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41.
Faller G Berndt R Borchard F Ell C Fuchs KH Geddert H Gossner L Günther T Kirchner T Koch HK Langner C Lüttges J May A Müller S Oberhuber G Seitz G Stolte M Tannapfel A Vieth M Walch A Rüschoff J;Working Group for Gastroenterological Pathology German Society for Pathology 《Der Pathologe》2003,24(1):9-14
There are a number of difficulties regarding the diagnosis of Barrett's mucosa and the varying grades of neoplasia that may be associated with it. It was therefore the aim of a consensus conference of the "Working Group for Gastroenterological Pathology within the German Society of Pathology" to achieve standardization regarding the following issues: definition and diagnostic criteria for Barrett's mucosa and its discrimination from intestinal metaplasia of the cardia, diagnostic criteria for intraepithelial neoplasia, number of biopsies necessary to establish the diagnosis, significance of additional immunohistochemical and/or molecular biological methods as well as importance of a second opinion in the diagnosis of intraepithelial neoplasia. 相似文献
42.
Lis Puggaard Kirsten Schroll Bjrnsbo Kirsten Kock Kurt Lüders Brit Thobo‐Carlsen Ole Lammert 《American journal of human biology》2002,14(4):486-493
This study explores to what extent the mass of internal organs may impact the age‐related decrease in energy expenditure at rest (EErest). The relationship between direct measurements of EErest in elderly women and predicted EErest based on equations deriving from the metabolic activity in tissue from younger women were also elucidated. Body composition of elderly women was measured by an impedance method. EErest was measured by the Douglas bag method after an overnight fast. These data were compared with predicted values of EErest based on equations derived from studies in younger women. The mass of internal organs was obtained from autopsy material. Young women (mean age 31.7 years, range 14–60, n = 104) and elderly women of 65 years (n = 22), 75 years (n = 26), and 85 years (n = 31) participated in this study. Autopsy data were obtained from women (n = 238) from the same birth cohorts as the elderly women who died at ages 42–87 years. EErest showed a progressive age‐related decline, which appeared to parallel a similar reduction in the mass of internal organs derived from autopsy material of women who died at the same ages. In contrast, FFM was identical in the group of 65 and 75‐year‐old women, but was lower in the 85‐year‐old women. Predicted and measured EErest revealed a strong correlation in elderly women. Modest reductions in the mass of internal organs with a high metabolic rate appear to contribute markedly to the decline in EErest observed in aging. Further, it is also possible to predict EErest from the body composition of elderly women using equations developed from younger women. Am. J. Hum. Biol. 14: 486–493, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
43.
The shufflon of Salmonella enterica serovar Typhi regulates type IVB pilus-mediated bacterial self-association 下载免费PDF全文
Previously, it was shown that type IVB pili encoded by the Salmonella enterica serovar Typhi pil operon are used to facilitate bacterial entry into human intestinal epithelial cells in vitro and that such entry is inhibited by purified prepilin (pre-PilS) protein (X.-L. Zhang, I. S. M. Tsui, C. M. C. Yip, A. W. Y. Fung, D. K.-H. Wong, X. Dai, Y. Yang, J. Hackett, and C. Morris, Infect. Immun. 68:3067-3073, 2000). The pil operon concludes with a simple shufflon, and a recombinase gene product (Rci) inverts DNA in the C-terminal region of the pilV gene to allow synthesis of two distinct PilV proteins, PilV1 and PilV2, which are presumptive minor pilus proteins. We show here that the type IVB pili mediate bacterial self-association, but only when the PilV1 and PilV2 proteins are not expressed. This may be achieved in wild-type serovar Typhi by rapid DNA inversion activity of the shufflon. We show that the inversion activity inhibits the expression of genes inserted between the 19-bp inverted repeats used for Rci-mediated recombination and that the activity of Rci increases when DNA is supercoiled. The data suggest that serovar Typhi self-associates under conditions (such as low oxygen tension in the gut) that favor DNA supercoiling. These results explain (i) the function of the serovar Typhi shufflon and (ii) why there are only two possible shufflon states, in contrast to the many possible states of other shufflon systems. The data further indicate that a very early step in serovar Typhi pathogenesis may be type IVB pilus-mediated self-association of bacteria in the anaerobic human small intestine prior to invasion of the human gut epithelium. The suggested type IVB pilus-dependent step in typhoid fever pathogenesis may partially explain the enhanced invasiveness of serovar Typhi for humans. 相似文献
44.
AIM—To measure drug adherence in
children with mild asthma receiving long term prophylactic treatment.
METHODS—Double blind randomised placebo controlled trial. Patients received inhaled budesonide 100 µg or 200 µg daily, or placebo for 27 months. All participants were asked to inhale medication or placebo from two different Turbuhalers (morning and evening) during the study. A total of 122 children (80 boys, 42 girls) aged 7-16 years with mild asthma (mean FEV1 103.7% of predicted) were included in the trial. Drug adherence was assessed by counting the number of remaining doses in the inhaler when study medication was returned at six month intervals.
RESULTS—A statistically significant and continuing decrease in measured drug adherence was found from three to nine months and then to 27 months, reaching mean values of 40.6% and 46.9% for inhaled morning and evening medication respectively. Drug adherence declined more rapidly in the placebo group (compared to active treatment); this difference became significant after two years of treatment. Children aged 9 years or less had better drug adherence during the entire study period, but the difference was only significant for the first three months of the study. Measured drug adherence was significantly higher for evening medication compared to morning medication for all study intervals after nine months.
CONCLUSION—Measured drug adherence diminishes significantly when treating children with mild asthma in a long term trial. This emphasises the importance of monitoring compliance in clinical trials.
相似文献
METHODS—Double blind randomised placebo controlled trial. Patients received inhaled budesonide 100 µg or 200 µg daily, or placebo for 27 months. All participants were asked to inhale medication or placebo from two different Turbuhalers (morning and evening) during the study. A total of 122 children (80 boys, 42 girls) aged 7-16 years with mild asthma (mean FEV1 103.7% of predicted) were included in the trial. Drug adherence was assessed by counting the number of remaining doses in the inhaler when study medication was returned at six month intervals.
RESULTS—A statistically significant and continuing decrease in measured drug adherence was found from three to nine months and then to 27 months, reaching mean values of 40.6% and 46.9% for inhaled morning and evening medication respectively. Drug adherence declined more rapidly in the placebo group (compared to active treatment); this difference became significant after two years of treatment. Children aged 9 years or less had better drug adherence during the entire study period, but the difference was only significant for the first three months of the study. Measured drug adherence was significantly higher for evening medication compared to morning medication for all study intervals after nine months.
CONCLUSION—Measured drug adherence diminishes significantly when treating children with mild asthma in a long term trial. This emphasises the importance of monitoring compliance in clinical trials.
相似文献
45.
Bang AK Carlsen E Holm M Petersen JH Skakkebaek NE Jørgensen N 《Human reproduction (Oxford, England)》2005,20(11):3109-3113
BACKGROUND: It has been suggested that finger length may correlate with function or disorders of the male reproductive system. This is based on the HOXA and HOXD genes' common embryological control of finger development and differentiation of the genital bud. The objective of this study was to explore the association between the ratio of 2nd to 4th finger length (2D:4D ratio) and testis function in a sample of young Danish men from the general population. METHODS: Semen samples and finger measurements were obtained from a total of 360 young Danish men in addition to blood samples for sex hormone analysis to describe the possible association between 2D:4D and semen and sex-hormone parameters. RESULTS: A statistically significant inverse association with the 2D:4D was found only in relation to hormone levels of FSH in the group of young men with a 2D:4D >1 (P = 0.036) and a direct association with the total sperm count in the group of young men with a 2D:4D < or = 1 (P = 0.045). CONCLUSION: The statistically significant results may be 'false positives' (type I error) rather than representing true associations. This relatively large study of young, normal Danish men shows no reliable association between 2D:4D finger ratio and testicular function. Measurements of finger lengths do not have the power to predict the testicular function of adult men. 相似文献
46.
Zhang S Guo YJ Sun SH Wang KY Wang KH Zhang Y Zhu WJ Chen ZH Jiang L 《Scandinavian journal of immunology》2005,62(4):371-377
In order to enhance the immune efficacy of DNA vaccination, experiments were conducted to investigate the regulating effects of Bacillus Calmette-Guerin (BCG)-DNA as an adjuvant on immune responses of mice against foot-and-mouth disease (FMD), Aujeszky's disease (AjD) and classical swine fever (CSF). BCG-DNA was purified from BCG by ion-exchange chromatography. Three DNA vaccines (pVSG, pVgD and pVE2) against the respective infection were constructed, and BCG-DNA was coimmunized to mice by muscle injection. The results showed that titres of specific immunoglobulin (Ig)G to the vaccines mounted remarkably in the sera of the adjuvant covaccinated mice (P < 0.01). Antibody isotype IgG2a and IgG1 also increased, respectively, in mice coimmunized with BCG-DNA compared with those of the control groups (P < 0.01). Cellular immune cytokine interferon-gamma and cytotoxic T lymphocytes were detected in coimmunized BCG-DNA groups (P < 0.05). Whereas interleukin-4, humoral immune cytokine, was not significant (P > 0.05). These results suggest that codelivery of BCG-DNA with DNA vaccines against FMD, AjD and CSF can enhance the induction of antigen-specific, especially, cell-mediated immunity. 相似文献
47.
Heinzerling L Frew AJ Bindslev-Jensen C Bonini S Bousquet J Bresciani M Carlsen KH van Cauwenberge P Darsow U Fokkens WJ Haahtela T van Hoecke H Jessberger B Kowalski ML Kopp T Lahoz CN Lodrup Carlsen KC Papadopoulos NG Ring J Schmid-Grendelmeier P Vignola AM Wöhrl S Zuberbier T 《Allergy》2005,60(10):1287-1300
Skin prick testing (SPT) is the standard method for diagnosing allergic sensitization but is to some extent performed differently in clinical centres across Europe. There would be advantages in harmonizing the standard panels of allergens used in different European countries, both for clinical purposes and for research, especially with increasing mobility within Europe and current trends in botany and agriculture. As well as improving diagnostic accuracy, this would allow better comparison of research findings in European allergy centres. We have compared the different SPT procedures operating in 29 allergy centres within the Global Allergy and Asthma European Network (GA(2)LEN). Standard SPT is performed similarly in all centres, e.g. using commercial extracts, evaluation after 15-20 min exposure with positive results defined as a wheal >3 mm diameter. The perennial allergens included in the standard SPT panel of inhalant allergens are largely similar (e.g. cat: pricked in all centres; dog: 26 of 29 centres and Dermatophagoides pteronyssinus: 28 of 29 centres) but the choice of pollen allergens vary considerably, reflecting different exposure and sensitization rates for regional inhalant allergens. This overview may serve as reference for the practising doctor and suggests a GA(2)LEN Pan-European core SPT panel. 相似文献
48.
Schmidt KL Larsen E Bangsbøll S Meinertz H Carlsen E Andersen AN 《Human reproduction (Oxford, England)》2004,19(12):2806-2810
BACKGROUND: Many male cancer survivors experience fertility problems due to antineoplastic treatment. We report the fertility outcome in 67 couples referred to assisted reproduction treatment (ART) because of male factor infertility due to cancer. METHODS: This was a retrospective study assessing the following parameters: diagnosis, cancer treatment, type of fertility treatment and type of sperm used, number of pregnancies and pregnancy outcome. RESULTS: Testicular cancer and lymphomas were the most prevalent diagnoses. Adjuvant treatment with chemo- and/or radiation therapy had been given to 90% of the men. Semen was cryopreserved in 82% of the men prior to treatment. Following antineoplastic treatment, 43% of the men had motile spermatozoa in the ejaculate, but 57% were azoospermic. A total of 151 ART cycles were performed [55 intra-uterine insemination (IUI), 82 ICSI and 14 ICSI-frozen embryo replacement (FER)]. The clinical pregnancy rate per cycle was 14.8% after IUI, 38.6% after ICSI and 25% after ICSI-FER. The corresponding delivery rates were 11.1, 30.5 and 21%. Cryopreserved semen was used in 58% of the pregnancies. The delivery rate per cycle was similar after use of fresh or cryopreserved spermatozoa. CONCLUSIONS: Male cancer survivors have a good chance of fathering a child by using either fresh ejaculated sperm or cryopreserved sperm. 相似文献
49.
Longacre A Koh JS Hsiao KK Gilligan H Fan H Patel VA Levine JS 《Journal of leukocyte biology》2004,76(5):971-984
Macrophages (mphi) from prediseased mice of the major murine models of lupus have an identical defect in cytokine expression that is triggered by serum and/or apoptotic cells. It is striking that cytokine expression in the absence of serum and apoptotic cells is equivalent to that of nonautoimmune mice. Here, we show that mphi from prediseased lupus-prone MRL/MpJ (MRL/+) or MRL/MpJ-Tnfrsf6(lpr) (MRL/lpr) mice also have reversible abnormalities in morphology, cytoskeletal organization, and adhesive properties. In the presence of serum, MRL mphi adhered in increased numbers to a variety of extracellular matrix proteins compared with mphi from two nonautoimmune strains. However, in the absence of serum, adhesion by MRL mphi was similar to that of nonautoimmune mphi. Increased adhesion by MRL mphi was also observed in the presence of apoptotic, but not necrotic, cells. The morphology and actin-staining pattern of adherent MRL mphi were consistent with reduced activity of Rho, a cytoskeletal regulator. Indeed, MRL mphi cultured in the presence of serum had markedly decreased levels of active Rho compared with nonautoimmune mphi. It is remarkable that when cultured in the absence of serum, MRL mphi displayed normal Rho activity and cytoskeletal morphology. Addition of a Rho inhibitor to normal mphi reproduced the morphologic and cytoskeletal abnormalities observed in MRL mphi. Taken together, our findings support the hypothesis that mphi from MRL and other systemic lupus erythematosus-prone mice have an apoptotic, cell-dependent, autoimmune phenotype that affects a broad range of mphi functions, including cytokine gene expression and Rho-dependent cytoskeletal regulation. 相似文献
50.