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排序方式: 共有5040条查询结果,搜索用时 15 毫秒
41.
K Abbas I A el Toum A M el Hassan 《Oral surgery, oral medicine, and oral pathology》1992,73(5):583-584
Mucosal leishmaniasis as an oral disease in the form of chronic periodontitis with involvement of the oral mucosa is described. Leishmania parasites were isolated from the oral lesions, lymph nodes, and bone marrow. The patient had a low-grade fever and hepatosplenomegaly that regressed along with the oral lesions after treatment with stibogluconate sodium. 相似文献
42.
Amaliya Timmerman MF Abbas F Loos BG Van der Weijden GA Van Winkelhoff AJ Winkel EG Van der Velden U 《Journal of clinical periodontology》2007,34(4):299-304
OBJECTIVE: To study the relationship between vitamin C and the severity of periodontitis. MATERIAL AND METHODS: The study population consisted of subjects from the Malabar/Purbasari tea estate on West Java, Indonesia. In 2002, clinical measurements were performed in 128 subjects, including evaluation of plaque, bleeding on probing, pocket depth and attachment loss. In 2005, 123 out of 128 subjects could be retrieved who were present at the examination of 2002. Blood samples were taken to measure plasma vitamin C levels. Information about the subject's dietary habit was obtained by means of a personal interview guided by a questionnaire. RESULTS: Plasma levels of vitamin C ranged from 0.02 to 34.45 mg/l with a mean of 7.90 mg/l (+/-5.35). The correlation coefficient between plasma vitamin C level and periodontal attachment loss was -0.199 (p<0.05); stepwise linear regression revealed that vitamin C levels explained 3.9% of the variance in periodontal attachment loss. Subjects with vitamin C deficiency (14.7% of the study population) had more attachment loss compared with those with depletion or normal plasma vitamin C values. CONCLUSION: The negative association between plasma vitamin C levels and periodontal attachment loss suggests that vitamin C deficiency may contribute to the severity of periodontal breakdown. 相似文献
43.
Farshid Davoodi Abbas Raisi Asghar Rajabzadeh Mohammad Hassan Hablolvarid Amir Zakian 《Andrologia》2020,52(2):e13479
In this research, the impacts of combined administration of verapamil and heparin on testicular torsion damage were examined. In this experimental study, 30 sexually mature male Wistar albino rats were divided into five equal groups haphazardly (n = 6): Group 1 was the sham group. In group 2, a 2-hr testicular torsion was induced, and thereafter, detorsion was done. Rats in group 3 and group 4 experienced an identical surgical procedure like group 2, but verapamil and heparin were administered in 0.3 mg/kg and 800 IU/kg doses respectively, and in group 5, a combination of verapamil and heparin were administered. Intraperitoneal drug injection in all treatment groups was done 30 min before testicular detorsion. Testicular torsion significantly changed sperm parameters, oxidative stress biomarkers and Cosentino's histological score compared to the sham group (p < .05). All treatment groups reduced testicular damage by decreasing oxidative stress and improving sperm parameters, but heparin and co-administration of verapamil and heparin were significantly better than verapamil injection alone. However, heparin injected group was more effective than other treatment groups (p < .05). Overall, an anticoagulant like heparin is more effective than a calcium channel blocker such as verapamil, and it is more likely to reduce testicular torsion injuries. 相似文献
44.
Faheem Ullah Fatima Javed M. B. H. Othman Abbas Khan Rukhsana Gul Zulkifli Ahmad 《Journal of biomaterials science. Polymer edition》2018,29(4):376-396
Addressing the functional biomaterials as next-generation therapeutics, chitosan and alginic acid were copolymerized in the form of chemically crosslinked interpenetrating networks (IPNs). The native hydrogel was functionalized via carbodiimide (EDC), catalyzed coupling of soft ligand (1,2-Ethylenediamine) and hard ligand (4-aminophenol) to replace –OH groups in alginic acid units for extended hydrogel- interfaces with the aqueous and sparingly soluble drug solutions. The chemical structure, Lower solution critical temperature (LCST ≈ 37.88 °C), particle size (Zh,app ≈ 150–200 nm), grain size (160–360 nm), surface roughness (85–250 nm), conductivity (37–74 mv) and zeta potential (16–32 mv) of native and functionalized hydrogel were investigated by using FT-IR, solid state-13C-NMR, TGA, DSC, FESEM, AFM and dynamic light scattering (DLS) measurements. The effective swelling, drug loading (47–78%) and drug release (53–86%) profiles were adjusted based on selective functionalization of hydrophobic IPNs due to electrostatic complexation and extended interactions of hydrophilic ligands with the aqueous and drug solutions. Drug release from the hydrogel matrices with diffusion coefficient n ≈ 0.7 was established by Non- Fickian diffusion mechanism. In vitro degradation trials of the hydrogel with a 20% loss of wet mass in simulated gastric fluid (SGF) and 38% loss of wet mass in simulated intestinal fluid (SIF), were investigated for 400 h through bulk erosion. Consequently, a slower rate of drug loading and release was observed for native hydrogel, due to stronger H-bonding, interlocking and entanglement within the IPNs, which was finely tuned and extended by the induced hydrophilic and functional ligands. In the light of induced hydrophilicity, such functional hydrogel could be highly attractive for extended release of sparingly soluble drugs. 相似文献
45.
Christina Bergqvist Bilal Abdallah Divina‐Justina Hasbani Ossama Abbas Abdul Ghani Kibbi Lamiaa Hamie Mazen Kurban Nelly Rubeiz 《American journal of medical genetics. Part A》2018,176(3):733-738
46.
Mesenchymal stem cells (MSCs) are a population of multipotent cells with the ability of expansion and plastic-adherence in vitro. MSCs can differentiate into chondrocytes, osteocytes and adipocytes; they lack co-stimulatory molecules and have small amount of MHC-I that makes no immunogenicity. These characteristics are empowering MSCs’ huge in vivo applications. In addition, MSCs possess the ability of regulating the immune responses in many diseases. Many studies have shown that MSCs have immunosuppressive as well as immunoenhancing properties such as inhibition of T-lymphocytes proliferation and cytokines production which lead to the balance of Th1 and Th2. Some other immunomodulatory features of MSCs are increasing suppressive capacity of Treg, reducing activity of B-lymphocytes and immunoglobulins secretion, inhibition of dendritic cells maturation and antigen presenting capacity, and inhibition of NK-cells activity. MSCs also exert inhibitory effects on neutrophil apoptosis and reduce reactive oxygen species production. The purpose of this paper is to focus on the MSCs? effects on immune cells, especially neutrophils. 相似文献
47.
Abolfazl Mollalo Abbas Alimohammadi Mohsen Shahrisvand Mohammad Reza Shirzadi Mohammad Reza Malek 《亚太热带病杂志(英文版)》2014,4(3):176-180
Objective
To investigate the relations between the vegetation cover and occurrence of cutaneous leishmaniasis (CL) in Golestan province during 2010-2012.Methods
Data of monthly CL incidence and remote sensing normalized difference vegetation index (NDVI) of moderate resolution imaging spectroradiometer sensor were used in the study. Pearson''s correlation analysis was conducted to examine the type and strength of relationships between the spatially averaged NDVI variables (i.e. minimum, maximum and mean NDVI values) and CL incidence in township level. Spearman rank correlation was carried out to explain associations between the monthly CL incidence and NDVI variables at 0, 1, 2, 3 and 4 months lagged periods. Locations of CL cases at village level were geocoded and compared with frequency of CL cases in each NDVI-derived vegetation categories.Results
Pearson''s analysis revealed significant associations between the NDVI variables and CL incidence at the township level (P<0.05). Results of Spearman analysis indicated that the highest correlations between NDVI variables and monthly CL incidence were established when the NDVI time-series lagged the CL incidence series NDVI variables. Purely spatial analysis demonstrated that despite majority of cases occurred at partially-vegetated areas, the possibility of CL occurrence was higher in bare soil areas by taking into account area of each vegetation zones.Conclusions
lack or low vegetation cover is a major determinant of CL frequencies in Golestan province. The decrease of the mean vegetation density in townships is accompanied by increase of CL occurrence and vice versa. 相似文献48.
Background
Various conditions lead to the development of colonic fistulas. Contemporary surgical data is scarce and it is unclear whether advances in surgical care have impacted outcome. The aim of the present study was to review the short- and long-term outcome of patients treated surgically for colonic fistula over an 8-year period at a tertiary institution.Methods
A retrospective review was performed, focusing on the type of operative interventions, short- and long-term complications, length of hospital stay, readmission rate, mortality rate, and fistula recurrence.Results
Forty-five patients were treated for colonic fistula. The most common etiology was diverticulitis (74 %). Fistula type was colovesical (58 %), colocutaneous (18 %) and colovaginal (15 %). Laparoscopic resection was performed in 42 % of cases. An intraoperative complication occurred in 4 %. A primary anastomosis was performed in 96 % of patients and 10 (23 %) had a temporary stoma. Median length of hospital stay was 6 days. Postoperative complications were common (47 %) and wound infection was noted in 20 % of patients. The readmission rate was 29 % and the 90-day mortality was 4 %. All patients healed their fistula with no recurrences noted during a median follow-up of 37 months.Conclusions
Surgical intervention healed the majority of patients with colonic fistula. However postoperative complications were common and readmission occurred in one-third of the cases. Laparoscopic excision was feasible in nearly half of the patients. 相似文献49.
Shilpa Trivedi Nand Lal Abbas Ali Mahdi Madhukar Mittal Babita Singh Shivani Pandey 《Journal of periodontology》2014,85(5):713-720
Background: The aim of this study is to investigate the impact of diabetes, a known risk factor for periodontitis, on activities of antioxidant enzymes superoxide dismutase (SOD), glutathione reductase (GR), and catalase (CAT) as well as levels of free radical damage marker malondialdehyde (MDA) in blood and saliva of individuals with chronic periodontitis (CP). Methods: Sixty patients with CP (30 patients with type 2 diabetes mellitus [DMCP] and 30 systemically healthy patients [CP]) and 60 periodontally healthy individuals (30 patients with type 2 diabetes mellitus and 30 systemically healthy patients [PH]) were included in this study. After clinical measurements, blood and saliva samples were collected. SOD, GR, and CAT activities in red blood cell lysate and saliva and MDA levels in plasma and saliva samples were spectrophotometrically assayed. An analysis of variance test followed by a post hoc test was used to compare the intragroup and intergroup variances among the study groups. Results: MDA levels in both the periodontitis groups were higher than in the periodontally healthy groups, but the difference between the CP and DMCP groups did not reach statistical significance (P >0.05). There was a highly significant difference between the CP and PH groups for all the enzymes studied except for SOD in blood. Only salivary SOD and GR activities were significantly different in the CP and DMCP groups. Conclusions: This study favors the role of oxidative stress in both diabetes and periodontitis. It shows that the compensatory mechanism of the body is partially collapsed because of excessive production of free radicals during periodontitis and is not able to cope with increased free radical generation attributable to diabetes, thereby worsening the situation. 相似文献
50.