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51.

Purpose  

The goal of this study was to develop a method to reduce the costs of intraoperative high-field magnet resonance imaging (iMRI). The results of a series of 29 gliomas removed with this technique are presented.  相似文献   
52.
Context: (-)-α-Bisabolol (BISA) is a sesquiterpene alcohol widely used as scent in cosmetic preparations, perfumes, shampoos, toilet soaps and other toiletries with potential for use in the pharmaceutical area.

Objective: To evaluate the corneal antinociceptive efficacy of BISA and to analyze the best solubilizing agent.

Materials and methods: Acute corneal nociception was induced by the local application of hypertonic saline (5 M NaCl; 20?μL) to the corneal surface of Swiss mice (n?=?8/group) 60?min after topical treatment with solutions or ointment containing BISA (50–200?mg/mL). The number of eye wipes performed with the ipsilateral forepaw was counted for a period of 30?s. Control groups (vehicles) were included.

Results: BISA (50, 100 or 200?mg/mL) solubilized with Tween 80 did not reduce the number of eye wipes. Animals treated with the ointment (BISA 50, 100 or 200?mg/mL; p?p?Discussion and conclusion: BISA possess corneal antinociceptive activity. Although the ointment presented antinociceptive effect, it is concluded that BISA when associated with propylene glycol has better potential for corneal nociceptive pain since it is more comfortable to use, leading to greater acceptance by patients.  相似文献   
53.
54.
Fibroadenomas are the most common benign breast tumors, occurring mainly in young women. Their responses to the hormonal environment are similar to those of normal breast tissue, which suggests that steroid receptors may play a role in tumor development. We evaluated the gene and protein expression of progesterone receptors A and B (PRA and PRB) and the protein expression of estrogen receptor α (ER-α) in fibroadenoma samples, comparing with adjacent normal breast tissue, from 11 premenopausal women. Progesterone and estradiol levels were determined. No alterations in the PRs gene and protein expression and the ER-α protein expression were observed between the follicular and luteal phases, in normal breast versus fibroadenomas. Protein levels of PRA and PRB were higher in fibroadenomas compared to normal breast tissue (P = 0.038 and P = 0.031), while the PRs mRNA levels were similar in both tissues (P = 0.721 and P = 0.139). There were no differences in ER-α protein expression between normal breast tissue and fibroadenomas (P = 0.508). The PRA:PRB ratio was similar in the tissues, and also showed a strong correlation in both (r = 0.964, P = 0.0001). Our data suggest a role of PRs in the growth and development of fibroadenomas, although without alterations of the PRA:PRB ratio in these tumors. The absence of alterations in ER-α protein levels could be a characteristic behavior of fibroadenomas, unlike breast cancer.  相似文献   
55.
Purpose To describe a young patient with choroidal neovascularization, associated with Stargardt’s disease, who underwent treatment with intravitreal ranibizumab. Methods A 26-year-old man with a diagnosis of Stargard’s disease presented at our department for sudden decreased vison in his right eye (20/800). Upon a complete oplthamologic examination, including fluorescein angiography (FA), indocyanine green angiography (ICGA) and optical coherence tomography (OCT), the patient was diagnosed with subfoveal CNV of the right eye. Owing to the subfoveal localization of the CNV, intravitreal ranibizumab injection was performed on this young patient. Results Three months after the last intravitreal injection of ranibizumab, fundus biomicroscopy, FA, ICGA and OCT revealed the CNV closure and total resolution of the associated cistoid macular edema and serous retinal detachment, with no recurrence and no complication from the intravitreal injection of ranibizumab. Visual acuity improved only to 20/400. Conclusion Intravitreal ranibizumab injection seems to induce total regression of CNV complicating Stargardt’s disease. Further investigations are required to confirm our results. The authors have no proprietary interest in the materials used in this study.  相似文献   
56.
PURPOSE: To classify the preoperative and postoperative optical coherence tomography (OCT) findings for subfoveal choroidal neovascularization (CNV) related to high myopia and multifocal choroiditis (MFC) and to correlate these findings with surgical outcome. METHODS: Ten consecutive patients presenting with subfoveal CNV related to either MFC or degenerative myopia were evaluated. Each patient underwent a biomicroscopic examination, fluorescein and indocyanine green angiographies, as well as OCT before and after surgical removal of CNV. Four different parameters were considered in the analysis of all OCT scans: tissue reflectivity, location of the CNV band, presence or absence of a separation zone, and reflectivity underneath the retinal pigment epithelium (RPE) band. RESULTS: For all six eyes with MFC, OCT showed a hyperreflective band anterior to the RPE with a separation zone and an optically clear zone underneath the RPE. Visual acuity improved in all six eyes. For the degenerative myopia group (4 eyes), OCT revealed findings similar to those observed for MFC for 1 eye, which had a favorable postoperative outcome. The remaining three myopic eyes with different OCT patterns had poor postoperative outcomes. CONCLUSION: Optical coherence tomography can provide preoperative clues for submacular surgery. Eyes with CNV located anterior to and separated from the RPE that have an "optically clear zone" underneath are the best candidates for surgical removal. Such a feature was correlated with a good postoperative outcome.  相似文献   
57.
1. The direct and endothelium-dependent effects of lipopolysaccharide (LPS) were investigated on resistance and conductance arteries from normotensive Wistar (NWR) and spontaneously hypertensive (SHR) rats. 2. In both NWR and SHR, LPS induced dose-dependent relaxations of the mesenteric vascular bed, which were inhibited by L-NNA in SHR but not in NWR. Iberiotoxin (IBTX) inhibited the responses to LPS in both groups, indicating the participation of high conductance Ca(2+)-dependent K(+) channels. 3. In mesenteric artery rings, the resting membrane potentials and the hyperpolarizing responses of NWR to LPS did not differ in endothelized and denuded preparations but L-NNA inhibited the responses only in endothelized rings. These responses were reduced by bosentan, suggesting that endothelin release may mask a possible hyperpolarizing response to LPS. The hyperpolarizing responses to LPS were blocked by IBTX in both endothelized and de-endothelized NWR rings. In the SHR only intact rings showed hyperpolarization to LPS, which was inhibited by IBTX and byL-NNA. 4. In SHR aortic endothelized or denuded rings, LPS induced hyperpolarizing responses which, in endothelized rings, were partially blocked by L-NNA, by IBTX or by glibenclamide, but totally abolished by IBTX plus glibenclamide. No response to LPS was observed in NWR aortic rings. 5. Our results indicate that LPS activates large conductance Ca(2+)-sensitive K(+) channels located in the smooth muscle cell membrane both directly and indirectly, through NO release from the endothelium in NWR, whereas NO is the major mediator of the LPS responses in SHR resistance vessels.  相似文献   
58.
This study evaluates the self-esteem of undergraduate students of nursing, that through a workshop developed mechanisms for improving their self-esteem, considering that this is the most propitious time for students to multiply health care actions. Methodology: the research was carried out with 156 undergraduate students of the third year. Socio-drama techniques of Neurolinguistics were used and the evaluation was done according to Minayo. It was possible to observe that students usually confuse self-esteem and self-image, and that both are stereotyped for for men and women. As nurses are always worried about the client/patient's life quality, they neglect themselves. In this case, the Workshops were essential for the students to rescue interior knowledge about themselves, and to realize that in order to take good care of clients/patients, they must be physically and psychologically healthy.  相似文献   
59.
Disintegrins are small peptides isolated from the venom of several snake families which act as integrin-antagonists or agonists, interacting with a variety of biological processes mediated by integrins. In this work we describe five new disintegrin-like domains within metalloproteinase precursor sequences, obtained from a Bothrops jararaca venom gland cDNA library. Among the new disintegrin-like domains, four were contained in PIII metalloproteinase precursors, with three of them presenting ECD-motifs and one presenting a new KCD-motif. Moreover, we found three disintegrin-like domains within PII metalloproteinase precursors. Two of them are similar to the already described disintegrins jarastatin and jararacin. The third molecule is unusual, presenting some typical PIII metalloproteinase characteristics but lacking the cysteine-rich domain being, thus, classified as a PII metalloproteinase. Only few reports presented molecules with these characteristics. Sequence analysis suggests that these molecules are intermediate steps between the more ancient PIII and the more recent PII metalloproteinases. We also investigated disintegrin N-terminus diversity in B. jararaca crude venom by purifying jarastatin and jararacin and analyzing them by mass spectrometry.  相似文献   
60.
The possible correlation among Epstein-Barr virus (EBV) load, interleukin-6 (IL-6) and interleukin-10 (IL-10) levels has become an attractive issue and can provide a useful tool for diagnosis and monitoring of patients at risk for post-transplant lymphoproliferative disease (PTLD) development. At the time of diagnosis of PTLD, 11 patients were prospectively enrolled and 55 nested controls were selected from a 1800 renal transplant cohort. Real-time polymerase chain reaction (PCR) was used to quantify EBV load in peripheral blood mononuclear cells (PBMC). Serum IL-6 and IL-10 levels were determined using an enzyme-linked immunosorbent assay (ELISA). The median EBV load of PTLD cases was 17400 copies/10(6) PBMC, statistically different from controls (P=0.001). The median IL-6 level of PTLD cases was not different from controls (P=0.079). However, median IL-10 levels showed a significant difference in both groups (P < or = 0.001). The receiver-operating characteristic (ROC) curve analysis was applied to estimate the IL-10 cut-off value predictive of PTLD development. We found that 73.5 pg/ml has high sensitivity (1.00) and specificity (0.85). Also, Pearson's analysis showed a strong correlation between EBV load and serum IL-10 concentration (P < or = 0.001). This nested case-control study demonstrates that EBV load at diagnosis of PTLD correlates with IL-10 levels, and that monitoring of IL-10 can provide a less expensive and less time-consuming tool for PTLD diagnosis and close follow-up of patients at risk. Furthermore, we were able to define a cut-off value of IL-10 mostly predictive of PTLD development in this cohort. Our data suggest that serial measurements prior to PTLD development must be carried out to validate our hypothesis.  相似文献   
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