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301.
Exosomes secreted from mutant‐HIF‐1α‐modified bone‐marrow‐derived mesenchymal stem cells attenuate early steroid‐induced avascular necrosis of femoral head in rabbit 下载免费PDF全文
302.
Shui Qing Ye MD PhD David Usher Donna Virgil Li Qin Zhang Scott E. Yochim Rana Gupta 《Journal of biomedical science》1999,6(1):18-21
The mutation of serine128 to arginine in the CD 62E gene is a risk factor for coronary artery disease (CAD). We designed a new method to detect this mutation based on the observation that it is due to a transversion of nucleotide A561 to C, which abolishes aPstI recognition site. Two alleles, A and C, are easily typed when genomic DNA is amplified by PCR, digested withPstI, and separated on agarose gels. Among 153 people who underwent an elective, diagnostic arteriography in Johns Hopkins Hospital, we found that the C allele accounts for 19.5% in angiographically documented CAD patients (n=82). It is significantly higher than the 10.6% frequency observed in normal controls (n=71, p<0.05). It indicates that the C allele is associated with early-onset CAD. This new method should facilitate the screening of this mutant allele in large populations and contribute to the understanding of the molecular mechanism underlying the association of this mutation with CAD. 相似文献
303.
Progestins in the menopause 总被引:2,自引:0,他引:2
Rgine Sitruk-Ware MD 《The Journal of steroid biochemistry and molecular biology》1999,69(1-6):185-193
While the benefits of progestin use in hormone replacement therapy (HRT) are well recognised as far as endometrial protection is concerned, their risks and drawbacks have generated controversial articles. The data related to the progestin effect on breast tissue has been interpreted differently from country to country. However it has been admitted that, according to the type of progestin used, the dose and duration of its application, a predominant antiproliferative effect is observed in the human breast cells. As far as breast cancer risk is concerned, most epidemiological studies do not suggest any difference between the estrogens given alone or combined to progestins in HRT. When the cardiovascular risk factors are considered, some molecules with a higher androgenic potency than others, attenuate the beneficial effects of estrogens on the lipid profile and the vasomotion as well. On the other hand, other progestins devoid of androgenic properties do not exert these deleterious effects. The epidemiological data does not suggest any negative effect of the progestins administered together with estrogens on cardiovascular morbidity or mortality.
However, recent results suggest that in women with established coronary heart disease (CHD), HRT may not protect against further heart attacks, when the progestin selected possesses androgenic properties.
Complying with the classic contra indications of HRT and selecting molecules devoid of estrogenic, androgenic, or glucocorticoid effect should allow a larger use of the progestins without any major drawback. 相似文献
304.
Raska M Beláková J Wudattu NK Kafková L Růzicková K Sebestová M Kolár Z Weigl E 《Folia microbiologica》2005,50(1):77-82
Preventive vaccination by a hsp90-expressing DNA vaccine and recombinant hsp90 protein vaccine, both derived from the Candida albicans hsp90 using BALB-c mouse model of systemic candidiasis, was performed. Hsp90 mRNA was cloned from a clinical isolate of C. albicans, converted to cDNA and cloned into vaccination plasmid pVAX1. Two methods of DNA application were tested: intramuscular (i.m.) and intradermal (i.d.) injection. Recombinant protein was applied by i.d. injection with Freund's adjuvant; the control groups received PBS or Freund's adjuvant only. Mice were vaccinated and after 19 d re-vaccinated. After 3 weeks, the mice were challenged with the live C. albicans in a dose of 5 x 10(6) CFU per mouse. After the challenge, the mice vaccinated i.d. with DNA vaccine survived for 39 and 64% longer compared to those receiving Freund's adjuvant and/or PBS, respectively. The i.m. application of the DNA vaccine did not provide any significant protectivity. The serum level of anti-candida-hsp90 serum IgG antibodies correlated with the survival rate in both i.d. protein and DNA vaccination approaches. We stressed the importance of specific humoral immunity in the mouse model of systemic candidiasis. 相似文献
305.
Yitian Zheng MD Binhao Shi MD Mengqing Ma MD Xiaoqin Wu PhD Xianhe Lin MD PhD 《Journal of cellular physiology》2019,234(5):5488-5495
Class III histone deacetylases (HDACs) belong to the proteasome family, comprising seven family members identified in mammalian cells, identified Sirt1–Sirt7. As an important member of HDACs, Sirt3 is hotly debated for its multiple functions. It was reported that Sirt3 got involved in the alleviation of multiple diseases, including myocardial infarction, neuron ischemia, hypertrophy, and diabetic myopathy. Through regulating many cellular mechanisms, such as apoptosis, autophagy, and clearance of reactive oxygen species (ROS), Sirt3 played an important role in the alleviation of myocardial ischemia–reperfusion injury. Nowadays Sirt3-induced autophagy was indicated to be involved in the process of the development of myocardial ischemia–reperfusion injury. Sirt3 could both activate and inhibit autophagy process by activating different downstream signal pathways, such as Sirt3–AMP-activated protein kinase pathway, Sirt3–Foxo3a pathway, and Sirt3–superoxide dismutase–mitochondrial ROS pathway. Whereas the Sirt3-induced autophagy in different phases of myocardial ischemia–reperfusion has not been systematically illustrated. In this review, we summarized the regulated mechanisms found in these years and listed the updated research about the relationship between Sirt3 and autophagy which are both positive and negative during myocardial ischemia–reperfusion phase. We anticipated that we may controlled the activation of autophagy by regulating the concentration of Sirt3 in myocyte. By maintaining a proper expression of autophagy in different phases of myocardial ischemia–reperfusion, we could reduce the morbidity of patients with myocardial infarction apparently in the future. 相似文献
306.
A case of mycetoma, with abscess-like lesions which appeared on the right forearm of a 43-year-old male, is briefly reported. A few whitish granules were detected in the oily-like discharge, the same as in the histologic examination. No bone involvement was discovered in X-ray examination. Actinomadura was identified in the culture. A daily dose of 4 g bactrin brought significant improvement to the patients continuing the treatment. 相似文献
307.
Hao Zhang MD Yang Gao MD Yiming Wang MD Yi Yan MD Zhijian Yang MD PHD Dengshun Miao PHD Dingguo Zhang MD PHD 《Journal of cellular biochemistry》2019,120(9):14745-14755
It is known that parathyroid hormone-related peptide (PTHrP) contains a nuclear localization sequence (NLS, 87-107), which, together with its C-terminus (107-139), has been shown to positively regulate vascular smooth muscle cell (VSMCs) proliferation and vascular neointima formation, and inhibit cellular apoptosis. The role of PTHrP in ischemic cardiac diseases remains unclear. In this study, we attempted to determine whether PTHrP 87 to 139 can play a role in promoting cardiac function via enhancing angiogenesis after myocardial infarction (MI) occurred. MI was reproduced in C57BL/6 mice using a coronary artery ligation method. In total, three groups (n = 11 per group) of animals were used, and they were received either PTHrP 87 to 139 (80 µg/kg, treatment group) or saline (MI and Sham group) subcutaneously once a day for 4 weeks after MI. To measure cardiac function, an echocardiography was generated and cardiac tissue was harvested for immunohistological studies 4 weeks after operation. Our results show that, after MI, the cardiac function of the experimental mice was significantly impaired. PTHrP 87 to 139 treatment attenuated cardiac dysfunction in MI mice. Besides, as indicated by decreased heart weight/body weight and lung weight/body weight ratio, PTHrP 87 to 139 attenuated pulmonary congestion and cardiac hypertrophy. Masson staining revealed that PTHrP 87 to 139 attenuated myocardial fibrosis after MI. Also, terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling staining and the expression of cleaved caspase 3 suggested that MI-induced myocytes apotosis was inhibited by PTHrP 87 to 139. In addition to the significantly increased capillary density, PTHrP 87 to 139 treatment also induced p-Akt and several angiogenic factors. In conclusion, PTHrP 87 to 139 treatment preserved cardiac function after MI, and stimulated angiogenesis via upregulating vascular endothelial growth factor and basic fibroblast growth factor (bFGF) in infarct border zone of ischemic myocardium,. These results suggest that PTHrP 87 to 139 is of therapeutic potential for MI. 相似文献
308.
309.
ADRIAN B. LIGGINS PhD PEng W. ROBERT HARDIE MD CAND-ING FRANK WEBER EUR ING J. BRYAN FINLAY PhD PEng 《Computer methods in biomechanics and biomedical engineering》2013,16(4):333-342
Rationale and Objectives. To reduce tibio-femoral misalignment, the polyethylene bearing-component of a new knee prosthesis was allowed limited motion on the underlying metallic component. The object of the work presented here was to develop a suitable radiographic technique for quantifying the in-vivo position of the bearing. By collecting these data at discrete flexion angles, the functional operation of the prosthesis could be determined Methods. The known geometries between landmarks on the two components were used to produce algorithms for reconstructing their spatial positions from a single radiograph. A custom-designed computer program utilized these algorithms to determine the relative translation and rotation of the polyethylene component Results. This technique produced typical errors of 0.54 mm translation and 0.56° rotation between the polyethylene component and the underlying metallic component Conclusions. A practical method has been developed for assessing mobile-bearing motion, in vivo. This method can be applied to other prosthetic devices, or combinations of components, once the requirement for identifiable landmarks has been addressedClinical Relevance. Skeletal and soft-tissue changes in the pathological knee may produce abnormal rotations and translations in the transverse tibial plane. This technique is intended both to validate the design philosophy of a mobile-bearing prosthesis and to provide additional data on any pathological motions, which will have implications for future prosthetic designs. 相似文献