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81.
Brevik A Vollset SE Tell GS Refsum H Ueland PM Loeken EB Drevon CA Andersen LF 《The American journal of clinical nutrition》2005,81(2):434-439
BACKGROUND: Nutritional biomarkers may be used to assess dietary exposure without the errors commonly associated with self-reported dietary data. OBJECTIVE: The objective was to examine the association between plasma folate and intake of folate, fruit, and vegetables in a large cohort of healthy adults consuming foods that had not been fortified with folic acid. DESIGN: The present study population included 5533 middle-aged (47-49 y) and old (71-74 y) subjects from the Hordaland Homocysteine Study. The participants completed a food-frequency questionnaire and provided blood samples for chemical analyses. RESULTS: We observed a significant difference in plasma concentrations of folate across increasing quartiles of fruit, vegetable, and orange juice consumption. The difference in plasma folate between the highest and lowest quartiles was 1.97 (95% CI: 1.86, 2.07) nmol/L for fruit intake, 1.79 (95% CI: 1.69, 1.89) nmol/L for vegetable intake, and 2.69 (95% CI: 2.51, 2.87) nmol/L for orange juice intake. A significant inverse relation was observed across increasing quartiles of milk and bread intakes. The difference between the highest and lowest quartiles was -1.03 (95% CI: -1.13, -0.92) nmol/L for milk and -1.60 (95% CI: -1.69, -1.50) nmol/L for bread. CONCLUSION: Plasma folate concentration may be a useful biomarker for the intake of fruit and vegetables in populations consuming unfortified food products. The association can be attenuated by and should be corrected for individual intake of folic acid supplements. 相似文献
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83.
Background
Pregnancy-related pelvic pain is a common condition, and use of hormonal contraceptives before pregnancy has been proposed as a risk factor. We used data from a sub-sample of women participating in the "Norwegian Women and Cancer study" (NOWAC) to assess the association between hormonal contraceptive use and pelvic pain in pregnancy. 相似文献84.
Escitalopram versus citalopram: the surprising role of the <Emphasis Type="Italic">R</Emphasis>-enantiomer 总被引:10,自引:0,他引:10
Rationale Citalopram is a racemate consisting of a 1:1 mixture of the R(–)- and S(+)-enantiomers. Non-clinical studies show that the serotonin reuptake inhibitory activity of citalopram is attributable to the S-enantiomer, escitalopram. A series of recent non-clinical and clinical studies comparing escitalopram and citalopram to placebo found that equivalent doses of these two drugs, i.e. containing the same amount of the S-enantiomer, showed better effect for escitalopram. These results suggested that the R-citalopram in citalopram inhibits the effect of the S-enantiomer.Objective To review the pharmacological and non-clinical literature that describes the inhibition of escitalopram by R-citalopram, as well as the implications of this inhibition for the clinical efficacy of escitalopram compared to citalopram.Methods The information in this review was gathered from published articles and abstracts.Results In appropriate neurochemical, functional, and behavioural non-clinical experiments, escitalopram shows greater efficacy and faster onset of action than comparable doses of citalopram. The lower efficacy of citalopram in these studies is apparently due to the inhibition of the effect of the S-enantiomer by the R-enantiomer, possibly via an allosteric interaction with the serotonin transporter. Data from randomised clinical trials consistently show better efficacy with escitalopram than with citalopram, including higher rates of response and remission, and faster time to symptom relief.Conclusion The R-enantiomer present in citalopram counteracts the activity of the S-enantiomer, thereby providing a possible basis for the pharmacological and clinical differences observed between citalopram and escitalopram. 相似文献
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87.
Incorporation of an ERA attachment for obturator framework design: a clinical report 总被引:5,自引:0,他引:5
Sigurgeirsdottir E Minsely GE Rothenberger SL 《The Journal of prosthetic dentistry》2002,87(5):477-480
Swinglock framework designs have been used to retain obturators for some time. One of the problems with Swinglock designs has been loss of retention due to wear of the metal latch assembly. This clinical report describes the incorporation of an ERA attachment as the latch assembly of a Swinglock framework for an obturator. The premise behind this design was that wear would be at the expense of the nylon retention male component, which is easily interchangeable, rather than the metal component of the assembly. The life of the latch assembly, framework, and prosthesis would thereby be prolonged. 相似文献
88.
Farrell RJ Agarwal B Brandwein SL Underhill J Chuttani R Pleskow DK 《Gastrointestinal endoscopy》2002,56(5):681-687
BACKGROUND: Distinguishing malignant from benign biliary strictures remains a challenge. This prospective study assessed intraductal US as an adjunct to endoscopic retrograde cholangiography and tissue sampling for diagnosis of malignant and benign biliary strictures. METHODS: Sixty-two patients were enrolled who had biliary strictures suspected to be malignant but with negative tissue sampling by endoscopic retrograde cholangiography, or suspected biliary strictures based on clinical manifestations and/or cross-sectional imaging. Intraductal US was performed with an over-the-wire 2.4-mm diameter 20 MHz catheter US probe. The diagnostic accuracy of endoscopic retrograde cholangiography plus tissue sampling with and without intraductal US was compared with surgical findings or clinical outcome at a 12-month follow-up (benign/malignant) in nonsurgical cases. Tissue sampling results were reported as malignant, suspicious for malignancy, atypical, or normal. Analysis was by intention-to-treat. RESULTS: Two patients (3%) were excluded from analysis because the stricture could not be traversed with the intraductal US probe. Of the 60 remaining patients (37 men, mean age 64 years, range 27-89 years), 31 had malignant strictures (12 cholangiocarcinoma, 8 pancreatic, 5 metastatic, 3 gallbladder, 3 papilla), and 29 had benign strictures. Sphincterotomy was not required in any case to facilitate intraductal US. Fourteen patients (23%) underwent subsequent surgery including 11 with a preoperative diagnosis of resectable tumor. Endoscopic retrograde cholangiography/tissue sampling (atypia considered equivalent to benign) correctly identified 15 of 31 malignant strictures (p = 0.001) and all 29 benign strictures (p = 0.16) (accuracy 73%, sensitivity 48%, specificity 100%). The addition of intraductal US correctly identified 28 of 31 malignant strictures and 27 of 29 benign strictures (accuracy 92%, sensitivity 90%, specificity 93%). Of 11 patients with tumors who came to surgery, intraductal US correctly staged 4 (36%), understaged 5 (45%), missing metastatic lymph nodes in all cases and vascular invasion in 1 patient, and overstaged 2 (18%), with a false-positive diagnosis of metastatic lymph nodes in 1 and tumor mass in 1 patient who had no cancer at surgery. CONCLUSION: Technically easy, intraductal US is a valuable adjunct to endoscopic retrograde cholangiography/tissue sampling that increases the ability to distinguish malignant from benign strictures. Intraductal US is unsuitable for assessing lymph nodes associated with malignant strictures. 相似文献
89.
Krona C Ejeskär K Abel F Kogner P Bjelke J Björk E Sjöberg RM Martinsson T 《Oncogene》2003,22(15):2343-2351
Deletion of a part of the short arm of chromosome 1 is one of the most common chromosomal rearrangements observed in neuroblastoma (NBL) tumors and it is associated with a poor prognosis. No NBL tumor suppressor gene has yet been identified in the region. Our shortest region of overlap of deletions, ranging from marker D1S80 to D1S244, was shown to partly overlap a 500 kb region that was homozygously deleted in a NBL cell line. We have screened seven genes known to reside in or very close to this overlap consensus region, UBE4B/UFD2, KIF1B, DFFA, PGD, CORT, PEX14, and ICAT, for coding mutations in NBL tumor DNA. A few deviations from the reference sequences were identified; most interestingly being a splice site mutation that was detected in UBE4B/UFD2 in a stage 3 NBL with a fatal outcome. This mutation was neither present in the patients constitutional DNA nor in any of 192 control chromosomes analysed. Also, the expression of UBE4B/UFD2 was markedly diminished in the high-stage/poor-outcome tumors as compared to the low-stage/favorable-outcome tumors. Overall, the number of amino-acid changes in the genes of the region was low, which shows that mutations in these genes are rare events in NBL development. Given the data presented here, UBE4B/UFD2 stands out as the strongest candidate NBL tumor suppressor gene in the region at this stage. 相似文献
90.
Breast cancer and specific types of oral contraceptives: a large Norwegian cohort study 总被引:4,自引:0,他引:4
Dumeaux V Alsaker E Lund E 《International journal of cancer. Journal international du cancer》2003,105(6):844-850
The aim of our study was to examine the risk of breast cancer according to specific types of estrogens and progestagens in oral contraceptives (OCs) based on the prospective Norwegian Women and Cancer study (NOWAC). Between 1991-97 women aged 30-70 years were drawn at random from the central person register and mailed an invitation and a questionnaire. Women (102,443) were enrolled with follow-up information collected throughout 1999 by linkage with national registries of cancer, mortality and emigration based on the unique national identification number. Among the 96,362 women included in the present analysis 851 invasive breast cancer were diagnosed. The adjusted risk of breast cancer increased with 25% for ever use of OCs and the risk increased with increasing duration of use (test for trend: p = 0.007). No association between time since last use and breast cancer risk was found after stratification on duration of use. Positive trend was still found for total duration of use among women who used OCs more than 5 years ago. Second generation of OCs had an increased risk with increasing duration of use. Classifying progestagens according to chemical groups, the relative risk increased significantly with increasing cumulative dose of levonorgestrel progestagen. It was difficult to conclude for the other groups due to lack of power. In a multivariate analysis the cumulative dose for all progestagen groups were non-significant, although we observed a significant increased risk with increasing milligram-months of estrogen exposure (p = 0.002). In conclusion, the increased risk of breast cancer related with OC formulations could be due mostly to estrogen component. 相似文献