全文获取类型
收费全文 | 77篇 |
免费 | 2篇 |
出版年
2021年 | 2篇 |
2020年 | 4篇 |
2019年 | 1篇 |
2018年 | 2篇 |
2016年 | 1篇 |
2015年 | 1篇 |
2014年 | 4篇 |
2013年 | 5篇 |
2012年 | 5篇 |
2011年 | 5篇 |
2010年 | 2篇 |
2009年 | 4篇 |
2008年 | 7篇 |
2007年 | 4篇 |
2006年 | 1篇 |
2005年 | 2篇 |
2004年 | 1篇 |
2003年 | 2篇 |
2002年 | 2篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1997年 | 2篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1989年 | 2篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1973年 | 1篇 |
1923年 | 2篇 |
1920年 | 1篇 |
1911年 | 1篇 |
排序方式: 共有79条查询结果,搜索用时 15 毫秒
1.
Berthiaume Y.; Albertine K. H.; Grady M.; Fick G.; Matthay M. A. 《Journal of applied physiology》1989,67(5):1887-1897
We studied the rate, the routes, and the mechanisms for protein clearance from the air spaces and lungs of 20 unanesthetized sheep over 144 h. We instilled 100 ml of autologous serum labeled with 125I-albumin into one lung. At the end of 24, 48, 96, or 144 h, the lungs were removed and the residual native protein and 125I-albumin in the air spaces were determined by bronchoalveolar lavage. Also the fraction of the instilled 125I-albumin remaining in the rest of the lung was measured in the lung homogenate. Clearance of the 125I-albumin from the lung into the plasma, lymph, thyroid, urine, and feces was also determined. The removal of both the 125I-albumin and the native protein from the air spaces was slow, following a monoexponential decline. The removal rate of the 125I-albumin from the air spaces was slightly but significantly faster (1.6%/h) than the clearance rate of the native protein (0.9%/h). Clearance of the 125I-albumin from the lung also followed a slow monoexponential decline at a rate of 1.4%/h. At all time periods, 75% of the 125I-albumin remaining in the lung was located in the air spaces, thus indicating that the pulmonary epithelium is the principal barrier to protein clearance from the normal lung. Macrophages appeared to play a minor role in alveolar protein clearance because the quantity of 125I-albumin present in the phagocytic cells in the air spaces was less than 1% of the instilled 125I-albumin at all time periods. However, macrophages may play some role in protein clearance after 48 h because we visualized phagolysosomes in macrophages, and there was an increase in free iodine in lung lavage, urine, thyroid, and feces after 48 h. However, gel electrophoretic studies showed that most of the 125I-albumin was cleared from the lung as an intact molecule, although only 24.7 +/- 4.7% of the 125I-albumin was cleared by the lymphatics. 相似文献
2.
Amani Briki Karim Kabor Eric Olmos Sabine Bosselaar Fabrice Blanchard Michel Fick Emmanuel Guedon Frantz Fournier Stphane Delaunay 《Engineering in Life Science》2020,20(5-6):205-215
Corynebacterium glutamicum is well known as an important industrial amino acid producer. For a few years, its ability to produce organic acids, under micro‐aerobic or anaerobic conditions was demonstrated. This study is focused on the identification of the culture parameters influencing the organic acids production and, in particular, the succinate production, by this bacterium. Corynebacterium glutamicum 2262, used throughout this study, was a wild‐type strain, which was not genetically designed for the production of succinate. The oxygenation level and the residual glucose concentration appeared as two critical parameters for the organic acids production. The maximal succinate concentration (4.9 g L?1) corresponded to the lower kLa value of 5 h?1. Above 5 h?1, a transient accumulation of the succinate was observed. Interestingly, the stop in the succinate production was concomitant with a lower threshold glucose concentration of 9 g L?1. Taking into account this threshold, a fed‐batch culture was performed to optimize the succinate production with C. glutamicum 2262. The results showed that this wild‐type strain was able to produce 93.6 g L?1 of succinate, which is one of the highest concentration reported in the literature. 相似文献
3.
Fick L Mitchell D Fuller A 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2007,147(2):445-452
Long-acting neuroleptics commonly are used in wildlife management to decrease stress-related mortality in wild animals, but with possible effects on thermoregulation, which may contribute to residual morbidity and mortality. We investigated the effects of haloperidol (0.01, 0.1, 1 mg kg(-1), n=4), zuclopenthixol (0.1, 1, 10 mg kg(-1), n=4) and perphenazine (0.1, 1, 10 mg kg(-1), n=8), as well as control injections of sunflower oil, on body temperature and physical activity of laboratory goats under hot, cold and thermoneutral ambient temperatures. Implanted data loggers continuously recorded abdominal temperature, and data loggers attached externally on the foreleg recorded movement of unrestrained goats, in a climatic chamber at 35 degrees C, 10 degrees C and 22 degrees C. Cycling ambient temperature between 35 degrees C in daytime and 10 degrees C at night time caused a significant increase in amplitude of the circadian rhythm of body temperature in goats given sunflower oil (P=0.0012, unpaired t-test, n=8), but the administration of zuclopenthixol or perphenazine did not affect this change in amplitude (P>0.05, two-way ANOVA, n=4). Mean daily body temperature after administration of zuclopenthixol or perphenazine, and mean daily activity after zuclopenthixol administration, were not significantly different to those after control injections, at any ambient temperature, for the expected duration of drug activity (all P>0.05, two-way ANOVA, n=4). Thermal response indices, and mean activity, during heat, cold or thermoneutral exposure, of goats for 7 h after haloperidol injection, were not significantly different, at any dose or any ambient temperature, to those following control injections (all P>0.05, repeated measures ANOVA, n=4). Long-acting neuroleptics did not impair activity or thermoregulation of goats subjected to inescapable thermal challenges. 相似文献
4.
Järhult JD Muradrasoli S Wahlgren J Söderström H Orozovic G Gunnarsson G Bröjer C Latorre-Margalef N Fick J Grabic R Lennerstrand J Waldenström J Lundkvist A Olsen B 《PloS one》2011,6(9):e24742
Oseltamivir (Tamiflu®) is the most widely used drug against influenza infections and is extensively stockpiled worldwide as part of pandemic preparedness plans. However, resistance is a growing problem and in 2008–2009, seasonal human influenza A/H1N1 virus strains in most parts of the world carried the mutation H274Y in the neuraminidase gene which causes resistance to the drug. The active metabolite of oseltamivir, oseltamivir carboxylate (OC), is poorly degraded in sewage treatment plants and surface water and has been detected in aquatic environments where the natural influenza reservoir, dabbling ducks, can be exposed to the substance. To assess if resistance can develop under these circumstances, we infected mallards with influenza A/H1N1 virus and exposed the birds to 80 ng/L, 1 µg/L and 80 µg/L of OC through their sole water source. By sequencing the neuraminidase gene from fecal samples, we found that H274Y occurred at 1 µg/L of OC and rapidly dominated the viral population at 80 µg/L. IC50 for OC was increased from 2–4 nM in wild-type viruses to 400–700 nM in H274Y mutants as measured by a neuraminidase inhibition assay. This is consistent with the decrease in sensitivity to OC that has been noted among human clinical isolates carrying H274Y. Environmental OC levels have been measured to 58–293 ng/L during seasonal outbreaks and are expected to reach µg/L-levels during pandemics. Thus, resistance could be induced in influenza viruses circulating among wild ducks. As influenza viruses can cross species barriers, oseltamivir resistance could spread to human-adapted strains with pandemic potential disabling oseltamivir, a cornerstone in pandemic preparedness planning. We propose surveillance in wild birds as a measure to understand the resistance situation in nature and to monitor it over time. Strategies to lower environmental levels of OC include improved sewage treatment and, more importantly, a prudent use of antivirals. 相似文献
5.
Jerker Vinterstare Christer Brnmark P. Anders Nilsson R. Brian Langerhans Olof Berglund Jennie
rjes Tomas Brodin Jerker Fick Kaj Hulthn 《Ecology and evolution》2021,11(14):9435
Predator‐inducible defenses constitute a widespread form of adaptive phenotypic plasticity, and such defenses have recently been suggested linked with the neuroendocrine system. The neuroendocrine system is a target of endocrine disruptors, such as psychoactive pharmaceuticals, which are common aquatic contaminants. We hypothesized that exposure to an antidepressant pollutant, fluoxetine, influences the physiological stress response in our model species, crucian carp, affecting its behavioral and morphological responses to predation threat. We examined short‐ and long‐term effects of fluoxetine and predator exposure on behavior and morphology in crucian carp. Seventeen days of exposure to a high dose of fluoxetine (100 µg/L) resulted in a shyer phenotype, regardless of the presence/absence of a pike predator, but this effect disappeared after long‐term exposure. Fluoxetine effects on morphological plasticity were context‐dependent as a low dose (1 µg/L) only influenced crucian carp body shape in pike presence. A high dose of fluoxetine strongly influenced body shape regardless of predator treatment. Our results highlight that environmental pollution by pharmaceuticals could disrupt physiological regulation of ecologically important inducible defenses. 相似文献
6.
Levonorgestrel is a synthetic progesterone commonly used in pharmaceuticals (e.g., in contraceptives). It is found in sewage treatment plant effluents at concentrations up to 30 ng/L and was recently shown to pose a threat to egg laying in fish. Information on the susceptibility of adult amphibians to progestin toxicity is lacking. The present study aimed to 1) characterize progestogenic effects on the full cycle of oogenesis (egg development) in frogs and 2) determine female amphibians' susceptibility to reproductive impacts from progestogenic compounds in the environment. Sexually mature female Xenopus tropicalis were exposed to levonorgestrel via the surrounding water for 7 days (0, 51, or 307 ng/L) or 28 days (0, 1.3, 18, 160, or 1240 ng/L). Their ovaries were analyzed histologically with respect to frequencies of immature (in early meiotic prophase I), previtellogenic, vitellogenic, mature, and atretic oocytes. The 28-day exposure caused reduced proportions of oocytes at immature, vitellogenic, and mature stages, and increased proportions of previtellogenic oocytes compared with the control. The lowest tested concentration, 1.3 ng/L, increased the proportions of previtellogenic oocytes and reduced the proportions of vitellogenic oocytes, indicating inhibited vitellogenesis. The present study shows that progestin concentrations found in the aquatic environment impaired oogenesis in adult frogs. Our results indicate that progestogenic effects on oocyte development include interrupted germ cell progression into meiosis and inhibited vitellogenesis. Considering the crucial role of oogenesis in female fertility, our results indicate that progestogenic pollutants may pose a threat to reproduction in wild amphibian populations. 相似文献
7.
8.
9.
Susan Singer John Sollinger Sonja Maki Jason Fishbach Brad Short Catherine Reinke Jennifer Fick Laura Cox Andrew McCall Heidi Mullen 《The Botanical review》1999,65(4):385-410
We are characterizing a suiteof Pisum sativum mutants that alter inflorescence architecture to construct a model for the genetic regulation of inflorescence development
in a plant with a compound raceme. Such a model, when compared with those created forAntirrhinum majus andArabidopsis thaliana, both of which have simple racemes, should provide insight into the evolution of the development of inflorescence architecture.
The highly conserved nature of cloned genes that regulate reproductive development in plants and the morphological similarities
among our mutants and those identified inA. majus andA. thaliana enhance the probability that a developmental genetics approach will be fruitful. Here we describe sixP. sativum mutants that affect morphologically and architecturally distinct aspects of the inflorescence, and we analyze interactions
among these genes. Both vegetative and inflorescence growth of the primary axis is affected byUNIFOLIA TA, which is necessary for the function ofDETERMINATE (DET).DET maintains indeterminacy in the first-order axis. In its absence, the meristem differentiates as a stub covered with epidermal
hairs.DET interacts withVEGETATIVE1 (VEG1).VEG1 appears essential for second-order inflorescence (I2) development.veg1 mutants fail to flower or differentiate the I2 meristem into a rudimentary stub,det veg1 double mutants produce true terminal flowers with no stubs, indicating that two genes must be eliminated for terminal flower
formation inP. sativum, whereas elimination of a single gene accomplishes this inA. thaliana andA. majus. NEPTUNE also affects I2 development by limiting to two the number of flowers produced prior to stub formation. Its role is independent ofDET, as indicated by the additive nature of the double mutantdet nep. UNI, BROC, and PIM all play roles in assigning floral meristem identity to the third-order branch.pim mutants continue to produce inflorescence branches, resulting in a highly complex architecture and aberrant flowers.uni mutants initiate a whorl of sepals, but floral organogenesis is aberrant beyond that developmental point, and the double
mutantuni pim lacks identifiable floral organs. A wild-type phenotype is observed inbroc plants, butbroc enhancesthe pim phenotype in the double mutant, producing inflorescences that resemble broccoli. Collectively these genes ensure that only
the third-order meristem, not higher- or lower-order meristems, generates floral organs, thus precisely regulating the overall
architecture of the plant.
Gene symbols used in this article: For clarity a common symbolization is used for genes of all species discussed in this article.
Genes are symbolized with italicized capital letters. Mutant alleles are represented by lowercase, italicized letters. In
both cases, the number immediately following the gene symbol differentiates among genes with the same symbol. If there are
multiple alleles, a hyphen followed by a number is used to distinguish alleles. Protein products are represented by capital
letters without italics. 相似文献
10.
Ben Fick Daniel W. Stover Ruth L. Chimenti Mederic M. Hall 《The Iowa orthopaedic journal》2021,41(2):82
BackgroundUltrasound guided tenotomy (USGT) is a minimally invasive treatment option for patients with chronic tendinopathy. There are conflicting findings in the literature with some studies reporting severe complications and others reporting none. This variability is likely due to the small sample sizes of previous studies. We aimed to evaluate the risks associated with USGT and outcomes across multiple tendinopathy/fasciopathy sites in a large clinical sample.MethodsPatients who had USGT were identified by retrospective review of charts. Complications, satisfaction, and outcomes (pain, quality of life) were assessed at baseline prior to the procedure (outcomes only), short-term follow up, and long term follow up.ResultsA total of 262 patients with 289 procedures were identified through chart review. There was a low complication rate of 0.7% including one superficial wound infection and one case of wound hypersensitivity. The majority of patients reported improvement in pain by short-term and long-term follow-up and improvement in function by long-term follow-up. The majority of responders reported being either ‘very satisfied’ or ‘somewhat satisfied’ with the procedure at short-term follow-up.ConclusionThis study found that USGT is a safe procedure with a low complication rate in a heterogeneous sample. Study findings provide preliminary evidence on the utility of USGT to reduce pain and improve function with a high rate of patient satisfaction.Level of Evidence: IV 相似文献