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101.
Dystrophic calcinosis cutis is diagnosed when calcium is deposited into previously damaged tissue by connective tissue disease, panniculitis, pseudoxanthoma elasticum or trauma. We report a case of dystrophic calcinosis cutis arising from the lesion of an epidermal cyst on the verrucous epidermal nevus. A 20‐year‐old woman presented with a polypoid pinkish tumor on a brownish, verrucous plaque. Histopathological findings of the pinkish tumor showed calcium deposits as amorphous, basophilic material lining the true epidermis in the upper dermis, which were compatible with dystrophic calcinosis cutis and the plaque was diagnosed as a verrucous epidermal nevus.  相似文献   
102.
Carotid angioplasty and stenting (CAS) for carotid stenosis has been increasingly used as an alternative treatment in patients not eligible for surgery. Even though CAS can be performed relatively simply in many cases, various complications can occur. We report four cases of CAS using the Carotid Wallstent, which were complicated by delayed shortening of the stent, resulting in restenosis after successful CAS.  相似文献   
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Serial immunoreactive erythropoietin levels in autologous blood donors   总被引:1,自引:0,他引:1  
The variations in plasma erythropoietin (EPO) concentration during preoperative deposit of autologous blood were studied in 12 patients (8 men, 4 women). Four donations were scheduled at weekly intervals. A predonation hemoglobin concentration of 11 g per dL (110 g/L) was required. Hemoglobin concentration decreased from 14.3 +/- 1.1 g per dL (143 +/- 11 g/L) (mean +/- SD) before the first donation to 11.7 +/- 0.7 g per dL (117 +/- 7 g/L) on Day 22 (p less than or equal to 0.0001). Reticulocyte counts increased from a median of 31,800 (range, 4900-95,000) per microL (median, 32 x 10(9)/L [range, 5-95 x 10(9)/L]) to 93,800 (16,800-194,900) per microL (median, 94 x 10(9)/L [range, 17-195 x 10(9)/L]) on Day 28 (p less than or equal to 0.01). Plasma EPO concentration was 17.8 +/- 5.1 mU per mL prior to the first donation and displayed a small and transient peak after each donation. A sustained elevation followed each peak. Although plasma EPO concentration differed significantly from the baseline value after the first donation, only the peak concentrations after the second (35.5 +/- 15.5 mU/mL), third (38.0 +/- 14.5 mU/mL), and fourth (36.1 +/- 11.0 mU/mL) donations exceeded the normal range. The moderate, biphasic increase in plasma EPO concentration and the moderate increase in erythropoiesis suggest two strategies in autologous blood donation that should be investigated with respect to efficiency and safety: 1) more aggressive donation schemes, which reduce donation intervals and/or the minimum hemoglobin concentration and 2) the administration of recombinant human EPO.  相似文献   
106.
Pathological hallmarks of Alzheimer's disease (AD) include extracellularly accumulated amyloid β (Aβ) plaques and intracellular neurofibrillary tangles in the brain. Activated microglia, brain‐resident macrophages, are also found surrounding Aβ plaques. The study of the brain of AD mouse models revealed that Aβ plaque formation is completed by the consolidation of newly generated plaque clusters in vicinity of existed plaques. However, the dynamics of Aβ plaque formation, growth and the mechanisms by which microglia contribute to Aβ plaque formation are unknown. In the present study, we confirmed how microglia are involved in Aβ plaque formation and their growth in the brain of 5XFAD mice, the Aβ‐overexpressing AD transgenic mouse model, and performed serial intravital two‐photon microscopy (TPM) imaging of the brains of 5XFAD mice crossed with macrophage/microglia‐specific GFP‐expressing CX3CR1GFP/GFP mice. We found that activated microglia surrounding Aβ plaques take up Aβ, which are clusters developed inside activated microglia in vivo and this was followed by microglial cell death. These dying microglia release the accumulated Aβ into the extracellular space, which contributes to Aβ plaque growth. This process was confirmed by live TPM in vivo imaging and flow cytometry. These results suggest that activated microglia can contribute to formation and growth of Aβ plaques by causing microglial cell death in the brain. GLIA 2016;64:2274–2290  相似文献   
107.
Seasonal and pandemic influenza infections remain a serious public health concern. Many health authorities recommend annual vaccination as the most effective way to control influenza infection. Accordingly, regulatory guidelines ask vaccine manufacturers to determine vaccine potency at the time of release and throughout shelf-life to ensure vaccine quality. The potency of inactivated influenza vaccine is related to the quantity of hemagglutinin (HA). Since 1970s, single radial immunodiffusion (SRID) assay has been standardly used for the quantitation of HA in influenza vaccine. However, SRID is labor-intensive, inaccurate, and requires standard reference reagents that should be updated annually. Therefore, there have been extensive efforts to develop alternative potency assays. In this study, we developed and tested a new HA quantitative enzyme-linked immunosorbent assay (ELISA) using a universal monoclonal antibody that can bind to HAs from various subtypes in group 1 influenza A virus (IAV). We analyzed the conserved stalk domain of HA via a library approach to design a consensus HA antigen for group 1 IAV. The antigens were expressed as a soluble form in E. coli and were purified by Ni-affinity chromatography. When tested with variety of HAs from IAVs or influenza B viruses (IBVs), the mAbs exhibited specific binding to group 1 HAs, with potential exception to H9 subtype. Among various conditions of pH, urea, and reducing agents, pretreatment of HA at low pH exposing the conserved stalk domain was crucially important for optimal ELISA performance. Calibration curves for various HAs were generated to determine accuracy, specificity, sensitivity, and linear dynamic range. The ELISA method shows high sensitivity and accuracy compared with the SRID assay. The HA group specific universal mAbs against the consensus stalk domain of HA are conducive to establishing an ELISA-based standard procedure for the quantitation of HA antigens for annual vaccination against influenza infection.  相似文献   
108.
Doppler ultrasonography (US) has an advantage of being non‐invasive; therefore, several attempts have been made to investigate the haemodynamic alterations in cirrhosis and the response to medical treatment of portal hypertension. Doppler indices, which have been commonly used for the evaluation of portal hypertension, include the measurement of portal and splenic venous blood velocity and flows, and the resistive and pulsatility index at hepatic, splenic, renal, superior mesenteric artery. Although many positive evidences have been suggested, its clinical usefulness in portal hypertension remains unsettled because of being plagued by lack of reproducibility and accuracy characterized by intra‐ and interobserver variation. However, recently, Doppler's usefulness in assessment of severity of portal hypertension in terms of reproducibility, technical ease and accuracy and response to drugs that reduce the portal pressure has been proposed. In addition, because most of the patients with cirrhosis and portal hypertension have intrahepatic shunts, they show a decrease in intrahepatic circulatory time (IHCT). Doppler US using microbubble contrast agents allows measurement of IHCT. Therefore, application of contrast‐enhanced Doppler US can be prospective for the assessment of the severity of portal hypertension. Several reports have demonstrated that colour Doppler endoscopic US enable haemodynamic study to assess the portal hypertension and has a role of guidance to measure the imaging‐based variceal pressure. We have reviewed briefly the clinical usefulness of Doppler US in assessing the severity of portal hypertension and its response to treatment.  相似文献   
109.

Background

Portal hypertensive gastropathy (PHG) is a common endoscopic finding in patients with cirrhosis. However, the relationship between PHG and portal hypertension is controversial. Furthermore, nothing is known regarding the correlation between PHG and prognosis in patients with cirrhosis.

Methods

The hepatic venous pressure gradient (HVPG), endoscopic PHG grade, Child–Pugh score, and model for end-stage liver disease (MELD) score were assessed at baseline and were followed prospectively in 331 cirrhotic patients (284 males, 85.8%; mean age, 52.16 ± 9.05 years) from January 2001 to April 2009. The relationship between PHG with HVPG and survival was investigated.

Results

The HVPG was significantly higher in patients with severe PHG than in those with mild or no PHG (absent, 4.9 ± 1.7 mmHg; mild, 10.7 ± 4.1 mmHg; severe, 15.6 ± 4.6 mmHg; P < 0.001). During follow-up, 28 patients (8.5%) died from liver-related disease. In the Cox regression analysis, severe PHG (none and mild vs. severe) (hazard ratio 1.153, 95% confidence interval: 1.048–1.269) showed a significantly high relative risk of mortality, and in the Kaplan–Meier analysis, severe PHG showed a significantly shorter expected survival time than none or mild PHG (median survival time, 77.6 ± 9.6 months in severe PHG; log-rank test, P = 0.030).

Conclusions

PHG was associated with portal hypertension severity and prognosis in patients with cirrhosis.  相似文献   
110.
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