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1.
Synthetic amorphous silica (SAS) in its nanosized form is now used in food applications although the potential risks for human health have not been evaluated. In this study, genotoxicity and oxidative DNA damage of two pyrogenic (NM‐202 and 203) and two precipitated (NM‐200 and ‐201) nanosized SAS were investigated in vivo in rats following oral exposure. Male Sprague Dawley rats were exposed to 5, 10, or 20 mg/kg b.w./day for three days by gavage. DNA strand breaks and oxidative DNA damage were investigated in seven tissues (blood, bone marrow from femur, liver, spleen, kidney, duodenum, and colon) with the alkaline and the (Fpg)‐modified comet assays, respectively. Concomitantly, chromosomal damage was investigated in bone marrow and in colon with the micronucleus assay. Additionally, malondialdehyde (MDA), a lipid peroxidation marker, was measured in plasma. When required, a histopathological examination was also conducted. The results showed neither obvious DNA strand breaks nor oxidative damage with the comet assay, irrespective of the dose and the organ investigated. Similarly, no increases in chromosome damage in bone marrow or lipid peroxidation in plasma were detected. However, although the response was not dose‐dependent, a weak increase in the percentage of micronucleated cells was observed in the colon of rats treated with the two pyrogenic SAS at the lowest dose (5 mg/kg b.w./day). Additional data are required to confirm this result, considering in particular, the role of agglomeration/aggregation of SAS NMs in their uptake by intestinal cells. Environ. Mol. Mutagen. 56:218–227, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
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This prospective clinic-based study evaluated the pretreatment periodontal status of the orthodontic patients seen at the University College Hospital, Ibadan, Nigeria, and assessed the relationship between dental aesthetic index (DAI) scores and periodontal status according to community periodontal index of treatment needs (CPITN) scores. One hundred forty five patients-70 (48.3%) males and 75 (51.7%) females from 6 to 45 years (mean 15.8 +/- 7.5)-were seen. World Health Organization (WHO) guidelines were followed in the examination and reporting of the periodontal status, and DAI scores were assessed based on WHO guidelines. The chi-square test was used to determine the association between the DAI and the CPITN scores. Most patients were in the 6-15 (55.9%) or 16-25 (35.9%) age groups. Based on the WHO preferred cumulative calculations of treatment need (TN), 35.2% of the patients had TN 0, 64.9% had TN 1, 24.9% had TN 2, and only 0.7% had TN 3. The relationship between DAI scores and periodontal treatment needs was not statistically significant (P >.05). Although many patients were yet to attain the WHO goal of no more than 1 sextant affected by bleeding or calculus at the age of 15, over one third had satisfactory periodontal health.  相似文献   
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Proprioception plays an integral role in neuromotor control of the knee joint and deficits in knee joint proprioception are well documented in individuals with knee osteoarthritis (OA). However, the functional relevance of these deficits is not clear. This cross-sectional study evaluated the relationship between knee joint proprioception and pain and disability in a large cohort of individuals with knee OA. Two hundred and twenty participants (145 F, 75 M) with symptomatic knee OA were recruited from the community. Five non-weight bearing active tests with ipsilateral limb matching responses were performed at 20 degrees and 40 degrees flexion to measure knee joint position sense. Pain and disability were assessed by self-reported questionnaires and objective measures of balance and gait. Results showed little association between knee joint position sense variables and measures of pain and disability (r values <0.24, most p>0.05). When comparing participants with the worst and best joint position sense, no significant differences in pain and disability could be found (p>0.05). While our study design does not allow causality to be established, these results suggest that deficits in joint position sense may be due to factors other than pain and that deficits are not large enough to impact upon disability.  相似文献   
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OBJECTIVE: To evaluate the efficacy of methylphenidate in treating adults with attention-deficit hyperactivity disorder (ADHD), using subjective (self-report) and objective (computerized test) measures. METHOD: This double-blind crossover trial of placebo vs methylphenidate included subjects with childhood and current ADHD symptoms, IQs above 80, no other psychiatric condition explaining their difficulties or requiring other treatment, and no substance abuse in the previous 6 months. We administered 10 mg 3 times daily of medication (that is, placebo or methylphenidate) for 2 weeks. On the final day, subjects completed self-report measures and were tested on computerized tests. We then increased dosage to 15 mg 3 times daily for 2 weeks and administered a complete reassessment on the final day. Following a 1-week washout, we repeated this process on the second medication (that is, placebo or methylphenidate). RESULTS: Thirty adults with ADHD participated. Self-report measures and computerized tests showed significant improvements in ADHD symptoms on methylphenidate, compared with placebo. Other psychiatric symptoms (notably, anxiety and depression) were alleviated with methylphenidate. There was no significant difference between the 2 dosages of methylphenidate. CONCLUSION: Methylphenidate is effective in improving ADHD symptoms in adults with ADHD, is well tolerated, and has minimal side effects.  相似文献   
7.
CONTEXT: The knowledge of variations of the tympanic membrane (TM) perforations with the climatic changes in the West African subregion would help clinicians in its prevention and management. OBJECTIVE: To analyze the pattern of clinical presentations and associated features of TM perforation in adults in West Africa. DESIGN: A prospective study. SETTING: Tertiary referral centre, University hospital. PATIENTS OR OTHER PARTICIPANTS: Thirty-five (35) consecutive adults with TM perforations during a 1-year period had clinical evaluation of each TM using head mirror, video otoscopy, and micro-otoscopy. MAIN OUTCOME MEASURES: Clinical presentations and associated features of TM perforations. RESULTS: Thirty-five patients, 20 (57%) men and 15 (43%) women, with 42 perforated TMs were examined. Twenty-eight (80%) patients had unilateral perforations. Infection was responsible for 90.5% of cases, and trauma was responsible for the rest. Locations of perforations were central (29; 69.1%), anteroinferior (4; 9.5%), posteroinferior (4; 9.5%), anterosuperior (3; 7.1%), and posterosuperior (2; 4.8%). The sizes of the perforations ranged from 1.2 to 83.2%. Large sizes of 25% and more were found to occur in humid and wet seasons, and also, clinical presentations of otorrhea (65.6%), otalgia (51.5%), tinnitus (37.1%), and ear itching (34.4%) seemed to worsen. CONCLUSION: Most TM perforations result from infection and are preventable via appropriate health education. Posterosuperior perforation is rare, and this is probably one of the factors making choleasteatoma uncommon in West Africa. Approximately 83.3% of TM perforations measure more than 25% in size and appear during the wet humid season of the year. These findings are important for both local and foreign otolaryngologists who may be practicing in this subregion of the world.  相似文献   
8.
Journal of Occupational Rehabilitation - Purpose Little is currently known about how early intervention vocational rehabilitation (EIVR) works for people with newly acquired neurological conditions...  相似文献   
9.

Inflammatory breast cancer (IBC) is a rare and aggressive breast cancer characterized by erythema and edema of at least one-third of the breast. The diagnosis remains a clinical one. Standard of care involves trimodality therapy with anthracycline-based neoadjuvant chemotherapy and human epidermal growth factor receptor 2 (HER2)-directed therapy if HER2 positive, followed by modified radical mastectomy and post-mastectomy radiation therapy to the chest wall in addition to regional nodal basins including supraclavicular and internal mammary nodes. Current evidence does not support de-escalation of surgical therapy in the breast and axilla in IBC, and positive surgical margins have been associated with worse outcomes. Furthermore, sentinel node biopsy for axillary staging has a high false negative rate prohibiting its use in IBC. Delayed reconstruction is recommended for IBC due to a high recurrence rate and a potential for delay in adjuvant therapy. Contralateral prophylactic mastectomy may be considered at the time of delayed reconstruction. In this paper, we discuss available evidence and controversies in the current surgical management of patients with IBC.

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10.
Serotonin is a directly-acting hyperalgesic agent in the rat.   总被引:19,自引:0,他引:19  
Y O Taiwo  J D Levine 《Neuroscience》1992,48(2):485-490
In this study, we have investigated serotonin hyperalgesia employing the mechanical paw withdrawal nociceptive threshold test in the rat. Intradermally injected serotonin was found to produce a dose-dependent hyperalgesia that was not attenuated by procedures which eliminate the known indirect mechanisms of hyperalgesia such as sympathectomy, polymorphonuclear leukocyte depletion or cyclooxygenase inhibition. In addition, the latency to onset of serotonin hyperalgesia is extremely short, with maximal hyperalgesia observed in less than 1 min, a similar temporal onset to direct-acting hyperalgesic agents such as prostaglandin E2. The results suggest, therefore, that the hyperalgesic effects of serotonin in our animal model are exerted by direct action on primary afferent neurons. Only the intradermal injection of selective serotonin (5-hydroxytryptamine; 5-HT) agonists for the 1A receptor subset (5-HT1A), (+/-)-2-dipropylamino-8-hydroxy-1,2,3,4-tetrahydronaphthaline hydrobromide and N,N-dipropyl-5-carboxamido-tryptamine maleate, produced dose-dependent hyperalgesia. No hyperalgesia was seen after 5-HT1B, CGS-12066B maleate and m-trifluoromethylphenyl-piperazine hydrochloride; 5-HT2+IC, alpha methyl 5HT and (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane HCl; or 5-HT3, 2-methyl-5-hydroxytryptamine maleate and phenylbiguanide, agonists. Similarly, only the 5-HT1A antagonists, spiroxatrine and spiperone, attenuated the hyperalgesia induced by intradermally injected serotonin. 5-HT2+IC antagonists, mesulergine and ketanserin, and 5-HT3 antagonists, quipazine and 3-tropanyl-indole-3-carboxylate, did not significantly attenuate 5-HT hyperalgesia. We conclude that serotonin produces hyperalgesia by a direct action on the primary afferent neuron via the 5-HT1A subset of serotonin receptors.  相似文献   
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