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981.
The role of estrogen in cardiovascular disease 总被引:11,自引:0,他引:11
Baker L Meldrum KK Wang M Sankula R Vanam R Raiesdana A Tsai B Hile K Brown JW Meldrum DR 《The Journal of surgical research》2003,115(2):325-344
Cardiovascular disease is the number one cause of death among women, accounting for nearly 50% of female deaths. Statistics show that women on average develop cardiovascular disease 10 to 15 years later in life than men, and that the risk may increase after menopause. This observation has led to much speculation as to what physiological change(s) associated with menopause is responsible for the higher risk of atherosclerosis. Estrogen, with its potential as a cardioprotective agent and as an immunomodulator of the inflammatory response in atherosclerosis, has received the most attention. Understanding the mechanisms that lead to these differences may allow beneficial therapeutic intervention to enhance this effect in females and evoke this protection in males. This review will do the following: (1) characterize mechanisms of atherosclerosis, (2) explore the role of estrogen-replacement therapy, (3) define the effect of gender on inflammation, (4) compare and contrast the effects of estrogen and testosterone on endothelial functional, and (5) suggest mechanistic based therapeutic opportunities. 相似文献
982.
In vivo autofluorescence spectroscopy of oral premalignant and malignant lesions: distortion of fluorescence intensity by submucous fibrosis 总被引:1,自引:0,他引:1
BACKGROUND AND OBJECTIVES: To test whether autofluorescence spectroscopy can be used for the diagnosis of oral neoplasia in a high-risk population, we characterized the in vivo autofluorescence spectra from oral submucous fibrosis (OSF) lesions and oral premalignant and malignant lesions in both OSF and non-OSF patients. STUDY DESIGN/MATERIALS AND METHODS: Autofluorescence emission spectra were measured under the excitation wavelength of 330 nm, using a Xenon lamp-based fluorospectrometer coupled to a handheld optical fiber probe. Autofluorescence spectroscopies were analyzed among patients with OSF lesions, and oral lesions of epithelial hyperkeratosis (EH), epithelial dysplasia (ED), and squamous cell carcinomas (SCC) and normal oral mucosa (NOM) of healthy volunteers. RESULTS: We found that the most intensely autofluorescence emission peaks occurred at 380 nm and 460 nm. For comparing the spectral patterns among different groups of oral lesions and NOM, ratios of the area under the spectrum of 460+/-10 nm to that under the spectrum of 380+/-10 nm (denoted as A(460+/-10nm)/A(380+/-10nm)) were calculated. The mean ratio values increased gradually from OSF to NOM, to EH and ED, and to SCC. The ANOVA test showed significant differences in the ratio value among all categories of samples (P<0.01). On the other hand, we found that EH, ED, and SCC lesions on OSF patients had distorted autofluorescence intensity. The mean ratio values of EH, ED, and SCC between non-OSF and OSF patients show significant differences. Furthermore, an ANOVA test showed NOM is not distinguishable from EH and ED lesions on oral fibrotic mucosa (P>0.05). CONCLUSIONS: Autofluorescence spectroscopy can be used to diagnose EH, ED, and SCC lesions in non-OSF patients but not in OSF patients. 相似文献
983.
PLS-ANN based classification model for oral submucous fibrosis and oral carcinogenesis 总被引:3,自引:0,他引:3
BACKGROUND AND OBJECTIVES: For effective management of oral neoplasia, autofluorescence spectroscopy was conducted on patients with different characteristics of oral lesions in vivo. This study tested the possibility of using a multivariate statistical algorithm to differentiate human oral premalignant and malignant lesions from benign lesions or normal oral mucosa. STUDY DESIGN/MATERIALS AND METHODS: A fiber optics-based fluorospectrometer was used to measure the autofluorescence spectra from healthy volunteers (NOM) and patients with oral lesions of submucous fibrosis (OSF), epithelial hyperkeratosis (EH), epithelial dysplasia (ED), and squamous cell carcinoma (SCC). A partial least-squares and artificial neural network (PLS-ANN) classification algorithm was used to characterize these oral lesions to discriminate premalignant (ED) and malignant (SCC) tissues from "benign" (NOM, OSF, and EH) tissues. RESULTS: The normalized and centerized spectra of the different kinds of samples showed similar but divergent patterns. Our PLS-ANN classification algorithm could differentiate "premalignant and malignant" tissues from "benign" tissues with a sensitivity of 81%, a specificity of 96%, and a positive predictive value of 88%. CONCLUSIONS: We conclude that the PLS-ANN classification algorithm based on autofluorescence spectroscopy at 330-nm excitation is useful for in vivo diagnosis of OSF as well as oral premalignant and malignant lesions. 相似文献
984.
OBJECTIVES: Osteocalcin is a vitamin-K dependent protein which is related to the metabolism of bone and calcium. The formation or progression of prostate cancer is presumed to be associated with the osteocalcin gene. The most frequently seen polymorphism is HindIII which is located at the promoter region. HindIII is therefore a possible genetic marker in the search for the association between prostate cancer and normal control subjects. METHODS: In our study, a normal control group of 132 healthy people and 96 patients with prostate cancer were examined. The polymorphism was seen following polymerase chain reaction (PCR) based restriction analysis. RESULTS: The result revealed significant differences between normal individuals and cancer patients (p=0.034) and the distribution of the "CC" homozygote in the control group was higher than that in the patient group. No statistical differences were found in clinical staging and grading. The 54 patients who received hormone therapy were further categorized into response and non-response groups, statistical differences between these two groups were revealed (p=0.007, Fisher's exact test). CONCLUSIONS: Based on our results, we conclude that the HindIII polymorphism of the osteocalcin gene is a suitable genetic marker of prostate cancer which can be used in the prediction of the outcome of patients who receive hormone therapy. 相似文献
985.
986.
987.
A 62 year-old man sustained esophageal perforation following intra-operative transesophageal echocardiography (TEE) in a valvular replacement surgery. Septic shock developed on the 12th postoperative day (POD) and the esophageal perforation was diagnosed with chest CT. Emergent operation together with intensive care saved the patient's life. We speculate that the mechanism of perforation was not due to manipulation of the probe, but rather due to ischemia of the esophagus resulting from the combination of probe compression, non-pulsatile flow and the distension of the atria during a lengthy procedure. It is advisable that in patients with operative risk factors, such as distension of atria, long cardiac procedure and likely ischemia of organs due to cardiopulmonary bypass, the monitoring probe of TEE should not constantly rest in the esophagus and be withdrawn when it is idle or not in actual use. In addition, if resistance has been met during the intraoperative manipulation of the probe in a patient without previous history of esophageal disease, perforation might suspected if he or she sustains postoperative fever with positive chest X-ray findings. 相似文献
988.
BACKGROUND: Zolpidem is a new hypnotic that is supposed to have fewer side effects than traditional benzodiazepines. Some psychotic reactions, such as visual or hypnagogic hallucinations, have been reported to be associated with zolpidem use. CASE REPORT: A young female experienced three episodes of hallucination associated with the use of zolpidem. The visual or hypnagogic hallucination happened after she had stopped zolpidem and then restarted it 2 days later. CONCLUSION: We postulate that hypnagogic or visual hallucinations associated with zolpidem use may be related to rapid withdrawal and restarting of zolpidem. The possible mechanism may be associated with the changes in the GABAA receptor. Avoiding "as needed" use of zolpidem and using the lowest effective dose may prevent these adverse effects. 相似文献
989.
Huang YB Fang JY Wu PC Chen TH Tsai MJ Tsai YH 《Biological & pharmaceutical bulletin》2003,26(7):983-987
Blood glucose levels are routinely obtained by invasive and painful methods using glucose meters and test strips. The development of less invasive or non invasive techniques would be beneficial for diabetes patients. In this study, a noninvasive method was evaluated using the back diffusion of glucose across skin with or without permeation enhancement methods. An in vitro model was utilized. The stratum corneum (SC) was the predominant barrier for both back and forward diffusion of glucose across skin. Surfactants with various charges and essential oils (cyclic monoterpenes) were used as chemical enhancers to promote the back diffusion of glucose. A cationic surfactant (benzalkonium chloride) showed the highest enhancement, followed by anionic and nonionic surfactants. d-Limonene and 1,8-cineole dispersed in appropriate proportions of ethanol could enhance the glucose diffusion after pretreatment of the skin surface. Electroporation, defined as a physical method, significantly increased the amount of glucose that diffused back. The percentages of diffused glucose by 300 V (volts) and 500 V high voltage pulses on skin for 10 min were found to be 45 and 75 times greater than the control group, respectively. 相似文献
990.
Tsai SS Yu HS Liu CC Yang CY 《Journal of toxicology and environmental health. Part A》2003,66(11):987-994
The objective of this study was to determine whether women living in the vicinity of industrial districts where emission levels of air contaminants from multiple sources including petrochemical, petroleum, steel, and shipbuilding industries are highly correlated with increased incidence of preterm births. The prevalence of delivery of preterm-birth infants was significantly higher in mothers living in the industrial study area compared to control regions of Taiwan. After controlling for several possible confounders (including maternal age, season, marital status, maternal education, infant gender, and birthplace), the adjusted odds ratio was 1.11 (95% CI = 1.02-1.21) for delivery of preterm infants in the industrial area. Data provide further support for the hypothesis that air pollution can affect the outcome of pregnancy, although a semiecological study cannot confirm a direct causal relationship. 相似文献