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81.
In the area of drug-eluting stents (DES), complex interventional procedures are increasing in number. In particular, the number of patients undergoing three-vessel or bifurcation lesion stenting is rising, together with increasing concern about the risk of acute stent thrombosis in the area of the DES. In this paper, we present a patient who underwent multivessel bifurcation stent placement after an acute inferior myocardial infarction over a period of one week, with sudden subacute stents thrombosis of the two drug-eluting stents in the left anterior descending and the circumflex coronary arteries, leading to death. This case report is followed by a review of literature.  相似文献   
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83.
This study investigated the effects of a gamma-amino-butyric acid type A (GABAA) receptor agonist and antagonist on morphine-induced locomotor sensitization in male albino mice. Subcutaneous administration to mice of a high dose of morphine (30 mg/kg), but not lower doses (5, 10 and 20 mg/kg) increased locomotion. The maximum locomotor activity was achieved during a 20-min measurement period. The locomotor response to a low dose of morphine (5 mg/kg, subcutaneously) given on day 9 was enhanced in mice pretreated with morphine (7.5, 15 and 30 mg/kg/day x 3 days), indicating that sensitization had developed. Three-day intracerebroventricular (i.c.v.) administration of the GABAA receptor agonist, muscimol (0.025, 0.05, 0.1 and 0.2 microg/mouse/day) significantly decreased both morphine-induced motor stimulation and locomotor sensitization. On the other hand, a 3-day pretreatment with the GABAA-receptor antagonist, bicuculline (0.25, 0.5 and 1 microg/mouse/day) reduced morphine (15 mg/kg)-induced locomotor sensitization. Repeated i.c.v. injections of a lower dose of bicuculline (0.25 microg/mouse/day x 3 days) by itself also decreased morphine-induced locomotion. Furthermore, repeated i.c.v. administration of bicuculline (0.25, 0.5 and 1 microg/mouse/day x 3 days) decreased the effect of i.c.v. injection of muscimol (0.1 microg/mouse/day x 3 days) on locomotor activity induced by morphine (5 mg/kg) in both control and sensitized mice. The magnitude of this response was, however, variable. The results indicate that GABAA receptors might be involved in the acquisition of morphine-induced sensitization.  相似文献   
84.
The effect of intracerebroventricular (i.c.v.) injections of L-arginine, a nitric oxide (NO) precursor and L-NAME, an inhibitor of NO synthase, on retrieval of state-dependent memory induced by LiCl (lithium) was investigated. A one-trial step-down inhibitory avoidance task was used for memory assessment in adult male NMRI mice. Intraperitoneal administration of lithium (10 mg/kg), immediately after training, impaired memory on the test day. Pretest administration of different doses of lithium (5, 10 and 20 mg/kg) reversed the impairment of memory caused by posttraining lithium (10 mg/kg). In addition, pretest administration of L-arginine (0.001, 0.01 and 0.1 microg/mouse, i.c.v.) or L-NAME (0.001, 0.01 and 0.1 microg/mouse, i.c.v.) also reversed amnesia induced by posttraining lithium. Furthermore, pretest coadministration with lithium of a dose of L-arginine (0.0001 microg/mouse, i.c.v.) or L-NAME (0.0001 microg/mouse, i.c.v.) that had no effects when administered alone, increased the effect of lithium on retrieval of inhibitory avoidance memory. The results suggest that NO may have a modulatory role on state-dependent retrieval of inhibitory avoidance memory induced by lithium.  相似文献   
85.
OBJECTIVE: We address the task of inducing explanatory models from observations and knowledge about candidate biological processes, using the illustrative problem of modeling photosynthesis regulation. METHODS: We cast both models and background knowledge in terms of processes that interact to account for behavior. We also describe IPM, an algorithm for inducing quantitative process models from such input. RESULTS: We demonstrate IPM's use both on photosynthesis and on a second domain, biochemical kinetics, reporting the models induced and their fit to observations. CONCLUSION: We consider the generality of our approach, discuss related research on biological modeling, and suggest directions for future work.  相似文献   
86.
Early detection of coronary artery disease (CAD) in women has been challenging. Women are more likely to present with atypical symptoms, and non-invasive evaluation for CAD has been less accurate. Myocardial SPECT imaging is a well-established technique that provides important physiologic, anatomic, and prognostic information in women. Attenuation artifacts secondary to breast tissue are a common problem in women and can lead to decreased specificity of gated SPECT imaging. Cosmetic breast implants are increasing in popularity. The presence of a foreign object overlying the anterior wall of the heart in addition to native breast tissue can significantly increase attenuation artifacts. There is only one report to date describing attenuation artifact due to silicon breast implants in comparison to control, and there are no reports regarding saline breast implants. Here we report three cases of impaired myocardial SPECT imaging in women with breast implants: one patient with silicone implants, and two with saline-containing implants. Clinicians should be aware of this problem and women should be educated regarding the potential future diagnostic problems that may occur with breast implants before considering this cosmetic surgery.  相似文献   
87.
The prevalence of significant pericardial effusion in patients with left ventricular (LV) dysfunction has not been reported. The goal of this study was to evaluate the prevalence and severity of pericardial effusion in patients with decreased fractional shortening (FS) using a large echocardiographic database. A retrospective analysis of 24,265 echocardiograms performed at our institution from 1984 to 1998 was undertaken. FS was measured in 18,015 of the echocardiograms. The occurrence of pericardial effusion was correlated with the degree of FS, and FS was stratified into 4 groups: (1) >25%, (2) 17.5% to 25%, (3) 10% to 17.5%, and (4) <10%. On the basis of visual estimation, effusion was divided into 3 groups: mild, moderate, and severe. Pericardial effusion was present in 1,632 of the echocardiograms in which FS was measured. Pericardial effusion was significantly more common in patients with FS <25% and was correlated with the severity of decreased FS (group 1: 8.4%; group 2: 12.8%; group 3: 13.2%; group 4: 14.4%; p <0.0001). However, when categorizing pericardial effusion by severity, only mild pericardial effusion was correlated with decreased FS (group 1: 6.6%; group 2: 11.0%; group 3: 11.1%; group 4: 14.0%; p <0000.1). Our results indicate that the occurrence of moderate to severe pericardial effusion cannot be explained by a decrease in LV systolic function.  相似文献   
88.
In the present study, the effects of acute and sub-chronic pretreatment of nicotine on impairment of memory formation and the state-dependent learning by morphine have been investigated in mice. Pre-training administration of morphine (5mg/kg) decreased the learning of a one-trial passive avoidance task, which was reversed by pre-test administration of the same dose of morphine. Amnesia induced by pre-training morphine was also significantly reversed in nicotine (0.001, 0.01 and 0.1 mg/kg)-treated animals on the test day. Morphine induced amnesia was also reversed in animals which had previously received sub-chronic injections of nicotine, once daily for 3 days followed by 14 days of no drug treatment. The restoration of memory by pre-test morphine was also reduced in animals which had previously received once daily injections of atropine (0.25, 0.5 and 1 mg/kg, i.p.) for 3 days after 14 of being days drug free. In the animals, restoration of memory by sub-chronic nicotine administration, was also decreased by once daily administration of atropine (0.25, 0.5 and 1 mg/kg) 10 min prior to injection of nicotine (0.1 microg/kg/day, for 3 days) but not with SCH 23390; R(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine HCl (0.01, 0.05 and 0.1 mg/kg) or sulpiride (25, 50 and 100 mg/kg) during 3-days of treatment with nicotine. The results suggest that nicotine may induce sensitization which affects the impairment of memory formation via cholinergic but not dopaminergic systems.  相似文献   
89.
The aim of this study was to compare the efficacy and safety of tramadol versus methadone for treatment of opiate withdrawal. Seventy patients randomly were assigned in two groups to receive either prescribed methadone (60 mg/day) or tramadol (600 mg/day). The withdrawal syndrome of patients was evaluated before and after rapid opiate detoxification using the Objective Opioid Withdrawal Scale (OOWS). No significant differences existed in overall OOWS scores between two groups (P = 0.11). Dropout rates were similar in both groups. Side effects in the tramadol group were as or less common than in the methadone group, with the exception of perspiration. Tramadol may be as effective as methadone in the control of withdrawal and could be considered as a potential substitute for methadone to manage opioids withdrawal.  相似文献   
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