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排序方式: 共有3142条查询结果,搜索用时 31 毫秒
21.
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
22.
Elmaci İlhan Altinoz Meric A. Ozlu Burcu Eylem Kahraman Sari Ramazan Er Ozlem Danyeli Ayca Ersen Karaarslan Ercan 《Neurosurgical review》2021,44(1):289-300
Neurosurgical Review - “Benign” metastatic leiomyomas (BML) are indolently growing metastatic tumors which mostly associate with uterine leiomyomas in women in reproductive ages. The... 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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Background: During the last decade, there has been an increased demand for non-metallic materials in orthodontics due to allergies, compatibility with medical imaging devices such as MRI, and aesthetic reasons. Monolithic poly-ether-ether-ketone material could address medical issues such as allergies and MRI compatibility. Moreover, nickel–titanium (NiTi) archwires covered in PEEK, either by a tube or electrophoretic deposition, could address esthetic concerns. This scoping review aims to summarize the available evidence in the literature to provide an overview of the applications and material properties of PEEK in orthodontics. Methods: This scoping review was conducted according to the Joanna Briggs Institute Manual for Evidence Synthesis for scoping reviews and the Preferred Reporting Items for Systematic Review and Meta-Analyses Protocols extension for Scoping Reviews (PRISMA-ScR). We searched for relevant publications in MEDLINE (via PubMed), Embase, Web of Science, Cochrane Library, CENTRAL, ProQuest, and SCOPUS. A gray literature search was conducted on Google Scholar. Results: Six studies were included. In three studies, the authors investigated the feasibility of developing a composite PEEK-NiTi wire, while in two other studies, the authors investigated the feasibility of monolithic PEEK wires. In the final study, the authors investigated the feasibility of PEEK as a bonded retainer. Conclusions: The included studies show promising results in developing monolithic and composite (PEEK-NiTi) materials. Further research on the robustness of PEEK composites in the oral cavity, the status of cytotoxicity and roughness values, and the (bio)-mechanical behavior of the composites is needed. A homogenously set up comparative study of clinically relevant, evenly sized, monolithic PEEK wires versus conventional orthodontic wires for their biomechanical, mechanical, and material properties would clarify the possibilities of developing monolithic PEEK wires. Missing data in the retainer study suggest more research on the mechanical properties and points of failure of PEEK-bonded retainers, and a comparative study comparing the failure and mechanical properties of PEEK-bonded retainers to flat braided metallic bonded retainers is needed. 相似文献
30.
Atike Gken Demiray Aydn Demiray Arzu Yaren Burcu Yapar Takylü Gamze Gkz Dou Serkan Deirmenciolu Umut akrolu Nail
zhan Canan Karan Burin akan Demirel Tolga Doan Melek
zdemir 《The Turkish journal of gastroenterology》2022,33(8):696
Background:First-line treatments for metastatic pancreatic cancer are chemotherapy regimens consisting of 5-fluorouracil or gemcitabine; however, there are no biomarkers to help determine which patients might benefit from which treatment regimens. We aimed to show that microRNAs let-7c and 7d can be used as independent predictive biomarkers for metastatic pancreatic cancer.Methods:A total of 55 patients who had first-line chemotherapy with FOLFIRINOX or gemcitabine + capecitabine were included. Patients were divided into groups based on let-7c and let-7d levels and chemotherapy treatment as let-7c-7d high FOLFIRINOX, let-7c-7d high gemcitabine + capecitabine, let-7c-7d low FOLFIRINOX, and let-7c-7d low gemcitabine + capecitabine. Blood samples were taken from patients before chemotherapy for microRNA let-7c and 7d analysis. MicroRNA isolation was performed using a miRNeasy Serum/Plasma Kit and identified using spectrophotometric measurements. After isolation, microRNA was converted to cDNA using a microRNA cDNA Synthesis Kit with poly (A) polymerase tailing. The expression of microRNA was examined using quantitative real-time polymerase chain reaction.Results:The overall survival of patients who received FOLFIRINOX treatment with a high let-7c-7d level was statistically significantly longer than those who received gemcitabine + capecitabine with a high let-7c-7d level. In addition, patients with low let-7c expression receiving FOLFIRINOX progressed significantly 2.104 times earlier than patients with high let-7c expression receiving FOLFIRINOX.Conclusion:The serum MicroRNA let-7c level was found to be an independent predictive biomarker in the FOLFIRINOX treatment group. 相似文献