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991.
Chronic hepatitis C virus (HCV) infection is associated with a spectrum of liver diseases and a proportion of chronic cases progress through cirrhosis to hepatocellular carcinoma (HCC). The viral and host factors that are important in the clinical and histological progression of HCV infection are unclear. We investigated the effect of moderate (<80 g/day) and heavy (>80 g/day) alcohol intake on the histological and clinical progression of HCV infection and their associated risk of hepatic cancer in a group of Japanese patients. A number of other variables were assessed to evaluate their impact on disease progression. We recruited 120 patients with HCV infection and categorized them into four groups, based on alcohol consumption pattern. All clinical and biochemical profiles were collected from recorded files. Liver biopsies were analysed for the degree of fibrosis, presence of cirrhosis and histological activity of necroinflammation. Hepatic tumours were detected by the follow-up imaging analysis. There was no difference in the age, length of exposure to HCV infection and HCV RNA serum levels in the alcohol and alcohol-free groups. The histological grading of necroinflammation, serum levels of alanine aminotransferase and HCV RNA did not have any correlation with each other in the alcohol and alcohol-free group. There was a 1.5-2. 5-fold greater risk of liver cirrhosis and hepatocellular carcinoma in the alcohol intake group compared to the alcohol-free group. Kruskal-Wallis analysis among four groups demonstrated a significant transition to fibrosis (P < 0.05) for alcoholics with HCV infection. The increased risk of liver cancer in the alcohol group is independent of size and growth of tumours. The clinical manifestations of gastro-oesophageal variceal bleeding, ascites, and encephalopathy were also higher in the alcohol intake group. Alcohol consumption is an important risk factor in the histological and clinical progression of HCV infection and has no relation with HCV replication. Chronic HCV carriers should avoid excessive alcohol intake to reduce the acceleration of liver disease and risk of liver cancer.  相似文献   
992.
Methanol extracts from the bark and wood of ten plants used as chewing sticks in Morogoro region, in Tanzania, were tested for their ability to inhibit the growth of cariogenic bacteria, Streptococcus mutans , Actinomyces viscosus and a yeast Candida albicans . Screening for antimicrobial activity was done by the agar-hole diffusion method, and minimum inhibitory concentrations (MICs) were determined by the agar dilution method. Extracts from seven out of the ten plants showed varying degrees of growth inhibitory effect on the microorganisms, with Acacia senegal var. senegal stem bark being the most active, followed by the stem bark of Eriosema psoraleoides . Their MICs ranged from 0.63 mg/ml to 5 mg/ml. Three plants Ocimum suave , Opilia celtidifolia and Xerophyta suaveolens did not exhibit any antimicrobial effect. Actinomyces viscosus was relatively more sensitive to the extracts than S. mutans and C. albicans . This study has also demonstrated that most bark extracts possessed antimicrobial activity, while many wood extracts were inactive. It is, therefore, advisable to use, for toothbrushing, unpeeled, rather than peeled chewing sticks, in order to exploit fully their antimicrobial effect. However, additional studies are needed to determine their antiplaque, anticaries and antimycotic effects.  相似文献   
993.
Subchronic neurotoxic effects of sarin (O-isopropyl methylphosphonofluoridate) treatment at various doses in male Sprague Dawley rats were studied. The animals were treated with a single intramuscular (im) injection of 0.01, 0.1, 0.5, or 1 x LD50 (100 microg/kg). The animals were maintained for 90 d thereafter. [3H]Hexamethonium iodide was used to monitor the changes in blood-brain barrier (BBB) permeability in cortex, brainstem, midbrain, and cerebellum. Brainstem exhibited a significant decrease (approximately 58% of control) in uptake of [3H]hexamethonium iodide at 1 x LD50 dose. No significant changes were observed in BBB permeability in cortex, midbrain, and cerebellum at any dose. Plasma butyrylcholinesterase (BChE) activity remained unchanged, reflecting recovery of the enzyme activity from the initial inhibition following single exposure of 1 x LD50 sarin. Acetylcholinesterase (AChE) activity in the cortex remained inhibited (approximately 29%), whereas in the brainstem there was an increase (approximately 20%) at 1 x LD50 dose of sarin. The m2-selective muscarinic acetylcholine receptor (m2-mAChR) ligand binding was inhibited significantly at 1 x LD50 in the cortex, whereas brainstem showed significantly increased (approximately 45%) ligand binding at 1 x LD50 dose. Nicotinic acetylcholine receptor (nAChR), on the other hand, showed a biphasic response in ligand binding in the cortex with a decrease (approximately 30%) at 0.01 x LD50 but an increase (approximately 40%) at 1 x LD5O. Brainstem did not show any significant change in nAChR ligand binding. These results suggest that single exposure of sarin could lead to changes that may play an important role in neuropathological abnormalities in the central nervous system.  相似文献   
994.
Three novel monotetrahydrofuran annonaceous acetogenins from Annona montana   总被引:1,自引:0,他引:1  
Three new monotetrahydrofuran (mono-THF) acetogenins, anmontanins A-C (1-3) were isolated from the leaves of Annona montana. Anmontanin C (3) is the first stereochemically pure acetogenin reported to have a gamma-hydroxymethyl-gamma-lactone moiety. Two known mono-THF acetogenins, murisolin and annonacin, were isolated from the seeds of the plant. The structures of compounds 1-3 were elucidated by spectral methods and chemical derivatization.  相似文献   
995.
A new guaianolide, taraxacin (1), and a known sesquiterpene ketolactone (2) have been isolated from an ethyl acetate-soluble part of a methanolic extract of Taraxacum wallichii. The structure of 1 was established using NMR, MS, and X-ray crystallographic methods. The (13)C NMR data of 2 is also being reported for the first time.  相似文献   
996.
CT-2584 HMS, 1-(11-dodecylamino-10-hydroxyundecyl)-3, 7-dimethylxanthine-hydrogen methanesulphonate, is a modulator of intracellular phosphatidic acid. We treated 30 patients as part of a Phase I and pharmacokinetic study to determine the maximum-tolerated dose of CT-2584 HMS, toxicity profiles, pharmacokinetic profile and antitumour effects at escalating dose levels. CT-2584 HMS was given as a continuous infusion for 6 hours for 5 consecutive days every 3 weeks. Plasma samples for pharmacokinetic studies were analysed using a validated high-performance liquid chromatographic assay. Mean C(max)and AUC values for each dose group were similar on days 1 and 5 and increases in plasma concentration (C(max)and AUC) appeared proportional to the dose. CT-2584 HMS had a mean elimination half-life of 7.3 hours. Values of V(d)and clearance were independent of dose and duration of treatment. Dose escalation was halted at 585 mg/m(2)because of malaise and lethargy, which was sometimes accompanied by nausea and headache. 26 patients were evaluable for response, one patient with pleural mesothelioma achieved a partial response to treatment confirmed by CT scanning. A dose level of 520 mg/m(2)daily x 5 days would be suitable for Phase II testing. Alternative schedules of CT-2584 HMS to overcome the limiting toxicity of malaise would be worthy of examination.  相似文献   
997.
One of the leading causes of death for women is metastatic breast cancer. Because most animal tumors do not accurately model clinical metastatic disease, the development of effective therapies has progressed slowly. In this study, we establish the poorly immunogenic mouse 4T1 mammary carcinoma as a postsurgical animal model. 4T1 growth characteristics parallel highly invasive human metastatic mammary carcinoma and, at the time of surgery, the extent of disease is comparable with human stage IV breast cancer. Progress in understanding the immune response has led to innovative immune-based anticancer therapies. Here, we test in this postsurgical model, a novel cell-based vaccine, combining MHC class II, CD80(B7.1), and SEB superantigen. Effective treatment of tumor-bearing mice with this immunotherapy requires expression of all three molecules. Mean survival time is extended from 5-7.5 weeks for control-treated mice to 6-10.5 weeks for therapy-treated mice. Increased survival is accompanied by a maximum of 100-fold decrease in clonogenic lung metastases. These therapeutic effects are particularly noteworthy because: (a) the postoperative model demonstrates that early metastases responsible for morbidity are established by 2 weeks after tumor inoculation with 7 x 10(3) parental 4T1 cells into the mammary gland; (b) the immunotherapy is started 4 weeks after tumor inoculation when the mice contain extensive, pre-established, disseminated metastases; and (c) CD4+ and CD8+ T cells are required for the effect.  相似文献   
998.
999.
1000.
Erectile dysfunction (ED) is a common problem with a multifactorial aetiology. The treatment of ED has been revolutionised by the introduction of intracavernosal injections some two decades ago. However, the recent development of the orally-administered drug sildenafil (Viagra) has had a major impact on the treatment of ED. We discuss the trials with sildenafil with special reference to cardiovascular risk factors associated with ED.  相似文献   
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