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81.
Kathy Bailey Tahmineh Yazdi Umesh Masharani Blake Tyrrell Anthony Butch Fred Schaufele 《PloS one》2016,11(3)
Testosterone (T) and related androgens are performance enhancing drugs (PEDs) abused by some athletes to gain competitive advantage. To monitor unauthorized androgen abuse, doping control programs use mass spectrometry (MS) to detect androgens, synthetic anabolic-androgenic steroids (AASs) and their metabolites in an athlete’s urine. AASs of unknown composition will not be detected by these procedures. Since AASs achieve their anabolic effects by activating the Androgen Receptor (AR), cell-based bioassays that measure the effect of a urine sample on AR activity are under investigation as complementary, pan-androgen detection methods. We evaluated an AR BioAssay as a monitor for androgen activity in urine pre-treated with glucuronidase, which releases T from the inactive T-glucuronide that predominates in urine. AR BioAssay activity levels were expressed as ‘T-equivalent’ concentrations by comparison to a T dose response curve. The T-equivalent concentrations of androgens in the urine of hypogonadal participants supplemented with T (in whom all androgenic activity should arise from T) were quantitatively identical to the T measurements conducted by MS at the UCLA Olympic Analytical Laboratory (0.96 ± 0.22). All 17 AASs studied were active in the AR BioAssay; other steroids were inactive. 12 metabolites of 10 commonly abused AASs, which are used for MS monitoring of AAS doping because of their prolonged presence in urine, had reduced or no AR BioAssay activity. Thus, the AR BioAssay can accurately and inexpensively monitor T, but its ability to monitor urinary AASs will be limited to a period immediately following doping in which the active AASs remain intact. 相似文献
82.
The conodont fauna from the Devonian-Carboniferous Shahmirzad section, located in the Central Alborz Mountains (North Iran), have been studied mainly for biostratigraphic purposes. Some levels were barren of conodonts, whereas others yielded a not very abundant, but quite differentiated fauna. No conodonts have been found from the mainly terrigenous and shaly Geirud Formation, whereas representative of genera Bispathodus, Clydagnathus, Gnathodus, Hindeodus, Mehlina, Polygnathus, Protognathodus, Pseudopolygnathus and Siphonodella have been collected from the mainly calcareous overlaying Mobarak Formation. The fauna allowed to discriminate five biointervals, from the sulcata Zone to a “Lower typicus - anchoralis-latus interval” in the central part of the section, while the lower and upper parts cannot be zoned on the basis of conodonts. This paper is the first report on lowermost Carboniferous conodonts from the Mobarak Formation in central Alborz. 相似文献
83.
Yazdi M Ahnmark A William-Olsson L Snaith M Turner N Osla F Wedin M Asztély AK Elmgren A Bohlooly-Y M Schreyer S Lindén D 《Biochemical and biophysical research communications》2008,369(4):1065-1070
Glycerol-3-phosphate acyltransferase (GPAT) is involved in triacylglycerol (TAG) and phospholipid synthesis, catalyzing the first committed step. In order to further investigate the in vivo importance of the dominating mitochondrial variant, GPAT1, a novel GPAT1−/− mouse model was generated and studied. Female GPAT1−/− mice had reduced body weight-gain and adiposity when fed chow diet compared with littermate wild-type controls. Furthermore, GPAT1−/− females on chow diet showed decreased liver TAG content, plasma cholesterol and TAG levels and increased ex vivo liver fatty acid oxidation and plasma ketone bodies. However, these beneficial effects were abolished and the glucose tolerance tended to be impaired when GPAT1−/− females were fed a long-term high-fat diet (HFD). GPAT1-deficiency was not associated with altered whole body energy expenditure or respiratory exchange ratio. In addition, there were no changes in male GPAT1−/− mice fed either diet except for increased plasma ketone bodies on chow diet, indicating a gender-specific phenotype. Thus, GPAT1-deficiency does not protect against HFD-induced obesity, hepatic steatosis or whole body glucose intolerance. 相似文献
84.
Abdollah Ghasemian Mojtaba Tabatabaei Yazdi Zargham Sepehrizadeh Zohreh Tabatabaei Yazdi Gholamreza Zarrini 《World journal of microbiology & biotechnology》2009,25(5):773-779
A 1.6 kb gene encoding a cholesterol oxidase (choR) from a local isolate, Rhodococcus sp. PTCC 1633 was cloned into pET23a and the highly expressed recombinant enzyme was purified from the cell lysate of IPTG-induced
Escherichia coli BL21(DE3)pLysS with one-step absorption on cholesterol. The purified protein had a molecular mass of 55 kDa, isoelectric
point at about pH 9.0 and absorption peaks at 280, 380 and 460 nm, indicating that the enzyme is a flavoprotein. The optimum
pH and temperature for the recombinant enzyme were 7.0 and 50°C, respectively. Steady-state kinetic revealed that the cholesterol
oxidase had a K
m
of 32 μM. This study is the first report concerning expression and one-step purification of a gene encoding cholesterol oxidase
from Rhodococcus spp. This study revealed that this enzyme is a type II cholesterol oxidase. 相似文献
85.
86.
Documentation of use patterns of plants across national boundaries is of relevance in understanding the importance of plant resources to livelihood strategies of different ethnic groups. Plant resources have gained prominence as a natural asset through which families derive food, firewood, income, medicines and timber, enabling particularly poor communities to achieve self-sufficiency. The objective of this study was to investigate the trends in plant usage in South Africa and Zimbabwe. An ethnobotanical investigation was conducted between January 2012 and January 2013 in the Limpopo Province, South Africa and the Midlands Province, Zimbabwe. The study used questionnaire surveys and interviews with a total of 143 participants to explore plant use patterns in South Africa and Zimbabwe. A total of 98 plant species were identified, with Zimbabwe contributing 70 species and 47 species from South Africa. The uses were classified into 15 categories, major use categories were firewood, food plants, medicine and timber. Food plant was a major plant use category in Zimbabwe, contributing 55.1%, followed by medicinal plants (36.8%), firewood (35.7%) and timber (31.6%). In contrast, firewood was the major plant use category in South Africa, contributing 18.4%, followed by food plants (17.3%), medicinal (14.3%) and timber (1.0%). Comparison of the two countries demonstrated remarkable differences in plant use patterns. The results showed that rural households in Zimbabwe were more reliant on plant resources than their counterparts in South Africa. Such a trend could be attributed to a close relationship between the local people, and their natural and agricultural environment leading to a rich knowledge base on plants, plant use and related practices. This comparative analysis strengthens the firm belief that utilization of plant resources represents an important shared heritage, preserved over the centuries, which must be exploited in order to provide further new and useful body of ethnobotanical knowledge. 相似文献
87.
88.
Khalilpour Akbar Kilic Tugba Khalilpour Saba Álvarez Mario Moisés Yazdi Iman K. 《Applied microbiology and biotechnology》2017,101(2):475-491
Applied Microbiology and Biotechnology - In the post-genome age, proteomics is receiving significant attention because they provide an invaluable source of biological structures and functions at... 相似文献
89.
90.
Wither J Cai YC Lim S McKenzie T Roslin N Claudio JO Cooper GS Hudson TJ Paterson AD Greenwood CM Gladman D Pope J Pineau CA Smith CD Hanly JG Peschken C Boire G;CaNIOS Investigators Fortin PR 《Arthritis research & therapy》2008,10(5):R108-13