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Wilfried Smidt Gisela Kammermeyer Susanna Roux Christiane Theisen Christian Weber 《Early child development and care》2018,188(10):1340-1353
The career success of preschool teachers has been discussed to be important because it can be a precondition for the ability to provide a high-quality preschool education. Consequently, the identification of factors that can help explain individual differences in career success is a crucial research issue. Previous research covering various occupations indicates that the Big Five, internal locus of control (LOC), and occupational self-efficacy are good predictors of objective and subjective career success. However, there is a research gap on this topic in preschool teachers. This study examined whether the Big Five, LOC, and occupational self-efficacy could predict the career success of 560 preschool teachers in Germany. After controlling for other predictors, internal LOC corresponded with higher objective career success, but neuroticism and conscientiousness corresponded with lower subjective career success. Occupational self-efficacy corresponded with higher subjective career success. The findings are discussed with respect to practical conclusions. 相似文献
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Smidt ML Janssen CM Barendregt WB Wobbes T Strobbe LJ 《American journal of surgery》2004,187(6):684-687
BACKGROUND: A sentinel lymph node (SLN) biopsy in breast cancer patients, performed under local anesthesia (LA), could have advantages such as more efficient use of operating room time and pathologist time. It also provides a histologic diagnosis before definitive breast surgery is undertaken. The aim of this study was to assess feasibility by comparing the results of SLN procedures performed under LA versus general anesthesia (GA). METHODS: The SLN procedure was performed in 50 consecutive outpatients and 167 inpatients with clinical T1-2N0 breast cancer while they were under LA and GA, respectively. The SLN detection rate, a comparison of mapped and harvested SLNs, was compared for both groups. The duration of the SLN biopsies performed under LA was also measured. RESULTS: For both groups a median of 2 SLNs/patient were harvested. The detection rate was 1.00 for the LA group and 0.99 for the GA group. The learning curve for SLN procedures under LA showed a decrease in duration for the consecutive months (not significant). CONCLUSIONS: SLN biopsy can be safely and adequately performed with the patient under LA. It allows early diagnosis of the lymph node status, acquired on an outpatient basis, with minimal discomfort to the patient. The learning curve demonstrated that the LA procedure can quickly be mastered if the surgeon is experienced in performing SLN biopsies. 相似文献
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Suzan Lenz Svend Lindenberg Karin Sundberg Anders Nyboe Andersen Peter Horness Jørgen Starup Claus Yding Andersen Steen Smidt Jensen Anders Hay-Schmidt 《Journal of assisted reproduction and genetics》1991,8(5):272-275
Treatment of 26 women with tubal infertility was attempted using intrauterine capsules loaded with oocytes and spermatozoa. The stimulation protocol was as used for in vitro fertilization and embryo transfer and consisted of short-term use of Buserelin, human menopausal gonadotropin, and human chorionic gonadotropin. Oocytes were collected by ultrasonically guided transvaginal aspiration, and spermatozoa were prepared by swim-up technique. The gametes were placed in agar capsules 4 hr after oocyte collection, and the capsules were introduced to the uterine fundus using an insertion tube and piston from an intrauterine device. Six complete capsules and parts of two other capsules were expelled. None of the women became pregnant, compared with a pregnancy rate of 21% per aspiration following in vitro fertilization and embryo transfer during the same period. 相似文献
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Cuppen JG Crum SJ Van den Heuvel HH Smidt RA Van den Brink PJ 《Ecotoxicology (London, England)》2002,11(3):165-180
Effects of chronic application of a mixture of the insecticides chlorpyrifos and lindane were studied in indoor freshwater microcosms. The exposure concentrations (based on 0, 0.005, 0.01, 0.05, 0.1 and 0.5 times the LC50 of the most sensitive standard test organism for each compound) were kept at a constant level for four weeks. The calculated mean concentrations for chlorpyrifos were found to be almost at their corresponding nominal level during the treatment period. The mean calculated lindane concentrations, however, were found to be 15–40% higher than intended. In the post treatment period both insecticides dissipated fast (t
1/2: chlorpyrifos 9 days, lindane 22 days) from the water phase. The concentrations of the mixture at the highest treatment level corresponded to 0.53 toxic units (TU) for Daphnia magna and 0.61 TU for the most sensitive fish. The decomposition of Populus leaves in litter bags was significantly lower at the three highest insecticide concentrations. The macroinvertebrate community was seriously affected at the three highest treatment levels, with Crustacea and the Chironomidae Corynoneura proving to be the most sensitive groups. Gastropoda and Oligochaeta were relatively insensitive and some taxa (e.g. Valvata piscinalis, juvenile Physa fontinalis, Nemertea and Stylaria lacustris) increased in numbers. The observed effects could be explained from the individual toxicity of the insecticides to the invertebrates, and did not indicate synergistic effects. A second paper (Van den Brink et al., 2002) addresses the effects on other endpoints, as well as the overall risk assessment of the insecticide mixture. 相似文献
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Intraoperative scrape cytology of the sentinel lymph node in patients with breast cancer 总被引:2,自引:0,他引:2
BACKGROUND: Intraoperative examination of the sentinel lymph node (SLN) may detect metastatic disease, allowing immediate axillary lymph node dissection and therefore avoiding the need for reoperation. The aim of this study was to evaluate the accuracy of scrape cytology of the SLN in patients with early breast cancer. METHODS: Sentinel node biopsy was performed in 148 patients with clinical T1-2 N0 breast cancer. After harvesting, the SLN was bisected and cells from both halves were scraped with a scalpel blade on to a slide and stained with a Papanicolaou and Giemsa stain. Scrape cytology results were compared with the results of paraffin sections stained with haematoxylin and eosin and with immunohistochemistry. RESULTS: The intraoperative diagnosis was correct in 126 patients (85 per cent). Sensitivity and specificity were 67 and 98 per cent respectively; positive and negative predictive values were 95 and 81 per cent. CONCLUSION: Scrape cytology is a useful method for intraoperative evaluation of the SLN in patients with breast cancer. 相似文献
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Oral Absorption of Peptides Through the Cobalamin (Vitamin B12) Pathway in the Rat Intestine 总被引:2,自引:0,他引:2
Alsenz J Russell-Jones GJ Westwood S Levet-Trafit B de Smidt PC 《Pharmaceutical research》2000,17(7):825-832
Purpose. This study was aimed at examining the extent and mechanismof uptake of cobalamin (Cbl)-conjugated peptides in vitro and in vivo.
Methods. To enable acquisition of quantitative absorption data ofCbl-peptides, metabolically stable octapeptides (DP3), with (Cbl-Hex-DP3)or without a hexyl spacer (Cbl-DP3), were coupled to Cbl andradiolabeled. For comparison, LHRH coupled to Cbl was used as metabolicallysusceptible peptide. Biological recognition of Cbl-peptides was studiedin the physiological order: binding by Intrinsic Factor (IF), recognitionand transport of the IF-complexes by IF-Cbl receptors (IFCR) onCaco-2 monolayers and oral absorption of the Cbl-conjugates in the rat.
Results. All Cbl-peptides bound to IF and the IF-complexes wererecognized by IFCR receptors on Caco-2 monolayers. Binding wassaturable and could be inhibited by a 20-fold excess of IF-Cbl, but notof Non-intrinsic Factor (NIF)-Cbl. Oral administration of these ligandsto rats resulted in absorption of 53%, 45%, 42%, and 23% of theapplied radioactivity for Cbl, Cbl-LHRH, Cbl-Hex-DP3, and Cbl-DP3,respectively. Simultaneous administration of a >105-fold excess ofunlabeled Cbl reduced uptake of all compounds to <4%. Tissuedistribution and elimination of the metabolically stable Cbl-conjugates werecomparable to Cbl.
Conclusions. The endogenous Cbl uptake pathway can be exploitedfor oral peptide delivery as indicated by the specific and high (40–45%)uptake of metabolically stable Cbl-coupled octapeptides.Deceased 相似文献