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991.
There is increasing recognition that magnetic resonance (MR) imaging and spectroscopy may provide important information in the assessment of patients with acute brain injury. However, optimum care of the acutely head injured patient requires monitoring of intracranial pressure (ICP). Although many monitoring modalities have been integrated into commercially available MR-compatible systems, there have been no reports of commonly used intraparenchymal ICP sensors in an MR environment. The authors describe the use of an ICP micromanometer probe in an MR environment, with a fiberoptic connection that interfaces the probe with a commercially available MR-compatible monitoring system. Phantom studies were performed to demonstrate the safety and compatibility of the modified MR system at 0.5 tesla. The safety of the device was assessed in relation to its interaction with the static, gradient, and radiofrequency fields used in MR imaging. The MR compatibility was documented by demonstrating that its performance was unaffected by the operation of imaging sequences and by showing that there was no degradation of the diagnostic quality of imaging data obtained during ICP monitoring.  相似文献   
992.
993.
Suboptimal dietary intake is a critical cause of poor maternal nutrition, with several adverse consequences both for mothers and for their children. This study aimed to (1) assess maternal dietary patterns in India; (2) examine enablers and barriers in adopting recommended diets; (3) review current policy and program strategies to improve dietary intakes. We used mixed methods, including empirical analysis, compiling data from available national and subnational surveys, and reviewing literature, policy, and program strategies. Diets among pregnant women are characterized by low energy, macronutrient imbalance, and inadequate micronutrient intake. Supply- and demand-side constraints to healthy diets include food unavailability, poor economic situation, low exposure to nutrition counselling, food restrictions and taboos, adverse family influence and gender norms, and gaps in knowledge. Intervention strategies with potential to improve maternal diets include food-based programs, behavior change communication, and nutrition-sensitive agriculture interventions. However, strategies face implementation bottlenecks and limited effectiveness in real-world at-scale impact evaluations. In conclusion, investments in systems approaches spanning health, nutrition, and agriculture sectors, with evaluation frameworks at subnational levels, are needed to promote healthy diets for women.  相似文献   
994.
995.
Hyperoxaluria is a major risk factor for the formation of calcium oxalate stones, but dietary restriction of oxalate intake might not be a reliable approach to prevent recurrence of stones. Hence, other approaches to reduce urinary oxalate to manage stone disease have been explored. The gut‐dwelling obligate anaerobe Oxalobacter formigenes (OF) has attracted attention for its oxalate‐degrading property. In this review we critically evaluate published studies and identify major gaps in knowledge. Recurrent stone‐formers are significantly less likely to be colonized with OF than controls, but this appears to be due to antibiotic use. Studies in animals and human subjects show that colonization of the gut with OF can decrease urinary oxalate levels. However, it remains to be determined whether colonization with OF can affect stone disease. Reliable methods are needed to detect and quantify colonization status and to achieve durable colonization. New information about oxalate transport mechanisms raises hope for pharmacological manipulation to decrease urinary oxalate levels. In addition, probiotic use of lactic acid bacteria that metabolize oxalate might provide a valid alternative to OF.  相似文献   
996.
Liver transplantation(LT) for hepatocellular carcinoma(HCC) has been established as a standard treatment in selected patients for the last two and a half decades. After initially dismal outcomes, the Milan criteria(MC)(single HCC ≤ 5 cm or up to 3 HCCs ≤ 3 cm) have been adopted worldwide to select HCC patients for LT, however cumulative experience has shown that MC can be too strict. This has led to the development of numerous expanded criteria worldwide. Morphometric expansions on MC as well as various criteria which incorporate biomarkers as surrogates of tumor biology have been described. HCC that presents beyond MC initially can be downstaged with locoregional therapy(LRT). Post-LRT monitoring aims to identify candidates with favorable tumor behavior. Similarly, tumor marker levels as response to LRT has been utilized as surrogate of tumor biology. Molecular signatures of HCC have also been correlated to outcomes; these have yet to be incorporated into HCC-LT selection criteria formally. The ongoing discrepancy between organ demand and supply makes patient selection the most challenging element of organ allocation. Further validation of extended HCCLT criteria models and pre-LT treatment strategies are required.  相似文献   
997.
Community health workers (CHWs) increasingly provide interpersonal counselling to childbearing women and their families to improve adoption of recommended maternal and child nutrition behaviours. Little is known about CHWs'' first‐hand experiences garnering family support for improving maternal nutrition and breastfeeding practices in low‐resource settings. Using focused ethnography, we drew insights from the strategies that CHWs used to persuade influential family members to support recommendations on maternal diet, rest and breastfeeding in a behaviour change communication trial in rural Bangladesh. We interviewed 35 CHWs providing at‐home interpersonal counselling to pregnant women and their families in seven ‘Alive & Thrive’ intervention sites. In‐depth probing focused on how CHWs addressed lack of family support. Thematic coding based on Fisher''s narrative paradigm revealed strategic use of three rhetorical principles by CHWs: ethos (credibility), pathos (emotion) and logos (logic). CHWs reported selectively targeting pregnant women, husbands and mothers‐in‐law based on their influence on behavioural adoption. Key motivators to support recommended behaviours were improved foetal growth and child intelligence. Improved maternal health was the least motivating outcome, even among mothers. Logically coherent messaging resonated well with husbands, while empathetic counselling was additionally required for mothers. Mothers‐in‐law were most intransigent, but were persuaded via emotional appeals. Persuasion on maternal rest was most effort‐intensive, resulting in contextually appealing but scientifically inaccurate messaging. Our study demonstrates that CHWs can offer important insights on context‐relevant, feasible strategies to improve family support and uptake of nutrition recommendations. It also identifies the need for focused CHW training and monitoring to address scientifically flawed counselling narratives.  相似文献   
998.
Anaemia control programmes in India are hampered by a lack of representative evidence on anaemia prevalence, burden and associated factors for adolescents. The aim of this study was to: (1) describe the national and subnational prevalence, severity and burden of anaemia among Indian adolescents; (2) examine factors associated with anaemia at national and regional levels. Data (n = 14,673 individuals aged 10–19 years) were from India''s Comprehensive National Nutrition Survey (CNNS, 2016–2018). CNNS used a multistage, stratified, probability proportion to size cluster sampling design. Prevalence was estimated using globally comparable age‐ and sex‐specific cutoffs, using survey weights for biomarker sample collection. Burden analysis used prevalence estimates and projected population from 2011 Census data. Multivariable logistic regression models were used to analyse factors (diet, micronutrient deficiencies, haemoglobinopathies, sociodemographic factors, environment) associated with anaemia. Anaemia was present in 40% of girls and 18% of boys, equivalent to 72 million adolescents in 2018, and varied by region (girls 29%–46%; boys 11%–28%) and state (girls 7%–62%; boys 4%–32%). Iron deficiency (ferritin < 15 μg/L) was the strongest predictor of anaemia (odds ratio [OR]: 4.68, 95% confidence interval [CI]: [3.21,6.83]), followed by haemoglobinopathies (HbA2 > 3.5% or any HbS) (OR: 2.81, 95% CI: [1.66,4.74]), vitamin A deficiency (serum retinol <20 ng/ml) (OR: 1.86, 95% CI: [1.23,2.80]) and zinc deficiency (serum zinc < 70 μg/L) (OR: 1.32, 95% CI: [1.02,1.72]). Regional models show heterogeneity in the strength of association between factors and anaemia by region. Adolescent anaemia control programmes in India should continue to address iron deficiency, strengthen strategies to identify haemoglobinopathies and other micronutrient deficiencies, and further explore geographic variation in associated factors.  相似文献   
999.
(1) Background: Vitamin D supplementation has been proposed for the prevention and treatment of COVID-19, but it is not clear if reduced serum vitamin D predisposes individuals to COVID-19 and/or is a secondary consequence of infection. This study assessed the temporal association between serum vitamin D and COVID-19 with two single-institution case–control studies through the University of California San Diego (UCSD) Health System. (2) Methods: This study included patients who tested positive for COVID-19 from 1 January to 30 September 2020 with serum 25-hydroxy-vitamin D (25(OH)D) measured within 180 days of diagnosis. Patients were separated based on whether 25(OH)D was measured before (n = 107 cases, 214 controls) or after (n = 203 cases, 406 controls) COVID-19 diagnosis. COVID-19 infection status was the outcome variable in the pre-diagnosis study, whereas serum 25(OH)D level was the outcome variable in the post-diagnosis study. (3) Results: Serum 25(OH)D levels were not associated with the odds of subsequent COVID-19 infection (OR 1.0, 95% CI: 1.0 to 1.0, p = 0.98). However, COVID-19-positive individuals had serum 25(OH)D measurements that were 2.7 ng/mL lower than the controls (95% CI: −5.2 to −0.2, p = 0.03). (4) Conclusions: In our study population, serum 25(OH)D levels were not associated with the risk of acquiring COVID-19 infection but were reduced in subjects after COVID-19 infection. These results support the possibility that reduced serum 25(OH)D is a consequence and not a cause of COVID-19 infection.  相似文献   
1000.

Background and purpose:

Reactive oxygen species (ROS) derived from Nox2-containing reduced form of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity is reportedly detrimental in cerebrovascular disease. However, ROS generation by other Nox isoforms may have a physiological role. No Nox2-selective inhibitors have yet been identified, and thus it is unclear whether isoform non-selective Nox inhibitors would necessarily improve outcome after stroke. We assessed the effect of apocynin on cerebrovascular ROS production and also on outcome following cerebral ischaemia when administered either before ischaemia or after cerebral reperfusion. The involvement of Nox2-containing NADPH oxidase in the effects of apocynin was assessed using Nox2−/− mice.

Experimental approach:

Transient cerebral ischaemia was induced by 0.5 h middle cerebral artery occlusion followed by 23.5 h reperfusion. Mice received apocynin (2.5 mg·kg−1, i.p.) either 0.5 h before ischaemia or 1 h after reperfusion. In situ superoxide production after cerebral ischaemia-reperfusion was measured in brain sections of wild-type mice at 24 h using dihydroethidium fluorescence.

Key results:

Treatment with apocynin 0.5 h before ischaemia reduced total infarct volume, neurological impairment and mortality in wild-type but not Nox2−/− mice. Conversely, treatment with apocynin 1 h after initiation of reperfusion had no protective effect. Cerebral ischaemia and reperfusion increased superoxide production in the brain at 24 h, and pretreatment but not posttreatment with apocynin reduced superoxide levels.

Conclusions and implications:

Apocynin improves outcome following stroke when administered before ischaemia in wild-type but not Nox2−/− mice.  相似文献   
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