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1.
The aim of this study was to determine the frequency and relationship between disk position and degenerative bone changes in the temporomandibular joints (TMJ), in subjects with internal derangement (ID). MRI and CT scans of 180 subjects with temporomandibular disorders (TMD) were studied. Different image parameters or characteristics were observed, such as disk position, joint effusion, condyle movement, degenerative bone changes (flattened, cortical erosions and irregularities), osteophytes, subchondral cysts and idiopathic condyle resorption. The present study concluded that there is a significant association between disk displacement without reduction and degenerative bone changes in patients with TMD. The study also found a high probability of degenerative bone changes when disk displacement without reduction is present. No association was found between TMD and condyle range of motion, joint effusion and/or degenerative bone changes. The following were the most frequent morphological changes observed: flattening of the anterior surface of the condyle; followed by erosions and irregularities of the joint surfaces; flattening of the articular surface of the temporal eminence, subchondral cysts, osteophytes; and idiopathic condyle resorption, in decreasing order.  相似文献   
2.
STATEMENT OF PROBLEM: Numerous self-etching bonding systems exist, with composition differing from one product to another. It is important for the clinician to know if they are all equally effective, and whether they provide an effective seal between dentin and restorative materials. PURPOSE: This study was designed to measure the hydraulic conductance of physiologic saline across dentin after application of various self-etching bonding systems or of a 1-bottle adhesive system preceded by a phosphoric acid etch. MATERIAL AND METHODS: One hundred extracted noncarious human third molars from patients 18-25 years old were used for this study. Dentin disks were cut from crown segments parallel to the occlusal surface at the top of the pulp cavity. The 100 disks, each 1 mm thick, were divided into 10 groups (n=10 per group), each of which was treated with 1 of 9 self-etching systems-AdheSE, Adper Prompt L-Pop, Clearfil SE Bond, Etch & Prime 3.0, Prime & Bond NRC Nt, One-Up Bond F, optiBond solo Plus Self Etch, Prompt L-Pop, or Xeno III-or a control bonding system (Prime & Bond NT) preceded by a phosphoric acid etch. Hydraulic conductance, the volume of fluid transported across a known area of surface (0.28 cm2) per unit time under a unit pressure gradient (200 cm H2O), was analyzed for the adhesive systems using a fluid flow apparatus (Flodec). First, both sides of each specimen were etched with 36% phosphoric acid for 30 seconds, and the hydraulic conductance was measured every 30 seconds for 15 minutes. The initial set of measurements served as the reference value for each specimen. The measurements were repeated when a smear layer had been formed and, finally, after 1 of the 10 bonding systems had been applied. The data were analyzed using a 1-way ANOVA and Duncan's multiple range test (alpha=.05). RESULTS: The control 1-bottle adhesive used with a phosphoric acid pre-etch did not provide the largest reduction in penetration (42.3%). The greatest mean reduction (68.9%, P<.05) was observed with the self-etching product Xeno III. The mean reduction for the other materials tested were: One-Up Bond F, 60.5%; AdheSE, 58.2%; Etch & Prime 3.0, 56.8%; Adper Prompt L-Pop, 51%; optiBond solo Plus Self Etch, 45%; Clearfil SE Bond, 35.5%, Prime & Bond NRC Nt, 16.4%; and Prompt L-Pop, 16.3%. CONCLUSION: Within the limitations of this study, the self-etching systems tested produced different reductions in dentin permeability. For some, the reduction was much greater than the decrease in dentin permeability provided by the bonding system with a phosphoric acid pre-etch; for others, the reduction was small.  相似文献   
3.
The objectives of this historical-social study are: to describe the circumstances that determined the participation of North American nurses in the formation of the Brazilian nurse; and analyse the process of implementing institutional rituals as a strategy of symbolic fight, to confer visibility to the nurse profession and discuss the symbolic effects of institutional rituals for the consecration of a nurse model for Brazilian society at the time. The primary sources are constituted of pertaining written and photographic documents relative to the studied theme. By reading the documentary corpus an analysis was made of the symbols that had distinguished and established the hierarchies of the actions, as well as the strategies undertaken for the North American nurses, towards implementing a new model of nurses in Brazilian society, coherent with the model of the North American schools of nursing. Institutional rituals, conducted or testified by prestigious figures of the history of Brazil and nursing, were fundamental for the construction of professional identity.  相似文献   
4.
5.

OBJECTIVE:

to estimate survival, mortality and cause of death among users or not of hydroxyurea with sickle cell disease.

METHOD:

cohort study with retrospective data collection, from 1980 to 2010 of patients receiving inpatient treatment in two Brazilian public hospitals. The survival probability was determined using the Kaplan-Meier estimator, survival calculations (SPSS version 10.0), comparison between survival curves, using the log rank method. The level of significance was p=0.05.

RESULTS:

of 63 patients, 87% had sickle cell anemia, with 39 using hydroxyurea, with a mean time of use of the drug of 20.0±10.0 years and a mean dose of 17.37±5.4 to 20.94±7.2 mg/kg/day, raising the fetal hemoglobin. In the comparison between those using hydroxyurea and those not, the survival curve was greater among the users (p=0.014). A total of 10 deaths occurred, with a mean age of 28.1 years old, and with Acute Respiratory Failure as the main cause.

CONCLUSION:

the survival curve is greater among the users of hydroxyurea. The results indicate the importance of the nurse incorporating therapeutic advances of hydroxyurea in her care actions.  相似文献   
6.
This study evaluated the effects of the isolated use of a low dose of methyltestosterone (MT) on cardiovascular reflexes and hormonal levels and its geno‐ and cytotoxic safety in ovariectomized rats. Female Wistar rats were divided into four groups (n = 6), respectively: SHAM (received vehicle methylcellulose 0.5%), SHAM + MT (received MT 0.05 mg/kg), OVX (received vehicle), and OVX + MT (received MT). Twenty‐one days after ovariectomy, treatment was given orally daily for 28 days. The Bezold–Jarisch reflex (BJR) was analyzed by measuring the bradycardic and hypotensive responses elicited by phenylbiguanide (PBG) administration. The baroreflex sensitivity (BRS) was evaluated by phenylephrine and sodium nitroprussite. Myocyte hypertrophy was determined by morphometric analysis of H&E stained slides. Biochemical data were analyzed, as well as micronucleus assay. MT improved BRS and increased testosterone values, but did not change estradiol in the OVX group. MT did not promote changes in mean arterial pressure, heart rate, BJR, serum concentrations of troponin I, weight and histopathology of the heart. MT was able to restore the BRS in OVX rats. The geno‐ and cytotoxic safety of the MT was demonstrated by the absence of an increase in the micronucleus (PCEMN) or change in the ratio between normochromatic erythrocytes and polychromatic erythrocytes (NCE/PCE).  相似文献   
7.
BackgroundPatients with acute myocardial infarction may have a large infarcted area and ventricular dysfunction despite early thrombolysis and revascularization.ObjectiveTo investigate the behavior of circulating cytokines in patients with ST-segment elevation myocardial infarction (STEMI) and their relationship with ventricular function.MethodsIn the BATTLE-AMI (B and T Types of Lymphocytes Evaluation in Acute Myocardial Infarction) trial, patients with STEMI were treated with a pharmacoinvasive strategy. The plasma levels of cytokines (IL-1 β , IL-4, IL-6, IL-10, and IL-18) were tested using enzyme-linked immunosorbent assay (ELISA) at baseline and after 30 days. Infarcted mass and left ventricular ejection fraction (LVEF) were examined by 3-T cardiac magnetic resonance imaging. All p-values < 0.05 were considered statistically significant.ResultsCompared to baseline, lower levels were detected for IL-1 β (p = 0.028) and IL-18 (p < 0.0001) 30 days after STEMI, whereas higher levels were observed for IL-4 (p = 0.001) and IL-10 (p < 0.0001) at that time point. Conversely, no changes were detected for IL-6 levels (p = 0.63). The levels of high-sensitivity C-reactive protein and IL-6 correlated at baseline (rho = 0.45, p < 0.0001) and 30 days after STEMI (rho = 0.29, p = 0.009). At baseline, correlation between IL-6 levels and LVEF was also observed (rho = -0.50, p = 0.004).ConclusionsDuring the first month post-MI, we observed a marked improvement in the balance of pro- and anti-inflammatory cytokines, except for IL-6. These findings suggest residual inflammatory risk. (Arq Bras Cardiol. 2020; [online].ahead print, PP.0-0)  相似文献   
8.
In this study, parathyroid hormone (PTH) receptor binding was examined in the membrane fraction of the endometrium of the shell gland of laying and nonlaying hens by the use of (125)I-PTH-related peptide (PTHrP) binding assays. Specific (125)I-PTHrP binding was found in the endometrium of the shell gland and increased during the first 1 h of incubation and then reached a plateau. Specific (125)I-PTHrP binding increased in line with an increase in protein concentration from 10 to 80 microg. The membrane fraction had specific binding to (125)I-PTHrP. The Scatchard plot analysis revealed a linear profile that indicated the presence of one type of receptor. The equilibrium dissociation constant (K(d)) and the maximum binding capacity (B(max)) in the shell gland decreased 19 h before oviposition in egg-laying hens and remained low for about 20 h during the period of calcification. In contrast, the K(d) and the B(max) in nonlaying hens were constant throughout a 24-h period. These results suggest that PTH acts on the endometrium of the shell gland during the eggshell calcification.  相似文献   
9.
Higher homocysteine (Hcy) levels are associated with cardiovascular risk. The aim of the present study was to evaluate the effect of simvastatin treatment on circulating Hcy levels in obese women without hypertension, diabetes or dyslipidaemia; and to determine whether the 677C>T polymorphism located in methylenetetrahydrofolate reductase (NAD(P)H) (MTHFR) gene modulates the effects of this treatment on Hcy and nitrite (as a biomarker of nitric oxide (NO) bioavailability). Twenty‐five obese women (body mass index ≥ 30 kg/m2) who had received 20 mg/day simvastatin for 6 weeks were enrolled in the study. Venous blood samples were collected to measure plasma biomarkers and gene polymorphisms. Simvastatin treatment significantly reduced total cholesterol, low‐density lipoprotein–cholesterol, thiobarbituric acid‐reactive substances, high‐sensitivity C‐reactive protein and Hcy, whereas nitrite levels were increased. The reduction in Hcy levels in carriers of the T allele was ?20.3% compared with –9.4% in patients with the CC genotype. Importantly, before treatment, nitrite levels were significantly higher in patients with the CC genotype compared with T allele carriers, whereas after treatment these levels were similar between groups. Our findings demonstrate that obese women without comorbidities and carrying the T variant of the 677C>T polymorphism of MTHFR exhibit benefits with simvastatin treatment, mainly in terms of increased NO levels.  相似文献   
10.
The efficient induction of cardiomyocyte differentiation from embryonic stem (ES) cells is crucial for cardiac regenerative medicine. Although Wnts play important roles in cardiac development, complex questions remain as to when, how and what types of Wnts are involved in cardiogenesis. We found that Wnt2 was strongly up-regulated during cardiomyocyte differentiation from ES cells. Therefore, we investigated when and how Wnt2 acts in cardiogenesis during ES cell differentiation. Wnt2 was strongly expressed in the early developing murine heart. We applied this embryonic Wnt2 expression pattern to ES cell differentiation, to elucidate Wnt2 function in cardiomyocyte differentiation. Wnt2 knockdown revealed that intrinsic Wnt2 was essential for efficient cardiomyocyte differentiation from ES cells. Moreover, exogenous Wnt2 increased cardiomyocyte differentiation from ES cells. Interestingly, the effects on cardiogenesis of intrinsic Wnt2 knockdown and exogenous Wnt2 addition were temporally restricted. During cardiomyocyte differentiation from ES cells, Wnt2 didn't activate canonical Wnt pathway but utilizes JNK/AP-1 pathway which is required for cardiomyocyte differentiation from ES cells. Therefore we conclude that Wnt2 plays strong positive stage-specific role in cardiogenesis through non-canonical Wnt pathway in murine ES cells.  相似文献   
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