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排序方式: 共有621条查询结果,搜索用时 31 毫秒
1.
2.
Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
相似文献
3.
Recombinant allergens promote expression of CD203c on basophils in sensitized individuals 总被引:4,自引:0,他引:4
Hauswirth AW Natter S Ghannadan M Majlesi Y Schernthaner GH Sperr WR Bühring HJ Valenta R Valent P 《The Journal of allergy and clinical immunology》2002,110(1):102-109
BACKGROUND: Traditionally, the diagnosis of type I allergies is based on clinical data, skin test results, and laboratory test results with allergen extracts. During the past few years, several attempts have been made to refine diagnostic assays in clinical allergy by introducing recombinant allergens and novel markers of IgE-dependent cell activation. OBJECTIVES: We have identified the ectoenzyme CD203c as a novel basophil antigen that is upregulated on IgE receptor cross-linkage. In this study we applied CD203c and a panel of recombinant allergens to establish a novel basophil test that allows for a reliable quantification of IgE-dependent responses at the effector cell level. METHODS: Patients allergic to birch (Bet v 1, n = 15; Bet v 2, n = 8) and grass (Phl p 1, n = 15; Phl p 2, n = 10; Phl p 5, n = 14) pollen allergens, as well as 10 nonallergic donors, were examined. Basophils were exposed to various concentrations of recombinant allergens for 15 minutes and then examined for expression of CD203c by means of flow cytometry. CD203c upregulation was correlated with the increase in CD63. RESULTS: Exposure to recombinant allergens resulted in a dose-dependent increase in expression of CD203c on peripheral blood basophils in sensitized individuals, whereas no increase was seen in healthy control subjects. The effects of the recombinant allergens on CD203c expression were also time dependent. There was a good correlation between allergen-induced upregulation of CD203c and upregulation of CD63 (R = 0.76). CONCLUSION: Flow cytometric quantitation of CD203c on blood basophils exposed to recombinant allergens is a useful approach to determine the allergic state in sensitized individuals and represents a basis for a sensitive novel allergy test. 相似文献
4.
Background
Correct diagnosis in psychiatry may be improved by novel diagnostic procedures. Computerized Decision Support Systems (CDSS) are suggested to be able to improve diagnostic procedures, but some studies indicate possible problems. Therefore, it could be important to investigate CDSS systems with regard to their feasibility to improve diagnostic procedures as well as to save time. 相似文献5.
Transgenic technology in farm animals--progress and perspectives 总被引:4,自引:0,他引:4
Wolf E Schernthaner W Zakhartchenko V Prelle K Stojkovic M Brem G 《Experimental physiology》2000,85(6):615-625
Current applications of gene transfer in farm animals include the improvement of product quality and quantity, disease resistance, the production of valuable proteins in the mammary gland or other organs, the genetic modification of pigs for xenotransplantation and the generation of new animal models in cases where rodent models are not sufficient for studying the problem under evaluation. Although DNA microinjection into pronuclei of zygotes from various farm animal species has happened since 1985, the efficiency of this method is low. Further drawbacks are related to the random integration process which may cause mosaicism, insertional mutations and varying expression due to position effects. Sperm-mediated gene transfer is not routinely established yet, although the mechanisms of binding and internalisation of DNA by sperm cells is becoming increasingly clearer. New protocols for the use of retroviral vectors to infect metaphase II oocytes which are subsequently fertilised resulted in efficient production of transgenic cattle. In spite of extensive efforts to establish pluripotent stem cells from farm animal species, no germ-line competent cells have been reported in mammalian species other than mouse so far. However, recent success in cloning sheep, cattle, goats and pigs from cultured cells provides an alternative route for efficient and targeted genetic modifications of farm animals. 相似文献
6.
Natural killer cell activity and antibody-dependent cellular cytotoxicity in patients under various immunosuppressive regimens 总被引:3,自引:0,他引:3
C Müller G Schernthaner J Kovarik W Kalinowska C C Zielinski 《Clinical immunology and immunopathology》1987,44(1):12-19
The influence of various modes of immunosuppression using cyclosporin A (CyA), corticosteroids (Cort), azathioprine (AZA), and antithymocyte globulin (ATG) alone or in combination with each other upon natural killer (NK) cell activity and antibody-dependent cellular cytotoxicity (ADCC) was assessed. CyA given alone did not influence either NK or ADCC activity; in contrast, the administration of Cort resulted in a significant decline (P less than 0.01) of ADCC but not of NK activity (P greater than 0.1). The combination of the two drugs led to a significant impairment of NK activity (P less than 0.01). The combination of AZA and Cort was found to produce an even more pronounced reduction in NK activity compared to both healthy controls (P less than 0.001) as well as patients from the CyA + Cort group (P less than 0.001). A similar decrease was found also after the addition of ATG to CyA + Cort (P less than 0.001, compared both with patients on CyA + Cort and with controls). In these instances, ADCC showed an overall similar pattern. We conclude that the administration of either CyA or Cort does not influence NK activity, while the combination of CyA with Cort and of AZA with Cort leads to a decrease in both NK and ADCC activities. The monotherapy with Cort only leads to a reduction of ADCC. These findings may explain the higher incidence of malignancies in patients undergoing combined immunosuppressive treatment. 相似文献
7.
Cystic hypersecretory carcinoma (CHC) is a rare variant of intraductal carcinoma. A CHC in a 50-year-old woman was excised and processed for light and electron microscopy and immunohistochemistry. The tumor had a marked cystic appearance. The walls of the cysts consisted of epithelial and myoepithelial cells and a well-developed basement membrane. The epithelial cells contained well-developed rough-surfaced endoplasmatic reticulum and Golgi apparatus. Secretory granules were not detected, with the exception of a few mucus-producing cells. The secretion was predominantly homogenous, reminiscent of thyroid colloid, and demonstrated distinct PAS positivity. The cells displayed a strong labeling with epithelial membrane antigen (EMA) and EMA-positive structures were observed within the intraluminal secretion, too. Some of these were stained by alcian blue. In addition, the colloid-like material was admixed with mucus showing a filamentous internal structure and lipid droplets resulting in some heterogenity of the secretion. Intraductal micropapillary proliferation in some of the cysts and adjacent nondistended ducts was a further defining feature of the tumor. Steroid hormone receptor and Ki-67 proliferation marker immuno his Tochemistry showed scattered positivity among the tumor cells. These results are in agreement with previous observations and further clarify the nature of this low-grade in situ cancer. 相似文献
8.
Schernthaner GH Spanblöchl E Sperr WR Sillaber C Semper H Jurecka W Hagen W Wolff K Chott A Lechner K Valent P 《Annals of hematology》2000,79(12):660-666
Interferon (IFN)-α, a known inhibitor of myelopoiesis, is increasingly used to treat patients with systemic mastocytosis (SM). However, the
mechanisms of IFN-α effects on mast cell (MC) growth remain unknown, and the treatment responses may be variable. In the present study, factor-dependent
ex vivo differentiation of MCs from peripheral blood mononuclear cells (PBMNCs) was analyzed in a patient with SM treated
with IFN-α2b (3 million U/day). The patient exhibited an extensive MC infiltration in his bone marrow (BM) and increasing serum total
tryptase levels (spiking to >1400 ng/ml). PBMNCs were collected before and during IFN-α2b treatment and cultured in the presence or absence of stem cell factor (SCF, 100 ng/ml) for 42 days. In the absence of SCF,
no MC growth was detectable. However, in the presence of SCF, MC containing tryptase appeared in the cultures. Treatment with
IFN-α2b resulted in a time-dependent decrease in SCF-inducible formation of MCs from PB progenitor cells in vitro. Also, during
IFN-α2b treatment, blood histamine concentrations decreased. Serum total tryptase levels initially increased despite IFN-α2b treatment. However, after a latency period of a few months, tryptase concentrations declined and then reached a plateau.
In healthy individuals, the SCF-induced in vitro growth of MCs from their progenitor cells was also inhibitable by the addition
of IFN-α2b. In summary, our data show that IFN-α2b can exhibit inhibitory effects on factor-dependent growth of MC progenitor cells. However, it still remains open which
of the patients with mastocytosis can benefit from long-term IFN-α treatment.
Received: 19 January 2000 / Accepted: 17 April 2000 相似文献
9.
Schernthaner G 《Atherosclerosis. Supplements》2005,6(3):3-10
Cardiovascular disease is responsible for a large proportion of morbidity and mortality in people with type 2 diabetes, who typically have a clustering of risk factors for coronary heart disease (CHD), including dyslipidaemia. Intensive single-factor interventions to lower blood glucose have not eliminated the increased risk of adverse cardiovascular outcomes in patients with diabetes. In comparison, multifactorial interventions, which include normalizing blood lipids with statins, appear to be more effective in reducing CHD. However, risk reductions in patients with type 2 diabetes are often no better than those seen in people without diabetes, despite the much greater baseline risk in the former group. High-density lipoprotein cholesterol (HDL-C) is an independent risk factor for CHD, but is only minimally improved by statin therapy. Additional interventions aimed at increasing HDL-C can further reduce cardiovascular morbidity and mortality in patients with type 2 diabetes. However, use of fibrates in combination with statins may pose an unacceptable risk of myopathy. Therefore, other strategies for combination therapy are needed to normalize lipids in patients with type 2 diabetes or metabolic syndrome. 相似文献
10.
Holzäpfel A Festa A Stacher-Janotta G Bergmann H Shnawa N Brannath W Schernthaner G Stacher G 《Diabetologia》1999,42(12):1410-1412
Aims/hypothesis. Hyperglycaemia that is induced short-term slows gastric emptying in healthy subjects and patients with diabetes mellitus. Little information is available on the impact of longer-lasting, naturally occurring blood glucose increases and their reduction to euglycaemic values. We studied the relation between gastric emptying and pre-prandial and postprandial blood glucose concentrations in patients with Type II (non-insulin-dependent) diabetes mellitus and secondary failure to respond to oral hypoglycaemic treatment (a) before readjusting hypoglycaemic therapy and (b) 1 week thereafter.¶Methods. We studied 9 female and 1 male patient (age 60–78 years, BMI 21.9–32.5 kg/m2, diabetes duration 3–33 years, HbA1 c 8.8–13.2 %). Gastric emptying of a radiolabelled semisolid 1168 kJ meal was recorded scintigraphically.¶Results. Blood glucose concentration pre-prandial and postprandial was considerably lower subsequent to than before therapy readjustment in all patients (fasting, 7.9 mmol/l ± 1.5 SD vs 11.7 ± 1.7 mmol/l; 60 min postprandial, 11.7 ± 2.0 vs 15.4 ± 2.2 mmol/l). By contrast, gastric emptying was unchanged (residual radioactivity in stomach 50 min postprandial 65.7 ± 14.1 % vs 66.5 ± 12.9 %). There was no relation between emptying and either fasting blood glucose concentration or its postprandial increase.¶Conclusion/interpretation. The data do not support a major impact of actual, longer-lasting, naturally occurring blood glucose concentrations upon the rate of gastric emptying in patients with Type II diabetes. [Diabetologia (1999) 42: 1410–1412] 相似文献