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排序方式: 共有515条查询结果,搜索用时 15 毫秒
91.
MA Karsdal I Byrjalsen AC Bay-Jensen K Henriksen BJ Riis C Christiansen 《BMC musculoskeletal disorders》2010,11(1):125
Background
Osteoarthritis (OA) involves changes in both bone and cartilage. These processes might be associated under some circumstances. This study investigated correlations between bone and cartilage degradation in patients with OA as a function of sex, Kellgren-Lawrence (KL) score, Body Mass Index (BMI), oral salmon calcitonin (sCT) treatment and diurnal variation. 相似文献92.
KM Kanal NJ Hangiandreou AM Sykes HE Eklund PA Araoz JA Leon BJ Erickson 《Journal of digital imaging》2001,14(1):30-37
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner. 相似文献
93.
Three oral fluid collection devices (OraSure, Omni-SAL and Oracol) were compared in terms of the quality of oral fluid collected by each device for antibody testing and their acceptability to participants. Participants (143 children aged 3.5-5 y from North Hertfordshire, UK, who had recently received DTaP and MMR vaccination) were randomised to use one of the three types of collection device. Oral fluid was collected by a parent who completed a short questionaire recording information on ease of use and willingness to use the device again. A matching serum sample was collected by a nurse. Oral fluid samples were screened for total IgG and IgM by ELISA and for rubella specific IgG and parvovirus specific IgG by radioimmunoassay. Serum samples were screened for rubella specific IgG and parvovirus B19 specific IgG by ELISA. 87.4% (125) of participants provided a matching oral fluid and serum sample. Of these, 100% (125) and 10.4% (13) had serum IgG specific for rubella and parvovirus B19, respectively. The Oracol device provided oral fluid samples with the highest geometric mean titres of total IgG and IgM and with rubella specific IgG results which correlated most closely with those of matching sera. A higher proportion of parents found the Oracol and OraSure devices easier to use than the Omni-SAL (P<0.001) and the proportion who would not take another test was higher for the Omni-SAL than for the Oracol or Orasure. Oral fluid samples collected by each of the devices gave qualitative results acceptable for surveillance and epidemiological studies of rubella and parvovirus B19. The highest quality oral fluid sample for antibody testing in terms of total IgG and IgM concentration and rubella specific IgG concentration was collected by the Oracol. The acceptability to participants of both the Oracol and OraSure was high. As the cheapest device available, the Oracol is the preferred oral fluid collection device for studies involving children in the UK. 相似文献
94.
95.
患者为1例39岁女性,患T/NK细胞淋巴瘤,在外周血异基因干细胞移植后15天,发生环孢素A(CSA)毒性相关的微血管病溶血性贫血(MAHA).因血清肌酐从移植前的0.4mg/dL,上升至移植后第9和15天的1.0和2.9 mg/dL.故停用CSA. 相似文献
96.
97.
98.
During computed tomography (CT) pelvimetry of two pregnant women, bony abnormalities of the fetuses were noted on the scout images that were not confirmed at delivery. To explore the cause of these artifacts, specimen long bones were manipulated in various ways during CT scout imaging. Artifacts like those seen during in vivo imaging were found to be caused by motion of the object. The CT scout view is an example of an image produced by a digital system that uses a scanning beam. This type of digital system is being used for several types of body imaging including screening for scoliosis and chest radiography. Attention to motion artifacts should decrease diagnostic errors and aid further development of these systems. 相似文献
99.
In human immune deficiency virus (HIV)-seropositive hemophilia patients, a low number of CD4 + lymphocytes is found, as well as a low CD4+/CD8+ ratio. In previous studies, it has been shown that antigen- specific T-helper cell (CD4+) function was present and no excessive antigen-specific T-suppressor cell (CD8+) function could be demonstrated. In this report, we studied another activity of CD4+ cells, namely the capacity to induce T-suppressor cell activity. The results clearly show a selective dysfunction of CD4+ suppressor-inducer (Tsi) cell function. Since these HIV-seropositive hemophilia patients showed the presence of activated B cells in the peripheral circulation refractory to antigen-specific T-helper cell signals and secreting specific antibodies spontaneously, we raised the hypothesis that the activated B cells in the patients activate the Tsi cells in vivo. This constant activation leads to a functional exhaustion of the Tsi cell pool. 相似文献
100.
A gene recently inactivated in human defines a new olfactory receptor family in mammals 总被引:6,自引:3,他引:3
Rouquier S; Friedman C; Delettre C; van den Engh G; Blancher A; Crouau-Roy B; Trask BJ; Giorgi D 《Human molecular genetics》1998,7(9):1337-1345
The olfactory receptor (OR) gene family constitutes one of the largest
multigene families and is distributed among many chromosomal sites in the
human genome. Four OR families have been defined in mammals. We previously
demonstrated that a high fraction of human OR sequences have incurred
deleterious mutations, thus reducing the repertoire of functional OR genes.
In this study, we have characterized a new OR gene, 912-93, in primates.
This gene is unique and it defines a new OR family. It localizes to human
chromosome 11q11-12 and at syntenical sites in other hominoids. The
sequence marks a previously unrecognized rearrangement of pericentromeric
material from chromosome 11 to the centromeric region of gibbon chromosome
5. The human gene contains a nonsense point mutation in the region
corresponding to the extracellular N-terminus of the receptor. This
mutation is present in humans of various ethnic groups, but is absent in
apes, suggesting that it probably appeared during the divergence of humans
from other apes, <4 000 000-5 000 000 years ago. A second mutation, a
frameshift at a different location, has occurred in the gorilla copy of
this gene. These observations suggest that OR 912-93 has been recently
silenced in human and gorilla, adding to a pool of OR pseudogenes whose
growth may parallel a reduction in the sense of smell in primates.
相似文献