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21.
We tested the hypothesis that nutritionally stunted children have impaired regulation of energy intake (EI), a factor that could help explain the increased risk of obesity associated with stunting in developing countries. A 3-d residency study was conducted in 56 prepubertal boys and girls aged 8-11 y from the shantytowns of Sao Paulo, Brazil. Twenty-seven of the subjects were stunted and 29 were not stunted; weight-for-height Z-scores were not significantly different between the groups. Parents of the two groups had equivalent heights and body mass indices. Measurements were made of voluntary EI from a self-selection menu, resting energy expenditure (REE) and body composition. In addition, a 753-kJ yogurt supplement was administered at breakfast on one study day (with an equal number of children receiving the supplement on each of the 3 study days) and its effect on daily EI assessed. There was no change in EI over time in either group (P: = 0.957), and no significant difference in EI between stunted and nonstunted children, even though the stunted children weighed 10% less. Energy intake per kilogram body weight was significantly higher in the stunted children (278 +/- 89 (SD), vs. 333 +/- 67 kJ/kg, P: < 0.05) and EI/REE was also significantly higher (1.91 +/- 0.34 vs. 1.68 +/- 0.38, P: < 0.05). However, the relationship between EI and body weight was not significantly influenced by stunting (P: = 0.12). There was no significant effect of the breakfast supplement on daily EI in either group although the absolute difference in EI between supplement and control days was greater in stunted than in nonstunted children (DeltaEI: +460 +/- 1574 vs. -103 +/- 1916 kJ/d, P: = 0.25). These data provide preliminary evidence consistent with the suggestion that stunted children tend to overeat opportunistically, but further studies are required to confirm these results in a larger study.  相似文献   
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In the present study, the risk of exposure to aflatoxin in infants fed breast milk and formula was investigated. For this purpose, aflatoxin B1 (AFB1) was determined in the serum of both breast-fed and formula-fed infants. Serum AFB1 positivity was significantly higher in the formula-feeding (F) group than the breast-feeding (B) group (42.8 vs 8.5%, P <0.01). The AFB, concentration in different commercial formulas was also determined. Aflatoxin B1 was found in seven of the eight newly opened packages of different brands of formula. The concentrations showed a statistically significant increase at the 30th day after opening the packages (P <0.01). Although AFB1 concentrations in the formulas were found to be within acceptable limits for most countries, still, its existence must be carefully evaluated because future influences of very small amounts of aflatoxin on the growing organism have not been fully elucidated. Therefore, it was again concluded that for infants, human milk is safer than commercial formulas because of the lower contamination risk of aflatoxin. Also, commercial formulas must be regularly examined by authorities for the possible risk of aflatoxin contamination.  相似文献   
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Gamete donation in assisted reproduction is an accepted treatment option for certain infertile couples. Traditionally, men donating spermatozoa have been paid a nominal fee, whilst women donating oocytes have not. The issue of payment for sperm donors has recently attracted attention following the Human Fertilisation and Embryology Authority's (HFEA) suggestion that such payment may be withdrawn. Prior to the final meeting of the HFEA working party which is examining this issue, here we report the results of a survey designed to solicit opinion on whether sperm donors should be paid, to identify social or other factors which influence this opinion, and to examine the influence of financial incentive on potential donors. We surveyed 717 individuals in three distinct groups: the general public, students (potential donors), and infertility patients (potential recipients). The majority of the potential donor group (students) was in favour of paying sperm donors, as were infertility patients. In contrast the general public was not. The opinion of the general public on this issue was influenced by their prior knowledge of whether donors were paid: those of the general public favouring the payment of sperm donors had a prior awareness that such payments were made. Although not in favour of paying sperm donors, the general public overwhelmingly approved of the use of donated spermatozoa for the treatment of infertile couples, and thought that ways should be sought to increase the availability of donor spermatozoa for the treatment of infertility and for research purposes. Within the potential donor group (students), the majority indicated that financial reward was an important factor which would influence their decision to donate spermatozoa. As the majority of both the potential recipients and potential donors feels that sperm donors should be paid, perhaps the views of these groups should carry significant weight when the decision whether or not to withdraw payment is taken. This is especially the case in view of the fact that the majority of the general public is in favour of the use of donated spermatozoa for the treatment of infertile couples.   相似文献   
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Our aim was to check for calcium channel maturation and regulation on newborn rats during breastfeeding by mothers treated with the L-type calcium channel blocker nifedipine. Contractions by KCl and radioligand binding techniques were used to verify if Ca(2+) channels are modified in rat vas deferens of 40-day old litters that were breastfed by mothers injected daily with nifedipine during nursery. Injections were applied in the beginning (1st until 8th day), middle (9th until 16th day), or end (17th until 24th day) of nursery, to verify the period of highest susceptibility of newborn to nifedipine receptor regulation. Contractile responses revealed that only after the middle period of treatment of mothers the maximal effects (E(max)) induced in pups by KCl were increased by about 35%, without changes of apparent affinity (pD(2)). Additionally, binding studies with [(3)H] Isradipine in cell membrane preparations showed a greater density (B(max)) of Ca(2+) channels by about 55%, without changes of affinity (K(d)). Changes were not detected after treatment of mothers in the beginning or end of breastfeeding. In addition, in vas deferens of 60-day old litters, the E(max) returned to control values, showing that changes were not persistent. Moreover, body and vas deferens weights and blood testosterone of newborn were never changed. The histology of mammary gland was similar for treated and control mothers, suggesting a stable milk production. It is concluded that nifedipine treatment of mothers, if made during the 9th to 16th day of lactation, produced a short lasting reversible up-regulation of L-type Ca(2+) channels.  相似文献   
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An 80‐year‐old man presented with an 8‐week history of painless swelling in the right lacrimal gland region with infero‐medial dystopia of the globe. The lesion was excised and histology confirmed an orbital plasmacytoma. Multiple myeloma screening was negative and a solitary extramedullary plasmacytoma arising from the lacrimal gland was diagnosed. The patient was subsequently treated with radiotherapy.  相似文献   
30.

Background:

The natural polyphenol myricetin induces cell cycle arrest and apoptosis in preclinical cancer models. We hypothesised that myricetin-derived flavonoids with enhanced redox properties, improved cell uptake and mitochondrial targeting might have increased potential as antitumour agents.

Methods:

We studied the effect of a second-generation flavonoid analogue Oncamex in a panel of seven breast cancer cell lines, applying western blotting, gene expression analysis, fluorescence microscopy and immunohistochemistry of xenograft tissue to investigate its mechanism of action.

Results:

Proliferation assays showed that Oncamex treatment for 8 h reduced cell viability and induced cytotoxicity and apoptosis, concomitant with increased caspase activation. Microarray analysis showed that Oncamex was associated with changes in the expression of genes controlling cell cycle and apoptosis. Fluorescence microscopy showed the compound''s mitochondrial targeting and reactive oxygen species-modulating properties, inducing superoxide production at concentrations associated with antiproliferative effects. A preliminary in vivo study in mice implanted with the MDA-MB-231 breast cancer xenograft showed that Oncamex inhibited tumour growth, reducing tissue viability and Ki-67 proliferation, with no signs of untoward effects on the animals.

Conclusions:

Oncamex is a novel flavonoid capable of specific mitochondrial delivery and redox modulation. It has shown antitumour activity in preclinical models of breast cancer, supporting the potential of this prototypic candidate for its continued development as an anticancer agent.  相似文献   
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