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61.
62.
摘要 目的:探讨支气管哮喘(BA)急性发作期患者血清颗粒蛋白前体(PGRN)、分泌型卷曲相关蛋白1(SFRP1)、C-C基序趋化因子配体26(CCL26)与肺功能和气道炎症的相关性。方法:选取2021年1月~2022年6月我院收治的118例BA急性发作期患者作为急性发作期组,根据病情分级将BA急性发作期患者分为轻度亚组55例、中度亚组43例、重度亚组20例,另选取同期77例BA临床控制期患者(临床控制期组)和60例体检健康志愿者(对照组)分别作为对照。采用Pearson相关性分析BA急性发作期患者血清PGRN、SFRP1、CCL26水平与肺功能和气道炎症指标的相关性。结果:对照组、临床控制期组、急性发作期组血清PGRN水平和第1秒用力呼气容积占预计值百分比(FEV1%pred)、峰值呼气流速(PEF)依次降低,SFRP1、CCL26水平和呼出气一氧化氮(FeNO)、外周血嗜酸性粒细胞(EOS)计数依次升高(P<0.05)。轻度亚组、中度亚组、重度亚组血清PGRN水平和FEV1%pred、PEF依次降低,SFRP1、CCL26水平和FeNO、外周血EOS计数依次升高(P<0.05)。Pearson相关性分析显示,BA急性发作期患者血清PGRN水平与FEV1%pred、PEF呈正相关,与FeNO、外周血EOS计数呈负相关(P<0.05),SFRP1、CCL26与FEV1%pred、PEF呈负相关,与FeNO、外周血EOS计数呈正相关(P<0.05)。结论:BA急性发作期患者血清PGRN水平降低,SFRP1、CCL26水平升高,与病情严重程度、肺功能和气道炎症有关,可能成为BA急性发作期患者新的治疗靶点。 相似文献
63.
Abstract: Post-embryonic development is controlled by two types of meristems: apical and lateral. There has been considerable progress recently in understanding the function of root and shoot apical meristems at the molecular level. Knowledge of analogous processes in the lateral, or secondary, meristems, i.e. the vascular cambium or cork cambium, is, however, rudimentary. This is despite the fact that much of the diversity in the plant kingdom is based on the differential functions of these meristems, emphasizing the importance of lateral meristems in the development of different plant forms. The vascular cambium is particularly important for woody plants, but it also plays an important role during the development of various herbaceous species, such as Arabidopsis thaliana. In this review, we focus on the two basic functions of cambial activity: cell proliferation and pattern formation. 相似文献
64.
用离体血管收缩功能实验法分析了大鼠基底动脉(BA)和尾动脉(CA)平滑肌细胞G蛋白的异质性。结果显示,当BA和CA平滑肌被精氨酸血管加压素(AVP)激动后,该两种血管对G蛋白非选择性激活剂GTPγS的收缩反应发生了相反的变化:BA对GTPγS的收缩增强,并且这种收缩增强不受百日咳毒素(PT,Gi和Go抑制剂)的影响。而霍乱毒素(CT,Gs激活剂)则完全抑制这种收缩,呈单相反应。与BA相反,CA对GTPγS的收缩减弱,后者可被PT预温育反转为收缩增强,而且CT对这种收缩的抑制作用短暂,呈双相反应。结果提示,BA和CA平滑肌细胞介导激动剂收缩反应的G蚕白存在异质性。 相似文献
65.
S. A. Smith T. Caceci † H. E-S. Marei ‡ H. A. El-Habback § 《Journal of fish biology》1995,46(2):241-254
In the angelfish ( Pterophyllum scalare scalare ) numerous rodlet cells were found in the large post-orbital blood vessel caudal to the eye and in the surrounding extravascular space. Within the vessel the rodlet cells formed striking regular arrays, along the inner aspect of the wall. The rodlets within the cells were positive to PAS but negative to Sudan Black B, Masson's, and the Fuelgen stain. The capsule around the cells was negative for all these stains. These rodlet cells appeared to be traversing the vessel endothelium, and to be pushing the endothelium aside without damaging it. Some discharged their contents into the vessel, but we never observed the release of intact rodlets. The nuclei of rodlet cells in actual contact with the vessel were at the end of the cell more distant from the endothelial wall. Cell-to-cell adhesion structures or communications junctions between rodlet cells and the endothelium were not evident. A putative rodlet cell precursor in the extravascular space contained large electron-dense granules, and extended pseudopodia that contacted nearby rodlet cells. Based on their morphology, tissue distribution, and their behaviour, we conclude that the rodlet cell is an endogeneous teleost cell type, and possibly represents a form of matured granulocyte. 相似文献
66.
H. Ü. Kolukisaoglu S. Marx C. Wiegmann S. Hanelt H. A. W. Schneider-Poetsch 《Journal of molecular evolution》1995,41(3):329-337
Thirty-two partial phytochrome sequences from algae, mosses, ferns, gymnosperms, and angiosperms (11 of them newly released ones from our laboratory) were analyzed by distance and characterstate approaches (PHYLIP, TREECON, PAUP). In addition, 12 full-length sequences were analyzed. Despite low bootstrap values at individual internal nodes, the inferred trees (neighbor joining, Fitch, maximum parsimony) generally showed similar branching orders consistent with other molecular data. Lower plants formed two distinct groups. One basal group consisted of Selaginella, Equisetum, and mosses; the other consisted of a monophyletic cluster of frond-bearing pteridophytes. Psilotum was a member of the latter group and hence perhaps was not, as sometimes suggested, a close relative of the first vascular plants. The results further suggest that phytochrome gene duplication giving rise to a- and b- and later to c-types may have taken place within seedfern genomes. Distance matrices dated the separation of mono- and dicotyledons back to about 260 million years before the present (Myr b.p.) and the separation of Metasequoia and Picea to a fossil record-compatible value of 230 Myr B.P. The Ephedra sequence clustered with the c- or a-type and Metasequoia and Picea sequences clustered with the b-type lineage. The paleoherb Nymphaea branched off from the c-type lineage prior to the divergence of mono- and dicotyledons on the a- and b-type branches. Sequences of Piper (another paleoherb) created problems in that they branched off from different phytochrome lineages at nodes contradicting distance from the inferred trees' origin.
Correspondence to: H.A.W. Schneider-Poetsch 相似文献
67.
1-acid glycoprotein (AGP) is a serum acute phase glycoprotein which possesses five N-linked complex type heteroglycan side chains which may be present as bi-, tri- and tetraantennary structures. Depending upon the content of biantennary structure on AGP, up to four glycoforms of AGP are present in serum. These glycoforms can be easily estimated in body fluids by means of crossed affinity-immunoelectrophoresis (CAIE) with the lectin, Concanavalin A (Con A). Con A selectively binds biantennary structures; the more biantennary structures on AGP, the stronger the binding. In acute inflammation, a relative increase of AGP glycoforms with biantennary units is observed - a type I glycosylation change. In some chronic inflammatory states there is an relative decrease of AGP glycoforms with biantennary heteroglycans — a type II glycosylation change. Moreover, in certain other states such as pregnancy, estrogen administration or liver damage, type II glycosylation changes are also seen. A detailed analysis of the clinical applications of the assessment of AGP glycoforms in sera of patients with rheumatic diseases, AIDS and various types of cancers is presented. Accumulated data shows that AGP glycoforms may be very useful in the detection of intercurrent infections in the course of rheumatoid arthritis, systemic lupus erythematosus, or myeloblastic leukaemia, and in the detection of secondary infections in human immunodeficiency virus infected individuals. AGP glycoforms are also very useful in differentiation between various forms of trophoblastic disease and are helpful in monitoring the treatment of these patients. Finally, AGP glycoforms provide valuable information for differentiation between primary and secondary liver cancer. 相似文献
68.
Neutrophil influx into tissues occurs in many diverse diseases and can be associated with both beneficial and injurious effects. We hypothesize that the stimulus for certain neutrophilic inflammatory responses can be reduced to a series of competing reactions for iron, with either a labile or reactive coordination site available, between host chelators and chelators not indigenous to that specific living system. The iron focuses the transport of host phagocytic cells through a metal catalyzed generation of oxidant sensitive mediators including cytokines and eicosanoids. Many of these products are chemotactic for neutrophils. We also postulate that the iron increases the activity of the phagocyte associated NADPH oxidoreductase in the neutrophil. The function of this enzyme is likely to be the generation of superoxide in the hostÕs attempt to chemically reduce and dislodge the iron from its chelate complex. After the reoxidation of Fe in an aerobic environment, Fe will be coordinated by host lactoferrin released by the neutrophil. When complexed by this glycoprotein, the metal does not readily undergo oxidation/reduction and is safely transported to the macrophages of the reticuloendothelial system where it is stored in ferritin. Finally, we propose that the neutrophil will attempt to destroy the chelator not indigenous to the host by releasing granular contents other than lactoferrin. Inability to eliminate the chelator allows this sequence to repeat itself, which can lead to tissue injury. Such persistence of a metal chelate in the host may be associated with biomineralization, fibrosis, and cancer. 相似文献
69.
70.
Shigeki Nagao Yoshihiro Kawabata Takashige Nishikawa Haruhiko Takada 《Microbiology and immunology》1995,39(12):1011-1014
Guinea pigs immunized with Freund's complete adjuvant received challenge injection of the purified protein derivative of Mycobacterium tuberculosis in the flanks and the corneas to prepare delayed-type hypersensitivity (DTH) reactions. The animals were injected subcutaneously with lipopolysaccharide (LPS) or a synthetic lipid A (LA-15-PP). At the skin site primed with DTH reaction, increased swelling and hemorrhagic reaction followed by a definite necrotic reaction occurred. Severe corneal reactions were also observed in the animals. These findings indicate that bacterial endotoxin modulates DTH reactions and induces severe inflammatory reactions. 相似文献