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51.
Aims/IntroductionWe examined the impact of scanning frequency with flash glucose monitoring on glycemic control in children and adolescents with type 1 diabetes.Materials and MethodsThe study included 85 patients, aged 14.0 ± 0.5 years, with type 1 diabetes. The median time in the target glucose range (TIR) and glycosylated hemoglobin (HbA1c) values were 50.0 ± 1.4% and 7.5 ± 0.1%, respectively.ResultsThe median scanning frequency using flash glucose monitoring was 12.0 ± 0.4 times/day. Scanning frequency showed a significant positive correlation with TIR and an inverse correlation with HbA1c. Scanning frequency was identified to be the determinant of TIR and HbA1c by using multivariate analysis. The participants whose scanning frequency was <12 times/day were categorized as the low‐frequency group (n = 40), and those who carried out the scanning >12 times/day were categorized as the high‐frequency group (n = 45). Patients in the high‐frequency group were more likely to be treated with insulin pumps compared with those in the low‐frequency group; however, this difference was not significant (21.3 vs 5.3%, P = 0.073). The high‐frequency group showed significantly greater TIR than the low‐frequency group (57 ± 1.6 vs 42 ± 1.7%, P = 0.002). Furthermore, the high‐frequency group showed significantly lower HbA1c levels than the low‐frequency group (6.8 ± 0.1 vs 8.0 ± 0.1%, P < 0.001).ConclusionsThese findings showed that patients with a higher scanning frequency had better glycemic control, with greater TIRs and lower HbA1c levels, compared with those with a lower scanning frequency. Scanning frequency of >12 times/day might contribute to better glycemic outcomes in real‐world practice in children with type 1 diabetes.  相似文献   
52.
BACKGROUND AND PURPOSE: Symptomatic progression is frequently observed in lacunar infarcts. The exact mechanisms of this phenomenon have not yet been clarified. SUMMARY OF CASES: We report 2 patients with lenticulostriate artery infarcts that presented with skip lesions that were restricted to gray matter. One of the patients subsequently developed symptomatic deterioration; the other experienced no further neurological events. CONCLUSIONS: A possible mechanism of differential vulnerability to ischemia of gray and white matter is considered. White matter may have a longer therapeutic time window for neuroprotective treatment than gray matter.  相似文献   
53.
The hippocampal dentate gyrus in adult animals is known to contain neural progenitors that proliferate and differentiate into neurons in response to brain injury. Little has been observed, however, on regeneration of the granule cell layer of the dentate gyrus that has been directly injured. Using trimethyltin (TMT)-treated mice as an in vivo model, we evaluated the ability of this layer to regenerate after injury. The administration of TMT induced neuronal death in the dentate gyrus selectively 2 days later, with recovery of granule neurons on day 14 and thereafter. At an early stage (days 2-5) after the damage by TMT treatment, 5-bromo-2'-deoxyuridine (BrdU) incorporation into at least two different types of cells was facilitated in the dentate gyrus: BrdU-positive/neuronal nuclear antigen (NeuN)-negative cells were found predominantly in the subgranular zone and granule cell layer, whereas BrdU-positive/NeuN-positive cells were numerous in the dentate molecular layer and hilus. In addition, expression of proliferating cell nuclear antigen, nestin, NeuroD3, and doublecortin, which are markers for proliferating cells and neural progenitors/neuronal precursors, was extremely enhanced in the dentate gyrus at the early stage after treatment. Double staining revealed that BrdU was colocalized with nestin and doublecortin in the subgranular zone. Behavioral analysis revealed that TMT-induced cognition impairment was ameliorated by day 14 after the treatment. Taken together, our data indicate that the hippocampal dentate gyrus itself is capable of regenerating the neuronal cell layer through rapid enhancement of neurogenesis after injury.  相似文献   
54.
We present two cases of patients with schizophrenia treated with minocycline. Minocycline (a second-generation tetracycline) is an established and safe broad-spectrum antibiotic that crosses the blood-brain barrier, with additional efficacy for diseases such as acne and rheumatoid arthritis. Animal studies have suggested that minocycline may prevent progression of some neurological disorders. Moreover, it has been reported that minocycline might have antidepressant effects. We report two cases of acute schizophrenia with predominant catatonic symptoms that responded to minocycline.  相似文献   
55.
Knee osteoarthritis (OA) is becoming more prevalent worldwide due to increases in the numbers of elderly and obese patients. Currently, pharmaceutical medicines used for the treatment of OA are for symptomatic therapy and therefore new therapeutic agents are needed. Kaempferia parviflora (KP) is a plant growing naturally in Southeast Asia and has various pharmacological effects including an anti-inflammatory effect, but no effect on OA has yet been reported. We therefore conducted a search for the effects KP and the active components of KP extract (KPE) exert on OA as well as its mechanism of action. Results from a study of KPE using the monoiodoacetic acid rat OA model revealed that KPE reduced the pain threshold and severity of osteoarthritic cartilage lesions. The mechanism of action and active components were then investigated using IL-1β-treated human knee-derived chondrocytes. KPE, as well as 5,7-dimethoxyflavone and 5,7,4′-trimethoxyflavone, which are key constituents of KPE and highly absorbable into the body, reduced the expression of matrix metalloproteinases (MMPs), which are the main extracellular matrix enzymes that degrade collagen within cartilage. As mentioned above, KPE acted to suppress OA and 5,7-dimethoxyflavone and 5,7,4′-trimethoxyflavone were shown to be involved as part of KPE’s mechanism that inhibits MMPs.  相似文献   
56.

Background

Septal penetration causes underestimation of the heart-to-mediastinum (H/M) ratio in cardiac 123I-metaiodobenzylguanidine (MIBG) imaging with a low-energy high-resolution (LEHR) collimator. We aimed to improve the method of estimating the H/M ratios using the LEHR collimator.

Methods and Results

4 hours after 123I-MIBG injection, 40 patients were imaged successively with the medium-energy (ME) and LEHR collimators using gamma cameras having 3/8-inch crystals. Severe underestimation of the H/M ratios was observed with the LEHR collimator when compared to the ME collimator. Narrowing the energy window width did not reduce the underestimation. Application of 123I-dual-window (IDW) correction using a narrow or wide subwindow reduced the underestimation substantially but not entirely. The H/M ratios estimated from the LEHR images with or without IDW correction were corrected based on their correlations with the ratios estimated from the ME images. This empiric correction removed systematic underestimation, and residual errors were reduced when the H/M ratios after IDW correction were converted using the empiric equation. The conversion equation was successfully applied to the correction of the H/M ratios determined in another 40 patients using a 5/8-inch crystal.

Conclusions

In estimating the H/M ratios using an LEHR collimator, empiric correction combined with IDW correction improves concordance with ME-based values in comparison with empiric correction alone.  相似文献   
57.
A method for the measurement of temperature in the lateral ventricle using diffusion‐weighted imaging (DWI) has been proposed recently. This method uses predetermined arbitrary thresholds, but a more objective method of calculation would be useful. We therefore compared four different calculation methods, two of which were newly created and did not require predetermined thresholds. A rectangular polyethylene terephthalate bottle (8 × 10 × 28 cm3) was filled with heated water (35.0–38.8 °C) and used as a water phantom. The DWI data of 23 healthy subjects (aged 26–75 years; mean ± standard deviation, 50.13 ± 19.1 years) were used for this study. The temperature was calculated using the following equation: T(°C) = 2256.74/ln(4.39221/D) ? 273.15, where D is the diffusion coefficient. The mean ventricular temperature was calculated by four methods: two thresholding methods and two histogram curve‐fitting methods. As a reference, we used the temperature measured at the tympanic membrane, which is known to be approximately 1 °C lower than the brain temperature. The averaged differences in temperature between mercury thermometry and classical predetermined thresholding methods for the water phantom were 0.10 ± 0.42 and 0.05 ± 0.41 °C, respectively. The histogram curve‐fitting methods, however, yielded temperatures a little lower (averaged differences of ?0.24 ± 0.32 and ?0.14 ± 0.31 °C, respectively) than mercury thermometry. There was very little difference in temperature between tympanic thermometry and classical predetermined thresholding methods (+0.01 and ?0.07 °C, respectively). In humans, however, the histogram curve‐fitting methods yielded temperatures approximately 1 °C higher (+1.04 °C and +1.36 °C, respectively), suggesting that temperatures measured in this way more closely approximate the true brain temperature. The histogram curve‐fitting methods were more objective and better matched the estimated brain temperature than did classical predetermined thresholding methods, although the standard deviation was wider in the former methods. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
58.
DJ‐1 has been identified as a gene responsible for recessive familial Parkinson's disease (familial Parkinsonism), which is caused by a mutation in the PARK7 locus. Consistent with the inferred correlation between Parkinson's disease and mitochondrial impairment, mitochondrial localization of DJ‐1 and its implied role in mitochondrial quality control have been reported. However, the mechanism by which DJ‐1 affects mitochondrial function remains poorly defined, and the mitochondrial localization of DJ‐1 is still controversial. Here, we show the mitochondrial matrix localization of various pathogenic and artificial DJ‐1 mutants by multiple independent experimental approaches including cellular fractionation, proteinase K protection assays, and specific immunocytochemistry. Localization of various DJ‐1 mutants to the matrix is dependent on the membrane potential and translocase activity in both the outer and the inner membranes. Nevertheless, DJ‐1 possesses neither an amino‐terminal alpha‐helix nor a predictable matrix‐targeting signal, and a post‐translocation processing‐derived molecular weight change is not observed. In fact, wild‐type DJ‐1 does not show any evidence of mitochondrial localization at all. Such a mode of matrix localization of DJ‐1 is difficult to explain by conventional mechanisms and implies a unique matrix import mechanism for DJ‐1 mutants.  相似文献   
59.
Immunoglobulin G4-related disease (IgG4-RD) is a systemic inflammatory disease characterized by infiltration of extensive IgG4-positive plasma cells and lymphocytes. Although IgG4-RD has been observed in almost all organs, it rarely affects the myocardium. Cardiovascular lesions of IgG4-RD appear as aortic (aortic aneurysm and aortitis) and pericardial (constrictive pericarditis) lesions as well as pseudotumors around the coronary arteries. We herein report a case of IgG4-RD with a cardiac mass in the right atrium involving a sinus node. This condition caused arrhythmia and repeated strokes. We successfully treated the patient through resection of the cardiac mass, catheter ablation and immunosuppressive therapy.  相似文献   
60.
The influence of age and diet on the ultrastructure of hepatocytes is reported. The following dietary manipulations were investigated: Group 1, fed ad libitum a diet containing 21% protein; Group 2, fed a similar diet but restricted to 60% of the intake of Group 1 from 6 weeks of age onwards; Group 3, restricted from 6 weeks to 6 months of age and thereafter fed ad libitum; Group 4, restriction started at 6 months of age; Group 5, fed ad libitum a diet containing 12.6% protein. In all groups the size of hepatocytes was found not to increase during adult life. The size of hepatocytes in Groups 2 and 4 was the same as or larger than that of the other groups; thus food restriction resulted in a decreased number of hepatocytes. Changes in the structure of some organelles and the accumulation of lipofuscin granules occurred with advancing age and the extent of these age-related changes was less in Groups 2 and 4 than in the other groups. These morphologic findings in conjunction with our previously reported metabolic findings provide a new view of the action of food restriction on the aging process. ACTA PATHOL JPN 38: 1119∼1130, 1988.  相似文献   
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