全文获取类型
收费全文 | 220499篇 |
免费 | 17631篇 |
国内免费 | 7080篇 |
专业分类
耳鼻咽喉 | 1256篇 |
儿科学 | 7659篇 |
妇产科学 | 1550篇 |
基础医学 | 19484篇 |
口腔科学 | 3609篇 |
临床医学 | 23350篇 |
内科学 | 55915篇 |
皮肤病学 | 2717篇 |
神经病学 | 26137篇 |
特种医学 | 6326篇 |
外国民族医学 | 4篇 |
外科学 | 16798篇 |
综合类 | 30054篇 |
现状与发展 | 31篇 |
一般理论 | 9篇 |
预防医学 | 18709篇 |
眼科学 | 2391篇 |
药学 | 15270篇 |
191篇 | |
中国医学 | 10008篇 |
肿瘤学 | 3742篇 |
出版年
2024年 | 653篇 |
2023年 | 4650篇 |
2022年 | 8354篇 |
2021年 | 11841篇 |
2020年 | 11099篇 |
2019年 | 8388篇 |
2018年 | 8327篇 |
2017年 | 8246篇 |
2016年 | 8554篇 |
2015年 | 8251篇 |
2014年 | 15608篇 |
2013年 | 17038篇 |
2012年 | 12743篇 |
2011年 | 13799篇 |
2010年 | 10858篇 |
2009年 | 10438篇 |
2008年 | 10444篇 |
2007年 | 10105篇 |
2006年 | 8997篇 |
2005年 | 7424篇 |
2004年 | 6313篇 |
2003年 | 5426篇 |
2002年 | 4581篇 |
2001年 | 3951篇 |
2000年 | 3299篇 |
1999年 | 2823篇 |
1998年 | 2704篇 |
1997年 | 2382篇 |
1996年 | 2134篇 |
1995年 | 1929篇 |
1994年 | 1775篇 |
1993年 | 1515篇 |
1992年 | 1454篇 |
1991年 | 1278篇 |
1990年 | 1012篇 |
1989年 | 858篇 |
1988年 | 805篇 |
1987年 | 732篇 |
1986年 | 633篇 |
1985年 | 736篇 |
1984年 | 617篇 |
1983年 | 380篇 |
1982年 | 446篇 |
1981年 | 374篇 |
1980年 | 282篇 |
1979年 | 247篇 |
1978年 | 184篇 |
1977年 | 164篇 |
1976年 | 135篇 |
1975年 | 49篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
目的:探讨血清尿酸(UA)水平与冠心病(CHD)及其相关因素关系。方法:选择经冠状动脉造影检查证实的冠心病患者187例,冠脉造影正常对照组71例,常规空腹采集静脉血测定血清UA,分析冠心病危险因子、冠状动脉病变程度、病变支数及病变类型与相应UA水平的关系。结果:CHD组的一般资料与对照组无明显差异,但血清UA水平明显高于对照组(P<0.01);在CHD组中,轻度狭窄、中度狭窄及重度狭窄,其UA水平逐渐增高,分别为(418.92±36.52),(450.84±48.65),(487.40±51.62)μmol/L(P<0.01);单支病变、双支病变和三支病变,其UA水平也增高,分别为(426.32±30.78),(455.24±35.34),(480.40±40.12)μmol/L(P<0.01);A、B和C型病变,其UA水平依次增高,分别为(425.85±35.71),(461.65±46.50),(493.41±53.24)μmol/L(P<0.01);结论:血清UA水平的增高与冠心病密切相关,是冠心病发病的危险因素。 相似文献
992.
Christopher D Herzog Biplob Dass James E Holden James Stansell Mehdi Gasmi Mark H Tuszynski Raymond T Bartus Jeffrey H Kordower 《Movement disorders》2007,22(8):1124-1132
Neurturin (NTN) is a potent survival factor for midbrain dopaminergic neurons. CERE-120, an adeno-associated virus type 2 (AAV2) vector encoding human NTN (AAV2-NTN), is currently being developed as a potential therapy for Parkinson's disease. This study examined the bioactivity and safety/tolerability of AAV2-NTN in the aged monkey model of nigrostriatal dopamine insufficiency. Aged rhesus monkeys received unilateral injections of AAV2-NTN into the caudate and putamen, with each animal therefore serving as its own control. Robust expression of NTN within the nigrostriatal system was observed 8 months postadministration. (18)F-fluorodopa imaging using positron emission tomography revealed statistically significant increases in (18)F-fluorodopa uptake in the injected striatum compared with the uninjected side at 4 and 8 months. In addition, at 8 months postadministration, a significant enhancement in tyrosine hydroxylase immunoreactive fibers and an increase in the number of tyrosine hydroxylase immunoreactive cells was observed in the AAV2-NTN injected striatum compared with the uninjected side. Robust activation of phosphorylated extracellular signal-regulated kinase immunoreactivity in the substantia nigra was also observed. Histopathological analyses revealed no adverse effects of AAV2-NTN in the brain. Collectively, these results are consistent with the neurotrophic effects of NTN on the dopaminergic nigrostriatal system and extend the growing body of evidence supporting the concept that AAV2-NTN may have therapeutic benefit for Parkinson's disease. 相似文献
993.
Joaquim Ferreira MD João Maia Silva MD Rita Freire BS João Pignatelli MD Leonor Correia Guedes MD Alexandra Feijó MD Mário Miguel Rosa MD Miguel Coelho MD João Costa MD Ana Noronha BS Russell Hewett MD A. Marques Gomes PhD J.L. Cirne de Castro MD Olivier Rascol PhD Cristina Sampaio PhD 《Movement disorders》2007,22(10):1471-1475
Our objective was to evaluate the frequency of neoplastic and preneoplastic skin lesions in Parkinson's disease (PD) patients when compared with an aged-matched population. We performed a cross-sectional survey in PD patients and in an age-matched control group. Patients and controls were examined by a movement disorder specialist and a dermatologist. 150 PD patients and 146 controls were included. Thirty-five PD patients (23.3%) presented skin lesions that could be classified as neoplastic or preneoplastic vs. 20 subjects in the control group (13.7%) (OR 95%, CI 1.92 [1.05, 3.51]). However, this difference lost statistical significance when adjusted for gender (recruitment of controls was matched just for age with an over representation of males in the PD group). Twenty-nine PD patients (19%) presented actinic keratosis and basal cell carcinoma was diagnosed in 4 patients (3%). Although nonconclusive, our results are in agreement with previous studies suggesting an increased risk of skin cancer in PD patients. The frequency of actinic keratosis in PD patients and the associated risk to develop melanoma recommends its screening in future epidemiological studies. 相似文献
994.
Nir Giladi Babak Boroojerdi Amos D Korczyn David J Burn Carl E Clarke Anthony H V Schapira 《Movement disorders》2007,22(16):2398-2404
Rotigotine is a new, non-ergot dopamine agonist formulated in a transdermal delivery system. The present study was to investigate the efficacy and safety of the rotigotine transdermal patch in the treatment of early Parkinson's disease. Patients (n = 561) were randomized to rotigotine, ropinirole, or placebo. The titration period was up to 13 weeks, and there was a minimum dose-maintenance period of 24 weeks for ropinirole and 33 weeks for rotigotine. The primary endpoint was the proportion of patients with a minimum of 20% decrease in the combined Unified Parkinson's Disease Rating Scale Part II and Part III scores. The responder rate in the rotigotine group was significantly higher than in the placebo group (52% vs. 30%, P < 0.0001). Transdermal rotigotine at doses < or =8 mg/24 h did not show noninferiority to ropinirole at doses < or =24 mg/day. In a post-hoc subgroup analysis, rotigotine < or =8 mg/24 hours had a similar efficacy to ropinirole at doses < or =12 mg/day. The rotigotine transdermal patch was well tolerated. The most common adverse events were application-site reactions, nausea, and somnolence. Application-site reactions were predominantly mild or moderate in intensity. In conclusion, the rotigotine transdermal patch represents an effective and safe option for the treatment of patients with early Parkinson's disease. 相似文献
995.
Jie-Yuan Li Alberto J Espay Carolyn A Gunraj Pramod K Pal Danny I Cunic Anthony E Lang Robert Chen 《Movement disorders》2007,22(6):813-821
Mirror movements (MM) occur in early, asymmetric Parkinson's disease (PD). To examine the pathophysiology of MM in PD, we studied 13 PD patients with MM (PD-MM), 7 PD patients without MM (PD-NM), and 14 normal subjects. Cross-correlogram did not detect common synaptic input to motoneuron pools innervating homologous hand muscles in PD-MM patients. Transcranial magnetic stimulation studies showed no significant difference in ipsilateral motor-evoked potentials between PD-MM patients and normal subjects. The MM side of PD-MM patients showed a slower increase in ipsilateral silent period area with higher level of muscle contraction than the non-MM side and normal subjects. There was less interhemispheric inhibition (IHI) at long interstimulus intervals of 20 to 50 ms in PD-MM than PD-NM. IHI reduced short interval intracortical inhibition in normal subjects and PD-NM, but not in PD-MM. IHI significantly increased intracortical facilitation in PD-MM and PD-NM patients, but not in normal subjects. Our results suggest that MM in PD is due to activation of the contralateral motor cortex. PD-MM patients had reduced transcallosal inhibitory effects on cortical output neurons and on intracortical inhibitory circuits compared to PD-NM patients and controls. These deficits in transcallosal inhibition may contribute to MM in PD patients. 相似文献
996.
Christopher G Goetz Stanley Fahn Pablo Martinez-Martin Werner Poewe Cristina Sampaio Glenn T Stebbins Matthew B Stern Barbara C Tilley Richard Dodel Bruno Dubois Robert Holloway Joseph Jankovic Jaime Kulisevsky Anthony E Lang Andrew Lees Sue Leurgans Peter A LeWitt David Nyenhuis C Warren Olanow Olivier Rascol Anette Schrag Jeanne A Teresi Jacobus J Van Hilten Nancy LaPelle 《Movement disorders》2007,22(1):41-47
This article presents the revision process, major innovations, and clinimetric testing program for the Movement Disorder Society (MDS)-sponsored revision of the Unified Parkinson's Disease Rating Scale (UPDRS), known as the MDS-UPDRS. The UPDRS is the most widely used scale for the clinical study of Parkinson's disease (PD). The MDS previously organized a critique of the UPDRS, which cited many strengths, but recommended revision of the scale to accommodate new advances and to resolve problematic areas. An MDS-UPDRS committee prepared the revision using the recommendations of the published critique of the scale. Subcommittees developed new material that was reviewed by the entire committee. A 1-day face-to-face committee meeting was organized to resolve areas of debate and to arrive at a working draft ready for clinimetric testing. The MDS-UPDRS retains the UPDRS structure of four parts with a total summed score, but the parts have been modified to provide a section that integrates nonmotor elements of PD: I, Nonmotor Experiences of Daily Living; II, Motor Experiences of Daily Living; III, Motor Examination; and IV, Motor Complications. All items have five response options with uniform anchors of 0 = normal, 1 = slight, 2 = mild, 3 = moderate, and 4 = severe. Several questions in Part I and all of Part II are written as a patient/caregiver questionnaire, so that the total rater time should remain approximately 30 minutes. Detailed instructions for testing and data acquisition accompany the MDS-UPDRS in order to increase uniform usage. Multiple language editions are planned. A three-part clinimetric program will provide testing of reliability, validity, and responsiveness to interventions. Although the MDS-UPDRS will not be published until it has successfully passed clinimetric testing, explanation of the process, key changes, and clinimetric programs allow clinicians and researchers to understand and participate in the revision process. 相似文献
997.
Huntington's disease (HD) is a neurodegenerative disorder associated with expansion of CAG trinucleotide repeats in the huntingtin gene. A minimum of 36 CAG repeats is usually reported in patients with clinical features of HD; 30 to 35 repeats represent an intermediate range. Here we report a 65-year-old male with autopsy-proven HD and 29 CAG repeats. 相似文献
998.
Lorraine N Clark Eneli Haamer Helen Mejia-Santana Juliette Harris Suzanne Lesage Alexandra Durr Sabine Janin Bs Katja Hedrich Elan D Louis Lucien J Cote Howard Andrews Stanley Fahn Cheryl Waters Blair Ford Steven Frucht William Scott Christine Klein Alexis Brice Hanno Roomere Ruth Ottman Karen Marder 《Movement disorders》2007,22(7):932-937
Parkin mutations account for the majority of familial and sporadic early onset Parkinson's disease (EOPD) cases with a known genetic association. More than 100 mutations have been described in the Parkin gene that includes homozygous, compound heterozygous, and single heterozygous mutations. We have designed a Parkin mutation genotyping array (gene chip) that includes published Parkin sequence variants and allows their simultaneous detection. The chip was validated by screening 85 PD cases and 47 controls previously tested for Parkin mutations. Similar genotyping microarrays have been developed for other genetically heterogeneous diseases including age-related macular degeneration. Here, we show the utility of a genotyping array for Parkinson's disease by analysis of 60 subjects from the Genetic Epidemiology of Parkinson Disease (GEPD) study that includes 15 early-onset PD case probands and 45 relatives. 相似文献
999.
Elliot L Dimberg Sheila E Crowe Joel M Trugman Russell H Swerdlow M Beatriz Lopes T David Bourne Ted M Burns 《Movement disorders》2007,22(3):407-411
We report the case of a woman with refractory celiac disease who developed abnormal spontaneous movements of the extremities and face consistent with myorhythmia. Investigation led to a diagnosis of encephalitis, confirmed by postmortem examination. The movements were likely caused by nonparaneoplastic encephalitis associated with refractory celiac disease. Etiologic and diagnostic considerations and treatment options are discussed. 相似文献
1000.
目的通过分析颈动脉粥样硬化与冠心病的关系探讨颈动脉超声对诊断冠心病的临床意义。方法将120例入选对象分为对照组,稳定性心绞痛(SA)组,不稳定性心绞痛(UA)组,急性心肌梗死(AMI)组,每组30例,分别给予超声检测颈动脉内-中膜厚度(IMT),同时测定3组冠脉造影结果:正常组21例,单支病变组18例,多支病变组29例。结果冠心病患者IMT较正常对照组有显著增厚(P<0.01),且冠脉造影正常组与单支、多支病变组间亦存在显著性差异(P<0.05)。结论颈动脉超声检测对冠心病的预测具有确切的临床意义。 相似文献