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91.
Gottfried ON Rovit RL Popp AJ Kraus KL Simon AS Couldwell WT 《Journal of neurosurgery》2005,102(2):202-208
OBJECT: The purpose of this study was to evaluate the US neurosurgery workforce by reviewing journal recruitment advertisements published during the past 10 years. METHODS: The number of available academic and private neurosurgical staff positions was determined based on recruitment advertisements in the Journal of Neurosurgery and Neurosurgery for the 10-year period from 1994 to 2003. Advertisements were evaluated for practice venue, subspecialization, and location. The numbers of active neurosurgeons and graduating residents also were reviewed. The number of advertised neurosurgical positions increased from 141.6 +/- 38.2 per year from 1994 through 1998 to 282.4 +/- 13.6 per year from 1999 through 2003 (mean +/- standard deviation, p < 0.05). The mean number of academic positions increased from 50.6 +/- 11.1 to 95 +/- 17.5 (p < 0.05), and the mean number of private positions rose from 91 +/- 30.4 to 187.4 +/- 6.8 (p < 0.05). Subspecialty positions represented a mean of only 15.6 +/- 5% per year during the first time period and 18.8 +/- 3% per year in the second period (p = 0.22), and therefore the majority of positions advertised continued to be those for generalists. The number of practicing neurosurgeons declined after 1998, and by 2002 it was less than it had been in 1991. The numbers of incoming and matriculating residents during the study period were static. CONCLUSIONS: The number of recruitment advertisements for neurosurgeons during the last 5 years has increased significantly, concomitant with a severe decline in the number of active neurosurgeons and a static supply of residents. 相似文献
92.
Gottfried Schubert 《Parasitology research》1966,27(3):271-286
Zusammenfassung Ultradünnschnitte von Costia necatrix, an Fischepidermis haftend, wurden elektronenmikroskopisch untersucht und die Ultracytologie beschrieben.Der festgeheftete Parasit bildet am Hinterende einen verschmälerten Stiel aus, der in einer Haftscheibe endet. Unter der Zellmembran laufen Züge tubulärer Fibrillen, die in der Nähe der Haftscheibe die Oberfläche verlassen und zu deren Zentrum ziehen. Die Kontraktionsfähigkeit dieser Faserzüge wird diskutiert. An einer der beiden Geißeln fällt ein kurzer paraflagellarer Stab auf.
Costia besitzt ein ringförmig geschlossenes Kinetoplast-Mitochondrion, das Cristae mitochondriales und fadenförmige DNS aufweist. Die Bedeutung dieses Organells in Hinblick auf das allgemeine Auftreten von DNS in Mitochondrien wird diskutiert.Zur Nahrungsaufnahme dringt Costia mit fingerartigen Fortsätzen in die Wirtszelle ein und nimmt Teile von ihr auf.Auf Grund der ultracytologischen Merkmale wird vorgeschlagen Costia necatrix zur Familie Bodonidae, Protomonadinae zu stellen.
Summary Ultrathin sections of Costia necatrix sticking to fish epidermis were studied electronmicroscopically. The ultracytology of Costia is described.The attached parasite forms a narrowing stalk at its rear, ending with a sticking disc.Tubular fibrils lie below the cellular membrane. Near the sticking disc they leave the surface and run to the center of the disc. The contractibility of those fibers is discussed. Costia possesses a cinetoplast-mitochondrion displaying cristae mitochondriales and fibrillar DNA. Regarding the general occurrence of DNA in mitochondria the problem of the cinetoplast-mitochondrion is discussed.For feeding Costia protrudes with finger-like processes into the epidermal cell ingesting parts of it.Considering the ultracytology it is suggested to include Costia necatrix into the family Bodonidae, Protomonadinae.相似文献
93.
Zusammenfassung An Hand von 5 selbst beobachteten und 328 aus der Literatur zusammengestellten Adenolymphomen wird zur Pathogenese der Tumoren Stellung genommen. Während 4 der eigenen Geschwülste papillärcystische Adenolymphome vom TypusAlbrecht undArzt sind, ist der 5. ungewöhnlich und zeichnet sich durch Besonderheiten der Struktur, des Epithels und des Verhältnisses von lymphatischem Gewebe und Epithel aus. Seine Einordnung in die Gruppe der Adenolymphome wird begründet. Die Geschwülste werden morphologisch und biologisch charakterisiert und in Analogie zu den einfachen Sialadenomen in tubulöse, acinöse und Übergangsformen eingeteilt. Bezüglich ihrer formalen Genese wird angenommen, daß sie vom Speicheldrüsenparenchym der erwachsenen Drüse selbst oder von Drüsengewebe abstammen, das während der Entwicklung in lymphatisches Gewebe der Wangenregion eingeschlossen wurde. Die branchiogene Entstehung wird abgelehnt. 相似文献
94.
Margret S. Magid Martin Perlin Eugene L. Gottfried 《American journal of obstetrics and gynecology》1982,144(8):910-914
An unexpected increase in erythrocyte osmotic fragility during pregnancy in two healthy women prompted a study of the effects of pregnancy on osmotic fragility. The incubated glycerol lysis time, a rapid, sensitive measure of osmotic fragility, was determined in 100 pregnant women and 50 nonpregnant control subjects. Twenty-two of the pregnant women (22%) showed abnormal results when compared to normal nonpregnant women (p < 0.0005). Increased erythrocyte fragility was observed primarily in the last trimester of pregnancy. Twenty-one of 65 women in the last trimester (32.3%) had abnormal incubated glycerol lysis time values, but only one of 34 (2.9%) showed increased fragility during early pregnancy. Physiologic shifts in erythrocyte osmotic fragility may create a problem in the diagnosis of hereditary spherocytosis during the last trimester of pregnancy. 相似文献
95.
Heinzel A Bermpohl F Niese R Pfennig A Pascual-Leone A Schlaug G Northoff G 《Brain research. Cognitive brain research》2005,25(1):348-358
One of the major problems in affective neuroscience of healthy subjects as well as of patients with emotional dysfunctions is to disentangle emotional core functions and non-emotional processes. Emotional valence is considered an emotional key process. The present study employed a parametric functional magnetic resonance imaging (fMRI) study to address this question. Thirteen healthy volunteers were scanned during emotional stimulus processing (International Affective Picture System). The presented pictures covered the entire range of emotional valences. The fMRI data were consecutively subjected to a preliminary categorical (valence-independent) and a detailed parametric analysis, the latter using individual valence ratings as regressor. The parametric analysis revealed a linear valence-dependent modulation of the BOLD signal in the orbito- and dorsomedial prefrontal cortex (OMPFC, DMPFC), medial parietal cortex (MPC), and insula. In addition, we observed that emotional valence exerts its effects predominantly via modulation of signal decreases. We conclude that the psychological concept of emotional valence may be related to neural processing in cortical midline regions. 相似文献
96.
Doelken R Weigel S Schueler F Doelken G Beck JF 《Pediatric hematology and oncology》2005,22(8):699-703
The authors report on 2 boys, 11(1/2) and 13 years old, who received allogeneic stem cell transplantation (alloSCT) from their HLA-identical sibling after relapse of stage IV alveolar rhabdomyosarcoma. Both patients were transplanted in a non-remission status. After alloSCT both patients experienced disease progression at the primary tumor location sites and died due to the underlying disease 146 and 379 days after transplantation. The authors conclude that an alloSCT derived graft versus tumor effect might not be effective enough to overcome alveolar rhabdomyosarcoma when transplantation is carried out in a nonremission status. 相似文献
97.
Marculescu R Sodeck G Domanovits H Hobusch G Exner M Heinzl H Huber K Mannhalter C Minar E Wagner O Schillinger M 《Thrombosis and haemostasis》2005,94(3):646-650
Inflammation is a key factor in the pathogenesis of abdominal aortic aneurysms (AAA). Interleukin 1 (IL-1), a fundamental regulator of the inflammatory cascade, has been shown to be involved in this process. Several functional polymorphisms in the IL-1 gene cluster are known. In this matched case-control study, we investigated a potential association between six genetic variants in IL-1 and IL-1 receptor antagonist (IL-1 RN) with AAA. We enrolled 405 individuals, 135 consecutive patients with AAA were individually age- and sex-matched to 270 patients with coronary artery disease (CAD).Traditional cardiovascular risk factors and IL-1 genotypes were determined, and the distribution of six single nucleotide polymorphisms were compared between patients and controls by multivariable conditional logistic regression analysis: IL-1A (-889) C>T, IL-1A (+4845) G>T, IL-1B (-511) C>T, IL-1B (-31) C>T, IL-1B (+3954) C>T and IL-1RN (+2018) C>T. IL-1A (-889) C>T and IL-1A (+4845) G>T (kappa 0.98,95% CI 0.96 to 1.00), and IL-1B (-511) C>T and IL-1B (-31) C>T (kappa 0.98, 95% CI 0.96 to 1.00) were closely linked, therefore IL-1A (-889) C>T and IL-1B (-31) C>T were not considered for further analyses. None of the 4 remaining polymorphisms showed a significant association with AAA: IL-1RN (+2018) C>T (p = 0.061), IL-1B (+3954) C>T (p = 0.51), IL-1B (-511) C>T (p = 0.61) and IL-1A (+4845) G>T (p = 0.81). No significant first-degree interactions between the genetic variants and AAA were detected. In conclusion,these six genetic variants in the interleukin- I gene cluster do not seem to play a clinically relevant role in the pathogenesis of AAA, although we cannot rule out the existence of higher degree gene-gene or gene-environment interactions. 相似文献
98.
Kremsner PG 《Lancet》2005,365(9469):1441-1443
99.
Schoellnast H Brader P Oberdabernig B Pisail B Deutschmann HA Fritz GA Schaffler G Tillich M 《Journal of computer assisted tomography》2005,29(5):582-587
OBJECTIVE: The purpose of this study was to assess the influence of the iodine flow rate on parenchymal and vascular enhancement during multiphasic abdominal multidetector-row computed tomography (MDCT). METHODS: Fifteen patients underwent MDCT at an iodine flow rate of 1.2 g/s as well as 1.6 g/s (group A, protocols 1 and 2), and 90 patients underwent MDCT at an iodine flow rate of 1.2 g/s (group B) or 1.6 g/s (group C). Measurements were performed for all groups in the liver, spleen, pancreas, portal vein, inferior vena cava, and abdominal aorta. RESULTS: Aortal and pancreatic enhancement during the arterial phase was significantly higher with the higher iodine flow rate. The mean difference in aortal enhancement was 60 Hounsfield units (HU) between protocols 1 and 2 of group A, and the mean difference was 70 HU between groups B and C. The mean difference in pancreatic enhancement was 10 HU between protocols 1 and 2 of group A and 17 HU between groups B and C. During the portal and hepatic venous phases, no significant difference in enhancement was observed. CONCLUSION: A high iodine flow rate in multiphasic abdominal MDCT improves enhancement of the aorta and the pancreas during the arterial phase but does not influence later phases. 相似文献
100.
The influence of three different cavity preparations on the marginal integrity of partial ceramic crowns (PCC) luted with four different luting systems was investigated in this in vitro study. PCC preparations were performed in 144 extracted human molars using one of the following preparation designs (n=48/preparation): A--Coverage of functional cusps/butt joint preparation; B--horizontal reduction of functional cusps and C--complete reduction of functional cusps/butt joint preparation. Non-functional cusps were not covered; mesial and distal proximal boxes were extended 1 mm below the cemento-enamel-junction. PCC were fabricated from Vita Mark II ceramic (Vita) with a Cerec 3 Unit (Sirona) and adhesively luted to the cavities using the following luting systems: (VL) Variolink II/Excite (Vivadent), (PA) Panavia F/ED Primer (Kuraray), (DY) Dyract/Prime & Bond NT (DeTrey/Dentsply) and (FU) Fuji Plus/GC Cavity Conditioner (GC). Samples were simultaneously exposed to thermocycling and mechanical loading (TC: 5000x8-55 degrees C, 30 seconds/cycle; ML: 500000x72.5N, 1.6Hz). Marginal adaptation was assessed by evaluating dye penetration on multiple sections by relating the actual penetration distance to the maximal length of the corresponding cavity wall (100%). Ceramic- and tooth-luting material interfaces were evaluated separately. The data were statistically analyzed with the Mann Whitney U-test and Wilcoxon Rank Sumtest. In general, no significant differences could be found between preparations A, B and C. The combination of preparation C and luting material PA showed a tendency for the lowest dye penetration values, especially within dentin (30%). Significant differences could be determined between luting materials: Composite luting materials PA (0%) and VL (1%) revealed less dye penetration than the compomer DY (6%) and resin-modified glass ionomer cement (RMGIC) FU (26%); use of RMGIC caused fractures of the restorations. The dentin/luting material interface showed the highest penetration values, ranging from 17% to 100%. In conclusion, with adhesively bonded partial ceramic crowns, the choice of luting material proved to be more relevant than preparation design under the limitations of this study. Margins below the cemento-enamel junction reveal significant loss of adhesion in spite of subsequent application of adhesive luting techniques. RMGIC cannot be recommended as a luting material for feldspathic PCC. 相似文献