全文获取类型
收费全文 | 14155篇 |
免费 | 679篇 |
国内免费 | 118篇 |
专业分类
耳鼻咽喉 | 95篇 |
儿科学 | 276篇 |
妇产科学 | 408篇 |
基础医学 | 1743篇 |
口腔科学 | 354篇 |
临床医学 | 977篇 |
内科学 | 4025篇 |
皮肤病学 | 242篇 |
神经病学 | 1348篇 |
特种医学 | 583篇 |
外科学 | 2096篇 |
综合类 | 34篇 |
一般理论 | 1篇 |
预防医学 | 506篇 |
眼科学 | 160篇 |
药学 | 714篇 |
中国医学 | 23篇 |
肿瘤学 | 1367篇 |
出版年
2024年 | 12篇 |
2023年 | 89篇 |
2022年 | 200篇 |
2021年 | 410篇 |
2020年 | 209篇 |
2019年 | 298篇 |
2018年 | 389篇 |
2017年 | 290篇 |
2016年 | 326篇 |
2015年 | 367篇 |
2014年 | 555篇 |
2013年 | 707篇 |
2012年 | 982篇 |
2011年 | 1000篇 |
2010年 | 645篇 |
2009年 | 581篇 |
2008年 | 1000篇 |
2007年 | 1006篇 |
2006年 | 912篇 |
2005年 | 960篇 |
2004年 | 861篇 |
2003年 | 787篇 |
2002年 | 707篇 |
2001年 | 104篇 |
2000年 | 97篇 |
1999年 | 116篇 |
1998年 | 148篇 |
1997年 | 116篇 |
1996年 | 135篇 |
1995年 | 87篇 |
1994年 | 100篇 |
1993年 | 80篇 |
1992年 | 75篇 |
1991年 | 61篇 |
1990年 | 54篇 |
1989年 | 45篇 |
1988年 | 32篇 |
1987年 | 22篇 |
1986年 | 37篇 |
1985年 | 32篇 |
1984年 | 30篇 |
1983年 | 23篇 |
1982年 | 34篇 |
1981年 | 34篇 |
1980年 | 32篇 |
1979年 | 21篇 |
1976年 | 11篇 |
1975年 | 9篇 |
1974年 | 10篇 |
1964年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.
Giovina De Rosa Arnerico Testa Maurizio Maurizi Maria Antonietta Satta Claudia Aimoni Alberto Artuso Evelina Silvestri Vittoria Rufini Luigi Troncone 《European journal of nuclear medicine and molecular imaging》1990,17(3-4):179-184
A young woman with a thyroid papillary carcinoma behaving as an autonomously hyperfunctioning nodule is described. Only 17 similar patients have been seen in the past 25 years. It is emphasized that hyperthyroidism does not exclude malignant disease in hot nodules. This possibility suggests that all thyroid nodules, either cold or hot, require careful management. Therefore, in at risk cases, surgery could be the most useful treatment. 相似文献
92.
Paolo Lunardi Michele Acqui Luigi Ferrante Luciano Mastronardi Aldo Fortuna 《Neurosurgical review》1993,16(3):189-196
Between 1953 and 1989 eighty cases of non-traumatic brain abscess were treated in our department. We have re-examined the clinical and neuroradiological features of this pathological process and present our therapeutic approach and results. We believe that the optimal treatment for brain abscess consists of surgical removal.The prognosis for these lesions has undergone a marked improvement over the last two decades in response to neuroradiological, microbiological and surgical advances. The most influential prognostic factor seems to be preoperative clinical status. 相似文献
93.
Sergio Tanganelli Kjell Fuxe Gabriel von Euler Luigi F. Agnati Luca Ferraro Urban Ungerstedt 《Naunyn-Schmiedeberg's archives of pharmacology》1990,342(3):300-304
Summary The interaction of locally perfused cholecystokinin-8 (sulphated) with systemically administered apomorphine was studied on the release of dopamine and its metabolites using microdialysis in the neostriatum of the halothane-anaesthetized male rat. Dialysate levels of dopamine, 3,4-dihydroxyphenylacetic acid and homovanillic acid were assayed by high performance liquid chromatography in combination with electrochemical detection. Perfusion with cholecystokinin-8 (100 M but not 1 M or 10 nM) increased the dialysate levels of dopamine without affecting those of DOPAC or HVA. At low concentrations (1 M and 10 nM but not 1 nM), cholecystokinin-8 counteracted the inhibitory effect of apomorphine (0.05 mg/kg, s. c.) on dopamine release. This counteraction was antagonized by perfusion with the cholecystokinin-8 antagonist proglumide (3 M). At this concentration, proglumide perfused alone was without effect on basal or apomorphine-reduced levels of dopamine. The results indicate a facilitatory effect of cholecystokinin-8 on dopamine release in rat neostriatum only at high concentrations. At lower concentrations, cholecystokinin-8 appears to modulate dopamine release by an inhibitory effect on dopamine autoreceptors possibly involving an intramembrane interaction between presynaptic cholecystokinin-8 receptors and dopamine autoreceptors.
Send offprint requests to K. Fuxe at the above address 相似文献
94.
Crossed aphasia. An update 总被引:2,自引:0,他引:2
Luciano Mastronardi Luigi Ferrante Alberto Maleci Fabrizio Puzzilli Pierpaolo Lunardi Giuseppe Schettini 《Neurosurgical review》1994,17(4):299-304
The aim of this article is to present an update of a rare but interesting problem: crossed aphasia. This term indicates the presence of aphasia after unilateral cerebral lesion of the hemisphere ipsilateral to the patient's dominant hand. We report two cases, review the most relevant literature, and analyze clinical, neuroanatomical, and neurophysiological aspects, taking in consideration the various interpretations proposed to explain this unusual language disorder. 相似文献
95.
Anastomosis 总被引:6,自引:1,他引:5
Romeo Bardini M.D. Massimo Asolati M.D. Alberto Ruol M.D. Luigi Bonavina M.D. Serena Baseggio M.D. Alberto Peracchia M.D. 《World journal of surgery》1994,18(3):373-378
Esophageal anastomosis is still associated with a high rate of complications even though they have decreased considerably in recent years. Anastomotic leaks are more frequent in the neck than in the chest, and related mortality rate is not different. The leakage incidence does not depend on suture materials or on technical modalities used to perform the anastomosis. In fact, there is no difference between the leakage rate when comparing manual and mechanical anastomoses. The leak incidence after both mechanical and manual anastomoses is much higher in collective reviews than in reports coming from leading centers. Frequent esophageal surgeons can learn from their previous experience and therefore avoid technical errors, whereas casual esophageal surgeons do not have this opportunity. Performing an esophageal anastomosis is a technical matter, and suture healing is independent of the patient's biologic situation. Anastomotic fibrotic stricutures are frequent after both manual and mechanical anastomoses, and most can be avoided by meticulous suturing technique.
Resumen La anastomosis esofágica todavía se asocia con una elevada incidencia de complicaciones, a pesar de que éstas han descendido en forma considerable en los últimos años. Las fugas anastomóticas son más frecuentes en el cuello que en el tórax y las tasas de mortalidad no son diferentes. La rata de fuga anastomótica no depende de los materiales de sutura o de las modalidades técnicas que se utilicen para realizar la anastomosis. De hecho no hay diferencia en cuanto a la rata de fugas entre las anastomosis manuales y las mecánicas. La incidencia de fuga, tanto en las manuales como en las mecánicas, es bastante más alta en las revisiones colectivas que en los reportes emanados de los centros médicos de mayor importancia. Los cirujanos especialistas en esófago tienen la posibilidad de aprender de sus experiencias previas y con ello evitar los errores técnicos, en tanto que aquellos cirujanos ocasionales no la poseen. La realización de una anastomosis esofágica es un asunto técnico y la cicatrización de la sutura es independiente de la condición biológica del paciente. Las estrecheces fibróticas de las anastomosis son frecuentes luego de las anastomosis manuales, al igual que luego de las anastomosis mecánicas y la mayoría puede ser evitada mediante una técnica meticulosa.
Résumé Le taux de complications des anastomoses oesophagiennes, même s'il y en a moins ces dernières années, reste toujours élevé. La fréquence de fistules est plus grande quand l'anastomose est faite au cou par rapport au thorax, mais la mortalité n'en est pas très différente. L'incidence de fistules ne dépend ni du matériau de suture ni des modalités d'anastomoses utilisées. Il n'y a aucune différence lorsque les anastomoses manuelles sont comparées aux anastomoses méchaniques: L'incidence des fistules, que ce soit à la main ou à la machine est plus élevée dans les séries collectives par rapport à celle des centres spécialisés. Les chirurgiens qui font des anastomoses de façon régulière ont la possibilité de profiter de leur expérience et ainsi d'éviter les erreurs techniques, alors que le chirurgien occasionnel de l'oesophage n'a pas cette possibilité. L'anastomose oesophagienne est techniquement difficile et la cicatrisation est indépendante de l'état clinique et biologique du patient. Les sténoses fibreuses sont aussi fréquentes après les anastomoses manuelles qu'après les anastomoses méchaniques, mais la plupart peuvent être évitées par une technique méticuleuse.相似文献
96.
K-complexes: are they signs of arousal or sleep protective? 总被引:3,自引:2,他引:1
SUMMARY The number of K-complexes recorded at the central-temporal EEG derivation (C3-T3) during 5 min periods for both the ascending and descending phase of Stage 2 of NREM sleep for cycles 1,2… etc. were counted in 10 subjects for each of the following five groups: normal persons, patients with a primary generalized form of epilepsy, narcolepsy, insomnia and obstructive sleep apnoea. The differences in time spent in different stages of sleep were as expected for these types of patients. A 2-within, 1-between factors, repeated measure ANOVA was applied to the data on K-complexes. Overall, there was no significant difference between the number of K-complexes observed during the ascending and descending phases of the different sleep cycles. Patients with a sleep disorder had significantly less well-defined K-complexes than the normals and the patients with a primary form of generalized epilepsy: for insomnia ( P = 0.035), for apnoea ( P = 0.011) and for narcolepsy ( P = 0.001). There was a significant, but very low correlation coefficient between the number of K-complexes observed during Stage 2 of NREM sleep and the time spent during that stage for all groups combined (Rho 0.27, P = 0.002) and for the narcoleptic patients (Rho 0.44, P = 0.017). In all, the findings lend support to the hypothesis that a K-complex can be seen as a 'defensive response', or has a sleep protective function. 相似文献
97.
Two cases of intradural cavernous angioma of the cauda equina are reported, one of which presented with symptoms of subarachnoid hemorrhage. The clinical and therapeutic aspects of intradural angiomas, in particular those of the cauda equina, are discussed. 相似文献
98.
Alleva E Cirulli F Calamandrei G Rondinini C Capirci O Aloe L Volterra V 《Annali dell'Istituto superiore di sanità》1999,35(2):211-219
Williams syndrome (WS) is a rare (2-5/100,000) genetic human disorder characterised by a typical facies and mental retardation with a deficit in the visuospatial cognitive function and a relative preservation of linguistic abilities in general, and spoken language in particular. This syndrome also includes morphological anomalies, metabolic functional impairments, and likely deficits in the pattern of brain ontogenesis. The genetic basis of WS, recently identified, are presented. A cognitive profile of the WS individuals is defined and compared to Down syndrome (DS) and autism cognitive profiles. Neuroanatomical features of WS, including a reduction in brain volume, preservation of cerebellum and frontal lobes, and a reduction of posterior cortical systems, are described. The possible role of NGF (nerve growth factor)--a neurotrophin involved in the development of brain cholinergic systems and the associated behavioural functions--in the aetiology of the typical mental retardation of WS patients, is critically discussed. Future research avenues, including the identification of potential neurobiological markers in order to precociously diagnose this syndrome, are reviewed. 相似文献
99.
Varrassi G Marinangeli F Agrò F Aloe L De Cillis P De Nicola A Giunta F Ischia S Ballabio M Stefanini S 《Anesthesia and analgesia》1999,88(3):611-616
We assessed the relative morphine consumption in a combined analgesic regimen (on-demand morphine plus the nonopioids propacetamol or ketorolac) after gynecologic surgery. Two hundred women randomly received two i.v. doses of propacetamol 2 g or ketorolac 30 mg in a double-blinded, double-dummy trial. Patients were monitored for 12 h, and the following efficacy variables were assessed: total dose of morphine, pain intensity, and global efficacy. Safety and tolerability were evaluated by the occurrence of adverse events, especially the presence and intensity of gastrointestinal symptoms. Hemostatic variables were measured 30 and 60 min after the first infusion; arterial blood pressure, heart and respiratory rates, sedation scores, and renal and hepatic function were also assessed. Total morphine requirements were not significantly different between the propacetamol (10.6 +/- 4.8 mg) and ketorolac (10.2 +/- 4.4 mg) groups. The evolution of pain intensity and the global efficacy also showed similar patterns in the two groups: 70.2% of patients in the propacetamol group rated the efficacy as "good/ excellent" compared with 68.2% in the ketorolac group. There were no clinically significant changes in vital signs or laboratory values and no observed differences between the two groups, although ketorolac slightly, but not significantly, prolonged the bleeding time. Epigastric pain was present in 9% and 15% of patients receiving propacetamol and ketorolac, respectively. There were two adverse events in the propacetamol group and four in the ketorolac group. Propacetamol demonstrates an efficacy similar to that of ketorolac and has an excellent tolerability after gynecologic surgery. IMPLICATIONS: Propacetamol and ketorolac, combined with patient-controlled analgesia morphine, show similar analgesic efficacy after gynecologic surgery. Morphine consumption and pain scores were comparable in the two studied groups. Propacetamol is as effective as ketorolac and has an excellent tolerability after gynecologic surgery. 相似文献
100.
Cost comparison of sevoflurane with isoflurane anesthesia in arthroscopic menisectomy surgery 总被引:1,自引:0,他引:1
Craig R. Ries Aliréza Azmudéh Luigi G. Franciosi Stephan K. W. Schwarz Bernard A. MacLeod 《Journal canadien d'anesthésie》1999,46(11):1008-1013
PURPOSE: To determine the "real world" cost of sevoflurane compared with isoflurane in balanced general anesthesia for daycare arthroscopic menisectomy, we prospectively investigated perioperative drug requirement and expense as well as recovery time. METHODS: Following intravenous induction, 40 consenting adult patients randomly received either sevoflurane- or isoflurane-based anesthesia with a standardized gas inflow rate of 3 l x min. Recovery was assessed in the postanesthetic recovery room (PARR) in a double-blind manner at 15 min intervals using the Aldrete scoring system until patients met discharge criteria. RESULTS: Patient demographics, anesthetic duration, volatile potency and adjunct drug requirements were similar in the two groups. Total perioperative drug cost per patient was CAN$38.10+/-10.13 (mean +/- SD) for the sevoflurane group and $23.87+/-6.59 for the isoflurane group (P<0.01). Although the nonvolatile drug cost was comparable between the two groups, the volatile drug cost per patient was $19.40+/-8.80 for sevoflurane and $4.50+/-1.90 for isoflurane (P<0.01). This four-fold sevoflurane-to-isoflurane cost difference was the product of two ratios, both based on the volume of liquid anesthetic: the ratio of consumption, 2.1; and the ratio of institutional price, 2.1. Intraoperative hemodynamic response, time until discharge from the PARR and incidences of postoperative nausea and vomiting did not significantly differ between the two groups. CONCLUSIONS: When used to maintain equipotent balanced general anesthesia for daycare arthroscopic menisectomy, volatile consumption and cost were greater for sevoflurane compared with isoflurane. Nonvolatile perioperative drug cost and recovery times were similar, however, in the two groups. 相似文献