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1.
Opsahl Michael S.; Fitz Tony A.; Rexroad Caird E. Jr; Fritz Marc A. 《Human reproduction (Oxford, England)》1996,11(6):1250-1255
We examined the effects of enclomiphene and zuclomiphene, aloneand in combination with oestradiol, on basal and gonadotrophin-stimulatedprogesterone secretion by isolated subpopulations of both large(granulosa-lutein) and small (theca-lutein) ovine luteal cells.Isolated large and small luteal cells derived from intact, enucleatedovine corpora lutea were incubated for 48120 h with orwithout 22R-hydroxycholesterol or pregnenolone (2.5 µM)and a range of enclomiphene, zuclomiphene, and/or oestradiolconcentrations (3100 µM), both with and withoutovine Iuteinizing hormone (100 ng/ml). Spent media were assayedin duplicate for progesterone content by radioimmunoassay. Enclomiphene,zuclomiphene, and oestradiol exhibited equivalent dose-dependentinhibitory effects on basal and gonadotrophin-stimulated smalland large ovine luteal cell progesterone secretion under allsubstrate conditions. Both cell types became more sensitiveto clomiphene inhibition with increasing time in culture. Incombined treatments, the effects of oestradiol and either enclomipheneor zuclomiphene became additive in longer-term cultures andwere never antagonistic In this model system, (i) clomiphene,like oestradiol, appears to inhibit 3-hydroxysteroid dehy-drogenaseactivity, (ii) both stereoisomers act as oestrogen agonists,(iii) neither demonstrates any anti-oestrogenic properties,and (iv) both large and small luteal cells become more sensitiveto clomiphene inhibition with increasing duration of exposure. 相似文献
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Lihteh Wu 《Indian journal of ophthalmology》2015,63(5):394-398
Macular telangiectasia type 2 also known as idiopathic perifoveal telangiectasia and juxtafoveolar retinal telangiectasis type 2A is an acquired bilateral neurodegenerative macular disease that manifests itself during the fifth or sixth decades of life. It is characterized by minimal dilatation of the parafoveal capillaries with graying of the retinal area involved, a lack of lipid exudation, right-angled retinal venules, refractile deposits in the superficial retina, hyperplasia of the retinal pigment epithelium, foveal atrophy, and subretinal neovascularization (SRNV). Our understanding of the disease has paralleled advances in multimodality imaging of the fundus. Optical coherence tomography (OCT) images typically demonstrate the presence of intraretinal hyporeflective spaces that are usually not related to retinal thickening or fluorescein leakage. The typical fluorescein angiographic (FA) finding is a deep intraretinal hyperfluorescent staining in the temporal parafoveal area. With time, the staining may involve the whole parafoveal area but does not extend to the center of the fovea. Long-term prognosis for central vision is poor, because of the development of SRNV or macular atrophy. Its pathogenesis remains unclear but multimodality imaging with FA, spectral domain OCT, adaptive optics, confocal blue reflectance and short wave fundus autofluorescence implicate Müller cells and macular pigment. Currently, there is no known treatment for this condition. 相似文献
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Taylor C Wallace Jeffrey B Blumberg Elizabeth J Johnson Andrew Shao 《Advances in nutrition (Bethesda, Md.)》2015,6(1):1-4
In the United States, dietary reference intakes describe the relations between nutrient intakes and indicators of adequacy, prevention of disease, and avoidance of excessive intakes among healthy populations for essential nutrients but not dietary bioactive components (DBCs), whose absence from the diet is presumably not deleterious to health (i.e., does not cause a deficiency syndrome). An appropriate framework is needed for establishing recommended intakes for which public health messages and food labeling for DBCs can be derived, because their putative health benefits may not be readily defined in the context of nutritional essentiality. In addition, a myriad of factors make determining their intake and status and investigating their discrete contributions to health particularly challenging. Therefore, the ASN Dietary Bioactive Components Research Interest Section felt it worthwhile to convene a special “hot topic” session at the 2014 Experimental Biology meeting to discuss this issue and serve as a call for future scientific dialogue on establishing a framework for recommended intakes of DBCs. This session summary captures the discussions and presentations that transpired during this session. 相似文献
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Camila R Correa C-Y. Oliver Chen Giancarlo Aldini Helen Rasmussen Carlos F Ronchi Carolina Berchieri-Ronchi Soo-Muk Cho Jeffrey B Blumberg Kyung-Jin Yeum 《Nutrition Research And Practice》2014,8(5):550-557
BACKGROUND/OBJECTIVES
Angelica keiskei is a green leafy vegetable rich in plant pigment phytochemicals such as flavonoids and carotenoids. This study examined bioavailability of flavonoids and carotenoids in Angelica keiskei and the alteration of the antioxidant performance in vivo.SUBJECTS AND MATERIALS
Absorption kinetics of phytochemicals in Angelica keiskei were determined in healthy older adults (> 60 y, n = 5) and subjects with metabolic syndrome (n = 5). Subjects consumed 5 g dry Angelica keiskei powder encapsulated in gelatin capsules with a low flavonoid and carotenoid liquid meal. Plasma samples were collected at baseline, 0.5, 1, 2, 3, 4, 5, 6, 7, and 8 h. Samples were analyzed for flavonoids and carotenoids using HPLC systems with electrochemical and UV detection, respectively, and for total antioxidant performance by fluorometry.RESULTS
After ingestion of Angelica keiskei increases in plasma quercetin concentrations were observed at 1-3 and 6-8 hr in the healthy group and at all time points in the metabolic syndrome group compared to baseline (P < 0.05). Plasma lutein concentrations were significantly elevated in both the healthy and metabolic syndrome groups at 8 hr (P < 0.05). Significant increases in total antioxidant performance were also observed in both the healthy and the metabolic syndrome groups compared to baseline (P < 0.05).CONCLUSIONS
Findings of this study clearly demonstrate the bioavailability of phytonutrients of Angelica keiskei and their ability to increase antioxidant status in humans. 相似文献7.
Urological cancers, namely prostate, bladder, kidney, testicular, and penile cancers, are common conditions that constitute almost one-quarter of all malignant diseases in men. Urological cancers tend to affect older individuals, and their development is influenced by modifiable metabolic, behavioral, and environmental risk factors. Phytochemicals may have cancer-fighting properties and protect against cancer development, slow its spread, and reduce the risk of cancer deaths in humans. This paper aims to review the current literature in regard to the effects of carotenoids in reducing urological cancer risk. 相似文献
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There is a growing body of evidence which suggests that macular pigment (MP), which is entirely of dietary origin, protects against age-related maculopathy. We evaluated the effect of a daily 20 mg lutein ester (equivalent of 10 mg/day free lutein) supplement in patients with early age-related maculopathy (ARM), in terms of macular pigment optical density (MPOD) and plasma concentrations of lutein. MPOD was measured using a flicker photometric technique in seven ARM sufferers and six age-matched controls over a period of supplementation which lasted 18-20 weeks. Plasma lutein increased from a mean (SD) baseline concentration of 182 (127)ng ml(-1) to a peak of 1077 (165)ng ml(-1) in ARM patients, and from 152 (57) to 1110 (605)ng ml(-1) in control subjects. Mean MPOD had increased significantly from baseline of 0.24 to a peak of 0.31 in ARM sufferers. This mean increment of 0.07 was the same for the age-matched controls (baseline: 0.20; peak: 0.27). The augmentation of MP, and plasma concentrations of lutein, following supplementation in subjects with ARM provides the first evidence the disease is not associated with intestinal malabsorption of the relevant macular carotenoids, and that a diseased macula can accumulate and stabilise lutein and/or zeaxanthin. Furthermore, these results suggest that the beneficial effects of lutein supplementation, if any, may be extended to subjects with established ARM. 相似文献
9.
To test the hypothesis that increased serum levels of vascular endothelial growth factor (VEGF) in women with polycystic ovaries or the polycystic ovary syndrome (PCOS) result from excess release by ovarian granulosa cells.Prospective study.Academic research setting.Twenty women undergoing IVF treatment, of whom 10 had normal ovaries and 10 had polycystic ovaries.Human granulosa lutein cells were isolated from follicular fluid obtained on the day of oocyte retrieval. Release of VEGF was assessed after co-incubation of granulosa lutein cells with gonadotropins and insulin. Serum and follicular fluid concentrations of VEGF were measured.Release of VEGF from granulosa lutein cells and serum levels of VEGF.Incubation with human hCG, and luteinizing hormone increased release of VEGF into the culture medium. Insulin alone did not increase release of VEGF, but addition of insulin increased hCG-stimulated release of VEGF. Serum and follicular fluid VEGF concentrations and the amount VEGF released from granulosa lutein cells obtained from women with polycystic ovaries or PCOS and those who developed the ovarian hyperstimulation syndrome were greater than those from granulosa lutein cells obtained from women with normal ovaries and those who did not develop the ovarian hyperstimulation syndrome.The amount of VEGF released by granulosa lutein cells is gonadotropin dependent and is augmented by insulin. The increased circulating concentrations of VEGF in women with PCOS may not only be due to an increased number of actively secreting granulosa lutein cells but also due to increased secretory capacity of each granulosa cell. 相似文献
10.
Prospective study of serum retinol, β-carotene, β-cryptoxanthin, and lutein/zeaxanthin and esophageal and gastric cancers in China 总被引:1,自引:0,他引:1
Abnet CC Qiao YL Dawsey SM Buckman DW Yang CS Blot WJ Dong ZW Taylor PR Mark SD 《Cancer causes & control : CCC》2003,14(7):645-655
Objective: This study examined the relationship between pretrial serum concentrations of retinol, -carotene, -cryptoxanthin, and lutein/zeaxanthin and the subsequent risk of developing esophageal squamous cell carcinoma and gastric cardia or non-cardia adenocarcinoma in subjects selected from a randomized nutritional intervention trial in Linxian, China, a region with epidemic rates of esophageal and gastric cardia cancer. Methods: We used a stratified case–cohort design to select cohort members for inclusion in this study. In all we measured serum concentrations of the above vitamins in 590 esophageal, 395 gastric cardia, and 87 gastric non-cardia case subjects as well as in 1053 control subjects. Relative risks (RRs) were estimated using Cox proportional hazards models. Results: Median values in our cohort were low for serum retinol (33.6 g/dl), -carotene (4.3 g/dl), and -cryptoxanthin (3.5 g/dl) , but were high for lutein/zeaxanthin (40.0 g/dl). Gastric cardia cancer incidence fell 10% for each quartile increase in serum retinol (RR = 0.90, 95% CI = 0.83–0.99). For esophageal cancer, an inverse association with retinol levels was found only in male non-smokers (RR = 0.79 per quartile increase, 95% CI = 0.63–0.99). For gastric non-cardia cancer, an inverse association was limited to subjects 50 years old or younger (RR = 0.58 per quartile, 95% CI = 0.31–0.96). For -cryptoxanthin there was a borderline significant protective association for gastric non-cardia cancer (RR = 0.88 per quartile, 95% CI = 0.76–1.0). In contrast, we found the incidence of gastric non-cardia cancer increased (RR = 1.2 per quartile, 95% CI = 1.0–1.3) with increasing concentration of serum lutein/zeaxanthin. Conclusions: In this population, we found that low retinol and high lutein/zeaxanthin concentrations increased the risks of gastric cardia and gastric non-cardia cancer respectively. We found that there were no strong associations between any of the other analytes and any of the cancer sites. 相似文献