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1.
Clonal T cells have been demonstrated in skin lesions of all stages of cutaneous T-cell lymphomas (CTCLs). However, there are conflicting data regarding the CTCL stage at which dissemination of clonal cells into peripheral blood occurs. Although the multifocal occurrence of cutaneous CTCL lesions and T-cell recirculation suggest an early appearance of neoplastic cells in the blood, circulating clonal T cells have only been detected in advanced stages. We investigated their occurrence by a highly sensitive polymerase chain reaction (PCR) assay amplifying T-cell receptor gamma rearrangements and subsequent heteroduplex temperature gradient gel electrophoresis (HD-TGGE) of the amplification products. Circulating clonal T cells were found in 26 of 45 patients with mycosis fungoides (MF), six of seven with Sezary's syndrome (SS), 10 of 13 pleomorphic CTCLs, and three of four unclassified CTCLs. Corresponding skin specimens carried clonal T cells in 29 of 40 MF, three of four SS, 12 of 12 pleomorphic, and two of two unclassified CTCL patients. Except for the blood specimen of a psoriatic patient, all samples of 60 controls (psoriasis vulgaris, atopic dermatitis, and healthy volunteers) revealed polyclonal amplification products. In 30 of 32 CTCL patients carrying a clonal rearrangement in blood and skin, identity of both clones was indicated by HD-TGGE and confirmed by sequencing six of these cases. We found an unexpected high frequency of identical clonal T cells in peripheral blood and skin of CTCL patients, including early stages of MF. This supports the concept of an early systemic disease in CTCL and raises new questions concerning the pathogenesis.  相似文献   
2.
The severity of pulmonary fibrosis is the main prognostic factor for survival of patients with interstitial lung diseases (ILD). Unfortunately, lung biopsy, which is the best method to assess fibrosis quantitatively, is done only once during the evolution of the disease. In this study we analyzed the relationship between the degree of fibrosis and the exponential constant k, derived from the lung pressure-volume curve (LPVC) in 33 patients with chronic ILD, 19 with pigeon breeder's disease (PBD), and 14 with idiopathic pulmonary fibrosis (IPF). Pulmonary function tests, including the LPVC, were obtained before biopsy. A semiquantitative histologic assessment of the severity of fibrosis was performed on lung tissues. All patients showed a decrease of total lung capacity, residual volume, compliance, and Pao2. The mean value of the constant k was 0.08 +/- 0.06. When expressed as a percent of normal values, 25 patients exhibited values of k lower than 70% of predicted; of the remaining 8 patients whose values were above 70% of predicted, 7 had PBD and only one IPF. On morphologic analysis, 19 patients displayed more than 50% fibrosis. No significant correlations were found between the extent of the lesion or severity of lung fibrosis and the conventional pulmonary function tests. By contrast, a moderate but significant correlation was found between k and the severity of lung fibrosis (r = -0.38, p < 0.05). These findings show that the shape of the LPVC, represented by the constant k, predicts the degree of lung fibrosis and could be useful in the clinical assessment and follow-up of patients with ILD.  相似文献   
3.
Zusammenfassung Fraktionierte Ammonsulfatfällung der Ghutaminsäure-Asparaginsäure-Amino-pherase aus einer Käsesuspension führte zu einem Transaminasekonzentrat, das durch Gefriertrocknung ein haltbares Trockenpräparat lieferte. Mit Hilfe einer ausgearbeiteten und eingehend geschilderten Methode zur qualitativen und quantitativen Ermittlung von Aminosäuren im Rundfilterchromatogramm wurden die im Ultrafiltrat einer Suspension aus durchgereiftem Sauermilchkäse vorkommenden Aminosäuren bestimmt. Valin,-Aminobuttersäure, Alanin, Glutaminsäure und Lysin wurden reichlich, Phenylalanin, Methionin, Tryptophan,-Aminobuttersäure, Tyrosin, Threonin und Serin in nur geringen Mengen gefunden. Cystin, Arginin und Oxyprolin konnten im untersuchten Konzentrationsbereich (unter 0,1%) nicht nachgewiesen werden. Durch quantitative Papierchromatographie wurde gezeigt, daß in einer Käsesuspension folgende Aminosäuren mit-Ketoglutarsäure umaminiert werden: Asparaginäure, Valin, Methionin,-Aminobuttersäure, Phenylalanin, Leucin und Isoleucin. Nicht völlig geklärt ist die Umaminierung von-Aminobuttersäure und Histidin. Keine Transaminierung erfahren Cystin, Lysin, Arginn,-Alanin und Prolin.Die vorliegenden Untersuchungen wurden gefördert durch eine Forschungsbeihilfe der Gesellschaft von Freunden der Technischen Universität Berlin-Charlottenburg; hierfür sei auch an dieser Stelle verbindlichst gedankt.  相似文献   
4.
Zusammenfassung In lagerndem Sauermilchquark, der ohne Reifungssalze aufbewahrt wurde und in reifendem Sauermilchkäse, der mit normalen Mengen an Reifungssalzen versetzt war, wurde die Aktivität und das Verhalten der Aminopherase untersucht, welche die Umaminierung zwischen Glutaminsäure und Asparaginsäure katalysiert. Das hier benutzte; eingehend beschriebene Verfahren der Fermentmessung beruht auf der Bestimmung von Brenztraubensäure, wie sie durch katalytische Decarboxylierung der Oxalessigsäure entsteht. Zu Beginn der Reifung war im Ausgangsquark keine Aminopherasenwirkung festzustellen. Sie trat jedoch schon in den ersten Stadien derReifung auf, erreichte nach etwa 24 Tagen einMaximum und blieb dann im wesentlichen konstant. Beide Untersuchungsreihen, also Ansätze mit und ohne Reifungssalzen, zeigten mengenmäßig und zeitlich gleichlaufende Aminopherasenaktivität. Die Aminopherase ist demnach nicht gemeinhin im Quark vorhanden. sie verdankt ihre Bildung ausschließlich der sich entwickelnden Käse-Mikroflora. Das Ferment wird innerhalb von 10–20 min zwischen 50–55° C zu rund 50%. zwischen 67 und 73° C vollständig inaktiviert. Das pH-Optimum liegt zwischen pH 7,0 und 7,6. Hinsichtlich der Hemmbarkeit durch verschiedene Inhibitoren verhält sich die Aminopherase recht ähnlich den in der Literatur beschriebenen Transaminasen. Die beträchtliche Hemmung durch Silber- sowie Quecksilbersalze, organische Quecksilberverbindungen und Chinone zeigt, daß auch das hier untersuchte Aminopherasensystem reifenden Sauermilchkäses als Thiolferment zu betrachten ist.Die Arbeit wurde gefördert durch eine Forschungsbeihilfe der Senatoren für Kreditwesen und für Volksbildung, Hauptamt Wissenschaft und Forschung, Berlin. Hierfür sei auch an dieser Stelle verbindlichst gedankt  相似文献   
5.
BACKGROUND: To correlate the retinal ganglion cell pattern to visual acuity and visual field data in a patient with bilateral optic disc drusen, a quantitative clinicopathological study was carried out. METHODS: Both retinae of a patient with optic drusen were whole-mounted. Retinal ganglion cell counts were made using a sampling scheme covering the whole retina and compared to the findings in 10 normal retinae. Relative ganglion cell reduction in the drusen retinae was correlated to clinical data. RESULTS: The total retinal ganglion cell count was reduced from 1244858+/-98736 in normal retinae to 305319 on the right and 527571 on the left eye with optic disc drusen. Large ganglion cells had a better chance of survival. Parafoveal ganglion cell loss was 57% for the right and 36% for the left eye, while visual acuity was 0.8 and 1.0 respectively. The mean light sensitivity loss increased from the centre (6.2 dB) to paracentral (9.9 dB), mid-peripheral (13.7 dB) and outer peripheral (15.0 dB) retina, while ganglion cell losses were smallest in outer peripheral retina (21.9%), followed by central (53.0%), mid-peripheral (70.9%) and paracentral retina (87.7%). CONCLUSION: These data validate Frisén's theory on central retinal resolution and provide the structural basis for the clinical rule that low visual acuity should not be attributed to disc drusen. Automated light sense perimetry gives an inadequate picture of retinal damage caused by optic disc drusen.  相似文献   
6.
For healing of critically sized bone defects, biocompatible and angiogenesis supporting implants are favorable. Murine osteoblasts showed equal proliferation behavior on the polymers poly-ε-caprolactone (PCL) and poly-(3-hydroxybutyrate)/poly-(4-hydroxybutyrate) (P(3HB)/P(4HB)). As vitality was significantly better for PCL, it was chosen as a suitable coating material for further experiments. Titanium implants with 600 µm pore size were evaluated and found to be a good implant material for bone, as primary osteoblasts showed a vitality and proliferation onto the implants comparable to well bottom (WB). Pure porous titanium implants and PCL coated porous titanium implants were compared using Live Cell Imaging (LCI) with Green fluorescent protein (GFP)-osteoblasts. Cell count and cell covered area did not differ between the implants after seven days. To improve ingrowth of blood vessels into porous implants, proangiogenic factors like Vascular Endothelial Growth Factor (VEGF) and High Mobility Group Box 1 (HMGB1) were incorporated into PCL coated, porous titanium and magnesium implants. An angiogenesis assay was performed to establish an in vitro method for evaluating the impact of metallic implants on angiogenesis to reduce and refine animal experiments in future. Incorporated concentrations of proangiogenic factors were probably too low, as they did not lead to any effect. Magnesium implants did not yield evaluable results, as they led to pH increase and subsequent cell death.  相似文献   
7.
In the year from 1974 to 1992 members of the Technical University of Zittau investigated problems of analytical modelling in the field of tribology. Most of the questions and suggestions came from difficulties in the practice of technology. Therefore the application of general knowledge to different concrete situations was adopted as the governing principle for this research. Thus modelling and generalizing became the favoured means of investigation. First of all erosive blasting wear became of interest because damage in coal and energy plants were studied. Later on sliding wear developed as a phenomenon which could be described by stochastic fields surprisingly well. One-, two- and three-body abrasive wear patterns were handled. Also the effect of lubrication on mechanical contacts was included in this study. Eventually droplet impact erosion and erosion by cavitation were objects of investigation, the former because of its appearance in the last stages of steam turbines, and the latter because of similarities to droplet impact.  相似文献   
8.
To improve well-known titanium implants, pores can be used for increasing bone formation and close bone-implant interface. Selective Laser Melting (SLM) enables the production of any geometry and was used for implant production with 250-µm pore size. The used pore size supports vessel ingrowth, as bone formation is strongly dependent on fast vascularization. Additionally, proangiogenic factors promote implant vascularization. To functionalize the titanium with proangiogenic factors, polycaprolactone (PCL) coating can be used. The following proangiogenic factors were examined: vascular endothelial growth factor (VEGF), high mobility group box 1 (HMGB1) and chemokine (C-X-C motif) ligand 12 (CXCL12). As different surfaces lead to different cell reactions, titanium and PCL coating were compared. The growing into the porous titanium structure of primary osteoblasts was examined by cross sections. Primary osteoblasts seeded on the different surfaces were compared using Live Cell Imaging (LCI). Cross sections showed cells had proliferated, but not migrated after seven days. Although the cell count was lower on titanium PCL implants in LCI, the cell count and cell spreading area development showed promising results for titanium PCL implants. HMGB1 showed the highest migration capacity for stimulating the endothelial cell line. Future perspective would be the incorporation of HMGB1 into PCL polymer for the realization of a slow factor release.  相似文献   
9.
BACKGROUND: The utility of cytomegalovirus (CMV) urine cultures was checked in patients with HIV (a) to identify those at risk for CMV retinitis and (b) to guide clinical decisions on treatment and prophylaxis of CMV retinitis. METHODS: HIV infected patients were tested for CMVuria by shell vial cell cultures. The prevalence of CMVuria was related to CD4 count, HIV risk group, and time before and after diagnosis of CMV retinitis. RESULTS: A total of 639 shell vial cell cultures were obtained from 266 HIV infected ophthalmic patients. Only 4% of all patients with a CD4 count > 400 x 10(6)/l shed CMV in their urine compared with 42% with a CD4 count < or = 50 x 10(6)/l. Twenty three of 25 patients with CMV retinitis had a CD4 count < or = 50 x 10(6)/l. Among 130 patients with a CD4 count < or = 50 x 10(6)/l (a) those who were CMVuric had a nearly sevenfold risk (p < 0.0001) of developing CMV retinitis (35%) compared with those who did not shed CMV in their urine (5%), and (b) CMVuria and CMV retinitis were more frequent in homosexuals (58%/25%) than in intravenous drug users (23%/15%). More than 1 year before diagnosis of CMV retinitis 18% of patients were CMVuric compared with 83% of patients who were CMV culture positive in the last 3 months. CMVuria under virustatic maintenance therapy is associated with worsening of retinitis in two thirds of cases. CONCLUSION: Ophthalmic screening of patients with HIV should include those with a CD4 count < or = 50 x 10(6)/l and focus on the subgroup with additional CMVuria. Screening of other patients can be dropped without undue risk in order to spare AIDS patients unnecessary hospital visits. CMVuria as a single finding, however, does not justify antiviral prophylaxis of CMV retinitis.  相似文献   
10.
Degradable implant material for bone remodeling that corresponds to the physiological stability of bone has still not been developed. Promising degradable materials with good mechanical properties are magnesium and magnesium alloys. However, excessive gas production due to corrosion can lower the biocompatibility. In the present study we used the polymer coating polycaprolactone (PCL), intended to lower the corrosion rate of magnesium. Additionally, improvement of implant geometry can increase bone remodeling. Porous structures are known to support vessel ingrowth and thus increase osseointegration. With the selective laser melting (SLM) process, defined open porous structures can be created. Recently, highly reactive magnesium has also been processed by SLM. We performed studies with a flat magnesium layer and with porous magnesium implants coated with polymers. The SLM produced magnesium was compared with the titanium alloy TiAl6V4, as titanium is already established for the SLM-process. For testing the biocompatibility, we used primary murine osteoblasts. Results showed a reduced corrosion rate and good biocompatibility of the SLM produced magnesium with PCL coating.  相似文献   
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