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101.
Summary Our study of fifty two hay fever patients included twenty six solely allergic to grass pollen and twenty six exhibiting allergy to various pollen species, such as hazel, birch, oak, poplar, andArtemisia. Their total and specific IgE response was evalutated by the immunoenzymatic method, while clinical reactivity was assessed by recording nasal and bronchial symptom scores between mid-March and mid-July. Simultaneously pollen counts were made. Polysensitized patients showed significantly higher levels of both total and specific IgE, which testifies to the enhanced quantitative and qualitative IgE. Multisensitized patients reacted earlier than patients sensitized to grass pollen only, which confirms that non-grass plants flowering only in the spring cause the priming effect on the nasal and bronchial mucosa. The early symptoms may be attributable to tree pollen sensitivity or may refletct higher grass pollen IgE levels in the polysensitized group. Characteristically, nasal symptoms preceded bronchial symptoms of several weeks.On comparing nasal washing from the polysensitized patients to washing from patients with grass pollen, we found much cytological material with the predominance of eosinophils.  相似文献   
102.
De novo biosynthesis of pyridine nucleotide coenzymes in Escherichia coli is initiated by an enzyme complex (quinolinate synthetase) containing protein B which converts l-aspartate into iminoaspartate protein A, which then generates quinolinate on the pathway to the coenzymes. This complex has been shown to be poisoned by hyperbaric oxygen. 7,8 We performed assays made dependent on both proteins B and A versus only protein A, using cell-free extracts of hyperbaric-oxygen poisoned and aerobically grown cells. The specific activities were produced by a similar amounts of 68% and 60%, respectively, when measured in assays made dependent on enzymes B and A versus only protein A that was derived from oxygen-poisoned extract. Thus, protein A is the oxygen-sensitive component.  相似文献   
103.
Bacteria deploy weapons to kill their neighbours during competition for resources and to aid survival within microbiomes. Colicins were the first such antibacterial system identified, yet how these bacteriocins cross the outer membrane (OM) of Escherichia coli is unknown. Here, by solving the structures of translocation intermediates via cryo‐EM and by imaging toxin import, we uncover the mechanism by which the Tol‐dependent nuclease colicin E9 (ColE9) crosses the bacterial OM. We show that threading of ColE9’s disordered N‐terminal domain through two pores of the trimeric porin OmpF causes the colicin to disengage from its primary receptor, BtuB, and reorganises the translocon either side of the membrane. Subsequent import of ColE9 through the lumen of a single OmpF subunit is driven by the proton‐motive force, which is delivered by the TolQ‐TolR‐TolA‐TolB assembly. Our study answers longstanding questions, such as why OmpF is a better translocator than OmpC, and reconciles the mechanisms by which both Tol‐ and Ton‐dependent bacteriocins cross the bacterial outer membrane.  相似文献   
104.
Characterization of the Pregnancy-Associated Glycoproteins (PAG) is important for studies of reproduction of various eutherian domestic, wild and endangered mammals. Distinct chorionic PAG genes are expressed in embryo-origin cells: pre-placental trophoblast (TR) and in placental trophectoderm (TRD) of various entherians. This study demonstrates in vitro production of the PAG proteins during long-term cultures of various chorionic explants: porcine TR or TRD, cotyledonary (CT) of European bison (Eb), and CT or intercotyledonary (intCT)-TRD of the cattle. Chorionic proteins isolated from media were analyzed by homologous or heterologous Western immunoblotting with anti-PAG sera, raised against cellular bovine or secretory porcine antigens. Used anti-PAG sera identified diverse molecular forms of released PAG proteins: 43-69 kDa for EbPAG proteins, 40-85 kDa for bovine PAG (bPAG), and 43-73 kDa for porcine PAG (pPAG). Immunoblotting revealed also that both CT and intCT-TRD explants secreted equivalent amounts of bPAG proteins. This useful system of in vitro protein production can provide native chorionic PAG proteins with placental unique carbohydrate chains. The PAG proteins are required as standard markers for diagnostic tests of pregnancy in domestic and wild mammals, in which seasonal reproductive processes are relatively difficult to control.  相似文献   
105.
TGF beta signalling and its role in tumour pathogenesis   总被引:10,自引:0,他引:10  
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106.
107.
Quercetin suppresses heat shock-induced nuclear translocation of Hsp72   总被引:1,自引:0,他引:1  
The effect of quercetin and heat shock on the Hsp72 level and distribution in HeLa cells was studied by Western blotting, indirect immunofluorescence and immunogold electron microscopy. In control cells and after quercetin treatment, Hsp72 was located both in the cytoplasm and in the nucleus in comparable amounts. After hyperthermia, the level of nuclear Hsp72 raised dramatically. Expression of Hsp72 in cytoplasm was also higher but not to such extent as that observed in the nucleus. Preincubation of heated cells with quercetin inhibited strong Hsp72 expression observed after hyperthermia and changed the intracellular Hsp72 distribution. The cytoplasmic level of protein exceeded the nuclear one, especially around the nucleus, where the coat of Hsp72 was noticed. Observations indicating that quercetin was present around and in the nuclear envelope suggested an involvement of this drug in the inhibition of nuclear translocation. Our results indicate that pro-apoptotic activity of quercetin may be correlated not only with the inhibition of Hsp72 expression but also with suppression of its migration to the nucleus.  相似文献   
108.
The aim of this investigation was to characterize the phospholipid composition of normal human blood mononuclear cells using 31P NMR spectroscopy. Mononuclear cells of peripheral blood were obtained from 10 volunteers. Phospholipid extracts were prepared from 60x10(6) cells according to modified Folch's method. An AMX 300 Bruker spectrometer 7.05 T was used. The 31P spectrum of phospholipid extracts from normal human PBMC consisted of 9 peaks, with one each for phosphatidylcholine (PC), plasmalogen of phosphatidylcholine (CPLAS), lysophosphatidylcholine (LPC), sphingomyelin (SM), phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylserine (PS) and cardiolipin (CL), and another one due to the external reference substance, methylenediphosphonic acid (MDPA). The concentrations of these phospholipids (PL), based on the integral intensities, were as follows: 0.398 +/- 0.078 mmole/l for PC; 0.033 +/- 0.019 mmole/l for CPLAS; 0.155 +/- 0.043 mmole/l for SM; 0.266 +/- 0.104 mmole/l for PI+PE; 0.101 +/- 0.040 mmole/l for PS, and 0.026 +/- 0.033 mmole/l for CL. The results of this study confirmed that 31P MRS is a convenient tool for measuring the phospholipid concentrations of biological samples.  相似文献   
109.
Fibrosis of oesophagus, lungs, heart, and kidney in the course of systemic sclerosis (SSc) may lead to dysfunction of the above organs or even patients death. Recent studies point out the role of angiogenesis and fibrosis disturbances in the pathogenesis of SSc. Heart fibrosis is one of the most important prognostic factors in SSc patients. So, the aim of our study was to examine cardiovascular dysfunction in SSc patients and its correlation with serum levels of vascular endothelial growth factor (VEGF), endostatin, and tissue inhibitor of metalloproteinase 2 (TIMP2). The study group comprised 34 patients (19 with limited scleroderma (lSSc) and 15 with diffuse scleroderma (dSSc)). The control group consisted of 20 healthy persons, age and sex matched. Internal organ involvement was assessed on the basis of specialist procedures. Serum VEGF, endostatin, and TIMP2 levels were evaluated by ELISA. We found cardiovascular changes in 15 patients with SSc (8 with lSSc and 7 with dSSc). The observed symptoms were of different characters and also coexisted with each other. Higher endostatin serum levels in all systemic sclerosis patients in comparison to the control group were demonstrated (P < .05). Also higher serum levels of endostatin and TIMP2 were observed in patients with cardiovascular changes in comparison to the patients without such changes (P < .05). The obtained results support the notion that angiogenesis and fibrosis disturbances may play an important role in SSc. Evaluation of endostatin and TIMP2 serum levels seems to be one of the noninvasive, helpful examinations of heart involvement in the course of systemic sclerosis.  相似文献   
110.
Acetylcholinesterase (AChE - EC. 3.1.1.7) plays an essential role in acetylcholine-mediated neurotransmission. Unfortunately, an AChE-peptide exhibits pathophysiological activity via an apoptotic pathway that could play an important role in neuronal development and neurodegeneration. It was found that a peptide derived from AChE may induce neuronal death and acetylcholinesterase may induce neurological changes in the development of Alzheimer's disease. It was also stated that complex of AChE with beta-amyloid is much more toxic than amyloid and causes stronger neurological changes. AChE promotes the generation of amyloid by accelerating the expression of peptide precursor (beta-APP) in glial cells. The essential role is also played by AChE in induction of hematological disease. It is well known that phospho-organic compounds cause inhibition of AChE precursors what is related to decrease of hemoglobin concentration, number of erythrocytes and hematocrit level. The article is an attempt to explain the role of acetylcholinesterase in neuronal apoptosis, Alzheimer's disease and Myasthenia gravis as well as in leukemia.  相似文献   
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