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91.
The cytogenetic effects of trifluoperazine have been studied in male Swiss albino mice using the micronucleus test, chromosomal analysis in germ cells and a sperm morphology assay. The mice were treated by gavage with 80, 120 or 160 micrograms trifluoperazine/kg, divided in each case into two equal doses given 24 hr apart. The dose levels were selected on the basis of standard human therapeutic dosage. Compared with the findings in control mice dosed with distilled water, there were significant increases in the frequency of micronuclei, of chromosomal aberrations in the spermatocytes and of abnormal sperms, at all the levels of trifluoperazine treatment. 相似文献
92.
Lara Schorn Anna Sine Karin Berr Jrg Handschel Rita Depprich Norbert R. Kübler Christoph Sproll Majeed Rana Julian Lommen 《Materials》2022,15(14)
Alloplastic and xenogeneic bone grafting materials are frequently used for bone augmentation. The effect of these materials on precursor cells for bone augmentation is yet to be determined. The aim of this study was to ascertain, in vitro, how augmentation materials influence the growth rates and viability of human unrestricted somatic stem cells. The biocompatibility of two xenogeneic and one alloplastic bone graft was tested using human unrestricted somatic stem cells (USSCs). Proliferation, growth, survival and attachment of unrestricted somatic stem cells were monitored after 24 h, 48 h and 7 days. Furthermore, cell shape and morphology were evaluated by SEM. Scaffolds were assessed for their physical properties by Micro-CT imaging. USSCs showed distinct proliferation on the different carriers. Greatest proliferation was observed on the xenogeneic carriers along with improved viability of the cells. Pore sizes of the scaffolds varied significantly, with the xenogeneic materials providing greater pore sizes than the synthetic inorganic material. Unrestricted somatic stem cells in combination with a bovine collagenous bone block seem to be very compatible. A scaffold’s surface morphology, pore size and bioactive characteristics influence the proliferation, attachment and viability of USSCs. 相似文献
93.
Athar Khalil Khalil Al Handawi Zeina Mohsen Afif Abdel Nour Rita Feghali Ibrahim Chamseddine Michael Kokkolaras 《Viruses》2022,14(7)
The rapid spread of the coronavirus disease COVID-19 has imposed clinical and financial burdens on hospitals and governments attempting to provide patients with medical care and implement disease-controlling policies. The transmissibility of the disease was shown to be correlated with the patient’s viral load, which can be measured during testing using the cycle threshold (Ct). Previous models have utilized Ct to forecast the trajectory of the spread, which can provide valuable information to better allocate resources and change policies. However, these models combined other variables specific to medical institutions or came in the form of compartmental models that rely on epidemiological assumptions, all of which could impose prediction uncertainties. In this study, we overcome these limitations using data-driven modeling that utilizes Ct and previous number of cases, two institution-independent variables. We collected three groups of patients (n = 6296, n = 3228, and n = 12,096) from different time periods to train, validate, and independently validate the models. We used three machine learning algorithms and three deep learning algorithms that can model the temporal dynamic behavior of the number of cases. The endpoint was 7-week forward number of cases, and the prediction was evaluated using mean square error (MSE). The sequence-to-sequence model showed the best prediction during validation (MSE = 0.025), while polynomial regression (OLS) and support vector machine regression (SVR) had better performance during independent validation (MSE = 0.1596, and MSE = 0.16754, respectively), which exhibited better generalizability of the latter. The OLS and SVR models were used on a dataset from an external institution and showed promise in predicting COVID-19 incidences across institutions. These models may support clinical and logistic decision-making after prospective validation. 相似文献
94.
Andrej M Kielbassa Ina Ulrich Rita Schmidl Christoph Schller Wilhelm Frank Vanessa D Werth 《International journal of oral science》2017,9(2)
The aim of this ex vivo study was to evaluate the infiltration capability and rate of microleakage of a low-viscous resin infiltrant combined with a flowable composite resin (RI/CR) when used with deproteinised and etched occlusal subsurface lesions (International Caries Detection and Assessment System code 2). This combined treatment procedure was compared with the exclusive use of flowable composite resin (CR) for fissure sealing. Twenty premolars and 20 molars revealing non-cavitated occlusal carious lesions were randomly divided into two groups and were meticulously cleaned and deproteinised using NaOCl (2%). After etching with HCl (15%), 10 premolar and 10 molar lesions were infiltrated (Icon/DMG; rhodamine B isothiocyanate (RITC)-labelled) followed by fissure sealing (G-?nial Flo/GC; experimental group, RI/CR). In the control group (CR), the carious fissures were only sealed. Specimens were cut perpendicular to the occlusal surface and through the area of the highest demineralisation (DIAGNOdent pen, KaVo). Using confocal laser-scanning microscopy, the specimens were assessed with regard to the percentage of caries infiltration, marginal adaption and internal integrity. Within the CR group, the carious lesions were not infiltrated. Both premolar (57.9%± 23.1%) and molar lesions (35.3%± 22.1%) of the RI/CR group were uniformly infiltrated to a substantial extent, albeit with significant differences (P=0.034). Moreover, microleakage (n=1) and the occurrence of voids (n=2) were reduced in the RI/CR group compared with the CR group (5 and 17 specimens, respectively). The RI/CR approach increases the initial quality of fissure sealing and is recommended for the clinical control of occlusal caries. 相似文献
95.
Clinical Benefit in Response to Palbociclib Treatment in Refractory Uterine Leiomyosarcomas with a Common CDKN2A Alteration 下载免费PDF全文
96.
de Faria DE Borges LV Peters VM Reis JE Ribeiro LC de Cássia da Silveira E Sá R Guerra Mde O 《Phytotherapy research : PTR》2008,22(2):185-189
The Gingko biloba extract is contraindicated during pregnancy and lactation due to the lack of information about its effects on these reproductive phases. Previous studies have shown that G. biloba extract contains components with estrogenic and antiestrogenic activities, thus nursing dams treated with the extract of this plant could show reduction in milk production, resulting in malnutrition and poor development of pups. This work analyzes the postnatal development of pups, whose mothers were treated with G. biloba extract during the lactation period. Nursing Wistar rats received 3.5 mg/kg/day of G. biloba aqueous extract, corresponding to the highest human dose. Clinical signs of maternal toxicity were evaluated. The growth rate, viability, survival during treatment and lactation indices of the pups were calculated. The physical, motor and sensorial development of the pups was also evaluated. No maternal signs of toxicity were observed. As there were no biological differences between control and G. biloba treated pups, it is possible to assume that, in this experimental design, the administration of G. biloba aqueous extract to nursing rats during the lactation period seems to be devoid of toxic effect to mothers and to the physical, motor and sensory development of the pups. 相似文献
97.
98.
M. Rut Aguiar Couto Rita Vidal HernándezMontserrat González Rodríguez Antonio López PortelaAlfonso Otero Valenzuela 《Progresos de Obstetricia y Ginecología》2008
Objectives
To evaluate the utility and effectiveness of hysteroscopic retrieval of intrauterine devices (IUDs) in early pregnancy.Subjects and methods
We followed-up four pregnant women with IUDs with retracted tails removed by hysteroscopy before 10 weeks of pregnancy from 2003 to 2005.Results
After hysteroscopy, pregnancy course was successful in three women, without complications that could be attributed to the procedure. There was one abortion due to rupture of fetal membranes at 15 weeks’ gestation.Conclusions
The application of hysteroscopy in pregnancy has always been limited. In all patients, a possible optic nerve lesion in the fetus should be evaluated. This technique should not be performed after the 10th week of pregnancy. In most patients, pregnancy continues without complications after IDU removal. 相似文献99.
100.
Simona Dinicola Alessia Pasqualato Alessandra Cucina Pierpaolo Coluccia Francesca Ferranti Rita Canipari Angela Catizone Sara Proietti Fabrizio D’Anselmi Giulia Ricci Alessandro Palombo Mariano Bizzarri 《European journal of nutrition》2014,53(2):421-431