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991.
992.
Evaluation of needle biopsies and extensive clinicopathological correlation play an important role in the determination of liver allograft dysfunction occurring more than 1 year after transplantation. Interpretation of these biopsies can be quite difficult because of the high incidence of recurrent diseases that show histopathological, clinical, and serological features that overlap with each other and with rejection. Also, more than one insult can contribute to allograft injury. In an attempt to enable centers to compare and pool results, improve therapy, and better understand pathophysiological disease mechanisms, the Banff Working Group on Liver Allograft Pathology herein proposes a set of consensus criteria for the most common and problematic causes of late liver allograft dysfunction, including late-onset acute and chronic rejection, recurrent and new-onset viral and autoimmune hepatitis, biliary strictures, and recurrent primary biliary cirrhosis and primary sclerosing cholangitis. A discussion of differential diagnosis is also presented.  相似文献   
993.
994.
Studies of the risk of schizophrenia and related non-affective psychoses among individuals exposed to head injury have reported conflicting findings. The diagnostic specificity of reported associations remains unclear and the effects of sex, genetic vulnerability and timing of exposures are also uncertain. The authors used a comprehensive range of data derived from the linkage of several Swedish registers to investigate associations of head injury with schizophrenia and other non-affective psychoses. We carried out a nested case control study drawn from a cohort of 785,051 men and women born between 1973 and 1980. After head injury exposure, there was a small increase in the risk (OR 1.37 (CI 1.14-1.66)) of non-schizophrenic, non-affective psychoses but not schizophrenic disorder (OR 1.10 CI 0.82 to 1.47). There was no critical period effect for exposures in early childhood, the association with non-affective psychosis being observed only in those exposed to head injury after age 10. There was no evidence that associations differed in males and females or in those with, and those without, a family history of psychosis. We conclude that it is unlikely that head injury causes schizophrenia. There is a small but significant risk of non-schizophrenic psychotic disorders but this is not associated with early age of injury or family history of psychosis. Further research is needed to clarify the potential roles of social and biological intermediary factors.  相似文献   
995.
OBJECTIVE: The objective of this study was to evaluate a high spatial resolution 3-dimensional (3D) contrast-enhanced magnetic resonance (CE-MR) venography protocol for evaluation of intracranial venous system using highly accelerated parallel imaging at 3.0 T. MATERIALS AND METHODS: Ten patients (4 male, 6 female; age, 38-76 years) with suspected cerebrovascular disease were prospectively studied on a 32-channel 3.0 T MR system. After a single intravenous contrast injection, high spatial resolution 3D CE-MR angiography of the entire supraaortic arteries was performed followed immediately by 3D cerebral CE-MR venography. By using a fast 3D gradient-recalled-echo sequence with elliptic centric k-space ordering and highly accelerated parallel acquisition (acceleration factor 3 and 2 in phase and slice encoding direction, respectively), 3D cerebral CE-MR venography was acquired with voxel dimensions of 0.7 x 0.7 x 0.8 mm in 24 seconds. Image evaluation was performed independently by 2 neuroradiologists for overall image quality, presence of noise, and artifacts. The image quality of 30 venous segments was evaluated in each subject using a 1 to 4 scoring scale. In 2 patients, catheter angiography was available for correlation. Statistical analysis of data was performed by using Wilcoxon rank sum test and kappa coefficient. RESULTS: All studies were determined to be of diagnostic image quality by both observers. The majority (90%) of cerebral venous segments were evaluated to be of diagnostic image quality (median, 3; range, 3-4) by both readers and with excellent interobserver agreement (kappa = 0.86; 95% confidence interval, 0.79-0.93). One meningioma invading the superior sagittal sinus and one superior sagittal sinus fistula were detected subsequently confirmed by conventional angiography. CONCLUSION: High spatial resolution 3D cerebral CE-MR venography is feasible and promising. Using a 32-channel 3.0 T system combined with multichannel array coils effectively supports highly accelerated parallel imaging, enabling subsequent acquisition of both high spatial resolution CE-MR angiography and CE-MR venography after a single contrast injection without impairing the image quality. More extensive clinical studies are warranted to establish the range of applications and confirm the accuracy of this technique.  相似文献   
996.
Aims: Toll-like receptor 4 (TLR4) is the major endotoxin signalling receptor of the innate immune system and is required for efficient recognition of bacterial infections. Here, we analysed a possible association between the TLR4 variant Asp299Gly and disease outcome in children with invasive meningococcal disease.
Methods: In total, 197 children with invasive meningococcal disease were analysed for the TLR4 Asp299Gly variant. Genotyping results were correlated with mortality, the frequency of ventilation support, application of inotropic substances, skin grafting, and limb loss.
Results: The overall Asp299Gly allele frequency was 9.4%. Detection of a heterozygous Asp299Gly TLR4 mutation was significantly associated with fatal outcome (non-survivor group: 31.6% vs. survivor group: 12.1%; p = 0.021) and was even more pronounced in patients with disease onset less than 24 months of age (non-survivor group: 42.8% vs. survivor group: 10.2%; p = 0.006). In this age group, ventilation support was also more frequent in patients with the Asp299Gly genotype (37.5% vs. 6.2%).
Conclusion: Our data suggest that the heterozygous TLR4 Asp299Gly genotype is associated with an increased mortality in children with invasive meningococcal disease.  相似文献   
997.
998.
HPV testing is a valuable tool in cervical cancer screening and efficacy assessment of HPV vaccines. Concordance of specimens from three sites for detection of HPV DNA in the female genital tract was evaluated. At a single visit, the following specimens were collected: an endo‐ecto‐cervical swab (EEC), labial/vulvar/perineal/perianal swab (LVPP) and cervicovaginal lavage (CVL). Specimens were evaluated with HPV6, HPV11, HPV16, and HPV18 type‐ and gene‐specific PCR assays. Of the 898 women evaluated at baseline, 232 were HPV PCR positive in at least one specimen. Of these, for HPV6, HPV11, HPV16, and HPV18, respectively, throughout: (a) 70.4%, 40.0%, 65.3%, and 64.1% tested three‐site positive; (b) 13.6%, 30.0%, 19.7%, and 18.8% tested two‐site positive; and (c) 16.4%, 30.0%, 15.0%, and 17.2% tested single‐site positive. For patients who tested single‐site positive for HPV6, HPV11, HPV16, or HPV18, respectively, the specimen was: LVPP in 92.3%, 33.3%, 68.2%, and 72.7%; EEC in 0.0%, 33.3%, 18.2%, and 9.1%; and CVL in 7.7%, 33.3%, 13.6%, and 18.2%. Combining results of swab specimens together increases detection of HPV6, HPV11, HPV16, and HPV 18, respectively, to 98.7%, 90.0%, 97.9%, and 96.9%. HPV DNA is detectable from all three sites using type‐specific PCR assays; most women who tested positive for a given HPV type were positive for that type in all three specimens. J. Med. Virol. 81:1620–1626, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
999.
1000.
This article reviews the growing use of online self-help and mutual aid groups and explores the helping mechanisms and content of an online self-help group for issues related to disability. Messages were downloaded from the group and coded by raters into helping categories to examine the extent to which therapeutic processes were found. The categories included both task and socioemotional-related functions. The study found that the group provided many of the processes used in face-to-face self-help and mutual aid groups, with an emphasis on mutual problem solving, information sharing, expression of feelings, catharsis, and mutual support and empathy. Implications for social work and health care providers and the need for further research are discussed.  相似文献   
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