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71.
Is toombak a risk factor for oral leukoplakia and oral squamous cell carcinoma ? A systematic review
72.
Abdolhalim Rajabi Abbas Rezaianzadeh Abdolreza Rajaeefard Sareh Keshavarzi Kamran B. Lankarani 《The journal of maternal-fetal & neonatal medicine》2016,29(22):3622-3628
Objective: Assessment of the contribution of non-medical factors to mode of delivery and birth preference in Iranian pregnant women in southwestern Iran.Study design: This cohort study used data from a structured questionnaire completed in early pregnancy and information about the subsequent delivery obtained through personal contact. Women were recruited by random sampling from antenatal clinics when scheduling visits over the course of 5 weeks from December 2012 to February 2013 and were followed-up 1 month after birth. Of the 2199 women recruited, 99.63% were eligible for the study.Results: Of the 748 women who expressed a desire to deliver their babies by cesarean section (CS) in early pregnancy, 87% had an elective cesarean section. The logistic regression analyses showed that normative beliefs (odds ratio [OR] 1.792, 95% confidence interval (1) 1.073–2.993), control beliefs (OR: 0.272, 95% CI: 0.162–0.459), and evaluation of outcomes (OR: 0.431, 95% CI: 0.268–0.692) favored the preference for cesarean section. The desire for delivery by elective cesarean section was associated with normative beliefs (OR: 1.138; 95% CI: 1.001–1.294), control beliefs (OR: 0.804; 95% CI: 0.698–0.927), and expectations about maternity care (OR: 0.772; 95% CI: 0.683–0.873), medical influences (OR: 1.150; 95% CI: 1.023–1.291), evaluation of outcome (OR: 0.789; 95% CI: 0.696–0.894), age, preference for cesarean section (OR: 5.445; 95% CI: 3.928–7.546), spouse educational level, and number of live births.Conclusions: A woman’s preference for delivery by cesarean section influenced their subsequent mode of delivery. Asking women in early pregnancy about their preferred mode of delivery provides the opportunity to extend their supports which might reduce the rate of elective cesarean section. This decision is affected by age, spouse educational level, number of live births, and preconceived maternal attitudes about delivery. 相似文献
73.
Because epithelial cells are the major cell type productively infected with Chlamydia during genital tract infections, the overall goal of our research was to understand the contribution of infected epithelial cells to the host defense. We previously showed that Toll-like receptor 3 (TLR3) is the critical pattern recognition receptor in oviduct epithelial (OE) cells that is stimulated during Chlamydia infection, resulting in the synthesis of beta interferon (IFN-β). Here, we present data that implicates TLR3 in the expression of a multitude of other innate-inflammatory immune modulators including interleukin-6 (IL-6), CXCL10, CXCL16, and CCL5. We demonstrate that Chlamydia-induced expression of these cytokines is severely disrupted in TLR3-deficient OE cells, whereas Chlamydia replication in the TLR3-deficient cells is more efficient than in wild-type OE cells. Pretreatment of the TLR3-deficient OE cells with 50 U of IFN-β/ml prior to infection diminished Chlamydia replication and restored the ability of Chlamydia infection to induce IL-6, CXCL10, and CCL5 expression in TLR3-deficient OE cells; however, CXCL16 induction was not restored by IFN-β preincubation. Our findings were corroborated in pathway-focused PCR arrays, which demonstrated a multitude of different inflammatory genes that were defectively regulated during Chlamydia infection of the TLR3-deficient OE cells, and we found that some of these genes were induced only when IFN-β was added prior to infection. Our OE cell data implicate TLR3 as an essential inducer of IFN-β and other inflammatory mediators by epithelial cells during Chlamydia infection and highlight the contribution of TLR3 to the inflammatory cytokine response. 相似文献
74.
Kamran Sardari 《Comparative clinical pathology》2007,16(2):97-102
Local injection of a mixture of beta-aminopropionitril fumarate (BAPN-f) and sodium hyaluronate (NaH+) together with controlled exercise were evaluated for treatment of superficial digital flexor tendon (SDFT) injuries in horses.
Fourteen mixed breed horses with subacute SDF tendon injuries in forelimbs were randomly assigned to two groups. One group
received BAPN-f (0.7 mg/ml) and the other received NaH+ (10 mg/ml) all by intratendinous injection. Controlled exercise started during the first week after intratendinous treatment
and continued for 12 weeks. Cross-sectional area (CSA) of the SDFT, diameter of the SDFT, and relative area of the lesion
(presence of CSA) were measured by ultrasonographic examination. Lesions were semiquantitatively graded for echogenicity on
a scale of 0 to 4. The lesion severity in CSA was significantly reduced by BAPN and NaH compared to those horses treated by
BAPN only (p < 0.05). Lesion echogenicity score was significantly higher in horses treated with BAPN and NaH+ at day 0 compared to horses treated with BAPN (p < 0.05). At the end of the study, lesion echogenicity score was significantly reduced in the horses treated with BAPN and
NaH+ compared to horses treated by BAPN only (p < 0.05). According to the results of the present study, a combination of BAPN-f and NaH+ has a greater beneficial effect on tendon healing and remodeling in horses, as assessed by sonographic examination, compared
to treatment with single drugs. 相似文献
75.
Kamran Sardari Ehsan Galedar Kakhki Mehrdad Mohri 《Comparative clinical pathology》2007,16(3):197-200
Ten bulls (age 7 months, weight 302 ± 15 kg) were used in this study. After sterile preparation of skin, a full thickness
wound (20 × 20 mm) was created in each bull. The bulls were randomly assigned into two groups: group 1 received 6 ml Theranekron
subcutaneously and group 2 penicillin banzatine 10,000 IU/kg IM. These doses were repeated 6 days after initial wounding.
At days 0, 3, 6, 10 and 14, digital photographs were taken from the wounds to calculate wound contraction and epithelialization
using geometry. Chi-square test was performed for statistical analysis using SPSS 9 for Windows. There was no significant
differences in wound contraction between trial groups (P > 0.05) but a statistical difference was seen in epithelialization between groups (P < 0.05). Epithelialization is one of the most important factors in wound healing. According to the results of the present
study, Theranekron can significantly stimulate epithelialization in full thickness wounds in cows during the first 14 days
of healing. 相似文献
76.
Reciprocal activity between populations of neurons has been widely observed in the brain and is essential for neuronal computation. The different mechanisms by which reciprocal neuronal activity is generated remain to be established. A common motif in neuronal circuits is the presence of afferents that provide excitation to one set of principal neurons and, via interneurons, inhibition to a second set of principal neurons. This circuitry can be the substrate for generation of reciprocal signals. Here we demonstrate that this equivalent circuit in the cerebellar cortex enables the reciprocal firing rates of Purkinje cells to be efficiently generated from a common set of mossy fiber inputs. The activity of a mossy fiber is relayed to Purkinje cells positioned immediately above it by excitatory granule cells. The firing rates of these Purkinje cells increase as a linear function of mossy fiber, and thus granule cell, activity. In addition to exciting Purkinje cells positioned immediately above it, the activity of a mossy fiber is relayed to laterally positioned Purkinje cells by a disynaptic granule cell → molecular layer interneuron pathway. Here we show in acutely prepared cerebellar slices that the input-output relationship of these laterally positioned Purkinje cells is linear and reciprocal to the first set. A similar linear input-output relationship between decreases in Purkinje cell firing and strength of stimulation of laterally positioned granule cells was also observed in vivo. Use of interneurons to generate reciprocal firing rates may be a common mechanism by which the brain generates reciprocal signals. 相似文献
77.
Isaac Naggar Sae Uchida Haroon Kamran Jason Lazar Mark Stewart 《The journal of physiological sciences : JPS》2012,62(6):479-492
The sympathetic and parasympathetic divisions of the autonomic nervous system modulate cardiac rhythm and the probability of arrhythmia occurrence. Both increased sympathetic drive and hypoxia increase the likelihood for ventricular fibrillation (VF). Vagus nerve stimulation (VNS) can protect from fatal arrhythmias via cholinergic and nitrergic action. We sought to determine boundary conditions for VF and defibrillation by autonomic manipulations accompanied or not by hypoxic changes in urethane-anesthetized rats. VF was induced with (1) vagotomy, (2) systemic high-dose (>15?mg/kg) isoproterenol, and (3) hypoxemia. When VNS (50?Hz) produced cardiac standstill, it converted every VF episode (59/59). A nitric oxide synthase inhibitor did not reduce VNS efficacy (13/14 episodes converted), but addition of atropine reduced VNS efficacy (11/27 episodes converted). VF can be induced by autonomic derangements only under constrained conditions, including sympathetic over-activation, reduced parasympathetic input, and hypoxemia. VNS can provide an alternative method to defibrillate via its cholinergic action. 相似文献
78.
79.
Zahoor-ul-Hassan Khan MZ Saleemi MK Khan A Javed I Hussain A 《Journal of immunotoxicology》2011,8(3):204-209
This study was designed to evaluate the immunological status of chicks hatched from the ochratoxin A (OTA)-contaminated eggs. For this purpose, 900 fertile White Leghorn (WL) layer breeder eggs were divided into eight groups (A-H). Group A was maintained as untreated control, whereas Group B was kept as sham control (10 μL of 0.1?M NaHCO?). Groups C, D, E, F, G, and H were injected with 0.01, 0.03, 0.05, 0.10, 0.50, and 1.00 μg OTA/egg, respectively. Eggs were incubated at 37.5 °C and 65% relative humidity. Hatched chicks from each group were then maintained separately under standard environmental conditions. At Day 18-of-age, chicks (n?=?10) from each group were used for lymphoblastogenic response against an intradermal administration of phytohemagglutinin P (PHA-P). At Day 30-of-age, abdominal macrophages, collected from 15 chicks in each group, were utilized for determination of phagocytic potential using sheep red blood cells (SRBC) as particulate antigen and for nitrite production in response to lipopolysaccharide. Antibody (Ab) titers (i.e. total antibodies, IgG, and IgM) against SRBC were determined at 7 and 14 days after primary (at Day 13-of-age) and booster (given 14 days after primary) intravenously administered SRBC doses. The lymphoblastogenic responses of the chicks hatched from OTA-contaminated eggs in response to PHA-P administration were significantly lower at 24, 48, and 72 h after PHA-P injection when compared with responses by control chicks. The percentage of abdominal macrophages displaying phagocytosis of SRBC, the number of SRBC/macrophage, and nitrite production were each significantly lower in cells from chicks in the OTA-administered groups. Total Ab, IgG, and IgM titers against SRBC showed significant reductions in the groups that had been hatched from eggs injected with the higher doses of OTA (as compared with titers associated with chicks in control eggs). These findings suggested that there are substantive immunosuppressive risks in chicks that could be exposed to OTA in ovo. 相似文献
80.
Inducible co-stimulator ligand (ICOSL) is a rather newly defined co-stimulatory molecule, which, through interaction with ICOS expressed on T cells, plays an important role in T-cell activation, differentiation and function. T(h)2-type immune responses are critical for the development and maintenance of allergic responses including asthma. Using knockout (KO) mice, we have assessed the role of ICOSL in allergic airway inflammation and responsiveness using a standard mouse asthma model induced by ovalbumin (OVA) sensitization and challenge. Our data show that OVA-treated ICOSL KO mice exhibit significantly less lung eosinophilic infiltration, histopathology, mucus production and virtually no airway hyperresponsiveness in contrast to wild-type (Wt) counterparts. Serum antibody analysis showed that antigen-specific IgG1, IgG2a and IgE titers in ICOSL KO mice were significantly lower than those of Wt controls. Also, CD4(+) T cells isolated from ICOSL KO mice produced less T(h)2 cytokines (IL-4, IL-5, IL-10 and IL-13) but more T(h)1 (IFN-γ) and IL-17 than their Wt controls. Taken together, we conclude that ICOSL plays an important role in predisposing individuals to allergic airway hyperresponsiveness by enhancing IgE antibody class switching and T(h)2 cytokine production and diminishing the T(h)17 response and airway eosinophilia. 相似文献