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排序方式: 共有9907条查询结果,搜索用时 15 毫秒
81.
Fernando Pretel Rute M Gon?alves-de-Andrade Fabio Carlos Magnoli Maria Esther R da Silva Jorge M C Ferreira Carmen W van den Berg Denise V Tambourgi 《Toxicon》2005,45(4):449-458
Loxosceles adelaida spiders (Araneae, Sicariidae) are found near and inside the caves in the Parque Estadual Turistico do Alto Ribeira (PETAR), Sao Paulo, Brazil, which are visited by thousands of tourists every year. Several Loxosceles species are a public health problem in many regions of the world, by causing severe dermonecrosis and/or complement dependent haemolysis upon envenomation. The aim of this study was to characterize the biochemical and biological properties of L. adelaida venom and evaluate the toxic potential of envenomation by this non-synanthropic Loxosceles species. The biological activities of the L. adelaida venom was compared to that of Loxosceles gaucho, a synanthropic species of medical importance in Brazil. L. adelaida venom showed a similar potential to induce haemolysis, dermonecrosis and lethality as L. gaucho venom. L. adelaida crude venom was purified, yielding a 31 kDa component endowed with haemolytic and dermonecrotic activities. In conclusion, we show here that the troglophile Loxosceles species, L. adelaida, commonly found in the complex of caves from PETAR, is potentially able to cause envenomation with the same gravity of those produced by synanthropic species. 相似文献
82.
Esther Rieger-Fackeldey Annegret Hofmiller Andreas Schulze 《The journal of maternal-fetal & neonatal medicine》2006,19(1):49-55
OBJECTIVE: To determine characteristics of breathing patterns prior to respiratory pauses in extremely low birth weight (ELBW) infants breathing spontaneously under proportional assist ventilation (PAV). METHODS: Thirteen infants (mean +/- SD: gestational age 25 +/- 1 weeks; birth weight 753 +/- 149 g; age 4 +/- 3 days) were studied. Recordings were obtained under PAV over two-hour periods on two consecutive days. The last 10 breaths preceding respiratory pauses were analyzed. RESULTS: Tidal volume, inspiratory and expiratory peak flow, and mean inspiratory flow decreased in the last breaths prior to respiratory pauses compared to all other breaths (p < 0.001). Of all apneas 89% were preceded by a decrease in tidal volume of at least 33% (435/487; p < 0.001). The positive predictive value of a decrease in tidal volume to predict an apnea was 26% (435/1640; p < 0.001). CONCLUSIONS: Decreases in tidal volume of at least 33% and in airflow are the predominant changes in the breathing pattern prior to respiratory pauses in ELBW infants, preceding 89% of all respiratory pauses. Their low positive predictive value of 26% however, indicates that further variables of breathing need to be implemented to predict cessation of breathing with higher precision. 相似文献
83.
Esther G C Troost Johan Bussink Johannes H A M Kaanders Julli?tte van Eerd Johannes P W Peters Paulus F J W Rijken Otto C Boerman Albert J van der Kogel 《Radiotherapy and oncology》2005,76(2):194-199
PURPOSE: In head and neck cancer, it has been shown that hypoxic tumors respond poorly to therapy. Methods to identify hypoxic tumors are, therefore, of importance to select patients for oxygenation modifying or other intensified treatments. The aim of this study was to compare tumor cell hypoxia assessed by the hypoxic cell marker pimonidazole (PIMO) with expression of the endogenous hypoxia-related marker carbonic anhydrase IX (CAIX) in three human head and neck tumor lines. MATERIAL AND METHODS: Forty-five tumors of three human head and neck tumor lines, SCCNij3, SCCNij59 and MEC82, xenografted in athymic mice, were used. CAIX was quantified by biodistribution (% injected dose/g tumor) after injecting 3-5 microl 111In-labeled G250 mouse antibody 3 days prior to euthanizing. In a tissue section from the same tumor, fractions of tumor area positive for PIMO, CAIX and Hoechst 33342 (perfusion marker) were assessed after immunohistochemical staining, using a digital image analysis system. RESULTS: SCCNij3 and MEC82 were relatively hypoxic tumor lines with fractions of tumor area positive for pimonidazole of 0.16 and 0.15, respectively. SCCNij59 was a better-oxygenated tumor line with a PIMO-fraction of 0.03. The three tumor lines showed different levels and patterns of CAIX immunohistochemical staining, but only in MEC82 there was a good correlation between PIMO-fraction and CAIX-fraction (r2=0.92, P<0.0001). Correlations between 111In-G250 uptake and CAIX-fraction or PIMO-fraction within tumor lines were weak or absent. CONCLUSIONS: Assessment of CAIX expression depends largely on the techniques and tumor lines used. Furthermore, the immunohistochemical staining pattern of CAIX relative to PIMO differs between human tumor lines of similar anatomical origin. Therefore, the use of CAIX as endogenous marker of tumor hypoxia remains questionable. 相似文献
84.
Rosalie M Luiten Esther W M Kueter Wolter Mooi Maarten P W Gallee Elaine M Rankin Winald R Gerritsen Shirley M Clift Willem J Nooijen Pauline Weder Willeke F van de Kasteele Johan Sein Paul C M van den Berk Omgo E Nieweg Anton M Berns Hergen Spits Gijsbert C de Gast 《Journal of clinical oncology》2005,23(35):8978-8991
PURPOSE: To determine the feasibility, toxicity, and immunologic effects of vaccination with autologous tumor cells retrovirally transduced with the GM-CSF gene, we performed a phase I/II vaccination study in stage IV metastatic melanoma patients. PATIENTS AND METHODS: Sixty-four patients were randomly assigned to receive three vaccinations of high-dose or low-dose tumor cells at 3-week intervals. Tumor cell vaccine preparation succeeded for 56 patients (88%), but because of progressive disease, the well-tolerated vaccination was completed in only 28 patients. We analyzed the priming of T cells against melanoma antigens, MART-1, tyrosinase, gp100, MAGE-A1, and MAGE-A3 using human leukocyte antigen/peptide tetramers and functional assays. RESULTS: The high-dose vaccination induced the infiltration of T cells into the tumor tissue. Three of 14 patients receiving the high-dose vaccine showed an increase in MART-1- or gp100-specific T cells in the peripheral blood during vaccination. Six patients experienced disease-free survival for more than 5 years, and two of these patients developed vitiligo at multiple sites after vaccination. MART-1- and gp100-specific T cells were found infiltrating in vitiligo skin. Upon vaccination, the T cells acquired an effector phenotype and produced interferon-gamma on specific antigenic stimulation. CONCLUSION: We conclude that vaccination with GM-CSF-transduced autologous tumor cells has limited toxicity and can enhance T-cell activation against melanocyte differentiation antigens, which can lead to vitiligo. Whether the induction of autoimmune vitiligo may prolong disease-free survival of metastatic melanoma patients who are surgically rendered as having no evidence of disease before vaccination is worthy of further investigation. 相似文献
85.
Metastases to the scapula and distal sites on the upper and lower extremities are infrequent. Although these metastases tend to occur in patients with advanced disease, a distal metastasis is occasionally the sole metastatic location. Distal metastases do not pose an immediate threat to a patient's life; however, they may cause significant pain and disability. Appropriate management can considerably enhance function, quality of life, and, occasionally, survival. Seven cases of distal metastasis are presented in this article with discussion of operative and nonoperative approaches to management. 相似文献
86.
Olga Laporta-Hoyos Júlia Ballester-Plané David Leiva Teresa Ribas Júlia Miralbell Clara Torroja-Nualart Maria Eugenia Russi Esther Toro-Tamargo Mar Meléndez-Plumed Francisca Gimeno Alfons Macaya Roser Pueyo 《European journal of paediatric neurology》2019,23(4):546-559
AimTo comprehensively describe intellectual and executive functioning (EF) in people with dyskinetic cerebral palsy (DCP), by comparing their performance with that of: 1) age- and sex-matched typically developing controls (TDC); and 2) participants with spastic cerebral palsy (SCP) matched for age, sex, term/preterm and gross motor function classification system (GMFCS).MethodThis cross-sectional study was conducted by the University of Barcelona in collaboration with five institutions. Participants were people with DCP (n = 52; 24 females, median age 20.5 y: 5mo, interquartile range [IQR] = 13.75 y: 7mo; GMFCS I–V). As comparison groups, participants with SCP (n = 20; 10 females, median age = 20.5 y: 5.5mo, IQR = 13.75 y 9mo; GMFCS I–V) and TDC (n = 52; 24 females, median age = 20 y: 4mo, IQR = 12 y 7mo) were included. Intelligence and EF were assessed using common tests in all participants.ResultsBoth CP groups had lower intelligence than TDC and performed poorer in almost all EF tasks. Intelligence was higher in DCP than SCP (z = ?2.51, p = 0.01). Participants with DCP also performed significantly better in goal-setting tasks (z = 2.27, p = 0.03) and information processing (z = ?2.54, p = 0.01) than those with SCP.ConclusionPeople with DCP present lower general intellectual functioning and poorer EF across multiple domains than typically developing controls. People with DCP have higher general intellectual functioning and better EF than people with SCP when levels of motor severity are similar. 相似文献
87.
88.
Esther Navarro-Escobar Pilar Baca Matilde Ruiz-Linares Maria Teresa Arias-Moliz Mercedes Perez-Heredia Carmen Maria Ferrer-Luque 《Acta odontologica Scandinavica》2014,72(8):819-824
Objective. The aim of this study was to compare the efficacy of different dentine adhesives in delaying the coronal bacterial leakage of Enterococcus faecalis in filled root canals. Materials and methods. Ninety-five lower incisors of patients >65 years of age were instrumented using the ProTaper® system and were irrigated with 1 mL of 2.5% sodium hypochlorite (NaOCl) alternated with 1 mL 17% EDTA between each file change. Final irrigation was performed with 5 mL of 17% EDTA and then flushed with 5 mL of distilled water. The teeth were randomly divided into five experimental groups (n = 15/group) and one of the following dentine adhesives was applied: (1) AdheSE®; (2) Excite® DSC; (3) Clearfil? Protect Bond; (4) One Coat 7.0; or (5) Control group without adhesive. After filling the root canals, the samples were mounted on a double chamber device to evaluate the bacterial filtration of E. faecalis during a period of 240 days. The results underwent non-parametric Kaplan-Meier survival analysis and comparisons among groups were done using the Log-Rank test. Results. At 240 days, E. faecalis was detected in samples of all groups in the lower chamber. The highest survival value was obtained by One Coat 7.0, giving statistically significant differences from the other groups, whereas Clearfil? Protect Bond, AdheSE® and Excite® DSC showed similar behaviours, likewise similar to the Control group. Conclusions. One Coat 7.0 adhesive system provides the longest survival value to delay E. faecalis coronal leakage in filled root canals. 相似文献
89.