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121.
Marine Tubificidae (Oligochaeta) of Antarctica, with descriptions of three new species of Phallodrilinae 总被引:1,自引:0,他引:1
CHRISTER ERSÉUS 《Zoologica scripta》1994,23(3):217-224
Five species of Tubificidae are recorded from Antarctic waters: Torodrilus lowryi Cook, 1970, Torodrilus sp. (subfamily Rhyacodrilinae), Marionidrilus antarcticus sp. n., M. weddellensis sp. n., and Thalassodrilus bicki sp. n. (subfamily Phallodrilinae); only T. lowryi was known from Antarctica before. The status of the two Southern Hemisphere genera Torodrilus Cook, 1970, and Marionidrilus Erséus, 1992, are discussed; although the taxonomic position of the two new species of Marionidrilus is somewhat uncertain. Thalassodrilus bicki , however, appears closely related to Northern Hemisphere taxa. 相似文献
122.
CHRISTER ERSÉUS 《Zoologica scripta》1990,19(3):243-303
Fifty-nine species of Tubifieidae are recorded from Belize on the Caribbean side of Central America. Twenty-five are new to science: Ainudrilus geminus sp.n., Heronidrilus gravidus sp.n., Heterodrilus flexuosus sp.n., H. ranus sp.n., H. modestus sp.n., Coralliodrilus rugosus sp.n., C. randyi sp.n., Phallodrilus compactus sp. n., P. singularis sp.n., P. vicinus sp.n., P. nasutus sp.n., P. bipartitus sp.n., Inanidrilus reginae sp.n., Olavius finitimus sp.n., O. vacuus sp.n., O. (Olavius) pravus sp.n., Bathydrilus vetustus sp.n., B. egenus sp.n., Thalassodrilides bruneti sp.n., Limnodriloides anxius sp.n., L. major sp.n., L. sacculus sp.n., L. adversus sp.n., Smithsonidrilus appositus sp.n., S. involutus sp.n. Phylogenetic analyses indicate that Heterodrilus Pierantoni, 1902, Thalassodrilides Brinkhurst & Baker, 1979, and Marcusaedrilus Righi & Kanner, 1979, are paraphyletic taxa as previously defined. They are therefore revised to include also apomorphic species earlier attributed to separate genera; in so doing, Marcusaedrilus becomes a junior synonym of Smithsonidrilus Brinkhurst, 1966. Smithsonidrilus pauper sp.n. (Peru), and S. multiglandularis sp.n. (Florida and Puerto Rico) are also described, and Limnodriloides claviger Erséus, 1982 is regarded as a synonym of L. pierantonii (Hrabě, 1971). 相似文献
123.
Increased expression of the maize immunoglobulin binding protein homolog b-70 in three zein regulatory mutants. 总被引:4,自引:8,他引:4 下载免费PDF全文
Plants carrying floury-2, Defective endosperm-B30, or Mucronate mutations overproduce b-70, a maize homolog of the mammalian immunoglobulin binding protein. During endosperm development in these mutants, levels of both b-70 protein and RNA increase dramatically between 14 days and 20 days after pollination. At later stages, b-70 RNA levels decline while protein levels remain high. The increase in b-70 RNA levels is endosperm specific and dependent on gene dosage in the floury-2 mutant. In all three mutants, the increases in b-70 RNA and protein levels are inversely proportional to changes in zein synthesis. Although b-70 polypeptides can be extracted from purified protein bodies, they carry a carboxy-terminal endoplasmic reticulum retention signal, HDEL. We propose that induction of b-70 in these mutants is a cellular response to abnormally folded or improperly assembled storage proteins and probably reflects its role as a polypeptide chain binding protein. 相似文献
124.
Eleven polymorphic microsatellite marker loci were developed from a Leisler’s bat (Nyctalus leisleri) genomic enriched library. Assessment of the usefulness of these markers for population genetics studies of Leisler’s bats
was carried out by screening 100 specimens sampled from eight locations in Ireland and two in Northeastern France. Both moderately
and highly polymorphic marker loci were identified. Five to 28 alleles were found to be segregating per locus with observed
heterozygosities values ranging from 28.4 to 94%. Initial evaluation indicates that these microsatellites will be useful for
genetic based studies aiming, for instance, at parentage and population structure of Leisler’s bats. 相似文献
125.
Gurnit Kaur Elaine M. Leslie Holly Tillman William M. Lee Diane P. Swanlund Constantine J. Karvellas US Acute Liver Failure Study Group 《PloS one》2015,10(9)
Background/Aim
Acetaminophen (APAP) hepatotoxicity is related to the formation of N-acetyl-p-benzoquinone imine (NAPQI), which is detoxified through conjugation with reduced glutathione (GSH). Ophthalmic acid (OA) is an analogue of GSH in which cysteine is replaced with 2-aminobutyrate. Metabolomics studies of mice with APAP-induced acute liver failure (APAP-ALF) identified OA as a marker of oxidative stress and hepatic GSH consumption. The aim of the current study was to determine whether OA is detectable in APAP-ALF human patients either early (day 2) or late (day 4) and whether OA levels were associated with in-hospital survival in the absence of liver transplant.Methods
Serum samples from 130 APAP-ALF patients (82 survivors, 48 non-survivors) were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and correlated with clinical data from the United States Acute Liver Failure Study Group (US ALFSG) Registry (2004–2011).Results
Survivors had significantly lower admission bilirubin (4.2 vs. 5.7 mg/dl) and lactate levels (3.3 vs. 6.5 μmol/l, p<0.05 for all). During the first 7 days of the study, survivors were less likely to require mechanical ventilation (55% vs. 88%), vasopressor support (9.8% vs. 67%) or renal replacement therapy (26% vs. 63%, p< 0.001 for all). Non-survivors were more likely to have detectable OA levels early (31% vs. 15%, p = 0.034) and late (27% vs. 11%, p = 0.02). However there were no significant differences in mean OA levels between non-survivors and survivors (early 0.48 vs. 0.36, late 0.43 vs. 0.37, P > 0.5 for all).Conclusion
OA was detectable more frequently in APAP-ALF non-survivors but mean OA levels were not associated with survival. The routine clinical administration of N-acetyl cysteine could replenish GSH levels and prevent OA production. 相似文献126.
Induction of lipid metabolic enzymes during the endoplasmic reticulum stress response in plants 下载免费PDF全文
The endoplasmic reticulum (ER) stress response is a signal transduction pathway activated by the perturbation of normal ER metabolism. We used the maize (Zea mays) floury-2 (fl2) mutant and soybean (Glycine max) suspension cultures treated with tunicamycin (Tm) to investigate the ER stress response as it relates to phospholipid metabolism in plants. Four key phospholipid biosynthetic enzymes, including DG kinase and phosphatidylinositol (PI) 4-phosphate 5-kinase were up-regulated in the fl2 mutant, specifically in protein body fractions where the mutation has its greatest effect. The third up-regulated enzyme, choline-phosphate cytidylyltransferase, was regulated by fl2 gene dosage and developmental signals. Elevated accumulation of the fourth enzyme, PI 4-kinase, was observed in the fl2 endosperm and soybean cells treated with Tm. The activation of these phospholipid biosynthetic enzymes was accompanied by alterations in membrane lipid synthesis and accumulation. The fl2 mutant exhibited increased PI content in protein body membranes at 18 d after pollination and more than 3-fold higher triacylglycerol accumulation in the endosperm by 36 d after pollination. Incorporation of radiolabeled acetate into phospholipids in soybean culture cells increased by about 30% with Tm treatment. The coordinated regulation of ER stress related proteins and multiple components of phospholipid biosynthesis is consistent with signaling through a common pathway. We postulate that the plant ER stress response has an important role in general plant metabolism, and more specifically in integrating the synthesis of protein and lipid reserves to allow proper seed formation. 相似文献
127.
Hewett JW Kamm C Boston H Beauchamp R Naismith T Ozelius L Hanson PI Breakefield XO Ramesh V 《Journal of neurochemistry》2004,89(5):1186-1194
The torsins comprise a four-member family of AAA+ chaperone proteins, including torsinA, torsinB, torp2A and torp3A in humans. Mutations in torsinA underlie early onset torsion dystonia, an autosomal dominant, neurologically based movement disorder. TorsinB is highly homologous to torsinA with its gene adjacent to that for torsinA on human chromosome 9q34. Antibodies have been generated which can distinguish torsinA and torsinB from each other, and from the torps in human and rodent cells. TorsinB (approximately MW 38 kDa), like torsinA ( approximately MW 37 kDa), is an N-glycosylated protein and both reside primarily in the endoplasmic reticulum (ER) and nuclear envelope in cultured cells. Immunoprecipitation studies in cultured cells and human brain tissue indicate that torsinA and torsinB are associated with each other in cells. Overexpression of both wild-type torsinB and mutant torsinA lead to enrichment of the protein in the nuclear envelope and formation of large cytoplasmic inclusions. We conclude that torsinB and torsinA are localized in overlapping cell compartments within the same protein complex, and thus may carry out related functions in vivo. 相似文献
128.
129.
Nolen-Walston RD Kim CF Mazan MR Ingenito EP Gruntman AM Tsai L Boston R Woolfenden AE Jacks T Hoffman AM 《American journal of physiology. Lung cellular and molecular physiology》2008,294(6):L1158-L1165
Organ regeneration in mammals is hypothesized to require a functional pool of stem or progenitor cells, but the role of these cells in lung regeneration is unknown. Whereas postnatal regeneration of alveolar tissue has been attributed to type II alveolar epithelial cells (AECII), we reasoned that bronchioalveolar stem cells (BASCs) have the potential to contribute substantially to this process. To test this hypothesis, unilateral pneumonectomy (PNX) was performed on adult female C57/BL6 mice to stimulate compensatory lung regrowth. The density of BASCs and AECII, and morphometric and physiological measurements, were recorded on days 1, 3, 7, 14, 28, and 45 after surgery. Vital capacity was restored by day 7 after PNX. BASC numbers increased by day 3, peaked to 220% of controls (P<0.05) by day 14, and then returned to baseline after active lung regrowth was complete, whereas AECII cell densities increased to 124% of baseline (N/S). Proliferation studies revealed significant BrdU uptake in BASCs and AECII within the first 7 days after PNX. Quantitative analysis using a systems biology model was used to evaluate the potential contribution of BASCs and AECII. The model demonstrated that BASC proliferation and differentiation contributes between 0 and 25% of compensatory alveolar epithelial (type I and II cell) regrowth, demonstrating that regeneration requires a substantial contribution from AECII. The observed cell kinetic profiles can be reconciled using a dual-compartment (BASC and AECII) proliferation model assuming a linear hierarchy of BASCs, AECII, and AECI cells to achieve lung regrowth. 相似文献
130.
Kim Ju-Kon Duan Xiaolan Wu Ray Seok Soon Jong Boston Rebecca S. Jang In-Cheol Eun Moo-Young Nahm Baek Hie 《Molecular breeding : new strategies in plant improvement》1999,5(2):85-94
We have previously transformed rice (Oyrza sativa L.) with the maize ribosome-inactivating protein b-32 gene (Zmcrip3a) and
the phosphinothricin resistance gene (bar). In the present study, Southern blot hybridization analysis of 56 primary fertile
transformants resulted in distinct band patterns, indicating that all the transformants had been generated by independent
integration events and 30% of them contained a single copy of the transgene. Segregation analysis of 15 R0 plants revealed
that transgene was stably transmitted to their progenies and Southern blot band patterns of R1 progenies remained the same
as the corresponding parents, suggesting that all the loci of multiple integration events are genetically linked. Also, in
most of the lines, physical presence of the b-32 transgene co-segregated with the phosphinothricin- resistant phenotype, confirming
that the transgene is behaving as a normal locus in the genome. However, some of R1 seedlings that contained multiple copies
of the transgene became sensitive to phosphinothricin, indicating that its expression was silenced. Immunoblot analysis demonstrated
that b-32 protein was produced and the levels of expression differed in different lines, estimated to be 0.5–1% of total soluble
protein in the leaf tissues. In addition, the transgene-encoded protein was preferentially processed in germinating seeds
and young leaves of R2 transgenic plants in a way similar to that in maize kernels, suggesting that the processing mechanism
is conserved in the germination stage between rice and maize.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献