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71.
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Plants with antidiabetic activities provide important sources for the development of new drugs in the treatment of diabetes mellitus. In the present study, we investigated possible antihyperglycemic and antioxidative activities of the aerial part of the Matricaria chamomilla L. ethanolic extract (MCE) in streptozotocin (STZ; 70 mg/kg, i.p.)-induced diabetic rats. The following groups were assigned; sham (did not receive any substance), STZ + distilled water (control), STZ + 5 mg/kg glibenclamide, STZ + 20 mg/kg MCE, STZ + 50 mg/kg MCE, STZ + 100 mg/kg MCE. Diabetic rats were treated for 14 days by gavage. Postprandial blood glucose levels, malondialdehyde, reduced glutathione (GSH), nitrate, nitrite, ascorbic acid, retinol, β-carotene, superoxide dismutase, and catalase levels were measured, and immunohistochemical studies were performed in all of the groups. The obtained data showed that STZ resulted in oxidative stress and affected the antioxidant status. Treatment with different doses of MCE significantly reduced postprandial hyperglycemia and oxidative stress, and augmented the antioxidant system. In histological investigations, MCE treatment protected the majority of the pancreatic islet cells, with respect to the control group. As a result, MCE exhibited significant antihyperglycemic effect and protected β-cells in STZ-diabetic rats, in a dose-dependent manner, and diminished the hyperglycemia-related oxidative stress.  相似文献   
73.
G-protein coupled receptor kinase 2 (GRK2) regulates the activity of many receptors. Because potent inhibitors of GRK2 are thus far limited to polyanionic compounds like heparin, we searched for new inhibitors with the aid of a molecular model of GRK2. We used the available crystal structure of cAMP dependent protein kinase (cAPK) as a template to construct a 3D homology model of GRK2. Known cAPK and GRK2 inhibitors were docked into the active sites of GRK2 and cAPK using DOCK v3.5. H8 docked into the hydrophobic pocket of the adenosine 5-triphosphate (ATP) binding site of cAPK, consistent with its known competitive cAPK inhibition relative to ATP. Similarly, 3 of 4 known GRK2 inhibitors docked into the ATP binding pocket of GRK2 with good scores. Screening the Fine Chemicals Directory (FCD, containing the 3D structures of 13,000 compounds) for docking into the active sites of GRK2 identified H8 and the known GRK2 inhibitor trifluoperazine as candidates. Whereas H8 indeed inhibited light-dependent phosphorylation of rhodopsin by GRK2, but with low potency, 3 additional FCD compounds with promising GRK2 scores failed to inhibit GRK2. This result demonstrates limitations of the GRK2 model in predicting activity among diverse chemical structures. Docking suramin, an inhibitor of protein kinase C (not present in FCD) yielded a good fit into the ATP binding site of GRK2 over cAPK. Suramin did inhibit GRK2 with IC50 32 μM (pA2 6.39 for competitive inhibition of ATP). Suramin congeners with fewer sulfonic acid residues (NF062, NF503 [IC50 14 μM]) or representing half of the suramin molecule (NF520) also inhibited GRK2 as predicted by docking. In conclusion, suramin and analogues are lead compounds in the development of more potent and selective inhibitors of GRK2.  相似文献   
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ObjectivesAlthough endoscopic management is considered as the first-line treatment for biliary strictures, it may be challenging in living donor liver transplant recipients due to the complex nature of duct-to-duct reconstruction. In this study we present the use of a pigtail drainage catheter as a biliary stent to treat biliary strictures after a living donor liver transplant.MethodsTwenty-seven patients with biliary strictures were treated with our novel technique. In this technique, a pigtail catheter was trimmed into 3 parts (proximal, middle, and distal portions). A suture string was passed through the distal hole of the middle portion, which was then reversed and used as a stent while the proximal portion was used as a pusher. Following balloon dilation of the stenotic segment, the distal, reversed middle, and proximal portions were loaded over the guidewire. After proper placement of the stent, the retractor suture string, pusher, and guidewire were removed. The stent was removed during the third or fourth month of placement through endoscopic retrograde cholangiopancreatography (ERCP) in all patients.ResultsNo significant complications developed during the procedure or follow-up period. Ten patients required re-stenting by ERCP during the same session. The mean follow-up period was 2 years. Cholestase enzymes and bilirubin levels were within normal limits in all patients during follow-up.ConclusionStents derived from drainage catheter facilitate treatment of biliary strictures in patients not eligible for the retrograde approach. This stent is cheap, easy to implement, can be easily removed by ERCP, and re-stenting can be applicable in retrograde if needed.  相似文献   
76.
We present the treatment course of a 29-year-old male patient with for a Type 3 FDP avulsion (Jersey's finger) of a fifth finger treated with umbrella handle technique. The patient had a volar base fracture of distal phalanx with dorsal subluxation of DIP joint after a fall. Following open reduction of the FDP avulsion fracture and fixation was achieved with a 0.9 mm one edge hooked Kirschner wire under fluoroscopy control. The straight edge of the wire was driven out in a central position in sterile nail matrix just distal to lunula. The wire was removed at the fifth week when the complete union of the fracture was observed. The patient achieved full flexion in DIP joint without an extension lag.  相似文献   
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78.
Aim: Vitamin A deficiency (VAD), especially in its subclinical form, is a world health problem in young children. The aim of this study was to determine the prevalence of VAD among preschool children in various socio‐economic groups in ?zmir, Turkey. Methods: One hundred and one children aged 24–59 months were selected for the study with cluster sampling method. A questionnaire was completed by the parents, and the dietary pattern was assessed by using a 3‐day dietary record method. Results: Mean serum retinol concentration of the children was 28.3 ± 10.2 μg/dL. Serum vitamin A concentration of two children (2%) was below 10 μg/dL (VAD), whereas 18 (18%) children had vitamin A concentrations between 10 and 20 μg/dL (subclinical deficiency). We did not find any relationship between mean serum retinol concentrations and the independent variables such as socio‐economical levels, age groups, birth weight and gestational age. However, there was a statistically significant positive correlation between serum retinol concentrations and weight‐for‐age and weight‐for‐height Z scores of the children (p < 0.05). Conclusion: Because one‐fifth of the children under 5 years have VAD in ?zmir, Turkey, nutrition education must be given to the families during well‐child care visits, and routine vitamin supplementation should be considered especially in children with malnutrition.  相似文献   
79.
CONCLUSIONS: King penguins have a venous structure in the form of a corpus cavernosum (CC) in their middle ear (ME) submucosa. The CC may be viewed as a special organelle that can change ME volume for pressure equilibration during deep-sea diving it is a pressure regulating organelle (PRO). A similar CC and muscles also surround the external ear (EE) and may constrict it, isolating the tympanic membrane from the outside. A CC was previously found also in the ME of marine diving mammals and can be expected to exist in other deep diving animals, such as marine turtles. OBJECTIVES: Marine animals require equalization of middle ear (ME) pressure when diving hundreds or thousands of meters to catch prey. We investigated what mechanism enables king penguins to protect their ME when they dive to great depths. MATERIALS AND METHODS: Biopsies and serial sections of the ME and the EE of the deep diving king penguin (Aptenodytes patagonicus) were examined microscopically. RESULTS: It was demonstrated that the penguin ME has an extensive network of small and large submucosal venous sinuses. This venous formation, a corpus cavernosum, can expand and potentially 'flood' the ME almost completely on diving, thus elevating ME pressure and reducing the ME space. The EE has a similar protective mechanism.  相似文献   
80.

Introduction  

Patients with history of gestational diabetes (GDM) are at high risk for developing diabetes mellitus (DM) after pregnancy. This study investigates the rate of GDM patients who received screening and the prevalence of DM in the early post-partum period.  相似文献   
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