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134.
Evelyn Zeindl-Eberhart Sibylle Liebmann Peter Roman Jungblut Jens Mattow Monika Schmid Rosi Kerler Hartmut Manfred Rabes 《Amino acids》2011,41(2):415-425
Radiation-induced human papillary thyroid carcinomas (PTCs) show a high prevalence of fusions of the RET proto-oncogene to heterologous genes H4 (RET/PTC1) and ELE1 (RET/PTC3), respectively. In contrast to the normal membrane-bound RET protein, aberrant RET fusion proteins are constitutively active
oncogenic cytosolic proteins that can lead to malignant transformation of thyroid epithelia. To detect specific tumor-associated
protein changes that reflect the effect of RET/PTC fusion proteins, we analyzed normal thyroid tissues, thyroid tumors of
the RET/PTC1 and RET/PTC3 type and their respective lymph node metastases by a combination of high-resolution two-dimensional
electrophoresis and matrix-assisted laser desorption/ionization-mass spectrometry. PTCs without RET rearrangements served
as controls. Several cytoskeletal protein species showed quantitative changes in tumors and lymph node metastases harboring
RET/PTC1 or RET/PTC3. We observed prominent C-terminal actin fragments assumedly generated by protease cleavages induced due
to enhanced amounts of the active actin-binding protein cofilin-1. In addition, three truncated vimentin species, one of which
was proven to be headless, were shown to be highly abundant in tumors and metastases of both RET/PTC types. The observed protein
changes are closely connected with the constitutive activation of RET-rearranged oncoproteins and reflect the importance to
elucidate disease-related typical signatures on the protein species level. 相似文献
135.
Margaret Salmon Christian Salmon Alexa Bissinger Mundenga Mutendi Muller Alegnta Gebreyesus Haimanot Geremew Sarah Wendell Aklilu Azaza Maurice Salumu Nerys Benfield 《PloS one》2015,10(8)
This paper describes design of a low cost, ultrasound gel from local products applying aspects of Human Centered Design methodology. A multidisciplinary team worked with clinicians who use ultrasound where commercial gel is cost prohibitive and scarce. The team followed the format outlined in the Ideo Took Kit. Research began by defining the challenge "how to create locally available alternative ultrasound gel for a low-resourced environment? The "End-Users," were identified as clinicians who use ultrasound in Democratic Republic of the Congo and Ethiopia. An expert group was identified and queried for possible alternatives to commercial gel. Responses included shampoo, oils, water and cornstarch. Cornstarch, while a reasonable solution, was either not available or too expensive. We then sought deeper knowledge of locally sources materials from local experts, market vendors, to develop a similar product. Suggested solutions gleaned from these interviews were collected and used to create ultrasound gel accounting for cost, image quality, manufacturing capability. Initial prototypes used cassava root flour from Great Lakes Region (DRC, Rwanda, Uganda, Tanzania) and West Africa, and bula from Ethiopia. Prototypes were tested in the field and resulting images evaluated by our user group. A final prototype was then selected. Cassava and bula at a 32 part water, 8 part flour and 4 part salt, heated, mixed then cooled was the product design of choice. 相似文献
136.
Emanuela Ventrella Paweł Marciniak Zbigniew Adamski Grzegorz Rosiński Szymon Chowański Patrizia Falabella Laura Scrano Sabino A. Bufo 《Insect Science》2015,22(2):251-262
Glycoalkaloids, the biologically active secondary metabolites produced by Solanaceae plants, are natural defenses against animals, insects and fungi. In this paper, the effects of glycoalkaloids present in extracts of Solanaceae plants (potato, tomato and black nightshade) or pure commercial glycoalkaloids on the coleopteran Zophobas atratus F. were evaluated by in vitro and in vivo bioassays using heart experimental models. Each tested extract induced a dose‐dependent cardioinhibitory effect. The perfusion of Zophobas atratus semi‐isolated heart using the highest potato and tomato extract concentration (1 mmol/L) caused irreversible cardiac arrests, while extract from black nightshade produced fast but reversible arrests. Pure commercial glycoalkaloids caused similar but less evident effects compared with extracts. Our results showed that the bioactivity of tested compounds depended on their structure and suggested the existence of synergistic interactions when combinations of the main glycoalkaloids of potato and black nightshade were used for trials. Surprisingly, injection of tomato and potato extracts in 1‐day‐old pupae of Zophobas atratus induced reversible positive chronotropic effects and decreased the duration of the both phases (anterograde and retrograde) of the heart contractile activity. Furthermore, these extracts affected the amplitude of the heart contractions. 相似文献
137.
Raber J Rosi S Chakraborti A Fishman K Dayger C Davis MJ Villasana L Fike JR 《Radiation research》2011,176(4):521-526
Ionizing radiation reduces the numbers of neurons expressing activity-regulated cytoskeleton-associated protein (Arc) in the hippocampal dentate gyrus (DG). It is currently unclear if that change relates to cognitive function. We assessed the effects of 1 Gy of head-only ??Fe-particle irradiation on hippocampus-dependent and hippocampus-independent fear conditioning and determined how those changes related to Arc expression within the DG. Irradiated mice that did not receive tone-shock pairings on day 1 showed less freezing in the same context on a second day and a lower fraction of Arc-expressing neurons in the free (lower) blade of the DG than sham-irradiated mice. Those data suggested reduced hippocampus-dependent spatial habituation learning. Changes in Arc expression in the free blade correlated positively with freezing in mice that did not receive tone-shock pairings. However, irradiated mice that did receive tone-shock pairings showed enhanced contextual freezing but a reduced percentage of Arc-expressing neurons in the enclosed (upper) blade. Changes in Arc expression correlated negatively with freezing in mice that received tone-shock pairings. In animals receiving cued fear conditioning, radiation did not affect cognitive performance or the fractions of Arc-expressing neurons. While the relationship between Arc expression and cognitive performance is complex, our data suggest that radiation effects on hippocampus-dependent cognition might depend on the prominence (salience) of environmental stimuli and blade-specific Arc expression. 相似文献
138.
Peptides from the pyrokinin (PK) family are a large, structurally and functionally diverse group of the insect neuropeptides produced by neurosecretory cells of the insect nervous system. This family contains short and long peptides which share C-terminal -FXPRLa amino acid sequence. Pyrokinins regulate the visceral muscle contractions, pheromone biosynthesis, pupariation and diapause duration in insects. They are encoded by two genes PBAN and capa, which are mainly expressed in the suboesophageal ganglion. Peptides are then transported to the retrocerebral complex and released into haemolymph. Recent studies are focused on application of pyrokinins as biopesticides in the regulation of insect pests growth and development. 相似文献
139.
Grzegorz Rosiński Ignacy Korczyński Małgorzata Słocińska Robert Kuźmiński 《Insect Science》2011,18(2):160-165
Abstract The peptides proctolin, crustacean cardioactive peptide (CCAP) and FMRFamide, which are known to modulate insect muscle contractions, were assayed for their action on oviduct contractions in Hylobius abietis. A video microscopy technique and computer‐based method of data acquisition and analysis were used to investigate the effects of theses peptides on spontaneous contractions of continuously perfused oviducts. All three peptides tested stimulate spontaneous contraction activity of the pine weevil oviduct, increasing the frequency and amplitude of phasic contractions in a dose‐dependent manner. Proctolin is more potent as a stimulator than CCAP. For proctolin a threshold response of oviduct muscles is at concentration of peptide 10?11–10?10 mol/L and for CCAP at concentration range 10?10–10?9 mol/L. FMRFamide exerts a weak stimulatory effect on the oviduct, and at higher concentrations of the peptide (above 10?8 mol/L). The peptides exert different responses on oviduct contractions and they may play a role as functional regulators in such processes as egg movement and oviposition. 相似文献
140.
Campos MP Cechinel Filho V Silva RZ Yunes RA Monache FD Cruz AB 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(3-4):173-178
Piper solmsianum C. DC. var. solmsianum (Piperaceae) is a shrub commonly found in areas with wet tropical soils. Other Piper species have been used in folk medicine as antitumoral and antiseptic agents. We studied the crude methanolic extract, some organic fractions and compounds isolated from this plant for possible antimicrobial activity against Gram-positive and Gram-negative bacteria. The bioautographic assays disclosed three inhibition zones. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were determined showing excellent activity, particularly against the Gram-positive bacteria (Bacillus cereus, Staphylococcus aureus, Staphylococcus saprophyticus and Streptococcus agalactiae). It appears that the antimicrobial activity of Piper solmsianum is related mainly to the presence of conocarpan and eupomatenoid-5 (neolignans). However another, as yet unidentified, active compound could also be extracted from the plant. 相似文献