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21.
Expansion of CAG trinucleotide repeats that encode polyglutamine is the underlying cause of at least nine inherited human neurodegenerative disorders, including Huntington's disease and spinocerebellar ataxias. PolyQ fragments accumulate as aggregates in the cytoplasm and/or in the nucleus, and induce neuronal cell death. However, the molecular mechanism of polyQ-induced cell death is controversial. Here, we show the following: (1) polyQ with pathogenic repeat length triggers ER stress through proteasomal dysfunction; (2) ER stress activates ASK 1 through formation of an IRE1-TRAF2-ASK1 complex; and (3) ASK1(-/-) primary neurons are defective in polyQ-, proteasome inhibitor-, and ER stress-induced JNK activation and cell death. These findings suggest that ASK1 is a key element in ER stress-induced cell death that plays an important role in the neuropathological alterations in polyQ diseases.  相似文献   
22.
The stereoregularity of poly(methyl vinyl ketone) (PMVK) was determined by NMR spectra of the polymers. Isotactic and atactic PMVK's were thermally degraded, and thermogravimetric analysis, IR and visible and UV spectroscopy were applied to elucidate the mechanism of the degradation. It was found that the isotactic polymer begins to degrade at lower temperature than the atactic polymer, but its rate becomes lower than that of the atactic polymer at temperatures higher than 320°C. If the two types of polymers were treated at a constant temperature (200°C) for varying times under N2 atmosphere, the isotactic polymer showed a higher degradation rate as determined by thermogravimetric analysis and IR spectroscopy. The isotactic polymer shows a higher tendency to form a monocyclic structure in the heat treatment than the atactic polymer. This is similar to poly(isopropenyl methyl ketone).  相似文献   
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24.
The present study was designed to examine the usefulness of 2,3-dimercaptosuccinic acid (DMSA) for the purpose of reducing cis-diamminedichloroplatinum (DDP)-induced nephrotoxicity and effective clinical use of DDP and safe. The effectiveness of DMSA on the DDP-excretion in rat kidney was observed by measuring the platinum concentration using Atomic Absorption Instrument. Co-administration of DMSA (1.0 or 2.0 mmol/kg) 1 hour after DDP injection (20 mumol/kg) showed more decrease in the platinum concentration than that immediately after DDP injection. The alleviating effect of DMSA on DDP toxicity was evaluated by lipid peroxidation, enzymatic antioxidants, and glutathione levels. The administration of DDP alone caused a significant increase in lipid peroxidation and significant decreases in enzymatic antioxidants and glutathione levels in the kidney. Co-administration of DMSA (2.0 mmol/kg) 1 hour after DDP injection showed the most effective reduction of these enzymatic damages caused by DDP. These findings suggested that the co-administration of DMSA (2.0 mmol/kg) 1 hour after DDP injection leads DDP to effective excrete from renal tissue and suppresses the lipid peroxide reaction and results in reduction of nephrotoxicity.  相似文献   
25.
BACKGROUND: Symptoms of ischemic attacks in the internal carotid system usually involve focal cerebral dysfunction, i.e., hemiparesis or aphasia. However, an ischemic attack in the vertebrobasilar artery system usually presents with combined symptoms. The variety of manifestations included in the vertebrobasilar profile makes the potential pattern of symptoms considerably more variable and complex than that in the carotid system. Manifestations can include syncope and also vertigo. METHOD AND RESULTS: A 42-year-old woman experienced frequent attacks of faintness with vertigo. Angiography demonstrated severe stenosis of the left internal carotid artery with a persistent primitive hypoglossal artery just distal to the stenosis. The right internal carotid artery was normal and cross circulation through the anterior communicating artery was not well developed. Both vertebral arteries were hypoplastic. The patient underwent carotid endarterectomy and, thereafter the episodes of syncope completely disappeared. CONCLUSION: It was supposed that global ischemia including the brain stem occurred because of stenosis of the left internal carotid artery attributable to the presence of a primitive hypoglossal artery.  相似文献   
26.
OBJECTIVE: The aim of this study was to clarify the relationship between morphologic changes of the pituitary gland and the genotype of Prophet of Pit-1 (PROP1), a newly discovered gene responsible for congenital combined pituitary hormone deficiency, in a series of eight humans with this disorder. CONCLUSION: Congenital hypoplasia of the anterior pituitary gland is the most common MR imaging finding in patients with combined pituitary hormone deficiency. Our findings suggest a crucial role for PROP1 in pituitary organogenesis as well as anterior pituitary cell differentiation.  相似文献   
27.
Atypical Shone''s complex is a rare congenital anomaly involving a left-sided obstructive lesion of two or three cardiovascular levels. A 70-year-old man with dyspnea on exertion was diagnosed with severe aortic stenosis (AS) with a bicuspid valve, complicated by severe aortic coarctation (CoA) and a double-orifice mitral valve. He underwent surgery for AS and CoA in one session. It is important to search for complicated malformations, even in cases of bicuspid aortic valve found in old age.  相似文献   
28.
Aims/IntroductionGlucagon‐like peptide‐1 receptor agonists (GLP‐1 RA) might be less effective in patients with severe hyperglycemia, because hyperglycemia downregulated the GLP‐1 receptor in an animal study. To examine this hypothesis clinically, we compared the glucose‐lowering effects of GLP‐1 receptor agonist liraglutide with and without prior glycemic control.Materials and MethodsIn an open‐label, parallel trial, participants with poorly controlled type 2 diabetes were recruited and randomized to receive once‐daily insulin therapy, degludec (Insulin–GLP‐1 RA relay group, mean 16.8 ± 11.4 IU/day), for 12 weeks and then liraglutide for 12 weeks or subcutaneous injections of GLP‐1 RA, liraglutide (GLP‐1 RA first group, 0.9 mg), for 24 weeks. The primary efficacy end‐points consisted of changes in the levels of fasting plasma glucose and glycated hemoglobin (HbA1c).ResultsThe median fasting plasma glucose and HbA1c before the study were 210.0 mg/dL and 9.8%, respectively. The levels of fasting plasma glucose and HbA1c significantly decreased in the Insulin–GLP‐1 RA relay group (P < 0.001) and GLP‐1 RA first group (P < 0.001) by week 24, although no intergroup differences were observed. The reduction of HbA1c in the Insulin–GLP‐1 RA relay group tended to be larger than that in the GLP‐1 RA first group in the lowest CPR (C‐peptide immunoreactivity) quartile (P = 0.072). The adverse events consisted of gastrointestinal problems, followed by hypoglycemia.ConclusionsThe GLP‐1 receptor agonist is overall effective without prior glycemic control with insulin in participants with poorly controlled type 2 diabetes. However, in participants with insulinopenic type 2 diabetes, prior glycemic control with insulin might overcome glucose toxicity‐induced GLP‐1 resistance.  相似文献   
29.
Although neoantigens are one of the most favorable targets in cancer immunotherapy, it is less versatile and costly to apply neoantigen‐derived cancer vaccines to patients due to individual variation. It is, therefore, important to find highly immunogenic antigens between tumor‐specific or associated antigens that are shared among patients. Considering the cancer immunoediting theory, immunogenic tumor cells cannot survive in the early phase of tumor progression including two processes: elimination and equilibrium. We hypothesized that highly immunogenic molecules are allowed to be expressed in tumor cells after an immune suppressive tumor microenvironment was established, if these molecules contribute to tumor survival. In the current study, we focused on TWIST1 as a candidate for highly immunogenic antigens because it is upregulated in tumor cells under hypoxia and promotes tumor metastasis, which is observed in the late phase of tumor progression. We demonstrated that TWIST1 had an immunogenic peptide sequence TWIST1140–162, which effectively activated TWIST1‐specific CD4+ T‐cells. In a short‐term culture system, we detected more TWIST1‐specific responses in breast cancer patients compared with in healthy donors. Vaccination with the TWIST1 peptide also showed efficient expansion of TWIST1‐reactive HTLs in humanized mice. These findings indicate that TWIST1 is a highly immunogenic shared antigen and a favorable target for cancer immunotherapy.  相似文献   
30.
A man in his 30s injected insulin several times into his abdomen and was found dead several hours later. Micropathological findings showed alveolar injury with hemorrhaging and cerebral parietal lobe nerve cell edema. Biochemical examinations showed that the blood insulin level was high, significantly so at the insulin injection sites. The blood glucose and C-peptide levels were low. The insulin level in the kidneys was low. In forensic medicine, a postmortem diagnosis of insulin subcutaneous injection is often difficult. When insulin injection is suspected, particularly high insulin levels can be expected at the insulin injection site, rather than in the blood.  相似文献   
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