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1.
Polyploidization and centrosome hyperamplification in inflammatory bronchi   总被引:1,自引:0,他引:1  
OBJECTIVE AND DESIGN: Inflammatory and tumorous bronchi were screened in order to obtain new tumor relevant cytogenetic parameters. MATERIAL OR SUBJECTS: Bronchial cells of 32 patients were cultivated by standard cell culture procedures. METHODS: Tetraploidy and aneuploidy was determined by enumeration of chromosome 7 and 8 versus the number of centrosomes. The resulting data were correlated with histopathological data. RESULTS: Tetra- and aneuploidy of epithelial cells were detectable in 76% of tumor cell cultures, 75% of high grade inflammatory tissues and 40% of non- and low grade-inflammatory tissues. Additionally, we observed centrosome hyper-amplification and multipolar mitoses not only in the tumor but also in the early stages of inflammation. CONCLUSION: Inflammatory bronchi already show tumor-specific features and may consequently represent the preliminary genetic stage of cancer development in bronchi.  相似文献   
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一些保肝药物对原代培养大鼠肝细胞糖原合成功能的影响   总被引:1,自引:0,他引:1  
王惠芬  丛铮 《药学学报》1989,24(9):653-658
本文参照PO Seglen的方法并加以修改,建立了原代培养大鼠肝细胞糖原合成功能的测定体系。观察到联苯双酯既能使正常肝细胞合成糖原增加88%,又能保护肝细胞完全拮抗四氯化碳对其功能的损伤;银耳多糖能使四氯化碳对肝细胞糖原合成功能的损伤减轻57%;去甲斑蝥素10μg/ml能增加肝细胞糖原合成,浓度增加到100μg/ml时,此作用减弱,1000μg/ml则明显抑制糖原的合成,而且在10~100μg/ml浓度时,即能加强四氯化碳的损伤作用;100μg/ml CL1500和熊果酸二钠单独应用可增加肝细胞糖原合成,但与四氯化碳同时应用,反而加重对糖原合成的抑制作用。  相似文献   
4.
SM Erdmann  B Sachs  HF Merk 《Allergy》2004,59(3):358-358
  相似文献   
5.
The strong macrophage response occurring during Wallerian degeneration in the peripheral but not central nervous system has been implicated in tissue remodeling and growth factor production as key requirements for successful axonal regeneration. We have previously identified a population of CD8+ phagocytes in ischemic brain lesions that differed in its recruitment pattern from CD4+ macrophages/microglia found in other lesion paradigms. In the present study we show that crush injury to the sciatic nerve induced strong infiltration by CD8+ macrophages both at the crush site and into the degenerating distal nerve stump. At the crush site, CD8+ macrophages appeared within 24 hours whereas infiltration of the distal nerve parenchyma was delayed to the second week. CD8+ macrophages were ED1+ and CD11b+ but always MHC class II-. Most CD8+ macrophages coexpressed CD4 while a significant number of CD4+/CD8-macrophages was also present. Expression of the resident tissue macrophage marker ED2 was largely restricted to the CD4+/CD8- population. Following intraorbital crush injury to the optic nerve, infiltration of CD8+ macrophages was strictly confined to the crush site. Taken together, our study demonstrates considerable spatiotemporal diversity of CD8+ macrophage responses to axotomy in the peripheral and central nervous system that may have implications for the different extent of axonal regeneration observed in both systems.  相似文献   
6.
We have recently reported isolation of the gene responsible for X- linked Opitz G/BBB syndrome, a defect of midline development. MID1 is located on the distal short arm of the human X chromosome (Xp22. 3) and encodes a novel member of the B box family of zinc finger proteins. We have now cloned the murine homolog of MID1 and performed preliminary expression studies during development. Mid1 expression in undifferentiated cells in the central nervous, gastrointestinal and urogenital systems suggests that abnormal cell proliferation may underlie the defect in midline development characteristic of Opitz syndrome. We have also found that Mid1 is located within the mouse pseudoautosomal region (PAR) in Mus musculus , while it seems to be X- specific in Mus spretus. Therefore, Mid1 is likely to be a recent acquisition of the M. musculus PAR. Genetic and FISH analyses also demonstrated a high frequency of unequal crossovers in the murine PAR, creating spontaneous deletion/duplication events involving Mid1. These data provide evidence for the first time that genetic instability of the PAR may affect functionally important genes. In addition, we show that MID1 is the first example of a gene subject to X-inactivation in man while escaping it in mouse. These data contribute to a better understanding of the molecular content and evolution of the rodent PAR.   相似文献   
7.
Zusammenfassung Nach Darlegung technischer und ballistischer Einzelheiten über Handfeuerwaffen und eine klinische Einleitung wird über 20 eigene Fälle mit Schädelschußverletzungen berichtet. 16 Verletzungen gingen mit direkter Gehirnbeteiligung einher, 12 von denen verstarben. Es wird auf die Wichtigkeit der Kenntnis der Tatwaffen und des Schußkanalverlaufs im Röntgenbild verwiesen, und die besondere Bedeutung der Bewußtseinslage, der neurologischen Symptomatik und der Schocksituation zur prognostischen Bewertung dieser Verletzungen herausgestellt.
Summary After setting out technical and ballistic details of small arms and after a clinical introduction, a series of 20 personal cases with gun-shot wounds of the head are described. Sixteen patients had direct involvement of the brain, of whom 12 died. The importance of a knowledge of the weapon used and of the course of the missile as seen in the radiographs is referred to. It is demonstrated that in these patients the level of consciousness, the neurological symptoms and the degree of shock are of especial importance in assessing prognosis.

Resumen Después de un breve resumen de los detalles técnicos y balísticos de armas de fuego y tras una introduction clínica se analiza una serie de 20 casos personales de heridas craneales por arma de fuego. De 16 enfermos que tuvieron lesiones cerebrales 12 fallecieron. El autor insiste sobre la importancia del conocimiento del arma utilizada, así como del trayecto de la bala visto en las radiografías. En estos enfermos el nivel de conciencia, los signos neurológicos y el grado de shock tienen una gran importancia para el pronóstico.

Résumé Après un bref rappel des détails techniques et ballistiques des armes légères, et après une introduction clinique, une série de 20 cas personnels de blessures cranielles par coup de fusil est rapportée. Sur 16 malades qui ont eu des lésions cérébrales: 12 sont décédés. L'auteur insiste sur l'importance de la connaissance de l'arme utilisée et du trajet de la balle vu sur les clichés. Chez ces malades, le niveau de conscience, les signes neurologiques et le degré du choc ont une grande importance dans le pronostic.

Riassunto Vengono discussi venti casi di ferite craniche da arma da fuoco, 16 dei quali avevano una compromissione cerebrale. Di essi 12 sono morti. Viene praticamente discussa l'importanza della conoscenza della forza di penetrazione della pallottola nei radiogrammi e della localizzazione del canale di entrata e di uscita e della situazione neurologica e dello stato di shock per la prognosi di questi feriti.
  相似文献   
8.
BACKGROUND: To improve postoperative pulmonary reserve, we have employed parenchyma-sparing resections for central lung tumors irrespective of pulmonary function. The results of lobectomy, pneumonectomy, and sleeve resection were analyzed retrospectively. METHODS: From October 1995 to June 1999, 422 typical lung resections were performed for lung cancer. Of these, 301 were lobectomies (group I), 81 were sleeve resections (group II), and 40 were pneumonectomies (group III). RESULTS: Operative mortality was 2% in group I, 1.2% in group II, and 7.5% in group III (group I and II vs. group III, p<0.03). Mean time of intubation was 1.0+/-4.1 days in group I, 0.9+/-1.3 days in group II, and 3.6+/-11.2 days in group III (groups I and II vs. group III, p<0.01). The incidence of bronchial complications was 1.3% in group I, none in group II, and 7.5% in group III (group I and II vs group III, p<0.001). After 2 years, survival was 64% in group I, 61.9% in group II, and 56.1% in group III (p = NS). Freedom from local disease recurrence was 92.1% in group I, 95.7% in group II, and 90.9% in group III after 2 years (p = NS). CONCLUSIONS: Sleeve resection is a useful surgical option for the treatment of central lung tumors, thus avoiding pneumonectomy with its associated risks. Morbidity, early mortality, long-term survival, and recurrence of disease after sleeve resection are similar to those seen after lobectomy.  相似文献   
9.
<正>To the Editor:Ischemia-reperfusion injury following surgery and transplantation can lead to irreversible multiorgan failure.Intracellular calcium overload is associated to cellular death during ischemiareperfusion.A recently discovered heparin fragment (HF),trisulfated disaccharide (TD),that acts on sodium-calcium exchanger(NCX) decreasing intracellular Ca2+,showed effectiveness on protecting hepatocytes from ischemia-reperfusion injury [1],  相似文献   
10.
Average bark-to-bark resistance of the IML Resistograph PD400 (hereafter referred to as ‘Resi’) was found to provide strong linear correlations with the basic density of 12-mm-diameter increment cores taken from standing plantation eucalypt trees. Relationships between Resi values and approximately 2 000 cores (predominantly Eucalyptus globulus but some E. nitens) were examined across seven studies (representing samples from nine distinct sites) in Tasmania, Victoria and Western Australia. Custom-written software was developed to process the Resi traces to automatically perform a linear baseline correction of the trace, and extract:
  • over-bark and under-bark diameter

  • bark thickness

  • average resistance of the bark-to-bark (under-bark) trace

  • average resistance of the outer 50 mm on the entry and exit side of the traces.

Baseline correction was needed to counter the variable effects among trees of needle drag across the diameter, largely a function of tree diameter and wood density.

Individual traces were collected in less than 20 s tree?1. The sampling conditions of 150 cm min?1 speed of forward movement (feed speed) and 3 500 revolutions per minute (rpm) were identified as optimal for the plantation eucalypts studied. The relationship between different feed speeds and rpm were linear and coefficients determined to allow average Resi resistance to be converted to a common set of sampling conditions. A simple linear regression was identified in each study to define a slope and intercept to convert the Resi values to basic density and determine the variance between them. Resi traces from different studies were not always collected using the same instrument and this is believed to explain most of the between-study variance in slope and intercept.

Trace processing software was built into a web-based package that is available to make trace processing easy, with defined variables downloadable for use in routine plantation assessment. Users can change the default slope and intercept values to suit their individual instruments or species as required. Further work is required to fully define the effects of instrument, site and species on these relationships.

The IML Resistograph PD400 was found to be an accurate and quick (40–70 trees hour?1 person?1) infield tool for estimating diameter and wood density in standing trees. When combined with automated, web-based processing software the methodology is among the lowest cost options conceivable for wood density assessment of plantation eucalypts.  相似文献   
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