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Paediatricians may be called on to see a suicidal child or adolescent in the emergency department as a psychiatric consultation is not always immediately available. The paediatrician will then play a pivotal role in the evaluation and disposition of the patient.(1) American reports have shown that 8% of high school students have made a suicidal attempt and that 2% had made an attempt that required medical attention.(2) Suicidal attempts account for 12% of all emergency department visits for the adolescent age group.(3) In the U.K. overdoses account for 4.7% of all general hospital admission in those aged 12-20 years. (4) In Republic of Ireland the most recent national vital statistics data revealed that over a period of one year July'97 - July '98, more than 650 children and adolescents were admitted to hospital with the deliberate self poisoning. The female to male ratio was 3:1.(7) 相似文献
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Motor vehicle driver injury and socioeconomic status: a cohort study with prospective and retrospective driver injuries 下载免费PDF全文
Whitlock G Norton R Clark T Pledger M Jackson R MacMahon S 《Journal of epidemiology and community health》2003,57(7):512-516
STUDY OBJECTIVE: To investigate the association between motor vehicle driver injury and socioeconomic status. DESIGN: Cohort study with prospective and retrospective outcomes. SETTING: New Zealand. PARTICIPANTS: 10 525 adults (volunteer sample of a multi-industry workforce, n=8008; and a random sample of urban electoral rolls, n=2517). Outcome measure: Motor vehicle driver injury resulting in admission of the driver to hospital or the driver's death, or both, during the period 1988-98; hospitalisation and mortality data were obtained by record linkage to national health databases. Main results: After adjustment for age and sex, driver injury risk was inversely associated with both occupational status (p for linear trend <0.0001) and educational level (p for linear trend =0.007). Participants in the lowest approximate quartile of occupational status were four times as likely (HR 4.17, 95% CI 2.31 to 7.55) to have experienced a driver injury during follow up as participants in the highest approximate quartile. Participants who had been to secondary school for less than two years were twice as likely (HR 2.26, 95% CI 1.34 to 3.81) to have experienced a driver injury as those who had been to university or polytechnic. There was little evidence that driver injury risk was associated with neighbourhood income (p for linear trend =0.12) CONCLUSIONS: Occupational status and educational level seem to be important determinants of driver injury risk. Driver injury countermeasures should be targeted to people in low status occupations, as well as to people with comparatively little formal education. 相似文献
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Harrap SB Tzourio C Cambien F Poirier O Raoux S Chalmers J Chapman N Colman S Leguennec S MacMahon S Neal B Ohkubo T Woodward M;PROGRESS Collaborative Group 《Hypertension》2003,42(3):297-303
The insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene might have consequences for the risks of vascular diseases. We examined the ACE genotype and the effects of a perindopril-based blood pressure-lowering regimen on macrovascular events, dementia, and cognitive decline among hypertensive and nonhypertensive patients with a history of cerebrovascular disease. ACE I/D genotypes were measured in 5688 of 6105 individuals with previous stroke or transient ischemic attack who participated in the PROGRESS trial. The DD genotype was significantly (P<0.0001) less frequent in Asian subjects (Chinese and Japanese, 14.7%) than in non-Asian subjects (32.0%). Controlling for racial background, there were no associations between ACE genotypes and cerebrovascular disease history or cardiovascular risk factors, including baseline blood pressure. The ACE genotype was not associated with the long-term risks of stroke, cardiac events, mortality, dementia, or cognitive decline; neither did the ACE genotype predict the blood pressure reduction associated with the use of the ACE inhibitor perindopril. Similarly, there was no evidence that the ACE genotype modified the relative benefits of ACE inhibitor-based therapy over placebo. This study provides no evidence that in patients with cerebrovascular disease, knowledge of ACE genotype is useful for predicting either the risk of disease or the benefits of perindopril-based blood pressure-lowering treatment. 相似文献
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A new low-dose formulation of selegiline: clinical efficacy,patient preference and selectivity for MAO-B inhibition 总被引:2,自引:0,他引:2
Clarke A Johnson ES Mallard N Corn TH Johnston A Boyce M Warrington S MacMahon DG 《Journal of neural transmission (Vienna, Austria : 1996)》2003,110(11):1257-1271
Summary. Three studies were performed using a fast dissolving formulation of selegiline hydrochloride designed for buccal absorption Zydis Selegiline. The aim of the first study was to compare the therapeutic efficacy of Zydis Selegiline (1.25mg or 10mg) with conventional selegiline hydrochloride tablets conventional selegiline tablets (10mg) in patients with Parkinsons disease (PD) who were previously treated with conventional selegiline tablets as an adjunct to levodopa/dopamine agonist therapy. Patients were observed for 4 weeks to ensure that they were stable. Stable patients (n=197) were then randomised to continue with conventional selegiline tablets 10mg (n=68), or to treatment with Zydis Selegiline 1.25mg (n=64) or Zydis Selegiline 10mg (n=62) for 12 weeks in this randomised, parallel group study. A further aim was to establish the acceptability of Zydis Selegiline compared with conventional selegiline tablets. Patient preference for Zydis Selegiline was also evaluated in a second study, a single-dose, randomised, two-way crossover study conducted in patients with PD (n=148). Patients were stratified by the presence or absence of swallowing and salivation problems and were randomised to either Zydis Selegiline 5mg or a placebo fast-dissolving formulation. In a third study, the degree of potentiation of the tyramine pressor effect following Zydis Selegiline was compared with that following conventional selegiline tablets in healthy volunteers. A total of 24 healthy volunteers were randomised to receive Zydis Selegiline 1.25mg or conventional selegiline tablets 10mg for 14–16 days in an open-label, randomised parallel group study.Both Zydis Selegiline (1.25mg and 10mg) treatments were shown to be therapeutically equivalent to conventional selegiline tablets 10mg based on comparison of mean total Unified Parkinsons Disease Rating Scale (UPDRS) scores. Therapeutic equivalence was defined a priori as the 90% confidence interval (CI) for the difference in total UPDRS scores between groups to lie entirely within the range ±5. The difference (90% CI) in mean adjusted total UPDRS between Zydis Selegiline 1.25mg and conventional selegiline tablets 10mg was –2.50 (–4.84, –0.17), and for Zydis Selegiline 10mg and conventional selegiline tablets 10mg, 0.04 (–2.30, 2.38). For the motor subscores of the UPDRS, differences between adjusted means (90% CI) compared with the conventional selegiline tablets group were: Zydis Selegiline 1.25mg, –2.14 (–3.94, –0.33) and Zydis Selegiline 10mg, –0.90 (–2.70, +0.91). Patients who switched from conventional selegiline tablets to Zydis Selegiline 1.25mg showed a slight improvement in UPDRS scores following 12 weeks of treatment (standard error of difference 1.039; p=0.01).In the single-dose crossover study, most (61%) patients liked Zydis Selegiline 5mg; a significantly greater proportion than the null hypothesis of 50% (p<0.002). However, only 62 patients (46%) indicated that they liked the taste of Zydis Selegiline. Nevertheless, the proportion of patients who preferred Zydis Selegiline (65%) to their usual medication was significantly greater than the null hypothesis of 50% (p<0.001).Similar findings were demonstrated in the 12-week study where a higher proportion of patients who received up to 3 months of treatment indicated a preference for either Zydis Selegiline 1.25mg (90%) or Zydis Selegiline 10mg (86%) over conventional selegiline tablets 10mg. More than 90% of patients found Zydis Selegiline easy to take, with 61% rating it as extremely easy. Most (81%) patients taking Zydis Selegiline 1.25mg liked the taste compared with 45% taking Zydis Selegiline 5mg (in the previous study).Zydis Selegiline did not potentiate the tyramine effect: a pressor effect was elicited after 400mg tyramine both before and after 14 days of treatment with Zydis Selegiline 1.25mg. In contrast, after 14 days treatment with conventional selegiline tablets 10mg, the threshold dose required to elicit the tyramine pressor response was significantly (p<0.0001) reduced from 400mg to 200mg.In summary, Zydis Selegiline at doses of 1.25mg and 10mg was therapeutically equivalent to conventional selegiline tablets 10mg. The Zydis Selegiline formulation was well-liked by all patients, with most preferring Zydis Selegiline 1.25mg to their usual selegiline tablet. Furthermore, Zydis Selegiline was well tolerated and, unlike conventional selegiline tablets, appeared to retain specificity for inhibition of monoamine oxidase type B (MAO-B), since it did not potentiate the pressor response to tyramine.Present address: Cephalon UK Ltd., Surrey Research Park, Guildford, United KingdomPresent address: Safetymednet, Ruscombe, United KingdomPresent address: Oxford Glycosciences (UK) Ltd., Abingdon, United KingdomReceived December 3, 2002; accepted July 23, 2003 相似文献
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MacMahon M Kirkpatrick C Cummings CE Clayton A Robinson PJ Tomiak RH Liu M Kush D Tobert J 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2000,10(4):195-203
BACKGROUND AND AIM: This study was conducted in preparation for the Study Evaluating Additional Reduction in Cholesterol and Homocysteine (SEARCH). SEARCH is a 12,000 patient 2X2 factorial study in post-myocardial infarction patients that will compare simvastatin 20 mg with simvastatin 80 mg to evaluate whether greater LDL-C reductions with simvastatin provide greater coronary event reductions. SEARCH will also test the hypothesis that lowering plasma homocysteine with folic acid and vitamin B12 will reduce coronary events. This pilot study was performed to determine whether any clinically meaningful interaction between simvastatin and folic acid/vitamin B12 exists. METHODS AND RESULTS: Following a 2-week diet/placebo run-in period, 141 patients with primary hypercholesterolaemia were randomised to one of three treatments for 6 weeks: 80 mg/day simvastatin and 2 mg folic acid/0.8 mg vitamin B12 daily (combination group); or 80 mg/day simvastatin and placebo vitamins (simvastatin alone group); or 2 mg folic acid/0.8 mg vitamin B12 daily and placebo simvastatin (vitamins alone group). The combination group and simvastatin alone group experienced similar serum lipid changes with reductions in LDL-cholesterol of 55.2% and 51.5% respectively. The combination group and vitamins alone group experienced similar homocysteine lowering with reductions in homocysteine of 25.3% and 23.1% respectively. All therapies were well tolerated. CONCLUSIONS: There was no detectable antagonistic effect when simvastatin and folic acid/vitamin B12 were administered concomitantly. 相似文献
49.
This report describes systemic-to-pulmonary venous connections at the pleural level resulting from superior vena cava occlusion. The interval development of new venous collaterals within a 3-year period represents an advanced manifestation of SVC occlusion in this patient with a history of pleural disease. In this case, progressive venous thrombosis caused by underlying hypercoaguability led to the development of collaterals in unusual sites, including systemic-to-pulmonary venous shunting, and resulting in progressive cyanosis and death. 相似文献
50.
Nordholm AF Rossi J Ritchie GD McInturf S Hulme ME McCool C Narayanan L MacMahon KL Eggers J Leahy HF Wolfe RE 《Journal of toxicology and environmental health. Part A》1999,56(7):471-499
Thirty-two Sprague-Dawley rats were exposed for 6 h/d for 14 consecutive days to JP-4 jet fuel vapor (2 mg/L) or room air control conditions. Following a 14- or 60-d recovery period, rats completed a battery of 8 tests selected from the Navy Neurobehavioral Toxicity Assessment Battery (NTAB) to evaluate changes in performance capacity. Exposure to JP-4 vapor resulted in significant changes in neurobehavioral capacity on several tests that varied as a function of the duration of the recovery period. Rats were evaluated for major neurotransmitter and metabolite levels in five brain regions and in the blood serum. Levels of 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) were shown to be significantly elevated in several brain regions as well as in the blood serum in the vapor-exposed groups. Results of the rat study are compared to previously reported neurobehavioral evaluations of European manufacturing personnel exposed chronically to jet fuel vapor. 相似文献