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排序方式: 共有1101条查询结果,搜索用时 93 毫秒
1.
Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
2.
L. P. W. J. v. d. Heuvel C. H. Schröder C. O. S. Savage D. Menzel K. J. M. Assmann L. A. H. Monnens J. H. Veerkamp 《Pediatric nephrology (Berlin, Germany)》1989,3(4):406-413
Two children with Alport's syndrome are described, who developed anti-glomerular basement membrane (GBM) antibody-mediated nephritis after renal transplantation. The reactivity of antibodies in their serum with collagenase-solubilized normal GBM was examined by SDS-PAGE with one- and two-dimensional immunoblotting. The specificity was compared with that of antibodies present in serum from a patient with Goodpasture's syndrome, and a mouse monoclonal antibody (MCA-P1), directed against the Goodpasture antigen. All reacted in a similar way with collagenase-solubilized GBM. Since abnormalities in the composition of the GBM are present in Alport's syndrome, it is proposed that differing antigen composition of GBM in the host compared with the donor kidney, together with transplant rejection, may have provoked the development of post-transplant anti-GBM antibodies. 相似文献
3.
4.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
5.
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses. 相似文献
6.
Helmut Schulte und Gerd Assmann 《Sozial- und Pr?ventivmedizin》1988,33(1):32-36
Zusammenfassung Die «Prospektive Cardiovascular Münster» (PROCAM)-Studie wird seit 1979 bei Betriebsangehörigen im Raum Westfalen durchgeführt. Bis zum Ende der Rekrutierungsphase (Jahresende 1985) haben 20060 Personen beiderlei Geschlechts von 17 bis 65 Jahren an der Untersuchung teilgenommen. Die Untersuchung zu Beginn der Beobachtungszeit umfasst eine Anamnese nach standardisiertem Fragebogen, die Messung von Blutdruck und anthropometrischen Grössen, ein EKG sowie eine Blutentnahme nach zwölfstündiger Nahrungskarenz.Bei einer Längsschnittauswertung von Männern im Alter von 40 bis 65 Jahren, die zu Beginn noch keinen Herzinfarkt oder Schlaganfall erlitten hatten und einheitlich vier Jahre nachbeobachtet wurden, traten 73 Herzinfarkte oder koronare Todesfälle innerhalb des Beobachtungszeitraumes auf, während 2681 Probanden ohne Herzinfarkt oder Schlaganfall den Zeitraum überlebten.Durch eine Hyper/Dyslipoproteinämie (Cholesterin > = 300 mg/dl oder Cholesterin und/oder Triglyzeride > = 200 mg/dl und gleichzeitig HDL-Cholesterin unter 35 mg/dl) sowie einer multiplen logistischen Funktion unter Berücksichtigung der Parameter Alter, HDL-Cholesterin, Cholesterin, systolischer Blutdruck sowie der ja-nein Merkmale Zigarettenrauchen, Diabetes melliutus, Herzinfarkt in der Familie und Angina pectoris gelang es, jeweils ein Risikokollektiv abzugrenzen, das bei einer Prävalenz von unter 20% über zwei Drittel aller Inzidenzen umfasste. Als bester prädiktiver Einzelparameter erwies sich das HDL-Cholesterin.
Results of the Prospective Cardiovascular Münster (PROCAM) study
Summary In the Prospective Cardiovascular Münster(PROCAM) study since 1979 employees have been examined for cardiovascular risk factors and held under observation for the onset of clinically significant signs of atherosclerosis (myocardial infarction, stroke, coronary death). Until the end of recruitment (end of 1985) 20060 male and female employees aged 17–65 from 52 industrial companies in Westfalia have participated. The voluntary examination at the start of the observation period includes a standardised questionnaire, a physical examination, blood pressure measurements and an ECG. Blood samples are taken after an overnight fast.The data presented here describe the longitudinal evaluation of initially healthy men aged 40 to 65 who had suffered no myocardial infarction or stroke before the examination. In an uniform follow-up period of four years 73 myocardial infarctions and coronary deaths were observed while 2681 men had survived without myocardial infarction or stroke.By far the best single parameter for establishing a risk group was HDL cholesterol. Using the characteristic hyper/dyslipoproteinemia which means cholesterol > = 300mg/dl or HDL cholesterol < 35mg/dl combined with cholesterol > = 200mg/dl and/or triglyceride > = 200 mg/dl or a multiple logistic function including age. cholesterol, HDL cholesterol, systolic blood pressure, cigarette smoking, diabetes mellitus, angina pectoris and a family history of myocardial infarction patients at high risk for coronary heart disease could be identified. More than two thirds of new events happened in each of these high risk subgroups, which comprise less than 20 percent of men under consideration each.
Résultats de l'étude prospective de Münster (PROCAM)
Résumé Dans cette étude, les employés de différentes entreprises de Westphalie ont été examinés: environ 20000 personnes des deux sexes, âgées de 17 à 65 ans ont été recrutées pour cette étude (jusqu'à la fin de 1985). L'observation porte sur une anamnèse standardisée, sur la mesure de la pression sanguine et de différentes valeurs anthropométriques, un ECG et un examen sanguin suivant 12 heures de jeûne. Les données présentées ici concernent l'évaluation de la cohorte des hommes en bonne santé, âgés de 40 à 65 ans, qui n'avaient eu aucun accident cardiovasculaire avant le premier examen. Durant une période de suivi uniforme de 4 ans, 73 infarctus ou décès ont été observés, alors que 2681 hommes ont survécu. Le meilleur paramètre prédicteur pour établir un groupe à risque est, de loin, le cholestérol HDL. En utilisant les caractéristiques de l'hyper/ dyslipoprotéinémie (cholestérol > 300 mg/dl ou cholestérol HDL < 35 mg/dl, combiné avec un cholestérol > 200 mg/dl ou/et des triglycérides > 200 mg/dl) et une fonction de régression logistique multiple prenant en compte l'âge, le cholestérol HDL, le cholestérol, la pression systolique, le tabagisme, le diabète sucré, l'anamnèse familiale de coronaropathies, il est possible de caractériser un groupe à risque élevé: deux tiers des événements cardiovasculaires surviennent dans ce groupe, alors qu'ils ne concernent que 20% de la population masculine observés.相似文献
7.
Comparison of antigenic targets involved in antibody-mediated membranous glomerulonephritis in the mouse and rat 总被引:3,自引:2,他引:3
K J Assmann P Ronco M M Tangelder W P Lange P Verroust R A Koene 《The American journal of pathology》1985,121(1):112-122
Membranous glomerulonephritis in the mouse can be induced by a single injection of an antiserum against homologous, pronase-digested, renal tubular antigens (TAPron). In indirect immunofluorescence studies on normal mouse and rat kidneys it has now been found that the antiserum reacts strongly with the visceral epithelia of the mouse in a homogeneous pattern, while a faint granular staining is seen in the rat glomerulus against a homogeneous background. After injection in rats, a classic passive Heymann nephritis could be induced. By immunoprecipitation of radiolabeled rat renal brush borders (BB) it could be shown that anti-TAPron antisera contain antibodies to 330-kd and 90-kd BB proteins expressed by rat glomeruli. With the use of two monoclonal antibodies specific for the 330- and 90-kd proteins the homogeneous binding observed in rat and mouse glomeruli could be related to the 90-kd antigen, whereas the coarse irregular staining observed in rat glomeruli was only related to the 330-kd antigen. Immunoglobulins eluted from glomeruli of rats bound to rat glomeruli and reacted only with the 330-kd protein. They did not bind to mouse glomeruli. Discrete localization in coated pits, multivesicular bodies, and endoplasmic reticulum of the visceral epithelia was seen in immunoelectron-microscopy. The results presented thus demonstrate that immune deposits induced in the rat by anti-TAPron antibodies are related to antibodies specific for the 330-kd antigen, ie, the classic Heymann antigen. By contrast, immune deposits observed in the mouse are related to antibodies specific for a 90-kd protein. 相似文献
8.
Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos 总被引:8,自引:2,他引:8
Yang HW; Hwang KJ; Kwon HC; Kim HS; Choi KW; Oh KS 《Human reproduction (Oxford, England)》1998,13(4):998-1002
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture
environment differs from in-vivo conditions in that the oxygen
concentration is higher, and in such conditions the mouse embryos show a
higher concentration of reactive oxygen species (ROS) in simple culture
media. ROS are believed to cause damage to cell membranes and DNA
fragmentation in somatic cells. This study was conducted to ascertain the
level of H2O2 concentration within embryos and the morphological features
of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31
fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was
obtained from the IVF-embryo transfer programme. The relative intensity of
H2O2 concentrations within embryos was measured using
2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence
imaging and DNA fragmentation was observed with transmission electron
microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations
were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/-
SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and
unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed
only in fragmented embryos, and was absent in non-fragmented embryos.
Electron microscopic findings confirmed apoptotic bodies and cytoplasmic
condensation in the fragmented blastomeres. We conclude that there is a
direct relationship between increased H2O2 concentration and apoptosis, and
that further studies should be undertaken to confirm these findings.
相似文献
9.
Defective peroxisomal catabolism of branched fatty acyl coenzyme A in mice lacking the sterol carrier protein-2/sterol carrier protein-x gene function 下载免费PDF全文
Udo Seedorf Martin Raabe Peter Ellinghaus Frank Kannenberg Manfred Fobker Thomas Engel Simone Denis Fred Wouters Karel W.A. Wirtz Ronald J.A. Wanders Nobuyo Maeda Gerd Assmann 《Genes & development》1998,12(8):1189-1201
Gene targeting in mice was used to investigate the unknown function of Scp2, encoding sterol carrier protein-2 (SCP2; a peroxisomal lipid carrier) and sterol carrier protein-x (SCPx; a fusion protein between SCP2 and a peroxisomal thiolase). Complete deficiency of SCP2 and SCPx was associated with marked alterations in gene expression, peroxisome proliferation, hypolipidemia, impaired body weight control, and neuropathy. Along with these abnormalities, catabolism of methyl-branched fatty acyl CoAs was impaired. The defect became evident from up to 10-fold accumulation of the tetramethyl-branched fatty acid phytanic acid in Scp2(−/−) mice. Further characterization supported that the gene disruption led to inefficient import of phytanoyl-CoA into peroxisomes and to defective thiolytic cleavage of 3-ketopristanoyl-CoA. These results corresponded to high-affinity binding of phytanoyl-CoA to the recombinant rat SCP2 protein, as well as high 3-ketopristanoyl-CoA thiolase activity of the recombinant rat SCPx protein. 相似文献
10.