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91.
Itoh T Rai T Kuwahara M Ko SB Uchida S Sasaki S Ishibashi K 《Biochemical and biophysical research communications》2005,330(3):832-838
Members of the aquaporin (AQP) water channel family are widely distributed in various tissues and contribute to the water permeability of epithelial and endothelial cells. Currently 11 members of the AQP family (AQP0-10) have been reported in mammals. Here we report the identification of AQP12, which we found by performing a BLAST program search. Northern blot analysis revealed that AQP12 was specifically expressed in the pancreas. Further analysis by in situ hybridization and RT-PCR studies showed that AQP12 was selectively localized in the acinar cells of the pancreas. To analyze the cellular localization and function of AQP12, we expressed AQP12 in Xenopus oocytes and cultured mammalian cells. Immunocytochemistry revealed that AQP12 was not targeted to the plasma membrane. The selective localization of AQP12 in pancreatic acinar cells and possibly in the intracellular organelles suggests a role of AQP12 in digestive enzyme secretion such as maturation and exocytosis of secretory granules. 相似文献
92.
BACKGROUND: Small cell anaplastic hepatoblastoma (HB) is the least common subtype of HB. There are few articles in the literature describing the cytologic characteristics of this rare subtype. CASE: A 5-year-old girl present with a progressively enlarging abdominal mass. Ultrasound examination revealed the mass to be arising within the right lobe of the liver. Fine needle aspiration (FNA) of the mass revealed primitive cells with a high nuclear/cytoplasmic ratio and hyperchromatic, ovoid nuclei in poorly cohesive clusters as well as dispersed singly. These cells closely resembled those of small round cell tumors of childhood. CONCLUSION: The cytologic differential diagnosis of undifferentiated HB must include small round cell tumors of childhood. With knowledge of the typical cytomorphologic appearance of HB in association with clinical and radiologic information, one can offer a reliable preoperative diagnosis on FNA. 相似文献
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95.
Broad-spectrum Blast Resistance Gene Pi-k
h Cloned from Rice Line Tetep Designated as Pi54 总被引:1,自引:0,他引:1
T. R. Sharma A. K. Rai S. K. Gupta N. K. Singh 《Journal of plant biochemistry and biotechnology.》2010,19(1):87-89
Blast disease caused by Magnaporthe oryzae is one of the important biotic stresses of rice. So far more than 85 blast resistance genes have been identified of these more than 14 have already been cloned. A broad spectrum rice blast resistance gene Pi-k h was cloned from the rice line Tetep. The gene was named Pi-k h based on the earlier reports on its genetic analysis in various rice lines. However, with the advances in molecular genetics and genomics of rice, the Pik locus has now been mapped more precisely. Since there are two reports on the mapping of Pi-k h gene from different rice lines, there is some confusion in the naming of this gene. In this report the name of Pi-k h gene cloned from the rice line Tetep has been designated as per the standard guidelines of Committee on Gene Symbolization, Nomenclature and Linkage (CGSNL) and its physical location on rice chromosome 11, which is ~2.5 Mbp away from the Pik locus mapped recently. Hence Pi-k h gene cloned from Tetep is now designated as Pi54. 相似文献
96.
Roz Alfred Tia Gareau Roman Krawetz Derrick Rancourt Michael S. Kallos 《Biotechnology and bioengineering》2010,106(5):829-840
The use of embryonic stem cell (ESC) derived cells has emerged as a potential alternative treatment for a number of degenerative diseases, including musculoskeletal diseases. Conventional ESC culturing methods use fetal bovine serum (FBS) as a major supplemental component of culture media, which is undesirable for clinical applications. These cultures are usually performed in small‐scale static vessels (gelatin‐coated dishes), which limit the number of cells that can be generated. It is essential to develop effective, reproducible protocols for efficient scalable production of ESC‐derived cells. Here we present serum‐free bioreactor protocols for (1) expansion and (2) differentiation of embryonic stem cells to osteoblasts. Cultivation of mESCs in serum‐free media, supplemented with 15% knockout serum replacement (KSR) resulted in a 27.1‐ and 48.6‐fold expansion in static culture and suspension respectively by day 5 of culture. Further induction to osteoblasts with a differentiation cocktail was verified by up‐regulation of osterix and osteocalcin. Mineralization was also enhanced, as indicated by an increase in the calcium deposition by osteogenic cells by day 28. These results will serve as the basis for developing protocols with human ESCs as a new treatment alternative for musculoskeletal diseases. Biotechnol. Bioeng. 2010;106: 829–840. © 2010 Wiley Periodicals, Inc. 相似文献
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P.A. Wadegaonkar K.A. Bhagwat M.K. Rai 《Plant Cell, Tissue and Organ Culture》2006,84(2):100202-100204
Direct rooting from leaf explants of Withania somnifera was achieved on half strength Murashige and Skoog’s medium supplemented with 15 g l−1 sucrose, and different concentrations of growth regulators. Basal medium supplemented with 2.85 μM indoleacetic acid and
9.85 μM indolebutyric acid achieved maximum number of roots with 100% response. The roots were cultured on MS liquid medium
for the establishment of root-organ culture with the same plant growth regulators and incubated on an orbital shaker at 80 rpm
at 25 ± 2 °C. A root biomass of 6.15 ± 0.17 g was obtained after 5 weeks. When 1 g roots were inoculated to 2.5 l bubble column
reactor, 47 g roots were obtained after 6 weeks. The concentration of alkaloids was increased as compared to field grown roots.
The maximum concentration of withanolides (10 mg g−1 dry weight) was obtained in the bioreactor. 相似文献
99.
Zebra fish Dnmt1 and Suv39h1 regulate organ-specific terminal differentiation during development 总被引:1,自引:0,他引:1 下载免费PDF全文
Rai K Nadauld LD Chidester S Manos EJ James SR Karpf AR Cairns BR Jones DA 《Molecular and cellular biology》2006,26(19):7077-7085
DNA methylation and histone methylation are two key epigenetic modifications that help govern heterochromatin dynamics. The roles for these chromatin-modifying activities in directing tissue-specific development remain largely unknown. To address this issue, we examined the roles of DNA methyltransferase 1 (Dnmt1) and the H3K9 histone methyltransferase Suv39h1 in zebra fish development. Knockdown of Dnmt1 in zebra fish embryos caused defects in terminal differentiation of the intestine, exocrine pancreas, and retina. Interestingly, not all tissues required Dnmt1, as differentiation of the liver and endocrine pancreas appeared normal. Proper differentiation depended on Dnmt1 catalytic activity, as Dnmt1 morphants could be rescued by active zebra fish or human DNMT1 but not by catalytically inactive derivatives. Dnmt1 morphants exhibited dramatic reductions of both genomic cytosine methylation and genome-wide H3K9 trimethyl levels, leading us to investigate the overlap of in vivo functions of Dnmt1 and Suv39h1. Embryos lacking Suv39h1 had organ-specific terminal differentiation defects that produced largely phenocopies of Dnmt1 morphants but retained wild-type levels of DNA methylation. Remarkably, suv39h1 overexpression rescued markers of terminal differentiation in Dnmt1 morphants. Our results suggest that Dnmt1 activity helps direct histone methylation by Suv39h1 and that, together, Dnmt1 and Suv39h1 help guide the terminal differentiation of particular tissues. 相似文献
100.
In the present study, we have investigated the effects of NaCl concentrations on the growth and phosphate metabolism of an
Anabaena doliolum strain isolated from a paddy field, in order to determine the possible effects of salinization. Growth rate, chlorophyll
content, and protein content decreased with increasing salt concentration in the growth medium, while carbohydrate concentration
increased. Phosphate content and phosphate uptake rate decreased. There was an increase in total alkaline phosphatase activity,
with an approximately 7-fold increase in extracellular activity compensating for an approximately 3-fold decrease in cell-bound
activity. NaCl effects on protein and chlorophyll concentrations were greater in P-deficient medium, while presence or absence
of P in the medium had little effect on cellular carbohydrate concentrations. It is concluded that growth in high salt likely
leads to reduced phosphate uptake in A. doliolum. 相似文献