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81.
The recent clinical results are reviewed of stereotactic radiosurgery/radiotherapy for the treatment of pituitary adenomas. The outcomes of pituitary adenomas treated by stereotactic radiosurgery/radiotherapy with gamma knife, CyberKnife, or linear accelerator (LINAC) radiosurgery were evaluated from articles published after 2004. Each study was evaluated for the number of patients, radiosurgical parameter (marginal dose), length of follow up, tumor growth control, rate of hormonal normalization in secretary adenomas, and adverse events. After gamma knife radiosurgery, the tumor reduction rates varied from 42.3% to 89% in non-secreting adenomas. However, the tumor control rates in non-secreting adenomas were more than 90% in most studies. In growth hormone-secreting adenomas, the rates of insulin-like growth factor-1 normalization ranged from 36.9% to 82%. In adrenocorticotropin-secreting adenomas, the rates for 24-hour urine free cortisol normalization ranged from 27.9% to 54%. In prolactin-secreting adenomas, the prolactin normalization ranged from 17.4% to 50%. New hormonal deficits ranged from 0% to 34%. New visual deficits were relatively low. The number of patients treated with CyberKnife and LINAC radiosurgery/radiotherapy was small and follow-up periods were relatively short compared to those with gamma knife treatment, but the clinical outcomes after these therapies were similar to those after gamma knife therapy. Image-guided stereotactic radiosurgery/radiotherapy with the gamma knife, CyberKnife, or LINAC system is effective and safe against pituitary adenomas. Careful long-term follow up of the patients is necessary because of long-term anti-tumor effects and delayed adverse events.  相似文献   
82.
A 59-year-old man with a long history of hypertension and diabetes was admitted to our hospital with acute type B aortic dissection 14 days after the sudden onset of back pain. The dissecting descending thoracic aorta was enlarged to 5.2 cm in diameter, and laboratory tests showed an elevated white blood cell count (15 530/mm3) and an increased C-reactive protein level (19.2 mg/dl). Computed tomography performed 2 days after admission revealed rapid growth of the aortic dissection. Blood cultures obtained upon admission were positive for Salmonella. Impending rupture of the aortic dissection complicated by Salmonella infection was strongly suspected, and the patient underwent emergency surgery consisting of debridement and prosthetic graft placement covered by an omental flap. In this case, it is believed that insidious Salmonella aortitis caused acute type B aortic dissection.  相似文献   
83.
The histologic hallmark of Parkinson disease (PD) is loss of pigmented neurons in the substantia nigra (SN) and locus ceruleus (LC) with accumulation of alpha-synuclein (alphaS). It has been reported that tyrosine hydroxylase (TH)-negative pigmented neurons are present in these nuclei of patients with PD. However, the relationship between TH immunoreactivity and alphaS accumulation remains uncertain. We immunohistochemically examined the SN and LC from patients with PD (n = 10) and control subjects (n = 7). A correlation study indicated a close relationship among decreased TH immunoreactivity, alphaS accumulation, and neuronal loss. In addition, 10% of pigmented neurons in the SN and 54.9% of those in the LC contained abnormal alphaS aggregates. Moreover, 82.3% of pigmented neurons bearing alphaS aggregates in the SN and 39.2% of those in the LC lacked TH immunoreactivity, suggesting that pigmented neurons in the SN have a greater tendency to lack TH activity than those in the LC. Recent studies have shown that this decrease of TH activity leads to a decrease of cytotoxic substances and that decreased dopamine synthesis leads to a reduction of cytotoxic alphaS oligomers. Therefore, the decrease of TH immunoreactivity in pigmented neurons demonstrated here can be considered to represent a cytoprotective mechanism in PD.  相似文献   
84.
The aim of this retrospective observational study was to delineate determinants for antegrade flow and entire patency of the sequential radial artery graft (RAG) in the left circumflex artery (LCX) and right coronary artery (RCA). Angiograms of 432 RAGs, which were sequentially anastomosed to the LCX and RCA, and were proximally anastomosed with the in-situ internal thoracic artery as the composite I- or Y-graft, were studied. The mean targets of RAG were 2.83±0.79. We examined effects of characteristics of RAG and the targets, such as native coronary stenosis and their combinations, on competitive flow and occlusion. Of 432 RAGs, 413 (95.6%) were patent to all targets, while 331 (76.6%) provided antegrade flow to all targets in sequential anastomoses. By the univariate and multivariate analyses, 51-75% stenosis of the most distal target was identified as the significant predictor of competitive flow or occlusion (OR=8.59, P<0.0001). The cumulative graft patency rate of RAGs with 76-100% stenosis of the most distal target at 40 months was 88.6%, whereas that of RAGs with 51-75% stenosis of the most distal target was 59.1% (P<0.0001). In sequential RAG, severity of stenosis in the most distal target had the significant impact on prevention of competitive flow and long-term patency to all targets.  相似文献   
85.
Primary cricopharyngeal dysfunction (PCD) is a rare idiopathic disorder of the upper esophageal sphincter (UES), characterized by oropharyngeal dysphagia, frequent aspiration, and narrowing at the level of the UES. Cricopharyngeal myotomy (CPM) has been used to treat oropharyngeal dysphagia of different causes including anatomic, neuromuscular, iatrogenic, inflammatory, neoplastic, and idiopathic; however, the indications for CPM and predictors of its outcome are not clearly defined. We report a case of PCD with hypertonic UES caused by a structural abnormality localized in the cricopharyngeus muscle, visualized as a cricopharyngeal bar, which we treated successfully by CPM, achieving long-term relief.  相似文献   
86.
87.
A 56-year-old female who had been diagnosed with Ebstein's anomaly was admitted with cyanosis and congestive heart failure. The echocardiogram showed severe tricuspid valve incompetence, displacement of the tricuspid valve and dilatation of the atrialized portion of the right ventricle. Atrial fibrillation was detected in the electrocardiogram. She underwent tricuspid valve replacement and right atrial maze procedure. She is released from congestive heart failure and remains in sinus rhythm 48 months after the operation.  相似文献   
88.
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare cardiac disorder characterized by replacement of myocytes with adipose and fibrous tissue and often presents with ventricular arrhythmia, heart failure, and sudden death. This report describes a 67-year-old man with ARVC complicated with severe mitral regurgitation, dilated annulus of the tricuspid valve, and coronary artery-pulmonary artery fistula. Mitral valve repair, tricuspid valve annuloplasty, and ligation of the coronary artery-pulmonary artery fistula were performed. The postoperative course was uneventful, and the patient was discharged on postoperative day 15.  相似文献   
89.
General anesthetic-induced unresponsiveness covers a spectrum of different behavioral components, namely, (1) amnesia, (2) sedation/hypnosis, (3) analgesia, and (4) immobility. At the molecular and cellular level, anesthetic drugs have been shown to have effects on a wide rage of putative targets, such as ligand-gated ion channels (GABA, glycine, NMDA receptors), other ion channels (K+, Na+, Ca2+), and other intracellular functions. This mini-review summarizes recent topics in this research field focusing on NMDA and GABA receptors. Although ketamine blocks NMDA receptors as an open channel blocker, it has been recently shown that ketamine inhibits hyperpolarization-activated cationic currents (J Neurosci 2009) and also enhances GABA-induced currents in alpha6 GABA receptors (J Neurosci 2008). In addition, ketamine (0.5 microM, 24h) produces loss of phenotype of fast-spiking interneurons via NADPH-oxidase (Science 2007). These data suggests that ketamine have multiple molecular targets in hypnotic, analgesic and amnestic actions. Propofol has been shown to enhance two types of GABAergic inhibition: a synaptic form (phasic inhibition) regulating neural excitability via the activation of postsynaptic GABAA receptors by intermittent GABA release from presynaptic terminals ; and a persistent tonic form (tonic inhibition) generated by continuous activation of extrasynaptic GABAA receptors by low concentrations of ambient GABA. However, the roles of tonic inhibition in hypnotic actions of isoflurane and sevoflurane are less clear. In this mini review, the relative contributions of extrasynaptic GABA receptors in behavioral actions of isoflurane and sevoflurane will be discussed.  相似文献   
90.
Adipose tissue-derived stem cells (ASCs) are expected to have clinical applications as well as other stem cells, because ASCs can be obtained safely from adult donors and used in autologous therapies without concern about rejection and the need for immunosuppression. However, the use of gene transfer with Sendai virus (SeV) vectors, which can efficiently introduce foreign genes without toxicity into several cells, with ASCs has not yet been investigated. This study documents on the use of SeV vectors for gene transfer to ASCs. The dose-dependent GFP expression of ASCs transfected with SeV vectors after 48 h of culture at 37 degrees C was first evaluated. Next, the cellular toxicity of ASCs transfected with SeV vectors was verified. In addition, SeV vectors were compared with adenovirus (AdV) vectors. Finally, the time-dependent GFP expression of ASCs transfected with SeV vectors was evaluated. The results showed that transfection of ASCs with SeV vectors results in more efficient expression of transgene (GFP expression) in the ASCs than with AdV vectors after 48 h of culture at 37 degrees C. Moreover, while the transfection of ASCs with AdV vectors at high MOIs was cytotoxic (a lot of transfected cells died) that of ASCs with SeV vectors at high MOIs was not necessarily cytotoxic. In addition, the preservation of multilineage ASCs transfected with SeV was observed. In conclusion, this is the first report describing the successful use of SeV-mediated gene transfer in ASCs, and the results indicate that SeV may thus provide advantages with respect to safety issues in gene therapy.  相似文献   
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