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We present a simple method for preparing an ear wick for treating otitis externa in ENT outpatient clinics. In our experience, this method is efficient, economical and clean, and ensures an equal distribution of the medication along the wick. 相似文献
63.
Hisham A. Essawy Ahmed S. Badran Ahmed M. Youssef Abou El‐Fettouh A. Abd El‐Hakim 《Macromolecular chemistry and physics.》2004,205(17):2366-2370
Summary: Na‐montmorillonite (MMT) with a cation exchange capacity (CEC) of 90 meq/100 g was converted to MMT‐CTAB and MMT‐CPC by the intercalation of cetyltrimethylammonium bromide (CTAB) and cetylpyridinium chloride (CPC), respectively. The intercalation of CPC onto the basal space of the montmorillonite expanded the basal space from 12.19 to 21.47 Å, whereas in the case of CTAB, the spacing was only expanded to 19.35 Å. The MMT‐CPC and MMT‐CTAB forms were subsequently used as hosts for the preparation of polystyrene nanocomposites via intercalative free‐radical polymerization of styrene. Different structures were obtained by varying the preparation conditions; the exfoliated and intercalated nanocomposites were characterized by X‐ray diffraction (XRD), transmission electron microscopy (TEM), thermal gravimetric analysis (TGA), and differential scanning calorimeter (DSC). The produced nanocomposites exhibited improved thermal stability in comparison with that of pure polystyrene above 400 °C especially in the case of the nanocomposites based on the MMT‐CPC, in which intercalation exists. A glass transition temperature (Tg) could not be detected for the prepared nanocomposites using DSC; this was assumed to result from the restricted molecular motion of the polymer chains.
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Annette?AM?GerritsenEmail author Inge?Bramsen Walter?Devillé Loes?HM?van Willigen Johannes?E?Hovens Henk?M?van der Ploeg 《BMC public health》2004,4(1):7
Background
This article discusses the design of a study on the prevalence of health problems (both physical and mental) and the utilisation of health care services among asylum seekers and refugees in the Netherlands, including factors that may be related to their health and their utilisation of these services. 相似文献66.
Kalach N Badran AM Jaffray P Campeotto F Benhamou PH Dupont C 《The Turkish journal of pediatrics》2003,45(1):6-10
The purpose of our study was to systematically evaluate gastric acid output in children with long-lasting gastro-esophageal reflux (GER) in order to assess its mechanism and the need for anti-acid treatment. The investigation was carried out in 20 males and 10 females, aged 7.5 +/- 3.8 years, with prolonged (>15 months) clinical manifestations of GER. All underwent routine ambulatory 24-h esophageal pH-monitoring and measurement of gastric acid secretion including gastric basal (BAO) (micromol/kg/h), maximal (MAO) and peak acid outputs (PAO) after pentagastrin (6 microg/kg sec) stimulation. Children with heartburn or abdominal pain underwent upper fiber-endoscopy. In group A (moderate GER, n=12), patients had a normal reflux index (pH<4 below 5.2% of total recording time) despite abnormal Euler and Byrne scoring (median 57, 95% confidence interval 53.5-73.4). In group B (severe GER, n=18, among whom 5 were with grade III esophagitis), reflux index was >5.2%. When considering all children, esophageal pH (%) was significantly correlated with MAO and PAO, r=0.33, p=0.05 and r=0.37, p=0.04, respectively. Children of group B exhibited significantly higher BAO (75, 53.96-137.81), MAO (468, 394.1-671.3) and PAO (617, 518.8-782.3) than those of group A, BAO (27, 10.8-38.5), MAO (266, 243.2-348.2) and PAO (387, 322.5-452.7), p<0.05). The five children of group B with severe esophagitis exhibited significantly higher BAO, MAO and PAO than the other 13 children from the same group and those of group A, p<0.05. Children with long-lasting and severe GER hyper-secrete gastric acid. Individual variations in gastric acid secretion probably account for variations in gastric acid inhibitor requirements. Anti-secretory treatment is justified in children with long-lasting GER and high pH-metric reflux index. 相似文献
67.
Central venous access is important in both assessment and treatment of the patient. In modern clinical practice, a percutaneous approach is preferred. The well-established subclavian and internal jugular vein catheterization techniques, however, still carry the risk of major acute complications. In this article we describe a trial study of a percutaneous brachiocephalic vein catheterization technique conducted on a total of 74 cadavers undergoing autopsy. Relying on constant and easily recognizable anatomical landmarks, we performed a total of 128 catheterizations of the right and left brachiocephalic veins. The success of catheterization was ascertained by regional dissection. Our results show very high reproducibility with a success rate of about 97% on the first attempt of catheterization on both right and left sides. Equally important, collateral injury of neighboring structures was consistently absent. We propose the introduction of this rather overlooked approach into clinical practice. 相似文献
68.
Several fused triazolo and ditriazoloquinoxaline derivatives such as 1-aryl-4-chloro-[1,2,4]triazolo[4,3-a]quinoxalines (3a-d), 4-alkoxy[1,2,4]triazolo[4,3-a]quinoxalines (4a,b), 4-substituted-amino-[1,2,4] triazolo[4,3-a]quinoxalines (5a-h), 1-(aryl)-[1,2,4]triazolo[4,3-a]quinoxalin-4(5H)-thione (6), 4-(arylidenehydrazino)1-phenyl-[1,2,4]triazolo[4,3-a]quinoxalines (10a-e) and [1,2,4]ditriazolo[4,3-a:3',4'-c]quinoxaline derivatives (11-13) have been synthesized and some of these derivatives were evaluated for antimicrobial and antifungal activity in vitro. It was found that compounds 3a and 9b possess potent antibacterial activity compared to the standard tetracycline. 相似文献
69.
Background: The RNA genome of hepatitis C virus (HCV) displays extensive sequence variation. In this study, serotyping and genotyping
techniques were applied to assess this variability by comparing the performance of the serotyping assay with a panel of well-characterized
HCV strains isolated from chronic active hepatitis (CAH) patients.
Patients and Methods: 60 serum samples from CAH patients were analyzed. All isolates were genotyped by a line probe assay and the results of genotyping
and serotyping were evaluated.
Results: The overall sensitivity of the serotyping and genotyping techniques was 81.16% with a concordance of 73.3%. Type 4 was detected
in 73.3% of cases and it was highly heterogeneous.
Conclusion: Type 4 HCV is the most prevalent type in Egyptian CAH patients and there is a high concordance between the results of serotyping
and genotyping techniques.
Received: January 18, 2000 · Revision accepted: December 3, 2000 相似文献
70.