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排序方式: 共有3088条查询结果,搜索用时 15 毫秒
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Uptake of Adriamycin in tumour and surrounding brain tissue in patients with malignant gliomas 总被引:1,自引:0,他引:1
H. von Holst E. Knochenhauer H. Blomgren V. P. Collins L. Ehn M. Lindquist G. Norén C. Peterson 《Acta neurochirurgica》1990,104(1-2):13-16
Summary Eight patients with malignant gliomas verified on CT scan, received an intravenous injection of 50 mg of Adriamycin R, 24 hours prior to surgical removal of the tumour. Peroperatively, both tumour and surrounding tissue specimens were obtained for determination of the tissue concentrations of Adriamycin and its reduced metabolite Adriamycinol. It was found that Adriamycin could be detected in tumour tissue from all patients. The concentration varied between 0,9 and 4,6 nmol/g tissue. In contrast, Adriamycin could only be detected in surrounding brain tissue from one patient.In anin vitro study a human malignant glioma cell line (U-251 MG) was exposed to various concentrations of Adriamycin for 24 hours. It was found that an intracellular drug concentration above 30 nmol/g cells caused a concentration dependent inhibition of cell growth. Thus, it is likely that the poor effect of Adriamycin on patients with malignant gliomas is due to an ineffective drug accumulation in the tumour tissue. 相似文献
3.
Dr. Peter Layer MD Jens Juul Holst Daniel Grandt Harald Goebell 《Digestive diseases and sciences》1995,40(5):1074-1082
There is evidence that the distal intestine participates in the regulation of gastric motor and secretory function. It was the aim of this study to examine in greater detail the effects of ileal nutrient exposure on human gastric acid secretion and to investigate potential intermediary mechanisms. Twelve normal subjects were intubated with an oroileal multilumen tube assembly for gastric, duodenal, and ileal perfusion of marker and test solutions, aspiration, and intestinal manometry. We studied ileal effects on gastric acid output in the unstimulated, interdigestive state (during early phase II,N=6), and during endogenous stimulation by intraduodenal essential amino acid perfusion,N=6) and on release of candidate humoral mediators, peptide YY (PYY) and glucagonlike peptide-1 (GLP-1), both known inhibitors of human gastric acid secretion. Compared with ileal saline perfusion, ileal carbohydrate (total caloric load: 60 kcal) decreased interdigestive gastric acid output by 64% (P<0.01), and endogenously stimulated output by 68%, respectively (P<0.005). Under all experimental conditions, ileal carbohydrate increased plasma GLP-1 by 80–100% (allP<0.005). Ileal lipid perfusion had similar inhibitory effects on gastric acid output and stimulatory effects on GLP-1 release as had ileal carbohydrate. By contrast, ileal perfusion with peptone had no or only weak effects on either acid output or plasma GLP-1. Plasma PYY concentrations and suppression of gastric secretion in response to ileal perfusions were not correlated. In humans, both interdigestive and endogenously stimulated gastric acid output are inhibited in response to intraileal carbohydrate or lipids, but not protein, Decreased acid output is associated with release of GLP-1, but not PYY. These findings support the hypothesis that the distal small intestine may participate in the late postprandial inhibitory regulation of gastric secretory function in humans and that GLP-1 may be an intermediary factor. 相似文献
4.
Neopterin concentrations, reflecting T-cell macrophage activation, were analyzed in serum and cerebrospinal fluid (CSF) obtained from 14 patients with subarachnoid hemorrhage (SAH). Neopterin concentrations were elevated in both the serum and CSF. The increase in neopterin concentrations was most marked in the CSF, rising from Days 1 to 3 through Days 6 to 9; levels were highest in patient suffering from delayed cerebral ischemia. The present data were interpreted as signs of an ongoing T cell activation both systemically and in the CSF compartment following SAH. 相似文献
5.
Flemming M. Nilsson Birgitte L. Hansen Christian Büchel Wagner F. Gattaz Jes Gerlach 《European archives of psychiatry and clinical neuroscience》1996,246(2):71-77
Digital movment analysis (DMA) is a new instrumental approach to assessing oral tardive dyskinesia (TD) by means of digital image processing of a video signal, tracking five paper dots placed around the patient's mouth. A total of 40 schizophrenic patients, 30 with and 10 without TD, were examined twice (with a 3-month interval) with this new device. The patients were further examined with two TD rating scales: the St. Hans Rating Scale for extrapyramidal syndromes (SHRS) and the Abnormal Involuntary Movement Scale (AIMS).The schizophrenic patients accepted the instrumental assessment without any anxiety or resistance. The internal relibility of the apparatus was high, with correlation coefficients of 0.80–0.99. The DMA TD values correlated with the SHRS and AIMS scores with correlation coefficients of 0.48–0.73 indicating an acceptable, although not strong, concurrent validity. Fluctuations occurred from the first to the second examination independent of medication. For these fluctuations no correlation was found between DMA values and rating scores. Finally, the DMA device was able to detect perioral tremor as a sign of parkinsonism.It has been concluded that DMA is a useful supplement to classical TD rating, although further validity evaluation is warranted. 相似文献
6.
BACKGROUND: Recalcitrant gingival erythematous lichen planus/lichenoid lesions comprise a considerable therapeutic problem. The objective of this study was to evaluate the therapeutic effect of grafting keratinized oral palatal mucosa to the sites of gingival lichen. METHODS: In 12 patients 20 grafts were transplanted to buccal gingival lesions. Mean age of the patients was 59.8 +/- 7.1 years (range 46-71 years). The mean observation time was 32 +/- 32.7 months (range 5-97 months). RESULTS: On a 4-point clinical grade scale (0-3), 12 (60%) transplants showed complete healing grade 3, six (30%) grade 2 and two (10%) grade 1. CONCLUSIONS: Using oral mucosal grafts from the palatal mucosa for the treatment of recalcitrant erythematous gingival lichen planus/lichenoid lesions seems to be a promising treatment modality. 相似文献
7.
Hypothesis: Pathogenesis of postmenopausal hot flush 总被引:1,自引:0,他引:1
The pathogenesis of postmenopausal hot flush is still poorly understood. A hypothesis is presented where the perimenopausal decline in circulating estrogen levels may increase central norepinephrine and LH-RH secretion and produce a downward setting of the central thermostat resulting in a hot flush. 相似文献
8.
9.
Dual blockade of the renin-angiotensin system in type 1 patients with diabetic nephropathy. 总被引:7,自引:0,他引:7
Peter Jacobsen Steen Andersen Kasper Rossing Birgitte V Hansen Hans-Henrik Parving 《Nephrology, dialysis, transplantation》2002,17(6):1019-1024
BACKGROUND: Albuminuria and hypertension are predictors of poor renal and cardiovascular outcome in patients with diabetes. Approximately 30% of type 1 patients with diabetic nephropathy (DN) have albuminuria >1 g/day, and blood pressure >135 and/or >85 mmHg despite antihypertensive therapy with recommended doses of ACE inhibitor (ACEI) and diuretics. We tested the effect of dual blockade of the renin-angiotensin system (RAS) in these patients. METHODS: We performed a randomised double blind crossover trial with 2 months treatment with Irbesartan 300 mg o.d. and placebo added on top of previous antihypertensive treatment. We included 21 type 1 patients with DN responding insufficiently to ACEI and diuretics, as defined above. At the end of each treatment period, albuminuria, 24-h blood pressure and glomerular filtration rate (GFR) were measured. RESULTS: Addition of 300 mg Irbesartan to the patients' usual antihypertensive therapy induced a mean reduction in albuminuria of 37% (95% CI 20-49, P<0.001); from 1574 mg/24 h (95% CI 1162-2132) to 996 mg/24 h (95% CI 699-1419), a reduction in 24-h blood pressure of 8 mmHg systolic (95% CI -2 to 18) and 5 mmHg diastolic (95% CI 1-9) (P=0.11 and 0.01, respectively) (from placebo, mean (SE) 146 (4)/80 (2) mmHg). GFR remained unchanged. Serum potassium increased (mean 4.3 to 4.6 mmol/l, P=0.02). Intervention to reduce serum potassium was needed in two patients with GFR <35 ml/min/1.73 m(2). Otherwise the dual blockade with Irbesartan was safe and well tolerated. CONCLUSIONS: Dual blockade of the RAS may offer additional renal and cardiovascular protection in type 1 patients with DN responding insufficiently to conventional antihypertensive therapy, including recommended doses of ACEI and diuretics. 相似文献
10.
A. T. Fisk M. Holst K. A. Hobson J. Duffe J. Moisey R. J. Norstrom 《Archives of environmental contamination and toxicology》2002,42(1):118-126
To examine the influence of diet and age on organochlorine contaminant (OC) concentrations in two closely related ringed seal
(Phoca hispida) populations enantiomeric fractions (EFs) of chiral contaminants and stable isotopes of nitrogen (δ15N) and carbon (δ13C) were measured along with OCs in ringed seals collected from the east and west side of the Northwater Polynya. Seals from
these two locations were feeding at the same trophic level based on δ15N values in muscle but had slightly different sources of carbon based on δ13C measurements in muscle. After removing the influence of age, sex, and blubber thickness, OC concentrations did not vary
between ringed seals from the east and west side of the polynya. ΣPCB, ΣDDT, and Σchlordane were found to increase with age
for both male and female seals. The inclusion of older (>20 years) female seals, which may have a reduced reproductive effort,
may influence the relationships in females. Stable isotopes failed to describe OC concentrations in ringed seals suggesting
that diet was not a major factor in variation of OC concentrations within this ringed seal population. Cis- and trans-chlordane, oxychlordane, and heptachlor epoxide were all nonracemic in the ringed seal blubber but did not vary with age,
sex, or collection site. α-HCH appeared racemic (enantiomeric fraction = 0.50 ± 0.01) in the seals, although this EF is different
than those previously observed in their prey species, and was found to vary significantly with age. EF values in the ringed
seals varied considerably from other Arctic marine mammals and seabirds, providing addition evidence that the type(s) and
characteristic(s) of the enzymes involved in biotransformation of chiral OCs vary between these organisms.
Received: 11 April 2001/Accepted: 27 June 2001 相似文献