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961.
Educators have long lamented the tendency of students to engage in rote memorization in preparation for tests rather than engaging in deep learning where they attempt to gain meaning from their studies. Rote memorization driven by objective exams has been termed a steering effect. Progress testing (PT), in which a comprehensive examination sampling all of medicine is administered repeatedly throughout the entire curriculum, was developed with the stated aim of breaking the steering effect of examinations and of promoting deep learning. PT is an approach historically linked to problem-based learning (PBL) although there is a growing recognition of its applicability more broadly. The purpose of this article is to summarize the salient features of PT drawn from the literature, provide a critical review of these features based upon the same literature and psychometric considerations drawn from the Standards for Educational and Psychological Testing and provide considerations of what should be part of best practices in applying PT from an evidence-based and a psychometric perspective.  相似文献   
962.
The tumour microenvironment in classical Hodgkin's lymphoma (cHL) is characterised by a minor population of neoplastic Hodgkin and Reed–Sternberg cells within a heterogeneous background of non‐neoplastic bystanders cells, including mast cells. The number of infiltrating mast cells in cHL has been reported to correlate with poor prognosis. We used immunohistochemistry to assess the degree of tumour‐infiltrating mast cells in cHL tissue microarrays and correlated this with clinico‐pathological features and prognosis in a cohort of homogeneously treated patients with Hodgkin's disease. A high degree of tumour mast cells was associated with nodular sclerosis (NS) subtype histology (P = 0.0002). Moreover, the number of mast cells was inversely correlated with the numbers of CD68+ and CD163+ macrophages (P = 0.0001 and P = 0.003, respectively) and with the number of granzyme+ cytotoxic cells (P = 0.004). The degree of mast cell infiltration was not a prognostic factor in cHL of nodular sclerosis subtype. In contrast, in mixed cellularity cHL a high number of intratumoral mast cells correlated with significantly poorer outcome both in terms of overall (P = 0.03) and event‐free survival (P = 0.01). Further studies are warranted into the biological mechanisms underlying this adverse outcome and their possible therapeutic implications.  相似文献   
963.
Campylobacter concisus is an emerging pathogen associated with gastrointestinal disorders such as gastroenteritis and inflammatory bowel diseases (IBD), but the species is also found in healthy subjects. The heterogeneous genome of C. concisus increases the likelihood of varying virulence between strains. Flagella motility is a crucial virulence factor for the well‐recognized Campylobacter jejuni; therefore, this study aimed to analyze the motility of C. concisus isolated from saliva, gut biopsies, and feces of patients with IBD, gastroenteritis, and healthy subjects. The motility zones of 63 isolates from 52 patients were measured after microaerobic growth in soft‐agar plates for 72 hours. The motility of C. concisus was significantly lower than that of Campylobacter jejuni and Campylobacter fetus subsp. fetus. The motility of C. concisus varied between isolates (4–22 mm), but there was no statistical significant difference between isolates from IBD patients and healthy subjects (p = 0.14). A tendency of a larger motility zones was observed for IBD gut mucosa isolates, although it did not reach statistical significance (p = 0.13), and no difference was found between oral or fecal isolates between groups. In conclusion, the varying motility of C. concisus could not be related to disease outcome or colonization sites.  相似文献   
964.
The aim of this systematic review is to summarise quantitative studies in occupational settings observing the association between Information communication technology (ICT) and stress, and burnout, considering age as an effect modifier. A systematic review using PRISMA guidelines was conducted through the following bibliographic databases: PubMed, Web of Science, Psycinfo, and the Cochrane Library. Inclusion criteria were occupational settings and content relevant to our research question. Risk of bias was assessed using the Newcastle–Ottawa scale. Two interventional, 4 cohorts, and 29 cross-sectional studies were found. ICT use in occupational settings was associated with stress seen in cross-sectional studies, but not in interventional studies. There was a concordant association with ICT and burnout in different study designs. Overall, there were no linear trends between age and technostress. We suggest that the observed associations were mostly present in the middle-aged working population and that these associations need to be supported in further studies.  相似文献   
965.
966.
Physicians walk a fine line when deciding whether to recommend that youngsters who have only one of a paired set of organs participate in sports. Increasingly, courts are ruling in favor of letting the athlete compete. To make the best decision for the health of their patients, physicians can learn about the risks specific sports pose and the protective gear that's available— and pass that information on to patients and their families.  相似文献   
967.
968.
Abstract

Background/Objective: Few studies have examined the prevalence of visceral pain in persons with spinalcord injury (SCI), and virtually no studies have looked at the relationship between visceral pain and selfreportedquality of life. We examined the frequency of reported visceral pain at 5, 10, and 15 years afterinjury to determine whether the presence of visceral pain is related to quality of life, and to determine towhat extent visceral pain should be of concern to clinicians treating patients with SCI.

Methods: Visceral pain and quality of life in persons with SCI were compared from a combined CraigHospital and National Model SCI Systems database at 5 (N=33), 10 (N=132), and 15 (N=96) years afterinjury.

Results: The rates of visceral pain increased at each measurement (10% at year 5, 22% at year 10, and 32%at year 15); although these numbers reflect cross-sectional data, they do show a clear statistical change.Only a limited true longitudinal sample was available, but at 10 years after injury, individuals who hadreported visceral pain at any time reported a significantly lower quality of life than those never experiencingvisceral pain, F1,188 = 3.95, P <0.05.

Conclusions: Although visceral pain may not be as prevalent as the more researched neuropathic andmusculoskeletal subtypes of pain, it may account for a higher percentage of people with SCI who report painthan previously recognized. More quantitative and longitudinal research is needed to examine therelationship of visceral pain with overall quality of life and to pursue interventions.  相似文献   
969.
The purpose of the present study was to examine the clinical utility of the Normative Studies Research Project test battery for detecting dementia with a known vascular component. The study compared 65 patients who had both suffered a stroke and met the DSM-IV criteria for dementia with 86 older medical patients who were cognitively intact. Multivariate analysis of covariance results demonstrated that these two groups had significantly different means on tests within the battery even after controlling for the influence of demographic variables. Logistic regression results demonstrated positive predictive value of 81.36%, negative predictive value of 85.23%, and an overall correct classification rate of 83.67%.  相似文献   
970.
Magnetic resonance phase contrast angiography (MRA) is the gold standard for blood flow evaluation. Spectral Doppler ultrasound (SDU) is the first clinical choice, although the method is angle dependent. Vector flow imaging (VFI) is an angle-independent ultrasound method. The aim of the study was to compare VFI- and SDU-estimated peak systolic velocities (PSV) of the common carotid artery (CCA) with PSV obtained by MRA. Furthermore, intra- and inter-observer agreement was determined. MRA estimates were significantly different from SDU estimates (left CCA: p?<?0.001, right CCA: p?<?0.001), but not from VFI estimates (left CCA: p?=?0.28, right CCA: p?=?0.18). VFI measured lower PSV in both CCAs compared with SDU (p?<?0.001) with improved precision (VFI: left: 24%, right: 18%; SDU: left 38%, right: 23%). Intra- and inter-observer agreement was almost perfect for VFI and SDU (inter-observer correlation coefficient: VFI 0.88, SDU 0.91; intra-observer correlation coefficient: VFI 0.96, SDU 0.97). VFI is more accurate than SDU in evaluating PSV compared with MRA.  相似文献   
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