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排序方式: 共有999条查询结果,搜索用时 15 毫秒
1.
Nurse perceptions of the Nursing Delirium Screening Scale in two palliative care inpatient units: a focus group study
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2.
顺铂聚乳酸微球的药物释放特性及肝动脉栓塞研究 总被引:5,自引:0,他引:5
对顺铂聚乳酸微球进行了体外药物释放和家犬肝动脉栓塞研究。该微球粒径范围为50~200μm,平均粒径为115.76±35.94μm,顺铂含量为37.16%(W/W);体外药物释放机制符合Higuchi方程;肝动脉栓塞后8h,肝组织顺铂浓度高达21.55±12.18μg/g,明显高于肝动脉灌注顺铂组:3.16±0.09μg/g(P<0.05);肝动脉栓塞组的顺铂血浓峰值、各取血点浓度及曲线下面积AUC皆低于肝动脉灌注顺铂组。可望达到提高栓塞部位的药物疗效,降低全身毒副反应的作用。 相似文献
3.
Measurements were made of glutathione (GSH) levels, catalase activity and the oxidant sensitivity of the erythrocytes from
the koala (Phascolarctos cinereus) and the common brushtail possum (Trichosurus vulpecula). The oxidant sensitivity was tested by treating the haemolysates with either 0.55 him H2O2 or 1.4mm NaNO2. The erythrocytes of the koala had greater levels of GSH and catalase and yet were found to be more susceptible to oxidation
induced by both these oxidants. 相似文献
4.
The action of adrenaline upon the uterus of the guinea-pig and its modification by eserine 总被引:1,自引:0,他引:1
Agar WT 《The Journal of physiology》1940,98(4):492-502
5.
Eri Ogawa Yuichiro Otsubo Norihiro Taira Nihal S. Agar 《Comparative clinical pathology》2005,13(3):137-141
Uptake of dehydroascorbic acid (DHA) was studied in two types of dog erythrocytes with high GSH and normal GSH levels. Compared with ascorbic acid uptake, DHA produced a much greater ascorbic acid accumulation in dog erythrocytes. Both dog erythrocytes showed a concentration dependence of DHA uptake, and cellular ascorbic acid concentrations were significantly higher in high-GSH cells than in normal-GSH cells. Glucose and cytochalasin B inhibited DHA uptake. This suggests that DHA enters dog erythrocytes predominantly by the facilitated glucose transporter, particularly by the Glut 1 glucose transporter. The rate of glucose uptake was quite similar in the two types of cells. Compared with normal-GSH cells, high-GSH cells were more resistant to oxidative stress induced by high concentration of DHA. As a rapid entry of DHA inflicts on cells a heavy demand for GSH for its reduction to ascorbic acid, high-GSH cells containing a larger reserve of GSH have an advantage over normal-GSH cells in both ascorbic acid accumulation and resisting oxidative stress produced by DHA. 相似文献
6.
Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy. 相似文献
7.
Effects of Hypothermia on Blood Endogenous Endotoxin Levels During Cardiopulmonary Bypass 总被引:1,自引:0,他引:1
Hakan Gerçekoglu M.D. Ozhan Tarim M.D. † Ismail Agar M.D. †† Ahmet Korukçu M.D. Hasan Karabulut M.D. Hüseyin Soydemir M.D. Onur Sokullu M.D. Hüseyin Toklu M.D. Candan B. Johansson Ph.D. † Besim Yigiter M.D. Ercüment Kopman M.D. †† 《Journal of cardiac surgery》1997,12(4):223-227
A bstract Endotoxin activates white blood cells and complement and produces a spectrum of clinical syndromes ranging from fever to septic shock. Although production of endogenous endotoxemia during cardiopulmonary bypass (CPB) has recently been reported, the role of hypothermia on endotoxemia is not clear. In this study, we evaluated the effects of moderate (24–28°C) and mild (32–34°C) hypothermia on blood endotoxin levels. The study population consisted of 20 patients who underwent coronary artery bypass grafting (CABG) with CPB. Moderate systemic hypothermia was applied during aortic cross-clamping in ten patients (group 1) and mild hypothermia in the remaining ten patients (group 2). The mean rectal temperatures were 26.8 ± 1.2°C in group 1 and 33.8 ± 0.8°C in group 2. The blood samples for endotoxin level measurements were obtained before CPB, during aortic cross-clamping, immediately after the release of the cross-clamp, 20 minutes after the release of the cross-clamp, after CPB, and 2 hours postoperatively. There were no endotoxins in any of the samples before CPB, but it was detected after CPB in both groups. The endotoxin levels were significantly higher in group 1 than in group 2. The present study suggests that when hypothermia is the technique of choice, the deleterious effects of endotoxemia on patients with comorbidity must be considered. 相似文献
8.
Auditory evoked responses (AER) were obtained from Cz and Fz in 30 adults (14 male, 16 female) from 20-80 years old. Sound bursts (1000 Hz-200 msec) of four different intensities were used. Peak to trough amplitudes of P1N1 and N1P2 and latencies of P1, N1 and P2 peaks were measured with increasing stimulus intensity and slopes of amplitude - intensity and latency - intensity curves were analysed for assessment of an age effect. The main result is that the increase in P1N1 amplitude with increasing stimulus intensity is more pronounced in older persons. Previous studies have established a negative correlation between the augmenting-reducing responses and HVA levels in the CSF (with lower amounts of HVA in the CSF of "augmenters"). Decreased dopamine metabolism in old subjects could account for our results, so further studies should focus on patients with pathological dopamine deficiencies. 相似文献
9.
Y chromosome microdeletions, in azoospermic or near-azoospermic subjects, are located in the AZFc (DAZ) subregion 总被引:9,自引:2,他引:9
Submicroscopic deletions of the Y chromosome and polymorphisms of the
androgen receptor (AR) gene in the X chromosome have been observed in men
with defective spermatogenesis. To further define the subregions/genes in
the Y chromosome causing male infertility and its relationship to
polymorphisms of the AR polyglutamine tract, we screened the genomic DNA of
202 subfertile males and 101 healthy fertile controls of predominantly
Chinese ethnic origin. Y microdeletions were examined with 16
sequence-tagged site (STS) probes, including the RBM and DAZ genes,
spanning the AZFb and AZFc subregions of Yq11, and related to the size of
trinucleotide repeat encoding the AR polyglutamine tract. Y microdeletions
were detected and confirmed in three out of 44 (6.8%) of azoospermic and
three out of 86 (3.5%) severely oligozoospermic patients. No deletions were
detected in any of the patients with sperm counts of >0.5 x 10(6)/ml,
nor in any of the 101 fertile controls. All six affected patients had
almost contiguous Y microdeletions spanning the entire AZFc region
including the DAZ gene. The AZFb region, containing the RBM1 gene, was
intact in five of the six subjects. Y deletions were not found in those
with long AR polyglutamine tracts. Our study, the first in a Chinese
population, suggest a cause and effect relationship between Y
microdeletions in the AZFc region (possibly DAZ), and azoospermia or
near-azoospermia. Y microdeletions and long AR polyglutamine tracts appear
to be independent contributors to male infertility.
相似文献
10.
Catt SL; Sakkas D; Bizzaro D; Bianchi PG; Maxwell WM; Evans G 《Molecular human reproduction》1997,3(9):821-825
Controlling the sex of offspring by the separation of X and Y
chromosome-bearing spermatozoa using flow cytometry has been reported as a
clinical technique aiding prevention of X-linked diseases. Although this
technique has resulted in several hundred normal births in animals and at
least one human birth, there is still concern over its genetic safety due
to the involvement of two potentially mutagenic agents: UV light and the
fluorochrome dye, Hoechst 33342 (H33342). Human spermatozoa, particularly
those considered abnormal, may be more likely to suffer DNA damage
following exposure to mutagenic agents, compared with other mammalian
species. The stability of normal fresh and decondensed human spermatozoa
were examined after exposure to a range of levels of UV and H33342
staining, using an assay that detects endogenous nicks in the DNA of
spermatozoa. The stability of abnormal and normal, fresh and frozen-thawed
human spermatozoa was examined following UV laser, H33342 staining and flow
cytometry treatments utilizing the same assay. There was an increase in the
presence of endogenous nicks when spermatozoa were decondensed compared
with fresh spermatozoa. There was no increase in the incidence of nicks in
any group of spermatozoa after UV and fluorochrome exposure compared with
controls without exposure.
相似文献