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971.
We describe the successful use of a combination of nonsurgical root canal treatment and ultrasonic irrigation for collaborative management of a maxillary left lateral incisor with perforation of the apical third of the root. During the endodontic treatment procedure, the ultrasonically activated tip was used for intracanal irrigation. The area of perforation in the apical third of the root and the main root canal space were obturated with gutta-percha and root canal sealer, using a lateral condensation method. A follow-up clinical and radiographic examination at 5 years after treatment showed an asymptomatic tooth with excellent osseous healing.  相似文献   
972.
We examined the abrasiveness of glycine powders with particle diameters of 63 and 100 μm by measuring the depth and volume of defects produced during air polishing of human dentin. A total of 36 extracted human teeth were embedded in acrylic resin. The resin blocks were polished until the dentin surfaces were exposed. The nozzle of an air polisher was mounted 4 mm from the dentin surface, and the dentin surface was treated for 5 s at one of two angles of incidence (45° or 90°). Three materials were used in the polishing process: NaHCO3 powder with a mean particle diameter of 100 μm (Handy Jet Powder), glycine powder with a mean particle diameter of 63 μm (Handy Jet Powder PMTC), and glycine powder with a mean particle diameter of 100 μm (Handy Jet Powder Recall). The defect depth at both angles was significantly deeper after treatment with Handy Jet Powder or Handy Jet Powder PMTC. The defect volume was the greatest with Handy Jet Powder, followed by Handy Jet Powder PMTC, and Handy Jet Powder Recall. The larger diameter glycine powder resulted in less damage to the dentin.  相似文献   
973.
The combined efficacy of a long-lasting insecticidal net (LLIN) and a carbamate-treated plastic sheeting (CTPS) or indoor residual spraying (IRS) for control of insecticide-resistant mosquitoes was evaluated in experimental huts in Burkina Faso. Anopheles gambiae from the area is resistant to pyrethroids and to a lesser extent, carbamates. Relatively low mortality rates were observed with the LLIN (44%), IRS (42%), and CTPS (52%), whereas both combinations killed significantly more mosquitoes (~70% for LLIN + CTPS and LLIN + IRS). Blood feeding by An. gambiae was uninhibited by IRS and CTPS compared with LLIN (43%), LLIN + CTPS (58%), and LLIN + IRS (56%). No evidence for selection of the kdr and ace-1R alleles was observed with the combinations, whereas a survival advantage of mosquitoes bearing the ace-1R mutation was observed with IRS and CTPS. The results suggest that the combination of the two interventions constitutes a potential tool for vector-resistance management.  相似文献   
974.
975.
Four catechins, epigallocatechin-3-gallate, epigallocatechin, epicatechin-3-gallate, and epicatechin, inhibited activity of the Na+,K+-ATPase. The two galloyl-type catechins were more potent inhibitors, with IC50 values of about 1 μM, than were the other two catechins. Inhibition by epigallocatechin-3-gallate was noncompetitive with respect to ATP. Epigallocatechin-3-gallate reduced the affinity of vanadate, shifted the equilibrium of E1P and E2P toward E1P, and reduced the rate of the E1P to E2P transition. Epigallocatechin-3-gallate potently inhibited membrane-embedded P-type ATPases (gastric H+,K+-ATPase and sarcoplasmic reticulum Ca2+-ATPase) as well as the Na+,K+-ATPase, whereas soluble ATPases (bacterial F1-ATPase and myosin ATPase) were weakly inhibited. Solubilization of the Na+,K+-ATPase with a nonionic detergent reduced sensitivity to epigallocatechin-3-gallate with an elevation of IC50 to 10 μM. These results suggest that epigallocatechin-3-gallate exerts its inhibitory effect through interaction with plasma membrane phospholipid.  相似文献   
976.
Paragonimiasis is a common parasitic zoonosis in Cameroon and neighbouring countries in Western Africa. Serum, sputum and faecal samples were collected in an endemic area of South West Province, Cameroon, after administration of a questionnaire to identify individuals with appropriate symptoms and histories. Microscopic examination revealed eggs in sputum from 16 people, but none in any faecal sample. These 16 were among the 25 and 26 people, respectively, positive by ELISA and by immunoblot using Paragonimus africanus crude antigens. Copro-DNA detection was attempted using 23 faecal samples (18 from sputum egg-negative and five from sputum egg-positive individuals). Copro-DNA was detected in four of the five sputum egg-positive individuals. These results strongly suggest that: (1) serology is much more sensitive than sputum examination for diagnosis of paragonimiasis; and (2) a copro-DNA test may be more sensitive than a microscopic search for eggs in faeces. Molecular sequence data from ITS2 and cox1 genes confirmed that adult worms experimentally raised in cats were P. africanus and that eggs from sputum or other worm products from human faeces also belonged to this species. Based on these results, 26 of 168 persons (15.5%) were diagnosed as suffering from paragonimiasis.  相似文献   
977.
Purpose  We developed a lactoferrin conjugate by modifying bovine lactoferrin (bLF) with a 40-kDa branched poly(ethylene glycol) (PEG) molecule (designated 40 k-PEG-bLf), and we evaluated its in vitro activities and pharmacokinetic properties. Materials and Methods  We prepared 40k-PEG-bLf by amino conjugation with N-hydroxysuccinimide-activated PEG. This conjugate was purified by cation exchange chromatography and its in vitro biological activities, such as iron binding, anti-inflammatory effects, and resistance to proteolytic enzymes were investigated. In vivo pharmacokinetics analyses, were also performed to examine the rate of clearance from the plasma in rats. Results  The 40k-PEG-bLf conjugate was fully active in iron binding and exhibited 97.1 ± 5.5% (mean ± S.E., n = 6) of the original anti-inflammatory activity. The in vitro peptic susceptibility of 40 k-PEG-bLf revealed that the proteolytic half-life increased at least 6-fold that of unmodified LF. This PEGylated conjugate demonstrated a plasma half-life that was 8.7-fold longer than that of the unmodified bLF in rats. Conclusions  The 40k-PEG-bLf exhibited improved in vitro bioactivity and stability and enhanced pharmacokinetic properties as compared to those of the unmodified bLF and the 20 k-PEG-bLf conjugate, which was recently developed by PEGylation of bLF with a 20-kDa branched PEG [Nojima Y. et al. Bioconjugate Chem. 19:2253–2259 (2008)].  相似文献   
978.
979.
T cell Ig mucin 1 (TIM-1) plays an important role in regulating immune responses in autoimmune and asthma models, and it is expressed on both Th1 and Th2 cells. Using an antagonistic TIM-1-specific antibody, we studied the role of TIM-1 in alloimmunity. A short course of TIM-1-specific antibody monotherapy prolonged survival of fully MHC-mismatched vascularized mouse cardiac allografts. This prolongation was associated with inhibition of alloreactive Th1 responses and preservation of Th2 responses. TIM-1-specific antibody treatment was more effective in Th1-type cytokine-deficient Stat4(-/-) recipients as compared with Th2-type cytokine-deficient Stat6(-/-) recipients. Subtherapeutic doses of rapamycin plus TIM-1-specific antibody resulted in allograft acceptance and prevented the development of chronic allograft vasculopathy. Allograft survival via this treatment was accompanied by a Th1- to Th2-type cytokine switch. Depletion of natural Tregs abrogated the graft-protecting effect of the TIM-1-specific antibody. Importantly, CD4(+)CD25(+) Tregs obtained from long-term survivors had enhanced regulatory activity as compared with naive CD4(+)CD25(+) Tregs. Consistent with this, TIM-1-specific antibody treatment both preserved Tregs and prevented the expansion of alloreactive effector Th1 cells in an alloreactive TCR transgenic adoptive transfer model. These studies define previously unknown functions of TIM-1 in regulating alloimmune responses in vivo and may provide a novel approach to promoting transplantation tolerance.  相似文献   
980.
Patients with severe neurological disorders often require enteral nutrition (EN). Since long-term EN can cause multiple complications, reinstating the oral intake of food is beneficial. Olfactory stimulation using black pepper oil (BPO), a strong appetite stimulant, was reported to facilitate swallowing in older people. Therefore, the effects of olfactory stimulation with BPO were investigated in pediatric patients receiving long-term EN due to neurological disorders. The effects of scenting with BPO for 1 min immediately before every meal were evaluated in ten patients: 4 boys and 6 girls, aged 19-97 months (51 +/- 26 months). The neurological disorders included periventricular leukomalacia (3 patients), hypoxic ischemic encephalopathy (3), Costello syndrome (1), Russell-Silver syndrome (1), Miller-Dieker syndrome (1), and cerebral palsy of unknown etiology (1). In eight of these patients, BPO intervention was continued for 3 months. Five of these eight patients showed increases in the amount of oral intake with desirable effects including facilitated swallowing movement, although complete elimination of the need for EN was not achieved. In the other three patients, BPO intervention was not effective; severe cerebral tissue loss, profound malformation or intractable seizures seemed to reduce the efficacy of BPO. In two cases, BPO intervention was discontinued due to cough or because the odor of BPO was unbearable to the family. In conclusion, olfactory stimulation with BPO facilitated oral intake in a subset of patients on long-term EN. BPO stimulation may be useful for facilitating oral intake when used in combination with conventional methods.  相似文献   
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