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81.
82.
Ajoene (CAS 92284-99-6), an organic trisulphur originally isolated from garlic, has an antimycotic activity which has been widely demonstrated both in vitro and in vivo. The objective of this work was to compare the safety and effectiveness of ajoene (0.6%, gel) with terbinafine (CAS 91161-71-6) (1%, cream) for the treatment of tinea corporis and tinea cruris. The patients selected were 60 soldiers with clinical and mycological diagnosis of either dermatophytosis. They were distributed at random in two treatment groups, one treated with ajoene at 0.6% and the other with terbinafine at 1%. All patients were evaluated clinically and mycologically 30 and 60 days after completion of the treatment, which was considered effective when clinical signs and symptoms had disappeared and the mycological cultures were negative. Thirty days after treatment, the percent healing rate was 77 and 75 for the groups treated with ajoene and terbinafine, respectively. Sixty days after treatment, the healing rate 73% and 71% for the groups treated with ajoene and terbinafine, respectively. These results and those obtained in previous studies confirm that ajoene is a new agent for the topic treatment of superficial mycoses, and for the first time show the therapeutic usefulness of an inhibitor of phospholipids biosynthesis in eukaryotes.  相似文献   
83.
Background: There is conclusive evidence from large scale randomized clinical trials (RCTs) that several treatments administered in the acute phase of a myocardial infarction (AMI) reduce mortality. However, only a minority of patients admitted with AMI receives at the appropriate treatments. Objectives: This study aims at (1) describe the utilization patterns for AMI; (2) determine the appropriateness of prescribing, measured as adherence to the ACC/AHA guidelines; and (3) determine which factors are associated with the administration of thrombolytic agents. Methods: The study was a multi-center survey carried out in ten countries (nine European and one Canadian province) over a 3-month period. Data were prospectively collected by clinical pharmacists. All consecutive patients admitted to the participating hospitals during the study period with a diagnosis of suspected AMI were included in the study. Rates of use were calculated as “overall utilization” and “adjusted utilization” (e.g., accounting for eligibility). Results: Data were available on 1976 patients from 56 participating centers. The mean age of the patients was 65 years (range 25–95, SD = 12.6) and 29.7% were women. Adjusted utilization rates were 63.7% for thrombolysis, 88% for aspirin, and 65.9% for β-adrenergic blocking agents. The most utilized thrombolytic agent was streptokinase (65.9%). The main reasons given by physicians for not administering thrombolysis was the delay from chest pain onset to admission. Patients admitted to teaching hospitals were less likely to receive aspirin than patients admitted to general hospitals (adjusted rate 90.1% vs 86%, P = 0.007), but they were more likely to undergo a primary invasive procedure (11.0% vs 2.5% P = 0.001). Multivariate analysis showed that age greater than 74 years, delay, prior myocardial infarction, and Killip scale were correlated with the non-utilization of thrombolysis. Conclusion: Recommended treatments are still underutilized in patients with AMI. Increased utilization is required, particularly for elderly people. There is a wide variability among hospitals with different affiliations (teaching vs non teaching), demonstrating the different patterns of practice in various settings. Received: 2 February 1998 / Accepted in revised form: 8 August 1998  相似文献   
84.
The present study was designed to investigate the possibility of activation of GABA(B) receptors during the motor inhibition caused by cannabimimetics. Adult male rats were injected with an acute dose of arachidonylethanolamide (AEA), Delta(9)- tetrahydrocannabinol (THC), beclofen or vehicle, after pretreatment with CGP 35348, a specific antagonist for GABA(B) receptors, or vehicle, and the behavioral response produced by these compounds tested in an open field. As expected, the administration of either AEA or THC produced a very pronounced motor inhibition, reflected by decreased ambulation and increased time spent in inactivity. The administration of baclofen also produced a marked motor deficit, with similar changes to those observed with both cannabimimetics. Pretreatment with the GABA(B) antagonist, CGP 35348, prevented the motor inhibition induced by baclofen and also attenuated the motor deficit caused by both cannabimimetics, suggesting a role for this receptor. In summary, a GABAergic influence, acting through GABA(B) receptors, seems to be involved in mediating motor effects of cannabimimetics, since the blockade of these receptors attenuates cannabimimetic-induced signs of motor inhibition.  相似文献   
85.
Treatment of retinitis by cytomegalovirus (CMV) in AIDS patients requires frequent repetitive injections of intravitreal ganciclovir (GCV). This study was undertaken to establish experimentally whether the intravitreal application of liposomally-entrapped GCV could prolong intraocular therapeutic levels when compared with the intravitreal injection of free GCV, and the clinical effectiveness of this approach in AIDS patients. Intraocular concentration of GCV was determined by means of an ELISA test in rabbit vitreous 2, 3, 7, and 14 days after a single intravitreal injection of either different doses of the free drug (0.2–20 mg) or 1 mg of liposomally-entrapped GCV. After 72 h, only the vitreous of rabbits injected with doses of free GCV greater than or equal to 5 mg showed therapeutic levels of the drug; no GCV was detected after 72 h with any of the doses applied. Moreover, the microscopic study revealed GCV-induced damage in retinal structures in the animals injected with a free GCV dose greater than or equal to 15 mg. Intravitreal injection to rabbits of 1 mg of liposomally-encapsulated GCV showed no retinal toxicity at any of the time points studied, and therapeutic levels were detected up to 14 days after injection (4.67 ± 0.39 g/ml). Five AIDS patients suffering CMV retinitis were injected with 0.5 mg of liposomally-entrapped GCV (2 mg of lecithin). Complete remission of the CMV retinitis was observed already at the third injection of 0.5 mg GCV (one per week) and relapse did not occur during the 2–4 month follow-up of the patients. In view of the results presented, it can be concluded that intravitreal injection of liposomally-encapsulated GCV increases the time period required for reinjections in the treatemnt of CMV retinitis.Abbreviations AIDS acquired immunodeficiency syndrome - AZT zidovudine - CMV cytomegalovirus - GCV ganciclovir  相似文献   
86.
OBJECTIVE: To determine the association between mortality from violent or firearm related injury and previous handgun purchase. METHODS: Case-control study of 213 466 Californians ages 21 and older who died in 1998; cases were the 4728 violent or firearm related injury deaths, with subsets by specific cause and means of death, and controls were the 208 738 non-injury deaths. The exposure of interest was the purchase of a handgun during 1996-98. The main outcome measure was the odds ratio for handgun purchase, adjusted for age, sex, race, education, and marital status. RESULTS: Handgun purchase was more common among persons dying from suicide (odds ratio (OR) 6.8; 95% confidence interval (CI) 5.7 to 8.1) or homicide (OR 2.4, 95% CI 1.6 to 3.7), and particularly among those dying from gun suicide (OR 12.5; 95% CI 10.4 to 15.0) or gun homicide (OR 3.3; 95% CI 2.1 to 5.3), than among controls. No such differences were seen for non-gun suicide or homicide. Among women, those dying from gun suicide were much more likely than controls to have purchased a handgun (OR 109.8; 95% CI 61.6 to 195.7). Handgun purchasers accounted for less than 1% of the study population but 2.4% of gun homicides, 14.2% of gun suicides, and 16.7% of unintentional gun deaths. Gun suicide made up 18.9% of deaths among purchasers but only 0.6% of deaths among non-purchasers. CONCLUSION: Among adults who died in California in 1998, those dying from violence were more likely than those dying from non-injury causes to have purchased a handgun.  相似文献   
87.
Novel noninvasive techniques for studying renal function in man   总被引:3,自引:0,他引:3  
Renal artery stenosis is a major cause of renovascular hypertension in humans, and may lead to ischemic nephropathy and end-stage renal disease. The mechanisms responsible for the progressive renal functional and structural alterations have not been fully elucidated, partly because of the lack of reliable, noninvasive techniques capable of quantifying renal regional hemodynamics and function distal to a stenosis in the renal artery. Novel imaging tools now enable quantification of concurrent intrarenal (cortical and medullary) hemodynamics, segmental nephron dynamics (intratubular transit times and fluid concentrations), and renal function in the intact kidney. Fast computed tomography (CT) scanners, such as electron beam CT, allow discrimination of subtle alterations in renal perfusion and segmental nephron function consequent to changes in renal perfusion pressure, both within and below the range of renal blood flow autoregulation. This technique provides an opportunity to define intrarenal perfusion patterns and function in animals and patients with renal artery stenosis, and may provide insight into the effects of chronic unilateral or bilateral renovascular disease on both the hypoperfused and contralateral kidneys. This methodology may thereby prove to be very useful in the evaluation of renal disease in general, and the renovascular hypertensive patient in particular.  相似文献   
88.
VN2222 (1-(benzo[b]thiophen-3-yl)-3-[4-(2-methoxiphenyl piperazin-1-yl]propan-1-ol) is a potential antidepressant with high affinity for the serotonin transporter and 5-HT(1A) receptors. Locally applied, VN2222 enhanced the extracellular 5-hydroxytryptamine (5-HT) concentration (5-HT(ext)) in rat striatum to 780% of baseline whereas its systemic administration (1-10 mg/kg s.c.) reduced 5-HT(ext). In the presence of citalopram, 8-OH-DPAT or VN2222 applied in medial prefrontal cortex reduced 5-HT(ext). Fluoxetine, VN2222, and 8-OH-DPAT suppressed the firing rate of dorsal raphe 5-HT neurons (ED(50): 790, 14.9, and 0.8 microg/kg i.v., respectively). These effects were antagonized by WAY 100635. Administration of VN2222 for 2 weeks desensitized 5-HT(1A) receptors as assessed by microdialysis and single-unit recordings (ED(50) values for 8-OH-DPAT were 0.45 and 2.34 microg/kg i.v. for controls and rats treated with 6 mg/kg day VN2222). These results show that VN2222 is a mixed 5-HT reuptake inhibitor/5-HT(1A) agonist that markedly desensitizes 5-HT(1A) autoreceptors. These properties suggest that it may be a clinically effective dual action antidepressant drug.  相似文献   
89.
Morphological changes in the Buffalo Green Monkey (BGM) cell line after exposure to a subcytotoxic dose (0.062 mM, equivalent to EC(10)-effective concentration 10%) of cadmium chloride have been evaluated. Cells were exposed for 24 h and the effects observed at the ultrastructural level by transmission and scanning microscopy. Using transmission electron microscopy, the most notable findings in treated cells were the presence of intranuclear inclusion bodies and thin intracytoplasmic granules associated to myelin figures and the presence of apoptotic bodies. Other morphological alterations included cell vacuolisation and a reduced cytoplasm volume, condensation of the mitochondria and a decreased number of cytoplasmic organelles, except lysosomes and autophagic vacuoles, which increased in number. Scanning electron microscopy pointed to a cell with a disrupted perinuclear region and a decrease in the number of surface microvilli. We conclude that the BGM cell line may be considered an useful tool for toxicological studies involving cadmium.  相似文献   
90.
Among the neoplasias affecting the scrotum and other elements contained within, testicular tumours are the most common; paratesticular neoplasias account for about 2%. 70% of them are benign tumours, lipoma being one the most frequent types. We contribute a new case of paratesticular lipoma in a 45-year old patient, who presented with scrotal complaints. Physical examination found fibroelastic scrotal tumoration; diagnosis being aided with ultrasound and CAT that showed fat tissue radiographic patterns. Complete removal of tumoration and subsequent pathoanatomical study confirmed the diagnosis of paratesticular lipoma. A literature review on the subject is included with reflections on the clinical, diagnostic and therapeutical aspects.  相似文献   
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