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11.
Asiye İzem Sandal Hatice Şenlikci Merve Yılmazer Burcu Kartal Bedia Palabıyık Özen Banu Özdaş 《Andrologia》2021,53(5):e14032
The aim of the study was to investigate the efficiency of ram seminal plasma and fetal calf serum on freezing of buck semen. Twenty ejaculates were collected using an electro-ejaculator and split into six groups. While FCS additive was not used in A1, A2 and A3 groups, 10% FCS was added to B1, B2 and B3 groups. These groups were then edited according to whether the buck or ram SP was involved. The design of the groups was done as follows: Group A1 (control 1), group A2 without buck SP, group A3 containing ram SP instead of buck SP. Groups B1 (control 2), B2 and B3 were the FCS added forms of these groups. Progressive sperm motility percentages in Group A1 and Group B2 were found to be higher when compared to the lowest Group B3. There were no significant differences between the groups in neither the levels of reactive oxygen species nor the enzyme and glutathione activities. In conclusion, the lack of statistical difference between the groups suggested that despite the supplements used but only when the buck spermatozoa structure was healthy, the cell could preserve acrosome, DNA and the integrity of membrane. 相似文献
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Lue?en Henrik. L. de Leeuw Bas. J. Langeme?er Mariska W. E. de Boer A. G. Verhoef J. Coos. Junginger Hans E. 《Pharmaceutical research》1996,13(11):1668-1672
Purpose. To evaluate the effect of the crosslinked poly(acrylate) carbomer 934P (C934P) and its freeze-dried neutralized sodium salt (FNaC934P) as well as chitosan hydrochloride on the intestinal absorption of the peptide drug buserelin.
Methods. Buserelin was applied intraduodenally in control buffer, 0.5% (w/v) C934P, 0.5% (w/v) FNaC934P, 1.5% (w/v) chitosan hydrochloride or FNaC934P/chitosan hydrochloride (1:1 (v/v)) mixture in rats.
Results. All polymer preparation showed a statistically significant improvement of buserelin absorption compared to the control solution. The absolute bioavailabilities for the different polymer preparations were: control, 0.1%; 0.5% FNaC934P, 0.6%; 0.5% C934P, 2.0%; chitosan hydrochloride, 5.1% and FNaC934P/chitosan hydrochloride (1:1 (v/v)) mixture, 1.0%. The higher bioavailability with chitosan hydrochloride compared to C934P and FNaC934P indicates that for buserelin the intestinal transmucosal transport enhancing effect of the polymer plays a more dominant role than the protection against proteases such as -chymotrypsin.
Conclusions. The mucoadhesive polymers carbomer 934P and chitosan hydrochloride are able to enhance the intestinal absorption of buserelin in vivo in rats, and may therefore be promising excipients in peroral delivery systems for peptide drugs. 相似文献
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We report the singular case of an exceptionally large giant communicating artery aneurysm successfully treated with a direct surgical approach. The clinical presentation was a relatively short history of frontal headache. In the pre- and postcontrast CT scans the lesion mimicked an intracranial tumor. At surgery the intraluminal thrombus was partially removed with an ultrasonic surgical aspirator; the decompression allowed the isolation and subsequent temporary dipping of the tracts A1 and A2 of both the anterior cerebral arteries. It was then possible to complete the thrombectomy and to dip the neck of the aneurysm. The report emphasizes the indispensable role of MRI for the accurate diagnosis of giant intracranial aneurysms and the recent improvement of the surgical results concerning this category of aneurysms (mainly related to the present wider availability of technical surgical instrumentation). 相似文献
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Nicoline Treijtel Arjan Barendregt Andreas P Freidig Bas J Blaauboer Jan C H van Eijkeren 《Drug metabolism and disposition》2004,32(8):884-891
An alternative approach is introduced in determining the in vitro intrinsic clearance of slowly metabolized compounds. The longterm sandwich rat hepatocyte culture was exploited, allowing for sufficient substrate depletion to obtain a reliable clearance estimation; in its physiology, it resembles the in vivo liver, thus allowing in vivo extrapolation of the in vitro clearance value. Substrate depletion of tolbutamide and the formation of its metabolites hydroxytolbutamide and carboxytolbutamide were measured in the medium and sandwich layer. Depletion data from the medium were fitted to a mathematical model incorporating system-dependent parameters (diffusion, protein binding, and partitioning) to calculate the hepatocytes' intrinsic clearance. Based on the decrease of the parent compound in the medium, a specific intrinsic clearance value, i.e., clearance per unit of volume of hepatocytes, of 0.085 min(-1) was fitted. This value was in accordance with in vivo and in vitro values from the literature. The model was verified with substrate depletion data from the sandwich layer. Data on metabolite formation showed an incomplete mass balance. A radiochemical experiment revealed the presence of three additional metabolites. These metabolites were analyzed by liquid chromatography-mass spectometry. One was identified as p-tolysulfonylurea. The structure of the other two needs to be elucidated. After the addition of these compounds to the metabolic pattern, the mass balance was completed. The in vitro clearance value was incorporated in a physiologically based pharmacokinetic literature model of tolbutamide that accurately describes the plasma concentration. The approach used in this study successfully predicts the intrinsic clearance of tolbutamide. In addition, the sandwich rat hepatocyte culture also proves to be useful in the identification of metabolic pathways. 相似文献
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Romy A. Doomen Ivana Nedeljkovic Reinder B. Kuitert Cornelis J. Kleverlaan Burcu Aydin 《The Angle orthodontist》2022,92(5):661
ObjectivesTo determine and compare surface characteristics and presence of corrosion in new and used brackets with optical light microscopy (OLM) and scanning electron microscopy (SEM), and with elemental chemical analysis with energy-dispersive X-ray spectroscopy (EDS).Materials and MethodsOLM and SEM were used to analyze 24 new and 24 used conventional premolar brackets. EDS analysis was performed in six used brackets and four new brackets with corrosion-suspected spots.ResultsOLM and SEM images showed wear/abfraction signs, striations, pits/crevices, and adherent material. Used brackets showed more deterioration than new brackets. SEM images disclosed more morphological features than OLM images. EDS analysis revealed a significantly higher phosphorus (P = .001) and sodium (P < .005) weight fraction and significantly lower amounts of chromium (P < .001) in used brackets. The iron, chromium, and nickel weight fractions did not differ significantly between the clean and corrosion-suspected spots. Of the corrosion-suspected spots analyzed by combined SEM and EDS, 44.14% and 6.90% remained corrosion-suspected on used and new brackets, respectively.ConclusionsUsed brackets showed more signs of corrosion than new ones. Combined assessment of SEM and EDS indicates that the bracket surface is affected during orthodontic treatment as a result of corrosion. 相似文献
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Raul Zamora-Ros Valerie Cayssials Mazda Jenab Joseph A. Rothwell Veronika Fedirko Krasimira Aleksandrova Anne Tjønneland Cecilie Kyrø Kim Overvad Marie-Christine Boutron-Ruault Franck Carbonnel Yahya Mahamat-Saleh Rudolf Kaaks Tilman Kühn Heiner Boeing Antonia Trichopoulou Elissavet Valanou Effie Vasilopoulou Giovanna Masala Valeria Pala Salvatore Panico Rosario Tumino Fulvio Ricceri Elisabete Weiderpass Torkjel M. Sandanger Cristina Lasheras Antonio Agudo Maria-Jose Sánchez Pilar Amiano Carmen Navarro Eva Ardanaz Emily Sonestedt Bodil Ohlsson Lena Maria Nilsson Martin Rutegård Bas Bueno-de-Mesquita Kay-Thee Khaw Nicholas J. Wareham Kathryn Bradbury Heinz Freisling Isabelle Romieu Amanda J. Cross Paolo Vineis Augustin Scalbert 《European journal of epidemiology》2018,33(11):1063-1075
Polyphenols may play a chemopreventive role in colorectal cancer (CRC); however, epidemiological evidence supporting a role for intake of individual polyphenol classes, other than flavonoids is insufficient. We evaluated the association between dietary intakes of total and individual classes and subclasses of polyphenols and CRC risk and its main subsites, colon and rectum, within the European Prospective Investigation into Cancer and Nutrition (EPIC) study. The cohort included 476,160 men and women from 10 European countries. During a mean follow-up of 14 years, there were 5991 incident CRC cases, of which 3897 were in the colon and 2094 were in the rectum. Polyphenol intake was estimated using validated centre/country specific dietary questionnaires and the Phenol-Explorer database. In multivariable-adjusted Cox regression models, a doubling in total dietary polyphenol intake was not associated with CRC risk in women (HRlog2?=?1.06, 95% CI 0.99–1.14) or in men (HRlog2?=?0.97, 95% CI 0.90–1.05), respectively. Phenolic acid intake, highly correlated with coffee consumption, was inversely associated with colon cancer in men (HRlog2?=?0.91, 95% CI 0.85–0.97) and positively associated with rectal cancer in women (HRlog2?=?1.10, 95% CI 1.02–1.19); although associations did not exceed the Bonferroni threshold for significance. Intake of other polyphenol classes was not related to colorectal, colon or rectal cancer risks. Our study suggests a possible inverse association between phenolic acid intake and colon cancer risk in men and positive with rectal cancer risk in women. 相似文献
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Dongdong Lu Yu Pi Hao Ye Yujun Wu Yu Bai Shuai Lian Dandan Han Dongjiao Ni Xinhua Zou Jinbiao Zhao Shuai Zhang Bas Kemp Nicoline Soede Junjun Wang 《Nutrients》2022,14(12)
Constipation is a common problem in sows and women during late pregnancy. Dietary fiber has potential in the regulation of intestinal microbiota, thereby promoting intestinal motility and reducing constipation. However, the effects of fibers with different physicochemical properties on intestinal microbe and constipation during late pregnancy have not been fully explored. In this study, a total of 80 sows were randomly allocated to control and one of three dietary fiber treatments from day 85 of gestation to delivery: LIG (lignocellulose), PRS (resistant starch), and KON (konjaku flour). Results showed that the defecation frequency and fecal consistency scores were highest in PRS. PRS and KON significantly increased the level of gut motility regulatory factors, 5-hydroxytryptamine (5-HT), motilin (MTL), and acetylcholinesterase (AChE) in serum. Moreover, PRS and KON promoted the IL-10 level and reduced the TNF-α level in serum. Furthermore, maternal PRS and KON supplementation significantly reduced the number of stillborn piglets. Microbial sequencing analysis showed that PRS and KON increased short-chain fatty acids (SCFAs)-producing genera Bacteroides and Parabacteroides and decreased the abundance of endotoxin-producing bacteria Desulfovibrio and Oscillibacter in feces. Moreover, the relative abundance of Turicibacter and the fecal butyrate concentration in PRS were the highest. Correlation analysis further revealed that the defecation frequency and serum 5-HT were positively correlated with Turicibacter and butyrate. In conclusion, PRS is the best fiber source for promoting gut motility, which was associated with increased levels of 5-HT under specific bacteria Turicibacter and butyrate stimulation, thereby relieving constipation. Our findings provide a reference for dietary fiber selection to improve intestinal motility in late pregnant mothers. 相似文献