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排序方式: 共有816条查询结果,搜索用时 15 毫秒
31.
Satu Hepojoki Jussi Hepojoki Klaus Hedman Olli Vapalahti Antti Vaheri 《Journal of clinical microbiology》2015,53(2):636-640
We recently introduced a homogeneous immunoassay based on time-resolved Förster resonance energy transfer (TR-FRET) elicited by fluorophore-labeled antigen and fluorophore-labeled protein L, bound by an immunoglobulin. As the first clinical application, we employ this approach (LFRET) in serodiagnosis of Puumala hantavirus (PUUV) infection. A reference panel containing serum from individuals with acute (n = 21) or past (n = 17) PUUV infection and from PUUV-seronegative individuals (n = 20) was used to define the parameters. The clinical assay performance was evaluated with a prospectively collected serum panel (panel 2; n = 153). Based on the results for panel 1, the threshold for positivity was set at a signal level that was 3-fold over background, while those with a signal <3-fold over the background level were considered PUUV seronegative. With panel 1, 20/21 acute- and 7/10 past-infection samples induced positive signals, compared to 0/20 seronegatives. With panel 2, a positive signal was obtained in 39/40 acute- and 4/10 past-infection samples, as opposed to 7/103 seronegatives. However, after IgG depletion, 58/61 acute-infection samples were LFRET positive, while all past-infection and seronegative samples were negative, corresponding to 100% specificity and 95% sensitivity in detection of acute PUUV infection. We demonstrate that the novel immunoassay is a promising tool for rapid serodiagnosis of acute Puumala virus infection. 相似文献
32.
Analysis of the floral transcriptome uncovers new regulators of organ determination and gene families related to flower organ differentiation in Gerbera hybrida (Asteraceae) 下载免费PDF全文
Laitinen RA Immanen J Auvinen P Rudd S Alatalo E Paulin L Ainasoja M Kotilainen M Koskela S Teeri TH Elomaa P 《Genome research》2005,15(4):475-486
Development of composite inflorescences in the plant family Asteraceae has features that cannot be studied in the traditional model plants for flower development. In Gerbera hybrida, inflorescences are composed of morphologically different types of flowers tightly packed into a flower head (capitulum). Individual floral organs such as pappus bristles (sepals) are developmentally specialized, stamens are aborted in marginal flowers, petals and anthers are fused structures, and ovaries are located inferior to other floral organs. These specific features have made gerbera a rewarding target of comparative studies. Here we report the analysis of a gerbera EST database containing 16,994 cDNA sequences. Comparison of the sequences with all plant peptide sequences revealed 1656 unique sequences for gerbera not identified elsewhere within the plant kingdom. Based on the EST database, we constructed a cDNA microarray containing 9000 probes and have utilized it in identification of flower-specific genes and abundantly expressed marker genes for flower scape, pappus, stamen, and petal development. Our analysis revealed several regulatory genes with putative functions in flower-organ development. We were also able to associate a number of abundantly and specifically expressed genes with flower-organ differentiation. Gerbera is an outcrossing species, for which genetic approaches to gene discovery are not readily amenable. However, reverse genetics with the help of gene transfer has been very informative. We demonstrate here the usability of the gerbera microarray as a reliable new tool for identifying novel genes related to specific biological questions and for large-scale gene expression analysis. 相似文献
33.
Calsequestrin (CSQ) is the main Ca2? binding protein inside the sarcoplasmic reticulum (SR) of skeletal and cardiac muscle. The present study demonstrates the specific effects of different training regimens on CSQ isoform 1 (CSQ1, the primary isoform) and SR Ca2?-ATPase (SERCA1, 2) expression in various skeletal muscles of mouse. CSQ1, SERCA1, and SERCA2 protein expression was determined with Western blot in m. soleus (SOL), m. extensor digitorum longus (EDL), m. gastrocnemius (GAS), m. rectus femoris (RF), and m. tibialis anterior (TA) muscles after completing a 6-week endurance or sprint training program. Endurance training induced decrease in CSQ1 concentration in SOL (p < 0.001) and in SERCA1 levels in GAS (p < 0.05), whereas increase in CSQ1 expression was detected in EDL (p < 0.01). After sprint training the concentration of CSQ1 increased in GAS (p < 0.01) and EDL (p < 0.01). Additionally, sprint exercise induced an increase in SERCA1 in GAS (p < 0.001) and a decline in TA (p < 0.05). SERCA2 was up-regulated with sprint training in GAS (p < 0.01). Myosin heavy chain (MHC) based fibre type composition altered differently depending on the muscle and the training regimen.These results indicate that (1) diverse training strategies used affect differently CSQ1 and SERCA1 concentrations in the skeletal muscle, (2) the regulation of CSQ1 and SERCA1 does not necessary follow the fast-slow definition despite the correlation between MHC isoforms, and (3) the changes in CSQ1 concentration occur prior to SERCA1 or SERCA2. 相似文献
34.
Xiao-Yan Han W. Wang Jyrki Komulainen Satu O. A. Koskinen Vuokko Kovanen Veikko Vihko Philip C. Trackman T. E. S. Takala 《Pflügers Archiv : European journal of physiology》1999,437(6):857-864
The purpose of the study was to investigate pre-translational regulation of collagen expression after a single bout of exercise.
We analysed steady-state messenger ribonucleic acid (mRNA) levels for collagen types I, III and IV, α- and β-subunits of prolyl
4-hydroxylase and lysyl oxidase (enzymes modifying procollagen chains), and enzyme activity of prolyl 4-hydroxylase from rat
soleus muscle (MS) and the red parts of quadriceps femoris muscle (MQF) after 12 h and after 1, 2, 4, 7 and 14 days of downhill
(–13.5°) treadmill running at a speed of 17 m·min–1 for 130 min. Histological and biochemical assays revealed exercise-induced muscle damage in MQF but not MS. Steady-state
mRNA levels for the α- and β-subunits of prolyl 4-hydroxylase in MQF, lysyl oxidase in MS and MQF were increased 12 h after
running, whereas prolyl 4-hydroxylase activity did not increase until 2 days after exercise. The mRNA levels for the fibrillar
collagens (I and III) and basement membrane type IV collagen significantly increased 1 day and 12 h after exertion, respectively.
Peak mRNA levels were observed 2–4 days after running, the increases being more pronounced in MQF than in MS. No significant
changes were observed in types I or III collagen at the protein level. Strenuous downhill running thus causes an increase
in gene expression for collagen types I and III and their post-translational modifying enzymes in skeletal muscle in a co-ordinated
manner. These changes, together with the increased gene expression of type IV collagen, may represent the regenerative response
of muscle extracellular matrix to exercise-induced injury and an adaptive response to running exertion.
Received: 20 July 1998 / Received after revision: 30 November 1998 / Accepted: 26 January 1999 相似文献
35.
36.
Short-term effects of forced eccentric contractions on collagen synthesis and degradation in rat skeletal muscle 总被引:3,自引:0,他引:3
Koskinen SO Ahtikoski AM Komulainen J Hesselink MK Drost MR Takala TE 《Pflügers Archiv : European journal of physiology》2002,444(1-2):59-72
Acute downhill running has been shown to activate matrix metalloproteinase- (MMP-) 2 and to change type IV collagen concentration in some muscle types. In order to study the influence of more intense exercise on total collagen and type IV collagen concentrations, molecules regulating their synthesis and degradation were investigated after forced lengthening contractions in rat skeletal muscle. Tibialis anterior (TA) muscle of 24 male Wistar rats was subjected to 240 forced lengthening contractions. TA muscle was excised at consecutive time points (0 and 6 h, 2, 4, and 7 days) after stimulation. With immunohistochemistry, types I, III and IV collagen were located in the swollen, necrotic and regenerated fibres in a similar manner as in intact undamaged skeletal muscle fibre. An increase in the activity of prolyl 4-hydroxylase was indicative of an overall elevated collagen biosynthesis. No change was demonstrated in total collagen concentration, whereas type IV collagen concentration increased after exercise. MMP-2 and MMP-9, which are the proteins that degrade type IV collagen, elevated after exercise. In conclusion, the increase in type IV collagen concentration seems to be the result of an increase in both the synthesis and activation of degrading enzymes and their inhibitors during recovery after forced lengthening contractions. 相似文献
37.
Objective
The aim of this systematic review was to describe the effects of health coaching on adult patients with chronic diseases.Methods
The reviewers searched electronic databases and performed a manual search for studies published from 2009 to 2013. The inclusion criteria covered health coaching for adults with chronic diseases by health care professionals. The studies were original, randomized controlled trials or quasi-experimental designs.Results
Thirteen studies were selected using the inclusion criteria. The results indicate that health coaching produces positive effects on patients’ physiological, behavioral and psychological conditions and on their social life. In particular, statistically significant results revealed better weight management, increased physical activity and improved physical and mental health status.Conclusion
Health coaching improves the management of chronic diseases. Further research into the cost-effectiveness of health coaching and its long-term effectiveness for chronic diseases is needed.Practice implications Health care professionals play key roles in promoting healthy behavior and motivating good care for adults with chronic diseases. Health coaching is an effective patient education method that can be used to motivate and take advantage of a patient's willingness to change their life style and to support the patient's home-based self-care. 相似文献38.
Satu L. B. Vesalainen Pertti K. Lipponen Martti T. Talja Esko M. Alhava Kari J. Syrjnen 《International journal of cancer. Journal international du cancer》1994,58(2):303-308
The expression of proliferating cell nuclear antigen and p53 protein was analysed by immunocytochemical methods (PC10, CMI antisera) in 139 patients with T1-2MO prostatic adenocarcinomas followed-up for > 12 years. p53 protein was expressed in 21 (15%) tumours (15%), the fraction of positive nuclei being very low (mean SE, 1% ± 0.7%). Accumulation of p53 protein in epithelial cells was independent of tumour stage and Gleason score, and had no effect on prognosis. In 4 cases, p53 protein was expressed only in stromal cells. The fraction of PCNA-positive nuclei (evaluable in 116 cases) was higher in T2 than in T1 tumours (p < 0.001); furthermore, high Gleason score was positively correlated with PCNA positivity (p < 0.001). A finding of over 5% of PCNA-positive nuclei predicted progression in T and M categories and were a sign of poor outcome. The fraction of PCNA-positive stromal-cell nuclei was related to T-category with a borderline significance (p = 0.06). In a multi-variate analysis of the prognostic factors, independent predictors of survival included Gleason score (p < 0.001), fraction of PCNA-positive nuclei (p = 0.013), observation before therapy (p = 0.05), and T-category (p = 0.07) in that order of significance. The results suggest that overexpression of p53 protein is of marginal prognostic value in local prostatic adenocarcinomas, whereas direct measurement of cell proliferation by PCNA immunolabelling provides important prognostic information in T1-2MO tumours, in addition to the Gleason score. 相似文献
39.
Genetic risk determines the emergence of diabetes-associated autoantibodies in young children 总被引:5,自引:0,他引:5
Kupila A Keskinen P Simell T Erkkilä S Arvilommi P Korhonen S Kimpimäki T Sjöroos M Ronkainen M Ilonen J Knip M Simell O 《Diabetes》2002,51(3):646-651
Timing of onset of autoimmunity is a prerequisite for unmasking triggers and pathogenesis of type 1 diabetes. We followed 4,590 consecutive newborns with 8 or 3% HLA-DQB1 conferred risk for type 1 diabetes at 3-, 6-, or 12-month intervals up to 5.5 years of age. Islet cell autoantibodies (ICAs) and, in the 137 children with ICAs, insulin autoantibodies (IAAs), GAD65 autoantibodies (GADAs), and IA-2 protein autoantibodies (IA-2As) were measured. Children with high genetic risk developed ICAs more often than those with moderate risk (log-rank P = 0.0015); 85 and 91% remained ICA negative by 5 years of age, respectively. The time of appearance of biochemical autoantibodies was then compared with the appearance of ICAs. IAAs and GADAs emerged usually before ICAs (means -1.8 and -1.5 months, respectively) and IA-2As after ICAs (mean 2.0 months). Ninety-five percent of all IAAs, GADAs, and IA-2As seroconversions occurred in a cluster (-12 to 8 months) around the ICA seroconversion. We conclude that diabetes-associated autoantibodies emerged in children with predisposing HLA-DQB1 alleles after 3 months of age at a constant tempo, determined by the genetic risk level, usually in the order of IAA, GADA, ICA, and IA-2A. Seroconversion to multiple autoantibody positivity usually occurred tightly clustered in time. 相似文献
40.