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311.
Retinitis pigmentosa is a highly heterogeneous form of inherited blindness which affects more than 1.3 million individuals worldwide. The RP17 form of the disease is caused by an arginine to tryptophan (R14W) mutation in the signal sequence of carbonic anhydrase IV (CAIV). While CAIV is expressed in the choriocapillaries of the eye and renal epithelium, the R14W mutation results in an exclusively ocular phenotype in affected individuals. In order to investigate the mechanism of disease in RP17 and the lack of kidney phenotype, we compared the subcellular localization and post‐translational processing of wild‐type (WT)‐ and mutant‐CAIV in three cell types. We show using immunocytochemistry that unlike WT CAIV which is transported to the plasma membrane of transfected COS‐7 and HT‐1080 cells, the R14W mutant CAIV is retained in the endoplasmic reticulum. Western blot analyses further reveal that whereas the WT CAIV is processed to its mature form in both these cell lines, significant levels of the R14W mutant protein remain in its immature form. Importantly, flow cytometry experiments demonstrate that compared to WT CAIV protein, expression of specifically the R14W CAIV results in an S and G2/M cell‐cycle block, followed by apoptosis. Interestingly, when the above experiments were repeated in the human embryonic kidney cell line, HEK‐293, strikingly different results were obtained. These cells were unaffected by the expression of the R14W mutant CAIV and were able to process the mutant and WT protein equally effectively. This study has important implications for our understanding of the RP17 phenotype. J. Cell. Biochem. 111: 735–741, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
312.
Ashraf M.A. Mashaly Ashraf M. Ahmed Mohammed S. Al-Khalifa Túlio M. Nunes E. David Morgan 《Biochemical Systematics and Ecology》2010
The major volatile compounds in the poison glands of two Monomorium ant species from Saudi Arabia have been identified. Monomorium niloticum and Monomorium najrane both contain mixtures of alkyl- and alkenyl-pyrrolidines and -pyrrolines in their venom glands but no Dufour gland volatile compounds were detected. Monomorium mayri showed neither Dufour gland compounds nor venom components detectable by gas chromatography. 相似文献
313.
Ami Bachar Ashraf Al-Ashhab M. Ines M. Soares Menachem Y. Sklarz Roey Angel Eugene D. Ungar Osnat Gillor 《Microbial ecology》2010,60(2):453-461
The exploration of spatial patterns of abundance and diversity patterns along precipitation gradients has focused for centuries
on plants and animals; microbial profiles along such gradients are largely unknown. We studied the effects of soil pH, nutrient
concentration, salinity, and water content on bacterial abundance and diversity in soils collected from Mediterranean, semi-arid,
and arid sites receiving approximately 400, 300, and 100 mm annual precipitation, respectively. Bacterial diversity was evaluated
by terminal restriction fragment length polymorphism and clone library analyses and the patterns obtained varied with the
climatic regions. Over 75% of the sequenced clones were unique to their environment, while ∼2% were shared by all sites, yet,
the Mediterranean and semi-arid sites had more common clones (∼9%) than either had with the arid site (4.7% and 6%, respectively).
The microbial abundance, estimated by phospholipid fatty acids and real-time quantitative PCR assays, was significantly lower
in the arid region. Our results indicate that although soil bacterial abundance decreases with precipitation, bacterial diversity
is independent of precipitation gradient. Furthermore, community composition was found to be unique to each ecosystem. 相似文献
314.
315.
Ali MA Ismail R Choon TS Yoon YK Wei AC Pandian S Kumar RS Osman H Manogaran E 《Bioorganic & medicinal chemistry letters》2010,20(23):7064-7066
Series of pyrolidine analogues were synthesized and examined as acetylcholinesterase (AChE) inhibitors. Among the compounds, compounds 4k and 6k were the most potent inhibitors of the series. Compound 4k, showed potent inhibitory activity against acetyl cholinesterase enzyme with IC(50) 0.10 μmol/L. Pyrolidine analogues might be potential acetyl cholinesterase agents for AD. 相似文献
316.
Gayle E. Derfus Daniel Abramzon Meg Tung David Chang Robert Kiss Ashraf Amanullah 《Biotechnology progress》2010,26(1):284-292
Mammalian cell‐based bioprocesses are used extensively for production of therapeutic proteins. Off‐line monitoring of such cultivations via manual sampling is often labor‐intensive and can introduce operator‐dependent error into the process. An integrated multi‐functional off‐line analyzer, the BioProfile FLEX (NOVA Biomedical, Waltham MA) has been developed, which combines the functionality of three off‐line analyzers (a cell counter, an osmometer, and a gas/electrolyte & nutrient/metabolite bio‐profile analyzer) into one device. In addition, a novel automated sampling system has also been developed that allows the BioProfile FLEX to automatically analyze the culture conditions in as many as ten bioreactors. This is the first report on the development and function of this integrated analyzer and an auto‐sampler prototype for monitoring of mammalian cell cultures. Evaluation of the BioProfile FLEX was conducted in two separate laboratories and involved two BioProfile FLEX analyzers and two sets of reference analyzers (Nova BioProfile 400, Beckman‐Coulter Vi‐Cell AS, and Advanced Instruments Osmometer 3900), 13 CHO cell lines and over 20 operators. In general, BioProfile FLEX measurements were equivalent to those obtained using reference analyzers, and the auto‐sampler did not alter the samples it provided to the BioProfile FLEX. These results suggest that the system has the potential to dramatically reduce the manual labor involved in monitoring mammalian cell bioprocesses without altering the quality of the data obtained, and integration with a bioreactor control system will allow feedback control of parameters previously available only for off‐line monitoring. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 相似文献
317.
Lan Wei Aisha David Ron S. Duman Hymie Anisman Arie Kaffman 《Hormones and behavior》2010,57(4-5):396-404
A better understanding of the molecular and cellular mechanisms by which early life stress (ELS) modifies brain development and adult behavior is necessary for diagnosing and treating psychopathology associated with exposure to ELS. For historical reasons, most of the work in rodents has been done in rats and attempts to establish robust and reproducible paradigms in the mouse have proven to be challenging. Here we show that under normal rearing conditions, increased levels of postnatal maternal care are associated with a decrease in anxiety-like behavior in BALB/cByj offspring. Brief daily pup-dam separation (BDS) during the postnatal period was associated with increased postnatal maternal care but was surprisingly associated with increased anxiety-like behavior in adult offspring, providing the first example in which offspring receiving higher levels of postnatal maternal care are more anxious in adulthood. Plasma corticosterone levels were elevated in BDS pups even 3 h after the pups were reunited with the dam, suggesting that this paradigm represents a form of early life stress. We also show that levels of total RNA and DNA in the hippocampus reach a peak at postnatal day 14 and that exposure to BDS seems to inhibit this developmental growth spurt. We propose that exposure to stress during the postnatal period overrides the ability of high levels of postnatal maternal care to program anxiety-like behavior by inhibiting the normal growth spurt that characterizes this period. 相似文献
318.
Background: The aim of this study was to investigate the prevalence of resistances in Helicobacter pylori against commonly used antibiotics including metronidazole, clarithromycin, amoxicillin, and tetracycline in Iranian patients. Methods: H. pylori isolates were collected from gastric biopsies from patients referred for upper gastrointestinal endoscopy at Tooba Medical Center, Sari, Iran, from 2007 to 2010. None of them had been using antibiotics for at least 8 months. H. pylori was identified based on morphological shape and positive biochemical tests for catalase, oxidase, and urease activity. Antibiotic resistance for metronidazole, clarithromycin, amoxicillin, and tetracycline was investigated by using epsilometer test. Resistance was defined by minimal inhibitory concentration (MIC) > 0.5 mg/L for amoxicillin (AMX), >4 mg/L for tetracycline (TET), >8 mg/L for metronidazole (MTZ), and >1 mg/L for clarithromycin (CLR). Results: Strains were collected from 132 patients, mean age 45.8 years, 52 (39%) were women. Patients had diverse diagnoses: gastritis 42 (31.8%), duodenal ulcer 45 (34%), gastric cancer 15 (11.3%), or gastric ulcer 30 (22.7%). The prevalences of resistance of H. pylori strains isolated from the patients were 73.4% for metronidazole, 30% for clarithromycin, 6.8% for amoxicillin, and 9% for tetracycline. Twenty‐eight (21.2%) were double resistant to MTZ‐CLR, 16 (12.1%) showed triple resistance to MTZ‐CLR‐AMX, and 8 (6%) were resistant to all four tested antibiotics (MTZ‐CLR‐AMX‐TET). No associations were detected between multiple resistant strains and clinical manifestations (p > .05). Conclusions: The prevalence of H. pylori antibiotic resistance to metronidazole and clarithromycin was high in Iran consistent with the reported low success rates for H. pylori treatment in this country. 相似文献
319.
Wheat production in Pakistan is seriously constrained due to rust diseases and stripe rust (yellow) caused by Puccinia striiformis f. sp. tritici, which could limit yields. Thus development and cultivation of genetically diverse and resistant varieties is the most sustainable
solution to overcome these diseases. The first objective of the present study was to evaluate 100 Pakistan wheat cultivars
that have been grown over the past 60 years. These cultivars were inoculated at the seedling stage with two virulent stripe
rust isolates from the United States and two from Pakistan. None of the wheat cultivars were resistant to all tested stripe
rust isolates, and 16% of cultivars were susceptible to the four isolates at the seedling stage. The data indicated that none
of the Pakistan wheat cultivars contained either Yr5 or Yr15 genes that were considered to be effective against most P. striiformis f. sp. tritici isolates from around the world. Several Pakistan wheat cultivars may have gene Yr10, which is effective against isolate PST-127 but ineffective against PST-116. It is also possible that these cultivars may
have other previously unidentified genes or gene combinations. The second objective was to evaluate the 100 Pakistan wheat
cultivars for stripe rust resistance during natural epidemics in Pakistan and Washington State, USA. It was found that a higher
frequency of resistance was present under field conditions compared with greenhouse conditions. Thirty genotypes (30% of germplasms)
were found to have a potentially high temperature adult plant (HTAP) resistance. The third objective was to determine the
genetic diversity in Pakistan wheat germplasms using molecular markers. This study was based on DNA fingerprinting using resistance
gene analog polymorphism (RGAP) marker analysis. The highest polymorphism detected with RGAP primer pairs was 40%, 50% and
57% with a mean polymorphism of 36%. A total of 22 RGAP markers were obtained in this study. RGAP, simple sequence repeat
(SSR) and sequence tagged site (STS) markers were used to determine the presence and absence of some important stripe rust
resistance genes, such as Yr5, Yr8, Yr9, Yr15 and Yr18. Of the 60 cultivars analyzed, 17% of cultivars showed a RGAP marker band for Yr9 and 12% of cultivars exhibited the Yr18 marker band. No marker band was detected for Yr5, Yr8 and Yr15, indicating a likely absence of these genes in the tested Pakistan wheat cultivars. Cluster analysis based on molecular and
stripe rust reaction data is useful in identifying considerable genetic diversity among Pakistan wheat cultivars. The resistant
germplasms identified with 22 RGAP markers and from the resistance evaluations should be useful in developing new wheat cultivars
with stripe rust resistance. 相似文献
320.
Human bronchial epithelial cells are needed for cell models of disease and to investigate the effect of excipients and pharmacologic agents on the function and structure of human epithelial cells. Here we describe in detail the method of growing bronchial epithelial cells from bronchial airway tissue that is harvested by the surgeon at the times of lung surgery (e.g. lung cancer or lung volume reduction surgery). With ethics approval and informed consent, the surgeon takes what is needed for pathology and provides us with a bronchial portion that is remote from the diseased areas. The tissue is then used as a source of explants that can be used for growing primary bronchial epithelial cells in culture. Bronchial segments about 0.5-1cm long and ≤1cm in diameter are rinsed with cold EBSS and excess parenchymal tissue is removed. Segments are cut open and minced into 2-3mm3 pieces of tissue. The pieces are used as a source of primary cells. After coating 100mm culture plates for 1-2 hr with a combination of collagen (30 μg/ml), fibronectin (10 μg/ml), and BSA (10 μg/ml), the plates are scratched in 4-5 areas and tissue pieces are placed in the scratched areas, then culture medium (DMEM/Ham F-12 with additives) suitable for epithelial cell growth is added and plates are placed in an incubator at 37°C in 5% CO2 humidified air. The culture medium is changed every 3-4 days. The epithelial cells grow from the pieces forming about 1.5 cm diameter rings in 3-4 weeks. Explants can be re-used up to 6 times by moving them into new pre-coated plates. Cells are lifted using trypsin/EDTA, pooled, counted, and re-plated in T75 Cell Bind flasks to increase their numbers. T75 flasks seeded with 2-3 million cells grow to 80% confluence in 4 weeks. Expanded primary human epithelial cells can be cultured and allowed to differentiate on air-liquid interface. Methods described here provide an abundant source of human bronchial epithelial cells from freshly isolated tissues and allow for studying these cells as models of disease and for pharmacology and toxicology screening.Download video file.(144M, mp4) 相似文献