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排序方式: 共有802条查询结果,搜索用时 15 毫秒
1.
Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
2.
3.
Naloxone administration following operant training of sucrose/water discrimination in the rat 总被引:2,自引:0,他引:2
E. O’Hare J. Cleary D. T. Weldon C. J. Billington A. S. Levine P. J. Bartz 《Psychopharmacology》1997,129(3):289-294
The suppression of food intake observed following naloxone administration has often been ascribed to palatability or taste.
Unfortunately, many confounds become apparent when attempts are made to isolate such factors in the investigation of ingestive
behaviors. In the present study, rats (two groups) were trained to discriminate either a 10% or 5% sucrose solution from water
(0.1 ml). These mildly food deprived subjects (95% of free-feeding weight) were trained to press the appropriate lever in
a two-lever operant chamber following sampling of sucrose or water; successful responding was reinforced by delivery of a
45 mg grain food pellet. Following random exposure to reduced sucrose concentrations tested under extinction, a sucrose concentration
gradient (1.0, 0.5, 0.1, 0.05, 0.01 and 0.005% sucrose solution) was established for both training groups under IP saline
administration. Data collected under IP saline were then compared to those collected following random IP naloxone administration
(3.0, 1.0, 0.3 and 0.1 mg/kg). No significant differences were observed between the sucrose concentration gradients obtained
under saline and those obtained under naloxone, suggesting that the anorectic effect of naloxone is not primarily determined
by discrimination of sweet taste.
Received: 4 September 1996 / Final version: 16 October 1996 相似文献
4.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
5.
The aetiology of weight loss in patients with Parkinson''s disease is likely to be multifactorial. We studied 15 patients with Parkinson''s disease and 15 age- and sex-matched controls and looked for evidence of malabsorption due to small bowel bacterial overgrowth or alteration of intestinal permeability. There was a marked increase in orocaecal transit time in the patients with Parkinson''s disease, although lactulose hydrogen breath testing did not show evidence of small bowel bacterial contamination. Intestinal permeability measured by the differential sugar absorption test was also deranged. There was reduced absorption of mannitol in patients with Parkinson''s disease while lactulose absorption was similar in both groups, suggesting decreased non-mediated uptake across the enterocyte brush border membrane in patients with Parkinson''s disease. 相似文献
6.
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
7.
AIMS: Previous studies investigating the link between infection with Borrelia burgdorferi and morphoea have produced conflicting results. Often, these studies have been undertaken in patients from different regions or countries, and using methods of varying sensitivity for detecting Borrelia burgdorferi infection. This study aimed to establish whether a relation could be demonstrated in the Highlands of Scotland, an area with endemic Lyme disease, with the use of a sensitive method for detecting the organism. METHODS: The study was performed on biopsies of lesional skin taken from 16 patients from the Highlands of Scotland with typical clinical features of morphoea. After histological confirmation of the diagnosis, a nested polymerase chain reaction (PCR) using primers to a unique conserved region of the Borrelia burgdorferi flagellin gene was performed on DNA extracts from each biopsy. A literature search was also performed for comparable studies. RESULTS: None of the 16 patients had documented clinical evidence of previous infection with B burgdorferi. DNA was successfully extracted from 14 of the 16 cases but all of these were negative using PCR for B burgdorferi specific DNA, despite successful amplification of appropriate positive controls in every test. The results were compared with those of other documented studies. CONCLUSIONS: Examination of the literature suggests that there is a strong geographical relation between B burgdorferi and morphoea. These results, in which no such association was found, indicate that morphoea may not be associated with the subspecies of B burgdorferi found in the Highlands of Scotland. 相似文献
8.
A scale for the assessment of object relations: reliability, validity, and factorial invariance 总被引:1,自引:0,他引:1
Factor analysis of the Bell Object Relations Inventory items produced four subscales interpreted to be underlying dimensions of object relations. Replication factor analysis confirmed the factor structure. Subscales had high internal consistency and were free of age, sex, or social desirability response bias. Subscales had low intercorrelations with Brief Psychiatric Rating Scale (BPRS) sum scores, Global Assessment Scale scores, and most BPRS symptoms. Subscales appear to represent common features of personality and to sample a domain that is distinct from symptomatology, but related to variations in psychopathology. Percentage of high scoring subjects and subscale mean values are compared for seven criterion groups. High scores were least frequent among community active adults and most frequent among borderlines. Selected findings from the group comparisons are discussed to illustrate the potential of the instrument for empirical examination of theoretical assumptions about the object relations ego function and its components. 相似文献
9.
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
10.
The lactic acid jet test has been proposed for incorporation in international standards for dental cements, since results correlate well with in vivo erosion. In the literature, jet test results have been reported on only six glass ionomer cements. This study examines three types of glass ionomer, restorative, luting and metal reinforced, twenty materials from six manufacturers. A wide range of erosion rates was found particularly for restorative cements. The hypotheses put forward by previous workers to explain differences in erosion rates found on their limited range of glass ionomers do not apply to the wider range that we tested. 相似文献