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111.
112.
Donor sclera‐wrapped acrylic orbital implants following enucleation: experience in 179 patients in the Netherlands 下载免费PDF全文
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114.
Jaco Joubert Sunette Joubert Jacques Raubenheimer Vernon Louw 《Transfusion and apheresis science》2014,50(3):25-32
This audit in chronically anaemic adult patients assesses whether red cell concentrate is transfused according to guidelines, and evaluates the impact of training interventions, compared with a similar audit conducted in 2010. Retrospectively, 25 transfusion episodes were audited for appropriateness, the investigation of anaemia, threshold achievement, wastage, and informed consent. After training interventions, a further 25 episodes were prospectively analysed. The effects of current training interventions were not shown to have a statistically significant impact. Compared to a 2010 audit, however, a statistically significant improvement was demonstrated in transfusion practice, suggesting that training interventions may lead to sustainable long-term improvements. 相似文献
115.
Predicting serious bacterial infection in young children with fever without apparent source 总被引:1,自引:0,他引:1
SE Bleeker KGM Moons G Derksen-Lubsen DE Grobbee HA Moll 《Acta paediatrica (Oslo, Norway : 1992)》2001,90(11):1226-1231
The aim of this study was to design a clinical rule to predict the presence of a serious bacterial infection in children with fever without apparent source. Information was collected from the records of children aged 1-36 mo who attended the paediatric emergency department because of fever without source (temperature > or = 38 degrees C and no apparent source found after evaluation by a general practitioner or history by a paediatrician). Serious bacterial infection included bacterial meningitis, sepsis, bacteraemia, pneumonia, urinary tract infection, bacterial gastroenteritis, osteomyelitis and ethmoiditis. Using multivariate logistic regression and the area under the receiver operating characteristic curve (ROC area), the diagnostic value of predictors for serious bacterial infection was judged, resulting in a risk stratification. Twenty-five percent of the 231 patients enrolled in the study (mean age 1.1 y) had a serious bacterial infection. Independent predictors from history and examination included duration of fever, poor micturition, vomiting, age, temperature < 36.7 degrees C or > or = 40 degrees C at examination, chest-wall retractions and poor peripheral circulation (ROC area: 0.75). Independent predictors from laboratory tests were white blood cell count, serum C-reactive protein and the presence of >70 white blood cells in urinalysis (ROC area: 0.83). The risk stratification for serious bacterial infection ranged from 6% to 92%. CONCLUSION: The probability of a serious bacterial infection in the individual patient with fever without source can be estimated more precisely by using a limited number of symptoms, signs and laboratory tests. 相似文献
116.
Morten Mørk Shona Pedersen Jaco Botha Sigrid Marie Lund 《Scandinavian journal of clinical and laboratory investigation》2016,76(5):349-360
Background: Nanoparticle tracking analysis (NTA) and tunable resistive pulse sensing (TRPS) enable measurement of extracellular vesicles (EVs) in blood plasma but also measure other particles present in plasma. Complete isolation of EVs from similarly sized particles with full EV recovery is currently not possible due to limitations in existing isolation techniques.Aim: This study aimed to evaluate preanalytical, analytical, and biological variation of particle measurements with NTA and TRPS on blood plasma.Methods: Blood from 20 healthy subjects was sampled in the fasting and postprandial state. Platelet free plasma (PFP) was analyzed immediately and after a freeze-thaw cycle. Additionally, the effect of prandial state and a freeze-thaw cycle on EV-enriched particle fractions obtained via size-exclusion chromatography (SEC) was examined.Results: We observed analytical linearity in the range of 1.0–10.0?×?108 particles/mL for NTA and 1.0?×?108–1.8?×?109 particles/mL for TRPS. The analytical variation was generally below 10%. A considerable intra- and inter-individual variation was demonstrated with estimated reference intervals of 1.4?×?1011–1.2?×?1012 particles/mL for NTA and 1.8?×?108–1.6?×?109 particles/mL for TRPS. Food intake and to a lesser extent a freeze-thaw cycle affected particle populations in PFP and, similarly, in EV-enriched fractions.Conclusion: In this study NTA and TRPS enabled acceptably precise concentration and size measurement of submicron particles in PFP. An appreciable intra- and inter-individual biological variation was observed. In studies on particle populations in PFP or EV-enriched fractions, we recommend analysis of fresh, fasting samples. 相似文献
117.
Bulkmans NW Bleeker MC Berkhof J Voorhorst FJ Snijders PJ Meijer CJ 《International journal of cancer. Journal international du cancer》2005,117(2):177-181
High-risk human papillomavirus (hrHPV) types are causally related to cervical cancer and its high-grade precursor lesions. The risk posed by the different hrHPV types for the development of cervical intraepithelial neoplasia grade 2 or worse (> or =CIN2) needs to be established. Here, we present the hrHPV type-distribution in relation to cytology and histology for women participating in a cervical screening program. From 44,102 women who participated in a population-based cervical screening program in the Netherlands, 2,154 hrHPV GP5+/6+ PCR positive women were recruited to determine the distribution of 14 hrHPV types by reverse line blotting of GP5+/6+ PCR products. For each HPV type, associations with cytology and histologically confirmed > or =CIN2 were measured by odds ratios. HPV types 16 and 33 were more prevalent in women, amongst those containing a single hrHPV type, with moderate dyskaryosis or worse (>BMD) than in women with normal cytology, but only in case of underlying > or =CIN2 (OR 4.10, 95%CI 2.98-5.64 and OR 2.68, 95%CI 1.39-5.15, respectively). Similar results were obtained for women with double infections (OR 3.29, 95% CI 1.61-6.75 and OR 4.37, 95% CI 1.17-16.34). Coexisting types did not influence the prevalence of > or =CIN2 in HPV 16 or 33 positive women. The increased prevalence of type 16 and 33 in hrHPV positive women with > or =CIN2, compared to women with normal cytology, suggests that infection with these types confers an increased risk for development of > or =CIN2. Distinguishing these types may therefore have implications for future cervical screening strategies. 相似文献
118.
Bleeker MC Hogewoning CJ Voorhorst FJ van den Brule AJ Snijders PJ Starink TM Berkhof J Meijer CJ 《International journal of cancer. Journal international du cancer》2003,107(5):804-810
Penile HPV-associated lesions are frequently seen in male sexual partners of women with CIN. The natural course and clinical significance of these lesions are unclear. Women with CIN and their male sexual partners were randomized for condom use (condom group n = 68, noncondom group n = 68). Males were screened for the presence of penile lesions, i.e., flat lesions, papular lesions and condylomata acuminata, and of HPV in their penile swabs by PCR testing. Median follow-up time was 13.1 months (range 2.9-57.4). The outcome of our study was clinical regression of penile lesions defined as disappearance of lesions at penoscopy. Potentially prognostic factors, i.e., HPV status, lesion type and age, were studied as well. Outcomes were assessed in 57 men of the condom group and in 43 men of the noncondom group. Condom use shortened the median time to regression of flat penile lesions (7.4 months condom group vs. 13.9 months noncondom group; HR = 2.1, 95% CI 1.2-3.7). This effect was not found for papular lesions (HR = 0.5, 95% CI 0.1-2.8). HPV-negative men showed a significantly shorter median time to regression of flat lesions (3.8 months) compared to men with either HPV-positive status (8.5 months; HR = 0.4, 95% CI 0.2-0.9) or inconsistent HPV status (13.1 months; HR = 0.2, 95% CI 0.1-0.6). Regression of flat penile lesions is HPV-dependent and accelerated by condom use. This effect is probably the result of blocking viral transmission between sexual partners. 相似文献
119.
Steyn M N'Da DD Breytenbach JC Smith PJ Meredith S Breytenbach WJ 《The Journal of pharmacy and pharmacology》2011,63(2):278-286
Objectives The aim of this study was to synthesize a series of ethylene glycol ether derivatives of the antimalarial drug artemisinin, determine their values for selected physicochemical properties and evaluate their antimalarial activity in vitro against Plasmodium falciparum strains. Methods The ethers were synthesized in a one‐step process by coupling ethylene glycol moieties of various chain lengths to carbon C‐10 of artemisinin. The aqueous solubility and log D values were determined in phosphate buffered saline (pH 7.4). The derivatives were screened for antimalarial activity alongside artemether and chloroquine against chloroquine‐sensitive (D10) and moderately chloroquine‐resistant (Dd2) strains of P. falciparum. Key findings The aqueous solubility within each series increased as the ethylene glycol chain lengthened. The IC50 values revealed that all the derivatives were active against both D10 and Dd2 strains. All were less potent than artemether irrespective of the strain. However, they proved to be more potent than chloroquine against the resistant strain. Compound 8 , featuring three ethylene oxide units, was the most active of all the synthesized ethers. Conclusions The conjugation of dihydroartemisinin to ethylene glycol units of various chain lengths through etheral linkage led to water‐soluble derivatives. The strategy did not result in an increase of antimalarial activity compared with artemether. It is nevertheless a promising approach to further investigate and synthesize water‐soluble derivatives of artemisinin that may be more active than artemether by increasing the ethylene glycol chain length. 相似文献
120.
Pauline A. J. Mendelaar Jaco Kraan Mai Van Leonie L. Zeune Leon W. M. M. Terstappen Esther Oomende Hoop John W. M. Martens Stefan Sleijfer 《Molecular oncology》2021,15(1):116
Circulating tumor cells (CTCs) in the blood of cancer patients are of high clinical relevance. Since detection and isolation of CTCs often rely on cell dimensions, knowledge of their size is key. We analyzed the median CTC size in a large cohort of breast (BC), prostate (PC), colorectal (CRC), and bladder (BLC) cancer patients. Images of patient‐derived CTCs acquired on cartridges of the FDA‐cleared CellSearch® method were retrospectively collected and automatically re‐analyzed using the accept software package. The median CTC diameter (μm) was computed per tumor type. The size differences between the different tumor types and references (tumor cell lines and leukocytes) were nonparametrically tested. A total of 1962 CellSearch® cartridges containing 71 612 CTCs were included. In BC, the median computed diameter (CD) of patient‐derived CTCs was 12.4 μm vs 18.4 μm for cultured cell line cells. For PC, CDs were 10.3 μm for CTCs vs 20.7 μm for cultured cell line cells. CDs for CTCs of CRC and BLC were 7.5 μm and 8.6 μm, respectively. Finally, leukocytes were 9.4 μm. CTC size differed statistically significantly between the four tumor types and between CTCs and the reference data. CTC size differences between tumor types are striking and CTCs are smaller than cell line tumor cells, whose size is often used as reference when developing CTC analysis methods. Based on our data, we suggest that the size of CTCs matters and should be kept in mind when designing and optimizing size‐based isolation methods.
Abbreviations
- ACCEPT
- Automated CTC Classification, Enumeration, and PhenoTyping software
- BC
- breast cancer
- BLC
- bladder cancer
- CD
- computed diameter
- CEL
- cultured tumor cell (cell line)
- CK
- cytokeratin
- CRC
- colorectal cancer
- CTC‐L
- circulating tumor cells derived from cerebrospinal fluid (liquor)
- CTCs
- circulating tumor cells
- DAPI
- 4′6‐diamidino‐2‐phenylindole
- EMT
- epithelial–mesenchymal transition
- EpCAM
- epithelial cell adhesion molecule
- IQR
- interquartile range
- KW test
- Kruskal–Wallis test
- MWU test
- Mann–Whitney U test
- NCR
- nucleus/cytoplasm ratio
- P2A
- perimeter to area
- PC
- prostate cancer
- TIF
- tagged Image Format files
- TXT
- text file
- μm
- micrometer
- µm2
- square micrometers