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91.
92.
Nurses' perceived barriers to the implementation of a Fall Prevention Clinical Practice Guideline in Singapore hospitals 总被引:1,自引:0,他引:1
Serena SL Koh Elizabeth Manias Alison M Hutchinson Susan Donath Linda Johnston 《BMC health services research》2008,8(1):105
Background
Theories of behavior change indicate that an analysis of barriers to change is helpful when trying to influence professional practice. The aim of this study was to assess the perceived barriers to practice change by eliciting nurses' opinions with regard to barriers to, and facilitators of, implementation of a Fall Prevention clinical practice guideline in five acute care hospitals in Singapore. 相似文献93.
Wu DC; Liu JM; Chen YM; Yang S; Liu SM; Chen LT; Whang-Peng J 《Japanese journal of clinical oncology》1997,27(2):115-118
Hemolytic uremic syndrome spontaneously arises in a few patients with
advanced cancer, but it is more commonly related to the use of certain
chemotherapeutic agents. Mitomycin-C is, etiologically, the most common
causative agent inducing hemolytic uremic syndrome, in a dose dependent
manner. We report this syndrome, attributable to mitomycin-C at a
cumulative dose of 40 mg/m2, in a gastric cancer patient. A 42-year-old
female with stage III gastric cancer underwent radical gastrectomy and was
given mitomycin-C at 10 mg/m2 intravenously every four weeks as adjuvant
therapy. Hemolytic uremic syndrome was diagnosed three months after the
last dose of mitomycin-C administration. The most prominent symptoms
included pallor, hypertension and anasarca, with laboratory evidence of
microangiopathic hemolytic anemia, azotemia and hyperkalemia. Her disease
was progressive, but fortunately stabilized after staphylococcus column A
dialysis. Her disease remained in remission for 24 months from the time of
diagnosis, and then relapsed in the form of peritoneal carcinomatosis with
partial intestinal obstruction.
相似文献
94.
The benefits of achieving a long term event free survival of 60-70% by using increasingly intense treatment regimens must be weighed against the increased risk of treatment toxicity. From 1985 to 1990, 1612 children with childhood acute lymphoblastic leukaemia (ALL) in the UK were treated on MRC UKALL X with intensive induction therapy, central nervous system directed therapy (cranial irradiation and intrathecal methotrexate), and continuing treatment for two years. There was a randomisation to receive blocks of additional intensification treatment at five weeks, 20 weeks, not at all, or both. The five year disease free survival was 71% for children randomised to two blocks of intensification, a 14% improvement on children randomised to no intensification treatment. Treatment related mortality in this national multicentre study has been analysed for induction and first remission (including those after intensification treatment). There were 38 induction deaths, 2.3% and 53 deaths in first remission, 3.3% (including those from a second malignancy). Thirty one (84%) of the induction deaths followed an infection: bacterial in 22 and fungal in nine. Thirty seven infective remission deaths occurred: bacterial in 11, viral in 16, fungal in seven, and three caused by Pneumocystis carinii pneumonia. Ten of these deaths followed a block of intensification treatment. The majority of noninfective remission deaths followed the development of a second tumour. Risk analysis for an induction death showed girls and children with Down's syndrome to be at greater risk. For deaths in first remission analysis showed an increased risk for bone marrow transplant (BMT) patients and children with Down's syndrome. There was no effect of age and leucocyte count for either group. Most significantly when BMT patients were excluded from the analysis, intensification treatment did not increase the risk of remission death. 相似文献
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96.
Chronic sialectatic parotitis (CSP) causes problems in differential diagnosis and therapy. CSP shows the typical clinical features of chronic recurrent parotitis and will be investigated histopathologically only after ultimative parotidectomy. The etiology and pathogenesis of these unspecific inflammations is still unknown. Therefore no causal therapy is available and a lot of different trials (sialogoga, gland massage, infrared light, antibiotics, antiphlogistics, Trasylol, duct occlusion, duct ligation, gland denervation, radiotherapy) are not successful in the long run. MATERIAL AND METHOD: The salivary gland registry of the University of Hamburg (1965-1996) contains 22 infants and juvenile patients showing very severe courses of CSP. These cases have been investigated clinical (ultrasound, sialography), histopathological (paraffin embedded sections, histomorphometry of the ectatic duct lumina) and immunohistochemical (CK-MNF, AKTIN, KiM4) in a retrospective study to research the pathogenesis of CSP. RESULTS: Recurrent and always very dolent parotid swelling occurs between the age of 3 and 14 years for the first time. The courses vary from 3 months until 25 years. Local findings as well as ultrasound and sialographic features allow no certain differentiation of chronic recurrent parotitis. Conservative therapy fails in each case and leads to the necessity of surgical treatment. Histopathological three different stages of development can be observed: Initial stages show regular lobular architectonic structure of the parotid gland parenchyme with duct ectasies surrounded by slight inflammation of lymphocytes and plasmacells. Advanced stages are characterized by an increase of periductal inflammation and the appearance of lymphfollicels. Nearly complete lymphatic transformation of the parenchyme with destruction of the lobular formation dominates the terminal "immunologic" stage. Some cases show multiple myoepithelial islands within this lymphatic stroma typically observed in benign lymphoepithelial lesions. Whether bacteria nor primary obstructive changes can be observed. The histomorphometric analyses of the average and maximal luminal duct diameters show marked increase of 39% respectively 46% from and- vanced to terminal stages of CSP. Therefore the pathognomonic duct ectasies seem to depend on the progredient inflammation and are not due to a hereditary malformation of the duct system. Immunohistochemical terminal stages show follicular lymphatic hyperplasia (KiM4) expressing overshooting humoral immune reaction of MALT. CONCLUSION: Concerning the pathogenesis CSP corresponds to a immunopathological disorder of MALT and seems to be a prestage of benign lymphoepithelial lesion. Consequently important changes in the diagnosis and therapy of CSP lead to early histopathological investigation to differentiate the stage of inflammation. In stage III conservative parotidectomy should be carried out because spontaneous healing can not be expected. In contrast initial cases should be treated at first by glucocorticoids and immunosuppressives. 相似文献
97.
Lynne J Hocking Gavin J A Lucas Anna Daroszewska Tim Cundy Geoff C Nicholson Judit Donath John P Walsh Catriona Finlayson James R Cavey Barbara Ciani Paul W Sheppard Mark S Searle Robert Layfield Stuart H Ralston 《Journal of bone and mineral research》2004,19(7):1122-1127
Three novel missense mutations of SQSTM1 were identified in familial PDB, all affecting the UBA domain. Functional and structural analysis showed that disease severity was related to the type of mutation but was unrelated to the polyubiquitin-binding properties of the mutant UBA domain peptides. INTRODUCTION: Mutations affecting the ubiquitin-associated (UBA) domain of Sequestosome 1 (SQSTM1) gene have recently been identified as a common cause of familial Paget's disease of bone (PDB), but the mechanisms responsible are unclear. We identified three novel SQSTM1 mutations in PDB, conducted functional and structural analyses of all PDB-causing mutations, and studied the relationship between genotype and phenotype. MATERIALS AND METHODS: Mutation screening of the SQSTM1 gene was conducted in 70 kindreds with familial PDB. We characterized the effect of the mutations on structure of the UBA domain by protein NMR, studied the effects of the mutant UBA domains on ubiquitin binding, and looked at genotype-phenotype correlations. RESULTS AND CONCLUSIONS: Three novel missense mutations affecting the SQSTM1 UBA domain were identified, including a missense mutation at codon 411 (G411S), a missense mutation at codon 404 (M404V), and a missense mutation at codon 425 (G425R). We also identified a deletion leading to a premature stop codon at 394 (L394X). None of the mutations were found in controls. Structural analysis showed that M404V and G425R involved residues on the hydrophobic surface patch implicated in ubiquitin binding, and consistent with this, the G425R and M404V mutants abolished the ability of mutant UBA domains to bind polyubiquitin chains. In contrast, the G411S and P392L mutants bound polyubiquitin chains normally. Genotype-phenotype analysis showed that patients with truncating mutations had more extensive PDB than those with missense mutations (bones involved = 6.05 +/- 2.71 versus 3.45 +/- 2.46; p < 0.0001). This work confirms the importance of UBA domain mutations of SQSTM1 as a cause of PDB but shows that there is no correlation between the ubiquitin-binding properties of the different mutant UBA domains and disease occurrence or extent. This indicates that the mechanism of action most probably involves an interaction between SQSTM1 and a hitherto unidentified protein that modulates bone turnover. 相似文献
98.
SM Dyer IS de la Lande DB Frewin & RJ Head 《Clinical and experimental pharmacology & physiology》1998,25(3-4):246-251
1. 5-Hydroxytryptamine (5-HT) exerts both contractile and relaxant effects in the marmoset isolated aorta, actions that are unaffected by the 5-HT2 antagonist ketanserin. The aim of the present study was to define the receptors mediating the contractile activity of 5-HT in the marmoset aorta.
2. Contractile responses were elicited in aortic rings that were either: (i) precontracted submaximally with the thromboxane A2 agonist U44069 in order to amplify the responses; or (ii) exposed to N ω -nitro- L -arginine (100 μmol/L) plus LY 53857 (0.1 μmol/L; a 5-HT2 receptor antagonist shown previously to inhibit relaxation). The effect of 5-HT on adenosine 3',5'-cyclic monophosphate (cAMP) formation was also investigated.
3. The effects of agonists and antagonists comprised: (i) agonist potencies in the order 5-carboxamidotryptamine > 5-HT > sumatriptan > 8-hydroxy-2-(di- n -propylamino)tetralin; (ii) inhibition of contractile action of 5-HT by the 5-HT1D antagonist GR 127935; (iii) a contractile response to methysergide; (iv) a lack of effect of tropisetron, an antagonist of 5-HT3 and 5-HT4 receptors; and (v) inhibition of forskolin-stimulated cAMP formation by 5-HT (in the presence of LY 53857), indicative of negative coupling to adenylate cyclase.
4. The above effects fulfil the criteria for a 5-HT1 -like receptor. In view of the previous finding that this contractile response is insensitive to ketanserin, it is concluded that the contractile effects of 5-HT in the marmoset aorta are mediated exclusively by a 5-HT1 -like receptor. 相似文献
2. Contractile responses were elicited in aortic rings that were either: (i) precontracted submaximally with the thromboxane A
3. The effects of agonists and antagonists comprised: (i) agonist potencies in the order 5-carboxamidotryptamine > 5-HT > sumatriptan > 8-hydroxy-2-(di- n -propylamino)tetralin; (ii) inhibition of contractile action of 5-HT by the 5-HT
4. The above effects fulfil the criteria for a 5-HT
99.
100.