration-dependent and time-dependent cell death shown by increased lactate dehydrogenase release as well as ethidium homodimer and calcein acetoxymethyl ester staining. The toxic effect of MA was blocked by administration of single amino acids, in particular L-alanine and L-glutamate. MA application further resulted in severe impairment of cellular energy homeostasis on the level of glycolysis, respiratory chain, and citric acid cycle resulting in ATP depletion. As underlying mechanism we could identify disturbance of calcium homeostasis. MA toxicity was critically dependent on calcium levels in culture medium and blocked by the extra- and intracellular calcium chelators EGTA and BAPTA-AM respectively. Moreover, MA-induced cell death was associated with activation of calcium-dependent calpain proteases. In summary, our study shows a comprehensive pathomechanistic concept for MA-induced dysfunction and damage of human proximal tubule cells. 相似文献
89.
Jaeger JJ Soe AN Chavasseau O Coster P Emonet EG Guy F Lebrun R Maung A Aung Khyaw A Shwe H Thura Tun S Linn Oo K Rugbumrung M Bocherens H Benammi M Chaivanich K Tafforeau P Chaimanee Y 《PloS one》2011,6(4):e17065
For over a century, a Neogene fossil mammal fauna has been known in the Irrawaddy Formation in central Myanmar. Unfortunately, the lack of accurately located fossiliferous sites and the absence of hominoid fossils have impeded paleontological studies. Here we describe the first hominoid found in Myanmar together with a Hipparion (s.l.) associated mammal fauna from Irrawaddy Formation deposits dated between 10.4 and 8.8 Ma by biochronology and magnetostratigraphy. This hominoid documents a new species of Khoratpithecus, increasing thereby the Miocene diversity of southern Asian hominoids. The composition of the associated fauna as well as stable isotope data on Hipparion (s.l.) indicate that it inhabited an evergreen forest in a C3-plant environment. Our results enlighten that late Miocene hominoids were more regionally diversified than other large mammals, pointing towards regionally-bounded evolution of the representatives of this group in Southeast Asia. The Irrawaddy Formation, with its extensive outcrops and long temporal range, has a great potential for improving our knowledge of hominoid evolution in Asia. 相似文献
90.
Shanmuuga Sundaram Alice Matathia Jun Qian Jingming Zhang Ming-Ching Hsieh Tun Liu Richard Crowley Babita Parekh Qinwei Zhou 《MABS-AUSTIN》2011,3(6):505-512
Protein biopharmaceuticals, such as monoclonal antibodies (mAbs) are widely used for the prevention and treatment of various diseases. The complex and lengthy upstream and downstream production methods of the antibodies make them susceptible to physical and chemical modifications. Several IgG1 immunoglobulins are used as medical agents for the treatment of colon, breast and head and neck cancers, and at least four to eight isoforms exist in the products. The regulatory agencies understand the complex nature of the antibody molecules and allow the manufactures to set their own specifications for lot release, provided the safety and efficacy of the products are established in animal models prior to clinical trials. During the manufacture of a mAb product, we observed lot-to-lot variability in the isoform content and, although the variability is within the set specifications for lot release, made attempts to gain mechanistic insight by isolating and characterizing the individual isoforms. Matrix-assisted laser desorption/ionization (MALDI) and liquid chromatography (LC)/mass spectrometry (MS)/MS analyses of the isolated isoforms indicate that this variability is caused by sialic acid content, as well as truncation of C-terminal lysine of the individual isoforms. Sialidase and carboxypeptidase treatment of the product confirm the observations made by MALDI and LC/MS/MS.Key words: IgG1, isoforms, charge heterogeneity, monoclonal antibody, glycosylation, silaic acidMonoclonal antibodies (mAbs) are used as medical agents to treat a variety of diseases including cancer, cardiovascular diseases and blood disorders.1–3 Although a few IgG2 (e.g., panitumumab, denosumab) and IgG4 antibody molecules are in the market, most of the approved products are IgG1 molecules. IgG1 antibodies are glycoproteins with a conserved N-glycosylation site at Asn 297. Glycosylation influences the biological functions, such as antibody dependent cell-mediated cytotoxicity (ADCC) and complement dependent cytotoxicity (CDC) of the antibodies. The oligosaccharides present in the IgG1 molecules are heterogeneous due to the presence of various sugar residues, including sialic acid, galactose, N-acetylglucasmine and fucose residues. Molecular alterations in antibodies can take place at every stage of manufacturing: upstream and downstream processing, formulation and storage. These alterations can take place enzymatically or non-enzymatically and may produce charge or size heterogeneity. Deamidation, proteolytic fragmentation, oxidation, disulfide bond shuffling and glycosylation are the most common modifications that occur during the production of protein therapeutics.4–7 These modifications can reduce the biological activity and may induce immunogenicity in patients. Hence, the regulatory agencies require a comprehensive characterization of the structural integrity, purity and stability of the protein therapeutics.8To date, eight chimeric, humanized and human IgG1 mAbs have been approved in the United States, Europe, as well as other countries, for the treatment of several types of cancers.9–12 One such molecule produced at ImClone has two N-glycosylation sites and at least six to eight isoforms with isoelectric points (pIs) between 7.9–8.9 are present in this product. Although techniques such as ion exchange chromatography (IEX) and capillary isoelectic focusing (IEF) are available for the separation and characterization of charge varients,13,14 we were not successful in separating the individual isoforms with these techniques from the IgG1 product used in this investigation. The peaks from IEX showed the presence of multiple bands on IEF. Hence, an alternative approach was used to isolate each isoform of this IgG1 product, and we demonstrated the involvement of sialic acid and C-terminal lysine as the root causes for lot-to-lot variation observed during the production of this molecule. The method is fast and very effective in separating isoforms with a difference in the pI values < 0.1. 相似文献