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31.
Hammer NA Hansen Tv Byskov AG Rajpert-De Meyts E Grøndahl ML Bredkjaer HE Wewer UM Christiansen J Nielsen FC 《Reproduction (Cambridge, England)》2005,130(2):203-212
Insulin-like growth factor-II mRNA-binding proteins 1, 2 and 3 (IMP1, IMP2 and IMP3) belong to a family of RNA-binding proteins implicated in mRNA localization, turnover and translational control. We examined their expression pattern during development of murine and human testis and ovaries. In the mouse, IMPs were expressed in male and female gonadal cells at embryonic day 12.5 (E12.5). From E16.5, IMP1 and IMP3 became restricted to the developing germ cells, whereas IMP2 expression persisted in the interstitial cells. In mature mouse and human ovaries, IMP1, IMP2 and IMP3 were detected in resting and growing oocytes and in the granulosa cells. In testis, IMP1 and IMP3 were found mainly in the spermatogonia, whereas IMP2 was expressed in the immature Leydig cells. Moreover, all three IMPs were detected in human semen. The developmental expression pattern of IMP1 and IMP3 in the human testis prompted us to examine their possible involvement in testicular neoplasia. IMPs were detected primarily in germ-cell neoplasms, including preinvasive testicular carcinoma in situ, classical and spermatocytic seminoma, and nonseminomas, with particularly high expression in undifferentiated embryonal carcinoma. The relative expression of IMP1, IMP2 and IMP3 varied among tumor types and only IMP1 was detected in all carcinoma in situ cells. Thus IMPs, and in particular IMP1, may be useful auxiliary markers of testicular neoplasia. 相似文献
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Polychlorinated naphthalenes in Swedish background air 总被引:1,自引:0,他引:1
Egebäck AL Wideqvist U Järnberg U Asplund L 《Environmental science & technology》2004,38(19):4913-4920
Polychlorinated naphthalenes (PCNs) with four to eight chlorines were studied in air collected at two background stations in Sweden, one southerly and one northerly. Air was sampled with a high-volume sampler, and gas-phase adsorbents and filters were analyzed separately. The sum of TeCNs to HxCNs in the gaseous phase ranged between 1 and 10 pg/m3 with significantly higher concentrations at the southern location Hoburgen. HpCNs and OCN were below the detection limit. The highest concentrations were found in two samples from Hoburgen with the air masses coming from SW and W and during warm weather (+11 degrees C). The lowest concentration was found in a sample from the northern location Ammarn?s at cold weather (-22 degrees C) when the air came from the east. A correlation was found between logP and 1/T indicating that temperature has a larger effect than location on the concentration in the gas phase. The TeCNs constituted 50-75% in the gaseous phase. In most filter samples TeCNs and PeCNs were below the limit of quantitation. PUF samples with air trajectories from W to NE had relatively higher concentrations of late eluting TeCNs and PeCNs, while in samples with winds from SE to S the early eluting congeners dominated. Samples with early eluting congeners were mainly collected at lower temperature. TriCNs constituted the dominant homologue group both in the gaseous and particulate phase of air samples as well as in bulk deposition from a rural monitoring station south of Stockholm. The octanol-air partition coefficient described the gas/particle interaction well for samples collected at temperatures down to -8 degrees C. 相似文献
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Small droplets appearing on the surface of alkali-silica reactive aggregates and on gel in cracks and air voids have been observed during microscopy of polished thin sections. On aggregates, the droplets are generally only observed if quartz is the major component. The location of the droplets in these aggregates are on and along the grain boundaries of quartz subgrains. The composition of droplets located on quartz and on “crystalline gel” has been analysed by SEM. The droplets on quartz consist mainly of sodium and minor potassium. The droplets on “crystalline gel” are rich in both sodium and potassium. Calcium is generally absent and silica low in all types of droplets. It is suggested that the droplets represent the liquid phase in equilibrium with the reaction product formed by alkali-silica reaction. 相似文献
36.
Andreas W. Sonesson Thomas H. Callisen Ulla M. Elofsson Hjalmar Brismar 《Journal of surfactants and detergents》2007,10(4):211-218
Detergency mechanisms of lipids from single cotton fibers were visualized by means of confocal laser scanning microscopy (CLSM).
Fibers were soiled with different types of lipids: olive oil, lard and tri-C10, and subsequently stained with the fluorescent probe Nile Red. A surfactant composition of 300 μM C12E6/LAS (1:2 mol%) was used to mimic the surfactants used in a common washing solution. It was evident from the captured image
series that the different kinds of soiling were removed by different mechanisms by the surfactants, depending on the fluidity
of the lipid. Roll-up was the main mechanism when removing olive oil, whereas emulsification (necking) and/or solubilization
were observed in the removal of lard and tri-C10. Only 20–25% of the olive oil remained after treatment with surfactants, which was much less compared to the solid fats where
roughly 50% remained at end of treatment. The effect of adding lipases to the detergent formulation was clearly seen, both
by an apparently higher rate of removal of olive oil but also using double injection when removing lard. A first injection
of only surfactants removed a certain part of the lard as emulsion droplets stuck onto the fiber. A second injection of both
lipases and surfactants was able to remove some of the preformed emulsion particles and reduce the overall remaining lard
content on the cotton fiber.
相似文献
Thomas H. CallisenEmail: |
37.
Margareta Hgg Ulla Hkkinen Jorma Kumpulainen Raija Ahvenainen Eero Hurme 《Journal of the science of food and agriculture》1998,77(4):519-526
The effects of preparation procedures and packaging on vitamin C, dietary fibre, sugars, ash and moisture contents were studied in prepeeled packaged potatoes during two cultivation seasons. The potato cultivars Bintje, Van Gogh and Nicola were studied. Potatoes of the Nicola cultivar had the highest initial vitamin C and sugar contents. Retention of nutrient contents in packaged, prepeeled potatoes was very good after a 7-day storage period. Vitamin C contents were higher in packaged potatoes than in fresh tubers when ascorbic acid was used in the washing solution but the levels decreased during the 7-day storage period. When calcium chloride was added as well into the washing solution vitamin C contents remained high throughout the storage period. These results show that it is possible to preserve the nutritional contents of packaged potatoes over a 7-day storage period. Cooking decreased vitamin C contents by about 30% and keeping the potatoes hot for 1 h after cooking decreased vitamin C contents a further 10%. © 1998 SCI. 相似文献
38.
Chronic obstructive pulmonary disease in patients with end‐stage kidney disease on hemodialysis 下载免费PDF全文
Louis L. Plesner Peder E. Warming Ture L. Nielsen Morten Dalsgaard Morten Schou Ulla Høst Casper Rydahl Lisbet Brandi Lars Køber Jørgen Vestbo Kasper Iversen 《Hemodialysis international. International Symposium on Home Hemodialysis》2016,20(1):68-77
The objectives of this study were to assess the prevalence of chronic obstructive pulmonary disease (COPD) in hemodialysis patients with spirometry and to examine the effects of fluid removal by hemodialysis on lung volumes. Patients ≥18 years at two Danish hemodialysis centers were included. Forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio were measured with spirometry before and after hemodialysis. The diagnosis of COPD was based on both the GOLD criteria and the lower limit of normal criteria. There were 372 patients in treatment at the two centers, 255 patients (69%) completed spirometry before dialysis and 242 of these (65%) repeated the test after. In the initial test, 117 subjects (46%) had airflow limitation indicative of COPD with GOLD criteria and 103 subjects (40.4%) with lower limit of normal criteria; COPD was previously diagnosed in 24 patients (9%). Mean FVC and FEV1 decreased mildly after dialysis (FVC: 2.84 to 2.79 L, P < 0.01. FEV1: 1.97 to 1.93 L, P < 0.01) Hemodialysis did not affect the FEV1/FVC ratio or number of subjects with airflow limitation indicative of COPD (113 vs. 120, P = 0.324; n = 242). COPD is a frequent and underdiagnosed comorbidity in patients on chronic hemodialysis. Spirometry should be considered in all patients on dialysis in order to address dyspnea adequately. Hemodialysis induced a small fall in mean FEV1 and FVC, which was more pronounced in patients with little or no fluid removal, but the FEV1/FVC ratio and the number of subjects with airflow limitation indicative of COPD were not affected by dialysis. 相似文献
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