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21.
Abstract

Serial magnetic resonance (MR) imaging has not yet been validated in the therapy of experimental intracerebral hematomas in a rat model. It is possible to test the effect of local fibrinolysis and aspiration on the clot volume using serial magnetic resonance imaging and different MR-sequences. Experiments were carried out in 22 male Sprague-Dawley rats. Intracerepra I hematoma was produced by injection of fresh autologous blood into the caudate nucleus using a double injection technique. Thirty minutes later 70 rats were treated by injecting 12 µl of recombinant tissue plasminogen activator. MR-imaging was performed immediately after generation of the hematoma and after clot lysis. The clot volume measured in the magnetic resonance images was compared with that obtained in stained histological serial sections at the end of the experiment. Serial MR scanning demonstrated a significant reduction (p<0.07) of hematoma volume after fibrinolysis followed by aspiration of the blood clot. The best correlation between MR- and histological volumetry was found on RF-spoiled FLASH 2D-images. This study documents the efficacy of MRI in detecting and delineating the size of acute intracerebral hematomas and its time course. Local fibrinolysis and aspiration can be simulated in an experimental rat model. [Neural Res 1998; 20: 349-352]  相似文献   
22.
We performed this dosimetric study to compare a nonstandard volumetric modulated arc therapy (VMAT) and helical tomotherapy (HT) techniques with high-dose rate (HDR) brachytherapy (BRT) plan of vaginal vault in patients with postoperative endometrial cancer (EC). Twelve postoperative patients with early stage EC were included in this study. Three plans were performed for each patient; dosimetric and radiobiological comparisons were made using dose-volume histograms and equivalent dose for determining the planning target volume (PTV) coverages in brachytherapy and external beam radiotherapy, and organs-at-risk (OARs) doses between three different delivery techniques. All the plans achieved adequate dose coverage for PTV; however, the VMAT plan yielded better dose conformity, and the HT plan showed better homogeneity for target volume. With respect to the OARs, the bladder D2cc was significantly lower in the BRT plan than in the VMAT and HT plans, with the highest bladder D2cc value being observed in the HT plan. However, no difference was observed in the rectum D2cc of the three plans. Other major advantages of the BRT plan over the VMAT and HT plans were the relatively lower body integral doses and femoral head doses as well as the fact that the integral doses were significantly lower in the BRT plan than in the VMAT and HT plans. This is the first dosimetric comparison of vaginal vault treatment for EC with BRT, VMAT, and HT plans. Our analyses showed the feasibility of stereotactic body radiotherapy technique as an alternative to HDR-BRT for postoperative management of EC patients.  相似文献   
23.
PURPOSE: The purpose of this study was to evaluate the efficacy of three desensitizing agents vs. placebo. MATERIALS AND METHODS: One hundred and six hypersensitive teeth of 26 patients were included in this study, and the baseline hypersensitivity level of all teeth was established as 'moderate' by using Visual Analogue Scale (VAS). The teeth were divided into four groups: to the first group 5% potassium nitrate bio-adhesive gel, to the second 2% sodium fluoride bio-adhesive gel and to the third one step adhesive system Prompt L-Pop were applied as desensitizing agents. Group 4 was the control group in which a desensitizer-free bio-adhesive gel was used as placebo. Post treatment and eighth week control measurements were recorded on VAS. RESULTS: It was observed that the efficacy of three desensitizing agents did not differ from each other (P >0.05) and except for placebo all reduced moderate dentin hypersensitivity effectively (P <0.05). Clinical relevance: Five per cent potassium nitrate, 2% sodium fluoride bio-adhesive gels and one-step bonding agent Prompt L-Pop were effective in reducing moderate dentine hypersensitivity.  相似文献   
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26.
BACKGROUND AND AIMS: Non-response to interferon (IFN) monotherapy is a major therapeutic problem in the management of chronic hepatitis B infection. The efficacy of combination therapy to enhance the immunomodulatory effect of IFN by combining granulocyte-macrophage colony-stimulating factor (GMCSF) or decreasing viral load by adding an antiviral agent such as lamivudine was evaluated prospectively. METHODS: Twenty-four patients with chronic hepatitis B who were non-responders to previous IFN therapy were randomized to receive an IFN and GMCSF (group A, n = 10) or IFN and lamivudine (group B, n = 14) combination for 6 months. The end-of-treatment response was assessed by hepatitis B virus (HBV)-DNA and hepatitis B e antigen (HBeAg) determination. RESULTS: All patients successfully completed both the treatment schedules. The mean age, alanine aminotransferase (ALT) levels, liver histology, HBV-DNA levels and distribution of HBV genotypes were comparable between the two groups. At the end of treatment there was a significant decrease in mean ALT levels. The HBV-DNA and HBeAg loss was seen in six of 10 (60%) patients in group A and in seven of 14 (50%) patients in group B. During a mean follow-up of 15 +/- 3 months, two of six (33%) patients in group A and three of seven (43%) patients in group B relapsed with HBV-DNA and HBeAg positivity, which meant an overall sustained response of 40% and 28%, respectively. None of the factors such as HBV viral load, ALT levels or liver histology could predict the non-response to combination therapy or occurrence of relapse. There was a trend in patients with genotype A compared with genotype D towards non-response to therapy, although the difference was not significant. CONCLUSIONS: The combination of IFN plus GMCSF or lamivudine was effective in non-responders to IFN monotherapy. Larger studies using such combination therapies would be helpful in improving treatment strategies for chronic hepatitis B.  相似文献   
27.
Abstract

Background: To investigate the protective efficacy of pentoxifylline through biochemical parameters and histopathological scores in a caerulein- and alcohol-induced experimental model of chronic pancreatitis in rats.

Methods: A model of chronic pancreatitis with caerulein and alcohol was created in female rats of the genus Sprague Dawley. Pentoxifylline was administered in doses of 25?mg/kg (low dose) and 50?mg/kg (high dose) as a protective agent. Each group contained 8 animals. The groups were: group 1 (control group); caerulein?+?alcohol, group 2 (low-dose pentoxifylline group); caerulein?+?alcohol?+?pentoxifylline 25?mg/kg, group 3 (high-dose pentoxifylline group); caerulein?+?alcohol?+?pentoxifylline 50?mg/kg, group 4 (placebo); caerulein?+?alcohol?+?saline, group 5 (sham group); only saline injection.Rats were sacrificed 12?h after the last injection, and TNF-α, TGF-β, MDA, and GPx concentrations were measured in blood samples. The histopathologic examination was conducted by a pathologist who was unaware of the groups.

Results: The biochemical results of the treatment groups (group 2 and group 3) were statistically significantly lower compared with the control group (group 1) (p?<?.05). The difference between the low-dose treatment group (group 2) and high-dose treatment group (group 3) was significant in terms of biochemical parameters (p?<?.05). The difference between group 2 and the control group was not significant in terms of histopathologic scores (p?>?.05), whereas the difference between the group 3 and the control group was statistically significant (p?<?.05).

Conclusions: As a result, pentoxifylline, which has anti-inflammatory and antioxidant properties, was shown to have protective efficacy in an experimentally generated model of chronic pancreatitis.  相似文献   
28.
Ebastine, is an antihistamine drug that exerts its effect upon oral administration in humans for the treatment of allergic contact dermatitis (ACD), it also has some systemic side effects like gastric distress, headache, drowsiness, and epistaxis. Moreover, topical corticosteroids are used for treatment of ACD, which causes the human skin to lose its thickness and elasticity. Hence, ebastine-loaded solid lipid nanoparticles (E-SLNs) were prepared and their topical efficacy against allergic contact dermatitis was determined. Compritol 888 ATO and tween 80 were used to prepare E-SLNs by cold dilution of the hot micro-emulsion. E-SLNs were optimized statistically by employing a central composite design using Design-Expert® version 11.0. Optimized E-SLNs showed spherical surface morphology, zeta potential of −15.6 ± 2.4 mV, PDI of 0.256 ± 0.03, and particle sizes of 155.2 ± 1.5 nm and th eentrapment efficiency of ebastine was more than 78%. Nanoparticles were characterized using FT-IR, XRD, and TEM. An E-SLNs loaded hydrogel was prepared using chitosan as a gelling agent and glutaraldehyde as a crosslinker. In vitro drug release studies performed for 24 hours on the E-SLNs dispersion and E-SLNs loaded hydrogel showed a sustained release of maximum 82.9% and 73.7% respectively. In vivo studies were conducted on BALB/c mice to evaluate the topical efficacy of the E-SLNs loaded hydrogel for allergic contact dermatitis. ACD was induced on the ear using picryl chloride solution. After induction, ears were treated daily with the E-SLNs loaded hydrogel for 15 days. Swelling behavior, mast cell count, and histopathological studies of the ear confirmed that the hydrogel alleviated the symptoms of allergic contact dermatitis.

Ebastine exerts its effect upon oral administration in humans for the treatment of allergic contact dermatitis (ACD), but it has some systemic side effects. Hence, ebastine-SLNs loaded hydrogel was prepared to increase topical efficacy of ebastine.  相似文献   
29.
Abstract

Background: Tongue-related complications can be seen in suspension laryngoscopy (SL) procedures.

Aims/objectives: This study aimed to detect tongue edema associated with the pressure exerted by a rigid direct laryngoscope by measuring the tongue area using ultrasonography (USG) in patients undergoing SL procedures.

Material and methods: The study group included 31 patients and the control group consisted of 33 patients. Submental USG examinations of the tongue in the coronal plane were performed. In the study and control groups, the first examination (TA1) was done immediately after intubation and the second examination (TA2) was done after the surgery procedure but before extubation. The USG results regarding tongue area for both the groups were compared.

Results: The study and control groups significantly differed in terms of the postoperative tongue area measurements (TA2), as well as tongue edema (based on the TA2???TA1) values.

Conclusions and significance: Direct rigid laryngoscopes may cause tongue edema in SL procedures which was demonstrated by the USG. This tongue edema can be a result of ischemia–reperfusion injury in the tongue due to the pressure exerted by a direct rigid laryngoscope. This study is the first to demonstrate the possible role of USG examination in determining the side effects of SL procedures on the tongue.

Trial Registration ClinicalTrials.gov Identifier: NCT04205253  相似文献   
30.
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