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排序方式: 共有186条查询结果,搜索用时 15 毫秒
1.
B Sedgmen C McMahon D Cairns R J Benzie R L Woodfield 《Ultrasound in obstetrics & gynecology》2006,27(3):245-251
OBJECTIVE: To explore the impact of timing and type of ultrasound, particularly three-dimensional (3D), exposure on maternal-fetal attachment and maternal health behavior during pregnancy. METHODS: Subjects were 68 women aged 18 years or older expecting their first child who presented for a routine ultrasound scan at around either 12 or 18 weeks' gestation in Nepean Hospital, Western Sydney. Women completed questionnaires assessing maternal-fetal attachment and health behavior, and were then allocated arbitrarily to either two-dimensional (2D) or 3D ultrasound examination. Repeat questionnaires were completed 1 week later. RESULTS: Maternal-fetal attachment increased after both 2D and 3D ultrasound exposure, and the effect was moderated by the timing of exposure, with women receiving their first ultrasound examination at around 12 weeks showing the greatest change. Alcohol consumption was the only behavior to show significant change following ultrasound exposure, with a reduction in the reported average number of drinks per week. There was no significant difference in the pattern of change for 2D compared with 3D ultrasound exposure, and no effect of ultrasound exposure on maternal perception of the fetus. CONCLUSIONS: Ultrasound has a positive impact on maternal-fetal attachment, particularly in the first trimester. 3D ultrasound did not offer enhanced benefits. Associations between ultrasound exposure and alcohol consumption warrant further investigation. Larger samples are needed to clarify the moderating effects of gestational age and type of ultrasound exposure. 相似文献
2.
Camus Kar Man Choy Pauline Cho Wai-Yuen Chung Iris F F Benzie 《Optometry and vision science》2003,80(9):632-636
BACKGROUND: Tear ascorbate is important for corneal health. A rapid and simple method for measurement of ascorbate in tears is needed, and adequate knowledge of physiological variation of tear ascorbate is important to facilitate comparative studies of the effect of, for example, contact lens wear and environmental conditions and stresses. However, there are currently no data on physiological variation of tear ascorbate. This study validated a simple and speedy method for tear ascorbate and investigated between-eye and between-day variation in tear ascorbate in healthy young adults. METHODS: Yawn-induced reflex tears were collected from 32 healthy Hong Kong Chinese subjects and measured by both high-performance liquid chromatography (HPLC) and by an enzyme-linked colorimetric method known as FRASC (total ferric reducing (antioxidant) activity and ascorbate concentration measurement). For between-eye variation, yawn reflex tears were collected from each eye of the same 32 healthy subjects, and ascorbate was measured using HPLC; in a separate experiment for between-day variation, tears were collected on two separate days from 14 subjects, and ascorbate was measured by FRASC. RESULTS: Both HPLC and FRASC showed high precision, and results obtained using FRASC were not statistically different from those using HPLC; mean +/- SD were, respectively, 18.5 +/- 4.4 microM and 18.5 +/- 4.8 microM for HPLC and FRASC methods (p = 0.943). No significant between-eye difference in tear ascorbate was found (p = 0.386), and no significant between-day variation was found overall: mean +/- SD ascorbate was 20.0 +/- 6.2 microM on day 1 and 19.3 +/- 6.8 microM on day 2 (p = 0.772). However, between-day variation was large in seven of 14 subjects. CONCLUSION: FRASC is an acceptable alternative to HPLC for measurement of tear ascorbate. Tears for ascorbate investigation can be collected from either eye or, if necessary, from both eyes and pooled. However, tear ascorbate may vary widely from day to day in the same individual. The reasons for this variation require further study but may relate to differences in ascorbate supply or demand within the precorneal tear layer. 相似文献
3.
Tam LS Li EK Leung VY Griffith JF Benzie IF Lim PL Whitney B Lee VW Lee KK Thomas GN Tomlinson B 《The Journal of rheumatology》2005,32(2):275-282
OBJECTIVE: Patients with systemic lupus erythematosus (SLE) experience excess morbidity and mortality due to coronary artery disease (CAD) that cannot be fully explained by the classical CAD risk factors. Among emerging CAD risk factors, oxidative stress is currently being emphasized. We evaluated the effects of longterm antioxidant vitamins on markers of oxidative stress and antioxidant defense and endothelial function in 39 patients with SLE. METHODS: Patients were randomized to receive either placebo or vitamins (500 mg vitamin C and 800 IU vitamin E daily) for 12 weeks. Markers of oxidative stress included malondialdehyde (MDA) and allantoin. Antioxidants measured included erythrocyte superoxide dismutase and glutathione peroxidase, plasma total antioxidant power (as FRAP value), and ascorbic acid and vitamin E concentrations. Endothelial function was assessed by flow-mediated dilatation (FMD) of the brachial artery and plasma concentration of von Willebrand factor (vWF) and plasminogen activator inhibitor type 1 (PAI-1). Primary outcome of the study included the change in lipid peroxidation as revealed by MDA levels. Secondary outcomes included changes in allantoin and antioxidant levels and change in endothelial function. RESULTS: After treatment, plasma ascorbic acid and alpha-tocopherol concentrations were significantly (p < 0.05) increased only in the vitamin-treated group, associated with a significant decrease (p < 0.05) in plasma MDA. Other oxidative stress markers and antioxidant levels remained unchanged in both groups. FMD and vWF and PAI-1 levels remained unchanged in both groups. CONCLUSION: Combined administration of vitamins C and E was associated with decreased lipid peroxidation, but did not affect endothelial function in patients with SLE after 3 months of therapy. 相似文献
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Age-related macular degeneration (AMD) is a common disorder that causes irreversible loss of central vision. Increased intake of foods containing zeaxanthin may be effective in preventing AMD because the macula accumulates zeaxanthin and lutein, oxygenated carotenoids with antioxidant and blue light-absorbing properties. Lycium barbarum L. is a small red berry known as Fructus lycii and wolfberry in the West, and Kei Tze and Gou Qi Zi in Asia. Wolfberry is rich in zeaxanthin dipalmitate, and is valued in Chinese culture for being good for vision. The aim of this study, which was a single-blinded, placebo-controlled, human intervention trial of parallel design, was to provide data on how fasting plasma zeaxanthin concentration changes as a result of dietary supplementation with whole wolfberries. Fasting blood was collected from healthy, consenting subjects; fourteen subjects took 15 g/d wolfberry (estimated to contain almost 3 mg zeaxanthin) for 28 d. Repeat fasting blood was collected on day 29. Age- and sex-matched controls (n 13) took no wolfberry. Responses in the two groups were compared using the Mann-Whitney test. After supplementation, plasma zeaxanthin increased 2.5-fold: mean values on day 1 and 29 were 0.038 (sem 0.003) and 0.096 (sem 0.009) micromol/l (P<0.01), respectively, for the supplementation group; and 0.038 (sem 0.003) and 0.043 (sem 0.003) micromol/l (P>0.05), respectively, for the control group. This human supplementation trial shows that zeaxanthin in whole wolfberries is bioavailable and that intake of a modest daily amount markedly increases fasting plasma zeaxanthin levels. These new data will support further study of dietary strategies to maintain macular pigment density. 相似文献
8.
Summary
Background
Antioxidant
defence has been reported to
decrease, and oxidative stress to increase,
after oral glucose loading in
both normal and diabetic subjects.
If confirmed in normal subjects,
glucose–induced antioxidant depletion
has important implications for
health in relation to the modern,
sugar–rich diet.
Aim of the study
To investigate changes in plasma
biomarkers of oxidant:antioxidant
balance in non–diabetic subjects
following oral glucose loading.
Baseline inter–relationships between
biomarkers of glycaemic
control, oxidant:antioxidant balance
and inflammation were also
explored.
Methods
A singleblinded,
placebo–controlled, crossover
intervention trial involving 10
healthy, consenting subjects. Venous
blood was collected after ingestion of 75 g glucose in 300 mL
water, or of water alone. Blood was
collected at 0 time (fasting) and 30,
60, 90, 120 min post–ingestion.
Within 2 weeks the procedure was
repeated with volunteers crossedover
onto the other treatment.
Plasma total antioxidant capacity
(as the FRAP value), ascorbic acid,
–tocopherol, uric acid, malondialdehyde
(MDA), allantoin and
high sensitivity C–reactive protein
(hsCRP), glucose and insulin, were
measured in all samples. Paired results
post–glucose and post–water
at each time interval were compared
using the Wilcoxon
matched–pairs signed–ranks test.
Results
Normal glucose tolerance
was observed in all subjects, although,
as expected, plasma glucose
and insulin increased significantly
(p < 0.05, n = 10) after
glucose loading. Post–glucose responses
in plasma FRAP and the
individual antioxidants tested were
not significantly different to the responses
seen post–water, although
both FRAP and –tocopherol decreased
slightly. Neither were postglucose
changes in plasma MDA
and allantoin, putative biomarkers
of oxidative stress, significantly different
to those after intake of water
alone. Plasma FRAP and -tocopherol
also decreased slightly, but
not significantly, after intake of water.
A significant direct correlation
(r = 0.867, p < 0.001, n = 10) was
found between fasting allantoin
and (log transformed) hsCRP concentrations.
Conclusions
These new
data from a controlled intervention
trial indicate that acute, transient
increases in plasma glucose following
oral intake of a large glucose
load do not, as previously reported,
cause a significant decrease in
plasma antioxidants or increase oxidative
stress in non–diabetic subjects.
This is reassuring given the
large quantities of sugar ingested
by children and adolescents. However,
a small decrease in plasma antioxidant
capacity was seen after
ingestion of water and of glucose,
and it is possible that intake of glucose
without concomitant intake of
antioxidants in susceptible individuals
may cause oxidative stress.
Further work is needed in relation
to diabetic subjects and a possible
glucose threshold for this. The
finding of a direct relationship between
allantoin, a biomarker of oxidative
stress, and hsCRP, a marker
of inflammation and CHD predictor,
in healthy subjects is interesting
and indicates a link between
sub–clinical inflammation and oxidative
stress. 相似文献
9.
A new technique is described for reversing the direction of the catheter tip during translumbar aortography, without the need for partial withdrawal of the catheter from the aortic lumen. The method ensures optimal delivery of contrast medium at the desired level, while avoiding the risk of retroperitoneal bleeding or dislodgement during catheter manipulation. 相似文献
10.
For most age-related disorders there is no cure, and treatment is expensive and often ineffective. Thus, disease prevention is an issue of increasing concern and importance. Nurses form the largest professional healthcare group in the world, and the professional code of the modern day nurse advocates health promotion as a primary role. Nurses, by virtue of their close, direct interaction with their community and clients, are in a strong position to disseminate and reinforce the message of health promotion with the aim of achieving functional longevity in our aging population. This requires that nurses themselves increase their awareness, knowledge and understanding of relevant interdisciplinary research findings. In the current review, the influence of diet on the risk of four of the most prevalent age-related diseases (cancer, cardiovascular disease, dementia and diabetes) is presented, and the underlying mechanisms of influence are discussed, with particular focus on antioxidant-rich foods. 相似文献