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1.
Objectives

The study aims to evaluate the effects of non-thermal atmospheric plasma (NTAP) treatments on dentin wetting and surface free energy (SFE) and compare the effects of NTAP treatment, etch-and-rinse, and self-etch protocols for application of universal adhesives.

Materials and methods

Mid-coronal dentin of intact third molars was used to measure contact angles of distilled water, ethylene-glycol, and diiodomethane and calculate SFE following different NTAP preset treatments (feeding gas consisting of pure He, He + 1% O2, He + 1.5% O2), power input (1 or 3 W), and tip-to-surface distance (2, 4, or 8 mm). Contact angles of reference liquids and SFE of dentin following He + 1.5% O2 at 3-W and 4-mm treatment was compared to phosphoric acid etching. Contact angles of Single Bond Universal (SBU; 3M ESPE) and Clearfil Universal Bond (CUB; Kuraray Noritake) were measured following NTAP, etch-and-rinse, and self-etch protocols.

Results

NTAP significantly reduced contact angles of reference liquids and increased dentin SFE compared to untreated dentin (p < 0.05). O2 intensified the effect of He NTAP (p < 0.05). NTAP and phosphoric acid increased dentin polarity and Lewis base surface characteristics. Phosphoric acid increased contact angles of adhesives compared to the self-etch protocol (p < 0.05). NTAP resulted in lower adhesive contact angles than phosphoric acid, the difference being statistically significant for CUB (p < 0.05). Compared to the self-etch protocol, NTAP slightly reduced CUB contact angle but not that of SBU (p > 0.05).

Conclusions

He NTAP with and without O2 increased dentin wetting and SFE, surpassing the effect of phosphoric acid and lowering adhesive contact angles. NTAP produced no apparent micro-morphological changes on dentin surface comparable to acid etching.

Clinical significance

NTAP treatment of dentin prior to adhesive application increases dentin wetting and surface free energy facilitating better adhesive distribution on dentin surface compared to phosphoric acid etching and similar to the “self-etch” application protocol.

  相似文献   
2.
A total of 48 patients with BPH were studied before and after TURP. Initial diagnostic evaluation consisted of clinical examination, IPSS, uroflowmetry, cystometry, and “pressure-flow” study. Contribution of the important urodynamic measurements for the favourable symptomatic outcome was evaluated. There was significantly better result in patients with severe symptoms preoperatively (p=0.03), low preoperative Qmax (p=0.03), and presence of obstruction (p=0.004), especially in patients with normal or strong detrusor contraction. Preoperative volume of residual urine as well as detrusor instability were not important for the symptomatic outcome. IPSS and uroflowmetry should not be treated as optional diagnostic tests. They improved the percentage of patients with an excellent symptomatic outcome from 62.5% to 90% (p=0.04). “Pressure-flow” study is the reliable method for the achievement of excellent symptomatic outcome, but not significantly better than uroflowmetry and IPSS together. “Pressure-flow” study should be performed only in inconclusive preoperative cases.  相似文献   
3.
Summary The activity of glutamate dehydrogenase, the enzyme of glutamate degradation, was measured in platelets of 27 healthy controls and 85 patients with different degenerative cerebellar and/or basal ganglia disorders. A group of 7 patients was selected with slowly progressive multiple-system atrophy, in whom a clinical diagnosis of olivopontocerebellar atrophy appeared tenable, with decreased activity of glutamate dehydrogenase (38% of the mean control value). In 4 patients data on inheritance were compatible with the genetic pattern of autosomal recessive inheritance, while 3 patients were sporadic cases. In an effort to define this group of patients more precisely, it is suggested that decreased activity of glutamate dehydrogenase induces an increase in extracellular glutamate levels in the central nervous system with subsequent development of excitotoxicity.  相似文献   
4.
The effect of subclinical infection with lymphoid leukosis virus (LLV) on the productivity traits of layer hens was investigated. In hens that shed gs-antigen of LLV to albumen, onset of sexual maturity was delayed by a mean of 11 days and the number of eggs laid was reduced -by 68 per hen up to 75 weeks of age. Shedding hens laid on average 2 g lighter eggs and of lesser specific gravity. Thirty-four % less chickens were obtained in the reproduction programmes from LLV-shedders in comparison with non-shedders. LLV had no significant effect on fertility and hatchability. Reduced egg-related performance was only directly related to LLV-shedding and dams' shedding status had no effect on the egg-related performance of their LLV-free progeny. Dams' shedding status, however, correlated with higher mortality (10% higher) among their progeny. The percentage of non-layers was also higher in progeny of LLV-shedders. Meconia were highly suitable samples for identifying both transmitting dams and infected chickens but only if the test for infectious virus was performed. ELISA on meconia was less reliable than the test for virus and therefore is not recommended for the detection of residual of infected chickens in the flocks selected for reduced gs-antigen shedding.  相似文献   
5.
Summary The S1, N and M proteins, obtained from the nephropathogenic N1/62 strain of infectious bronchitis virus (IBV) by immunoaffinity purification with monoclonal antibodies, were used for immunization of chickens. For all three antigens multiple immunizations were necessary for induction of an antibody response. Protection of chickens vaccinated with the S1 glycoprotein against virulent challenge was demonstrated by the complete absence of virus in tracheas and kidneys of vaccinated chickens. Following four immunizations with the S1 glycoprotein 71% and 86% of chickens were protected at the level of tracheas and kidneys, respectively. Three immunizations with the S1 glycoprotein protected 70% and 10% of chickens at the level of kidney and trachea, respectively. Neither the N nor the M antigen induced protection to a virulent challenge with the nephropathogenic N1/62 strain of IBV after four immunizations. Virus neutralizing, haemagglutination inhibiting and ELISA antibodies were detected in chickens immunized with the S1 glycoprotein and inactivated N1/62 virus, however there was no correlation between the presence of any of these antibodies and protection.  相似文献   
6.
Virus particles exposed to specific anti-virus antibodies result in the formation of immune complexes (Icx). Recent vaccination strategies have employed this feature, and an infectious bursal disease virus (IBDV) vaccine based on Icx has been released and is expected to replace conventional IBDV vaccines. We evaluated whether chicken recombinant antibodies (rAb) specific for IBDV, rather than conventional chicken anti-IBDV sera, could be used to generate Icx. Out of 14 rAb expressed as soluble single-chain variable fragments (scFv), nine were able to completely neutralize Bursavac, a live IBDV vaccine, when tested in ovo. When these rAb were mixed with IBDV and inoculated into either 18-day-old embryos, or 1-day-old or 2-week-old specific pathogen free chicks, a rAb.IBDV complex was formed. These Icx were similar to those produced by polyclonal chick anti-IBDV sera and IBDV. Following inoculation of the rAb.IBDV complex, the virus was rendered non-infectious for 5 to 7 days. After this time virus was released from the Icx, resulting in infection of the inoculated chicks and subsequent induction of an immune response and protection against virulent IBDV challenge. The results indicated that genetically derived antibodies can replace polyclonal sera in the formulation of Icx vaccines.  相似文献   
7.
Syndromes of intracranial hemorrhage, and particularly subarachnoidal, i.e., intracerebral hemorrhage (SAH and IH) present clinical entities that are the most severe conditions in neurology. Timely recognition, diagnosis and adequate therapy are imperative. The most important factor that aggravates an already difficult prognosis of those entities is cerebral vasospasm. Upon the presented facts, the aim of this investigation was to establish the value and role of administration of selective calcium channel blocker--nimodipine in patients with SAH and IH compared to the degree of neurological and functional impairment, as well as the recovery of the function of consciousness compared to the patients with those syndromes from an earlier period, who were not treated with this medicament. Investigation comprised 30 patients who received nimodipine and 20 patients without this agent in therapeutic program. Results of the investigation confirmed significant difference concerning the neurological recovery, improvement of functional capability and recovery or consciousness disturbances, respectively, in patients who received nimodipine compared to the group without this agent. It can be concluded that nimodipine as calcium channel blocker with multitopic pharmacological effects on mechanism of SAH or IH development, respectively, as well as on the development of complications of those syndromes, particularly to the development of vasospasm and reactive ischemia, with the improvement of hemorrheologic disorders deserves to be included as the unavoidable segment of therapeutic program of SAH and IH syndrome immediately after clinical phenomenology is revealed.  相似文献   
8.
In Belgrade Military Medical Academy 88 males and 1 female (aged 13-55, average 28.6 years) with war craniocerebral injuries (CCI) were secondarily neurosurgically treated from October 1991 trough December 1992. Primary neurosurgical management of these patients was performed in war hospitals in former Yugoslavia. Out of 89 patients, 78 had penetrating, and 11 closed CCI. Out of 55 patients with penetrating CCI who underwent surgery, intracranial debridement was performed in 34 patients. All patients with severe CCI (GCS = 3-8) were severely by disabled or died, and in the majority of patients with minor CCI (GCS = 13-15) the outcome was good (p < 0.01). Statistical analysis showed no significant correlation between the extent of cerebral lesion and the outcome of penetrating CCI (p > 0.05). Eight (10.3%) patients with penetrating CCI died. The outcome of war CCI mostly depended on the severity of injury.  相似文献   
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