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41.
H. Yamada Y. Saito M. Mukoyama K. Nakao H. Yasue T. Ban H. Imura Y. Sano 《Histochemistry and cell biology》1988,89(5):411-413
Summary To date, there have been few immunohistochemical investigations of atrial natriuretic polypeptide (ANP) in human cardiac tissue, especially the ventricles. In this study, myocardial tissue was obtained from two sources: the bilateral atria and ventricles at autopsy; and biopsy tissues from the right auricle and left ventricle of a patient with myocardial infarction undergoing surgery. These tissues were examined by the avidin-biotin immunoperoxidase technique using three kinds of primary ANP-antibodies. ANP-immunoreactivity was observed in the perinuclear region of myocytes of all tissues examined. The intensity of the reaction was stronger in atrial tissue, weaker in ventricular tissue. In the later tissue, the positive-staining myocytes were not part of the pulse-conducting system. Although the tissues we studied were not obtained from normal hearts, our data demonstrates that ANP-reactivity can be detected in ventricular myocytes outside the pulse-conducting system. 相似文献
42.
The heterogeneity and differential expression of protein kinase C in nervous tissues 总被引:1,自引:0,他引:1
43.
T Morii M Shimomura I Saito H Ide A Murakami K Makino 《Nucleic acids symposium series》1992,(27):177-178
A chiral template with C2 symmetry has been used for modeling a dimeric interface of DNA binding protein. An oligopeptide derived from the basic region of MyoD, a recently described "helix-loop-helix" class of DNA binding protein, has been tethered to the template. Among the four models which differ in chirality and polarity with respect to the arrangement of two subunits, only one dimer model with right-handed and C-terminus to C-terminus arrangement of the peptide subunits binds DNA containing native MyoD binding sequence. 相似文献
44.
45.
M Saito 《Human cell》1992,5(1):54-69
A recent trend in hematological research fields has been to isolate and characterize hematopoietic stem cells/progenitors and their growth factors (hemopoietins) to gain a much better understanding of the nature of the stem cell and the mechanisms regulating its development. It is generally accepted that all the various types of blood cells develop from a single progenitor called a hematopoietic stem cell. Quantitative studies of the function of hemopoietic stem cells began two decades ago with the development of a spleen colony assay, and then, clonal cell culture techniques for committed progenitors were developed with several models for hematopoietic differentiation being proposed. Within the last few years, some hormones have been discovered that are known as hematopoietic growth hormones or hemopoietins, each of which is of protein nature and causes specific classes of blood cells to be made and primed. These hormones also enhance the function of the mature cells, the genes of which have recently been cloned. On the other hand, long-term bone marrow culture has recently permitted detailed investigations of the relationship between hematopoietic cells and the microenvironment in which they are found, e.g. stromal cells, in vitro, relating to the regulation of cell proliferation and differentiation. Further, in hematological fields, other bioactive factors including differentiation-inducing compounds, e. g. bioactive glycosphingolipids, and leukocyte-endothelial cell recognition molecules (adhesion receptors) have been discovered, the molecular mechanism(s) of which have yet to be elucidated. This communication focuses on recent advances in research on soluble hemopoietins and other bioactive factors relating to differentiation-induction and to cell-to-cell recognition. 相似文献
46.
Acute pulmonary alveolar hypoxia increases lung and plasma endothelin-1 levels in conscious rats. 总被引:13,自引:0,他引:13
G Shirakami K Nakao Y Saito T Magaribuchi M Jougasaki M Mukoyama H Arai K Hosoda S Suga Y Ogawa 《Life sciences》1991,48(10):969-976
To investigate the effect of pulmonary alveolar hypoxia on the synthesis and release of endothelin (ET)-1, ET-1-like immunoreactivity (-LI) levels of the lung and plasma were measured in conscious unrestrained rats under hypoxic conditions. Sixty-min exposure to alveolar hypoxia (10% O2 or 5% O2) increased the ET-1-LI level in the lung. The plasma ET-1-LI level in hypoxic rats also increased significantly. The increase of plasma and lung ET-1-LI levels were parallel to the severity of hypoxia. These results demonstrates that acute pulmonary alveolar hypoxia increases lung and plasma ET-1-LI levels in conscious unrestrained rats, suggesting a possible physiological or pathophysiological significance of ET in alveolar hypoxia. 相似文献
47.
Dipeptidyl peptidase IV (DAP IV) was purified from Streptococcus salivarius HHT by anion-exchange chromatography, gel filtration and affinity chromatography after lysis of cell walls with N-acetylmuramidase. DAP IV was purified 114-fold with a yield of 16.6% from total activity of the crude extract. The purified enzyme was shown to be homogeneous by disc gel electrophoresis. The molecular weight of the enzyme was estimated to be about 109,000 by gel filtration and 47,000 by sodium dodecylsulphate SDS-polyacrylamide gel electrophoresis, suggesting that the native enzyme is a dimeric form. The optimum pH for the reaction was 8.7 in Gly-NaOH buffer, and the isoelectric point of the enzyme was pH 4.2. The enzyme hydrolysed specifically N-terminal X-Pro from X-Pro-p-nitroanilides. The enzyme activity was hardly affected by various cations, sulphydryl-blocking reagents and metal chelators. The enzyme activity was markedly inhibited by 1 mM diisopropylfluoride, and the desialysed enzyme was attacked by proteinases. 相似文献
48.
M Shibata T Seki T Yoshizu H Saito T Tajima 《Plastic and reconstructive surgery》1991,88(1):102-9; discussion 110
Free nonvascularized toenail grafts have been used to reconstruct congenital or traumatic nail defects of the thumb or finger. Unfortunately, these transfers often result in deformity or atrophy. To avoid these undesirable results, microsurgical free vascularized toenail transfer was performed in 10 patients, 3 for congenital nail absence and 7 for traumatic nail defects. Patient age averaged 17 years (range 2 to 32 years). In contrast with previous reports, the whole big or second toenail complex without pulp was used in reconstruction. All 10 nails were successfully transferred with complete survival. No digits required reexploration. There were no donor- or recipient-site problems. Follow-up averaged 3 years, with a range of 14 months to 5 years and 4 months. Appropriate nail growth occurred in the congenital patients. No atrophy of the nail complex was found as long as sufficient bony support was present (9 of 10 cases). Whole free vascularized toenail transfers for reconstruction of congenital and traumatic nailbed defects achieve excellent aesthetic results while maintaining normal hand function. 相似文献
49.
Hidenori Shinkawa Masanori Sugiyama Yuji Hatada Takeshi Ohuchi Masao Udagawa Osamu Nimi 《Biotechnology letters》1991,13(8):537-542
Summary The bald mutants from streptomycin (SM)-producingStreptomyces griseus 2247 obtained by incubation at high temperature (36° C), designated as HT strains, lost resistance to their own antibiotic and scarcely produced the antibiotic. Although SM susceptibility in the mutant was due to loss of SM 6-phosphotransferase activity produced in the cell, the gene coding for the enzyme cloned from an HT strain was surely expressed inS. lividans 1326 as a host. Northern blot analysis showed that the corresponding RNA is not detected in the mutant, indicating that though the gene encoding SM 6-phosphotransferase, at least, the structural gene is not deleted in the cell, the expression is silent. 相似文献
50.