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排序方式: 共有730条查询结果,搜索用时 15 毫秒
71.
Holmberg A Fogel J Albertsson E Fick J Brown JN Paxéus N Förlin L Johnsson JI Larsson DG 《Journal of hazardous materials》2011,187(1-3):596-599
Citalopram is one of several selective serotonin reuptake inhibitors (SSRIs) commonly found in treated sewage effluents. Accordingly, there are concerns about possible adverse effects of SSRIs on aquatic organisms, particularly behavioural effects similar to those associated with SSRI use in humans. Rainbow trout fry and adult male guppies were therefore exposed to waterborne citalopram, ranging from environmentally relevant to high concentrations (1, 10, 100 μg/L) for 3-7 days. Under these experimental conditions citalopram does not appear to cause significant effects on aggression in rainbow trout fry or on sexual behaviour in male guppies. This may be explained by a relatively low uptake of citalopram from water to fish. 相似文献
72.
Wanwan Qiu Jenny Gehlen Margherita Bernero Christian Gehre Gian Nutal Schädli Ralph Müller Xiao-Hua Qin 《Advanced functional materials》2023,33(20):2214393
Tomographic volumetric bioprinting (VBP) enables fast photofabrication of cell-laden hydrogel constructs in one step, addressing the limitations of conventional layer-by-layer additive manufacturing. However, existing biomaterials that fulfill the physicochemical requirements of VBP are limited to gelatin-based photoresins of high polymer concentrations. The printed microenvironments are predominantly static and stiff, lacking sufficient capacity to support 3D cell growth. Here a dynamic resin based on thiol–ene photo-clickable polyvinyl alcohol (PVA) and thermo-sensitive sacrificial gelatin for fast VBP of functional ultrasoft cell-laden hydrogel constructs within 7–15 s is reported. Using gelatin allows VBP of permissive hydrogels with low PVA contents of 1.5%, providing a stress-relaxing environment for fast cell spreading, 3D osteogenic differentiation of embedded human mesenchymal stem cells and matrix mineralization. Additionally, site-specific immobilization of molecules-of-interest inside a PVA hydrogel is achieved by 3D tomographic thiol–ene photopatterning. This technique may enable spatiotemporal control of cell-material interactions and guides in vitro tissue formation using programmed cell-friendly light. Altogether, this study introduces a synthetic dynamic photoresin enabling fast VBP of functional ultrasoft hydrogel constructs with well-defined physicochemical properties and high efficiency. 相似文献
73.
74.
The effects of ration on postprandial serum glucose and insulin were detemined in 12 lactating Holstein cows. Six were fed a high grain ration of 15% hay and 85% concentrate (dry basis) and the other six a control ration of 55% corn silage, 10% hay and 35% concentrate. High grain feeding increased glucose and insulin at all hours postfeeding as compared to control cows. In the cows fed high grain, glucose increased from 63.3 to 72.2 mg/100 ml and insulin from 19.2 to 25.6 mu units/ml serum just before feeding to 3 h postfeeding. Values for 2, 3, and 4 h samples were greater than for other sampling time. Serum glucose was 55.5 mg/100 ml at 1 h in control cows which was above other sample. Serum insulin followed a pattern similar to glucose in controls but was not signigicantly different with time. The blood changes due to high grain feeding are probably related to low milk fat production. 相似文献
75.
BE Roggo F Petersen R Delmendo HB Jenny HH Peter J Roesel 《Canadian Metallurgical Quarterly》1994,47(2):136-142
In the course of a screening program for HIV-1 protease inhibiting activity, six new homologues of 3-alkanoyl-5-hydroxymethyl tetronic acids (1 approximately 6) and the known natural product resistomycin (7) were isolated from cultures of the Actinomycete strain DSM 7357. The substituted tetronic acids belong to a recently described structural class of secondary metabolites. The HIV-1 activity of resistomycin (7) has not been reported before. 相似文献
76.
77.
Kopta Stephen Mark; Howard Kenneth I.; Lowry Jenny L.; Beutler Larry E. 《Canadian Metallurgical Quarterly》1994,62(5):1009
Using the psychotherapy dosage model in which effect was probability of recovery, this study compared treatment response rates for psychological symptoms. Symptom checklists were administered to 854 psychotherapy outpatients at intake and during treatment. 62 symptoms were grouped into 3 classes on the basis of probit analysis results. Chronic distress symptoms demonstrated the fastest average response rate, whereas characterological symptoms demonstrated the slowest. Acute distress symptoms showed the highest average percentage of patients recovered across doses. A typical outpatient needed about a year of psychotherapy to have a 75% chance of symptomatic recovery. The model holds promise for establishing guidelines for the financing of psychotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Crosson Bruce; Sartor Klaus J.; Jenny Arthur B.; Nabors Nina A.; Moberg Paul J. 《Canadian Metallurgical Quarterly》1993,7(2):193
The mesial temporal and lateral frontal lobes were the most common sites of parenchymal abnormality on magnetic resonance imaging (MRI) scans for 12 patients with chronic traumatic brain injury (TBI). Ventricular widening was also common, and 3 patients showed increased size of the upper third ventricle. Of 10 right-handed TBI patients with no evidence of learning disability, 6 showed dominant temporal lesions and 3 showed an increase in the size of the upper third ventricle. Only patients with dominant temporal lesions (4 of 6) exceeded the normal confidence interval (based on 20 non-TBI controls) for intrusion errors on delay trials of the California Verbal Learning Test (CVLT), though other patients also demonstrated impaired recall. The pattern of increased intrusions during CVLT delay trials was confirmed in non-TBI patients who had undergone dominant temporal surgery or had dominant or bilateral temporal lesions, even when frontal changes could be ruled out. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
80.
Distinct roles for the mammalian A-type cyclins during oogenesis 总被引:2,自引:0,他引:2
Persson JL Zhang Q Wang XY Ravnik SE Muhlrad S Wolgemuth DJ 《Reproduction (Cambridge, England)》2005,130(4):411-422
There are two A-type cyclins in higher vertebrates, cyclin A1 and A2. Targeted mutagenesis has shown that cyclin A2 is essential for early embryonic development while cyclin A1 is required only for male meiosis. The embryonic lethality of cyclin A2 knockout mice has obviated understanding its role in other aspects of mammalian development, including the germ line. We reported previously that cyclin A2 expression in the male germ line is consistent with a role in both mitotic and meiotic cell cycles. Using in situ hybridization and immunohistochemistry, we now observe high levels of cyclin A2 in granulosa cells and less-abundant but readily detectable expression in ovarian and ovulated oocytes. A decrease in cyclin A2 protein was observed in oocytes from embryonic stages to post-natal and adult ovaries. Interestingly, cyclin A2 protein was nuclear in oocytes from embryonic day 13.5 to 15.5, changing to largely cytoplasmic in oocytes from embryonic day 16.5 to post-natal and adults. Readily detectable expression of the cyclin-dependent kinases Cdk1 and Cdk2, two common partners for the A-type cyclins, was observed in granulosa cells and oocytes at all stages of folliculogenesis. Cdk1 was predominantly cytoplasmic, whereas Cdk2 was both cytoplasmic and nuclear in oocytes. No cyclin A1 expression, at either the mRNA level or the protein level was detected in either embryonic or adult ovaries, consistent with the full fertility observed in female cyclin A1-deficient mice. These results suggest that in the female germ line, cyclin A2 but not cyclin A1 has distinct roles in both mitosis and meiosis. 相似文献