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61.
62.
Rohon-Beard cells are large, mechanosensory neurons located in the dorsal spinal cord of anamniote vertebrates. In most species studied to date, these cells die during development. We followed labeled Rohon-Beard cells in living zebrafish embryos and found that they degenerate slowly, over many days. During degeneration, the soma shrinks and finally disappears, and the processes become beady in appearance and finally break apart, but they do not retract. Zebrafish Rohon-Beard cells apparently fragment their DNA, as revealed by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) labeling, before undergoing degenerative morphologic changes. We also followed the development of labeled dorsal root ganglion neurons, as they are developing at the same stages that Rohon-Beard cells are degenerating. We found that, although axons of both cell types extend into similar regions, Rohon-Beard cells degenerate normally in mutants lacking dorsal root ganglia, providing evidence that interactions between the two cell types are not responsible for Rohon-Beard cell degeneration. Developmental Dynamics 229:30-41,2004.  相似文献   
63.
PDB is genetically heterogeneous. Mutations of the sequestosome1 gene have been reported in sporadic and familial forms of Paget's in patients of French Canadian and British descent. Mutational analyses in different ethnic groups are needed to accurately investigate hereditary diseases. We describe two novel mutations of sequestosome1 in 62 Italian sporadic patients, confirming the role of the encoded protein in this disorder. INTRODUCTION: Paget's disease of bone (PDB) is a relatively common disease of bone metabolism reported to affect up to 3% of whites over 55 years of age. The disorder is genetically heterogeneous, and at present, there is scientific evidence that at least eight different human chromosomal loci are correlated with its pathogenesis. Mutations of the sequestosome1 (SQSTM1) gene were identified as responsible for most of the sporadic and familial forms of Paget in patients of French Canadian and British descent. Such mutations were located at exon 7 and 8 levels, encoding for the ubiquitin protein-binding domain (UBA) and representing a mutational hot spot area. MATERIALS AND METHODS: To verify the involvement of this gene in Italian subjects affected by PDB, we performed mutational analysis in 62 sporadic PDB cases. RESULTS: We described three different mutations at exon 8 level: P392L, already described in the French Canadian population and families predominantly of British descendent, and two novel mutations consisting of the amino acid substitutions M404V and G425R. No significant differences in the clinical history of PDB have been observed in patients with SQSTM1 mutations in respect to those without. CONCLUSIONS: Even though our findings suggest a minor involvement of the SQSTM1 gene in the pathogenesis of sporadic Italian Paget's cases, the identification of different significant mutations within the SQSTM1 gene in unrelated, but clinically similar individuals, offers extremely convincing evidence for a causal relationship between this gene and PDB. Longitudinal studies are needed to assess the penetrance of genotype/phenotype correlations. Our findings confirm the evidence of a clustered mutation area at this level in this disorder.  相似文献   
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Dopamine agonists have been recommended as early treatment for Parkinson's disease (PD), alone or combined with levodopa. Piribedil is a non-ergot selective D(2)/D(3) agonist with alpha(2) antagonist properties shown to be effective in the treatment of PD. This 12-month international, randomized, double-blind trial aimed to assess the efficacy of piribedil 150 mg versus bromocriptine 25 mg, in early combination with levodopa in Stage I to III PD patients. Motor efficacy was assessed using the Unified Parkinson's Disease Rating Scale (UPDRS III, Items 18-31) as improvement from baseline. Response rate was defined as a 30% improvement. Among the 425 randomly assigned patients, 178 were also included in a substudy on cognitive follow-up evaluated by a dysexecutive syndrome oriented battery. A relevant improvement in UPDRS III over the 12-month study duration was observed both in the piribedil and bromocriptine groups (-7.9 +/- 9.7 points from baseline versus -8.0 +/- 9.5; not significant [n.s.]) with a response rate of 58.4% and 55.3% (n.s.), respectively. Piribedil and bromocriptine resulted in similar improvement on all UPDRS III subscores. Piribedil patients required less levodopa dose increase than those on bromocriptine. Cognitive performance remained generally unchanged in both groups, with a significant effect of piribedil limited to the Wisconsin Card Sorting Test. An overall good tolerability of piribedil was observed. Early combination of piribedil 150 mg with levodopa resulted in significant long-term improvement of all motor symptoms in PD patients insufficiently controlled by levodopa alone. Taking into account both efficacy and acceptability in the long-term, piribedil proved in this bromocriptine controlled study to be an effective and safe treatment for PD.  相似文献   
66.
We reviewed clinical, EEG, and CT findings of 203 patients with epilepsy due to neurocysticercosis. Seizures were generalized in 121 patients and partial in 82. Thirty-two patients had focal signs and eight had papilledema. Eighty-one had generalized and 16 had focal EEG abnormalities. CT showed parenchymal brain calcifications in 53 patients and cysts in 150. There was an increased rate of focal signs in patients with single cysts as compared with patients with multiple cysts, and focal EEG abnormalities were present only in patients with single cysts. Fifty patients were lost to follow-up. The remaining 153 patients were followed for 28 +/- 6 months; of these, 31 had calcifications and 122 had cysts. Anticonvulsants were started after the first visit in every patient. The 31 patients with calcifications remained free of seizures. Ninety-five of the 122 patients with cysts were also treated with anticysticercal drugs; of these, 79 (83%) had control of seizures. In contrast, only seven (26%) of 27 patients who did not receive anticysticercal drugs had control of seizures, indicating a strong correlation between the use of anticysticercal drugs and seizure control. Finally, of the 21 patients in whom anticonvulsants were withdrawn, 16 had relapses.  相似文献   
67.
Management and survival of meconium ileus. A 30-year review.   总被引:2,自引:0,他引:2       下载免费PDF全文
Cystic fibrosis patients born with meconium ileus (MI) have had an improved outcome over the last three decades. The authors reviewed the impact of surgical management and long-term nutritional care on the survival of patients with MI. Of the 59 cases of MI seen from 1959 to 1989, 48 cases were managed operatively using either the Bishop-Koop ileostomy (BK), the Mikulicz ileostomy, primary resection and anastomosis (RA), or ileostomy. Six-month survival of MI has improved from 37% to 100%. Nonoperative cases (n = 11) had 100% long-term survival. The RA survivors required less late operative intervention (20%) as compared with other surgical patients (81%). A comparison of serial growth percentiles of CF patients with MI with those of their non-MI CF peers showed similar long-term decreases. These data confirm: (1) There is an improved survival for MI independent of the surgical procedure; (2) The BK ileostomy is an effective and time-tested MI treatment; (3) Primary resection and anastomosis in selected cases may have a lower surgical morbidity rate; and (4) Meconium ileus does not adversely affect the long-term nutritional outcome of CF patients.  相似文献   
68.
Albendazole is considered to be the drug of choice for treatment of parenchymal brain cysticercosis. Its efficacy, however, for treatment of subarachnoid cysticerci has not been established, to our knowledge. In this study, we treated four patients who had giant subarachnoid cysticerci with albendazole at daily doses of 15 mg/kg of body weight for 8 days. Computed tomographic studies showed that all cysts disappeared 3 months after the end of treatment. This was associated with marked clinical improvement in every case. Our results indicated that albendazole is highly effective for treatment of this form of the disease.  相似文献   
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70.
OBJECTIVE: A relationship between brain atrophy and delta rhythmicity (1.5-4 Hz) has been previously explored in Alzheimer's disease (AD) subjects [Fernandez A, Arrazola J, Maestu F, Amo C, Gil-Gregorio P, Wienbruch C, Ortiz T. Correlations of hippocampal atrophy and focal low-frequency magnetic activity in Alzheimer disease: volumetric MR imaging-magnetoencephalographic study. Am J Neuroradiol. 2003 24(3):481-487]. In this study, we tested the hypothesis that such a relationship does exist not only in AD patients but also across the continuum of subjects with mild cognitive impairment (MCI) and AD. METHODS: Resting, eyes-closed EEG data were recorded in 34 MCI and 65 AD subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by LORETA. Cortical EEG sources were correlated with MR-based measurements of lobar brain volume (white and gray matter). RESULTS: A negative correlation was observed between the frontal white matter and the amplitude of frontal delta sources (2-4 Hz) across MCI and AD subjects. CONCLUSIONS: These results confirmed for the first time the hypothesis that the sources of resting delta rhythms (2-4 Hz) are correlated with lobar brain volume across MCI and AD subjects. SIGNIFICANCE: The present findings support, at least at group level, the 'transition hypothesis' of brain structural and functional continuity between MCI and AD.  相似文献   
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