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31.
Aspiration biopsy smear pattern as a predictor of biologic behavior in adenocarcinoma of the breast.
Fine needle aspiration cytology (FNAC) is increasingly used for the initial diagnosis of breast carcinoma, yet few studies have investigated the prognostic importance of cytologic features seen in breast FNAC. We studied the relationship between prognosis and smear morphology in 26 patients with breast carcinoma for whom information from long-term follow-up was available. Specifically, we attempted to correlate nuclear grade and smear pattern with hormonal receptor status, lymph node status, breast recurrence and distant metastasis. In an additional five patients (on whom insufficient follow-up information was available), smear pattern and nuclear grade were correlated with hormonal status. Smears were classified into three patterns: typical (sheets and clusters), individual cell predominant and cluster predominant. The individual cell predominant pattern was associated with an increased incidence of distant metastasis when compared with the other two smear patterns (P less than .05). No statistically significant association was observed between smear pattern and the other factors studied. Nuclear grade 2 (of 3) was also associated with an increased incidence of distant metastasis. However, most grade 2 tumors (10/12) were of the individual cell predominant pattern. Smear pattern classification, along with DNA ploidy analysis and hormone receptor analysis of FNAC-derived material, may yield valuable prognostic information. 相似文献
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Douwe M. Veltman Michael G. Lemieux David A. Knecht Robert H. Insall 《The Journal of cell biology》2014,204(4):497-505
In eukaryotic chemotaxis, the mechanisms connecting external signals to the motile apparatus remain unclear. The role of the lipid phosphatidylinositol 3,4,5-trisphosphate (PIP3) has been particularly controversial. PIP3 has many cellular roles, notably in growth control and macropinocytosis as well as cell motility. Here we show that PIP3 is not only unnecessary for Dictyostelium discoideum to migrate toward folate, but actively inhibits chemotaxis. We find that macropinosomes, but not pseudopods, in growing cells are dependent on PIP3. PIP3 patches in these cells show no directional bias, and overall only PIP3-free pseudopods orient up-gradient. The pseudopod driver suppressor of cAR mutations (SCAR)/WASP and verprolin homologue (WAVE) is not recruited to the center of PIP3 patches, just the edges, where it causes macropinosome formation. Wild-type cells, unlike the widely used axenic mutants, show little macropinocytosis and few large PIP3 patches, but migrate more efficiently toward folate. Tellingly, folate chemotaxis in axenic cells is rescued by knocking out phosphatidylinositide 3-kinases (PI 3-kinases). Thus PIP3 promotes macropinocytosis and interferes with pseudopod orientation during chemotaxis of growing cells. 相似文献
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Aisada Uchugonova Wenluo Cao Robert M Hoffman Karsten Koenig 《Cell cycle (Georgetown, Tex.)》2015,14(21):3430-3433
Hair-follicle-associated pluripotent (HAP) stem cells can differentiate into many cell types, including neurons and heart muscle cells, and have been shown to repair peripheral nerves and the spinal cord in mice. HAP stem cells can be obtained from each individual patient for regenerative medicine which overcomes problems with immune rejection. Previously, we have demonstrated that genetically-encoded protein markers such as GFP in transgenic mice can be used to visualize HAP stem cells in vivo by multiphoton tomography. Detection and visualization of stem cells in vivo without exogenous labels such as GFP would be important for human application. In the present report, we demonstrate label-free visualization of hair follicle stem cells in mouse whiskers by multiphoton tomography due to the intrinsic fluorophores such as NAD(P)H/flavins. We compared multiphoton tomography of GFP-labeled HAP stem cells and unlabeled stem cells in isolated mouse whiskers. We show that observation of HAP stem cells by label-free multiphoton tomography is comparable to detection using GFP-labeled stem cells. The results described here have important implications for detection and isolation of human HAP stem cells for regenerative medicine. 相似文献
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A number of Arabidopsis thaliana mutants with abnormal rootmorphology have been isolated from a population of Agrobacterium-mediated seed transformants. Five of these mutants identifiedby their abnormal root morphology have been genetically andmorphologically characterised. Two mutants, 5905 and 1767 havedefective cellular elongation, mutant 7203 lacks an endodermalcell layer and mutants 4792 and 7133 exhibit abnormal radialcellular expansion. It is apparent from detailed analysis thatabnormal root morphology is accompanied by abnormal hypocotylphenotype. Genetic analysis has revealed that only one of thesemutants is tagged with a T-DNA insert.Copyright 1994, 1999 AcademicPress Arabidopsis thaliana, root, development, T-DNA insertion mutagenesis, endodermis, elongation 相似文献
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