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991.
The surgical treatment of Parkinson’s disease has been through a revival phase over the last 20 years with the development
of deep brain stimulation (DBS). Thalamic DBS was developed first and has proven to be a very effective treatment for tremor.
The limitation is the lack of effect on other symptoms. Other targets were therefore investigated, and the procedure was applied
to the subthalamic nucleus (STN) and the internal globus pallidus (GPi). STN stimulation can improve a wide range of symptoms
and is currently the preferred target for many patients. Nevertheless, the morbidity seems higher than with other targets,
and the selection criteria have to be quite strict. When STN DBS is not advised, thalamic DBS remains an option for patients
with severe tremor, and GPi stimulation for those with severe dyskinesias. DBS remains a symptomatic treatment for a limited
number of patients; it does not seem to alter the disease progression, and many patients are not suitable. There is, therefore,
the need for further research into other targets and other approaches. 相似文献
992.
993.
Albert F.G. Leentjens MD PhD Kathy Dujardin PhD Laura Marsh MD Pablo Martinez‐Martin MD PhD Irene H. Richard MD Sergio E. Starkstein MD Daniel Weintraub MD Cristina Sampaio MD Werner Poewe MD Oliver Rascol MD Glenn T. Stebbins PhD Christopher G. Goetz MD 《Movement disorders》2008,23(14):2004-2014
Apathy is a common condition in Parkinson's disease (PD) and is generally defined as a lack of motivation. It is associated with more severe cognitive dysfunction and a decrease in activities of daily living (ADL) performance. Anhedonia, the inability to experience pleasure, can be a symptom of both depressive and apathetic syndromes. The Movement Disorder Society (MDS) commissioned a task force to assess the clinimetric properties of apathy and anhedonia scales in PD patients. A systematic literature review was conducted to identify scales that have either been validated or used in PD patients. Apathy scales identified for review include the Apathy Evaluation Scale (AES), the Apathy Scale (AS), the Apathy Inventory (AI), and the Lille Apathy Rating Scale (LARS). In addition, item 4 (motivation/initiative) of the Unified Parkinson's Disease Rating Scale (UPDRS) and item 7 (apathy) of the Neuropsychiatric Inventory (NPI) were included. Anhedonia scales identified for review were the Snaith‐Hamilton Pleasure Scale (SHAPS) and the Chapman scales for physical and social anhedonia. Only the AS is classified as “recommended” to assess apathy in PD. Although item 4 of the UPDRS also meets the criteria to be classified as recommended, it should be considered for screening only because of the obvious limitations of a single item construct. For the assessment of anhedonia, only the SHAPS meets the criteria of “Suggested.” Information on the validity of apathy and anhedonia scales is limited because of the lack of consensus on diagnostic criteria for these conditions. © 2008 Movement Disorder Society 相似文献
994.
995.
Aldo Balsamo Marco Benvenuti Irene Giorgi Bruno Macchia Franco Macchia Susanna Nencetti Elisabetta Orlandini Armando Rossello Giampietro Broccali 《European journal of medicinal chemistry》1989,24(6)
The cepham (9) and the penam (10) derivatives, with their carboxylic group in the “wrong” β-configuration, which is opposite to that exhibited by the common penicillins, were synthesized and assayed in vitro for antimicrobial properties. Compounds 9 and 10, tested on Gram-positive and Gram-negative bacteria, both sensitive and resistant to β-lactamase inactivation, exhibited a very poor activity, directed only against non-β-lactamase-producing Gram-positive bacteria. One of the possible explanations for these results may be found in unfavourable steric and electronic effects deriving from the α-oriented methoxy group which is adjacent to the pharmacophoric carboxylic function. 相似文献
996.
Irene Tesseraux Michael Gülden Otmar Wassermann 《Naunyn-Schmiedeberg's archives of pharmacology》1987,336(2):232-239
Summary Mononucleated myogenic cells (satellite cells) were isolated from skeletal muscle of adult rats and grown in culture. These cells replicated and, beginning with the 6th day in culture, they fused and differentiated into multinucleated myotubes, which accumulated creatine kinase and developed cross striation and spontaneous contractions. The differentiation of the excitable membrane and the action of sea anemone toxin ATX II were investigated with microelectrode techniques. Mature myotubes reached a stable membrane potential of –47.3 mV (±6.5 mV) with the IIth day in culture. Action potentials could be generated in all myotubes. During maturation they became faster (increasing rate of rise) and shorter in duration. In spontaneously contracting myotubes spontaneous action potentials were recorded, which were often associated with subthreshold oscillations of membrane potential. ATX II reduced the membrane potential and prolonged the action potential duration with the lowest effective concentrations being 1 nmol/l and 0.5 nmol/l, respectively. Furthermore, ATX II induced electrical activity in quiescent myotubes. After fusion the development of the membrane electrical properties of satellite cell derived muscle cells followed essentially the same pattern as in primary cultures of embryonic myotubes. Electrophysiologically and with respect to their sensitivity to ATX II the mature myotubes resemble denervated muscle fibres.
Send offprint requests to I. Tesseraux at the above address 相似文献
997.
998.
Pratima K Singh David H Gutmann Christine E Fuller Irene F Newsham Arie Perry 《Modern pathology》2002,15(5):526-531
Ependymomas are malignant CNS neoplasms with highly variable biologic behavior, including a generally better prognosis for intraspinal tumors. Inactivation of the NF2 gene on 22q12 and loss of its protein product, merlin, have been well documented in subsets of meningiomas and ependymomas. DAL-1, a related tumor suppressor and protein 4.1 family member on 18p11.3, has also been recently implicated in meningioma pathogenesis, though its role in ependymoma remains unknown. Therefore, we evaluated 27 ependymomas (12 intracranial and 15 spinal) using fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) to determine NF2/merlin and DAL-1/DAL-1 status at the DNA and protein levels. Demonstrable NF2 and DAL-1 gene deletions were each detected in 6 (22%) ependymomas. All 5 merlin losses by IHC occurred in spinal ependymomas (P =.047), whereas 5 (71%) DAL-1-negative cases were intracranial (P =.185). The former result is consistent with prior observations that NF2 mutations are generally limited to spinal ependymomas. In contrast to meningiomas, simultaneous merlin and DAL-1 losses were not encountered. Our findings suggest that (1) NF2 and DAL-1 losses are involved in the pathogenesis of spinal and intracranial ependymoma subsets, respectively and (2) given the number of cases with no demonstrable losses, other cellular perturbations must also be critical for tumori-genesis. 相似文献
999.
Frans M. Kaspersen Irene H. G. Schlachter Carel W. Funke Gerard N. Wagenaars Jan-Remt Mellema 《Journal of labelled compounds & radiopharmaceuticals》1991,29(5):613-616
To increase the bio-availability of naturally occurring steroids, esterification of the 17-hydroxy position is a useful approach. Besides (branched) alkanecarboxylic acids1) and cyclohexanecarboxylic acid2) also cyclooctyl acetic acid ( 1 ) was applied. To establish the biological fate of the cyclooctyl acetic acid part of steroids the tritiated molecule was synthesized (Figure 1). Cyclooctanone ( 3 ) was condensed with cyanoacetic acid3) and the resulting cyanide ( 4 ) was hydrolyzed to cyclooctenyl acetic acid ( 2a )4) which contained according to 1H NMR and 13C NMR 20% of the isomeric 2b (1H NMR (C2HCl3): 5,58 ppm (t, CH of 2a ) and 5,63 ppm (br.s CH of 2b ) 13C NMR(C2HCl3): 129,6 ppm (CH of 2a ) and 115,0 ppm (CH of 2b )). 相似文献
1000.