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排序方式: 共有1809条查询结果,搜索用时 15 毫秒
1.
Ligia Teban Hubert Pehamberger Klaus Wolff Michael Binder Harald Kittler 《Journal der Deutschen Dermatologischen Gesellschaft》2003,1(4):292-296
Background and objectives: The aim of this study was to evaluate the practical value of the dermatoscopic classification of Clark nevi Patients and methods: Dermatoscopic images of 268 lesions clinically and dermatoscopically diagnosed as Clark nevi were presented to 2 dermatologists without knowledge of the histological diagnosis. The dermatologists evaluated the lesions according to a simplified version of the classification scheme for Clark nevi proposed by Hofmann‐Wellenhof and differentiated between 12 different types of Clark nevi. Results: The most common type of Clark nevus was the reticular‐homogenous type (n = 64, 23,9 %), followed by the globular‐homogeneous type (n = 32, 12 %) and by the homogenous type (n = 30, 11,2 %). The overall inter‐rater agreement between the examiners was moderate to good (kappa = 0,58). The highest level of agreement was found for the peripheral hyperpigmented type (kappa = 0,83). Histologically, 17 lesions (6,3 %) were diagnosed as melanomas. The frequency of melanoma was highest among the peripheral‐hyperpigmented type for one observer and among the homogenous type for the other observer. No melanoma was found among the globular, reticular‐globular, and the central‐hyperpigmented types. Conclusions: A dermatoscopic classification of Clark nevi is practically feasible and allows – to some extent – a risk stratification of Clark nevi, which could be useful for clinical management. 相似文献
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3.
V Dietz M Lezana C Garcia Sancho R Montesano 《International journal of epidemiology》1992,21(4):800-806
In 1985, the Pan American Health Organization adopted the goal of eradication of poliomyelitis from the Americas by 1990. Strategies to accomplish this included high vaccination coverage, aggressive outbreak control, and active surveillance for acute flaccid paralysis (AFP). Although the sensitivity of AFP surveillance for detecting paralytic poliomyelitis cases is high, studies have shown the specificity to be low. In 1990, 2497 notified cases of AFP were investigated in the Americas of which 2146 had stool specimens collected. However, only 18 were confirmed as poliomyelitis by isolation of wild poliovirus from stool specimens, 71 were classified as being compatible with poliomyelitis. Cases of AFP due to causes other than poliomyelitis result in extensive but unnecessary outbreak control measures. To predict, at initial clinical evaluation, the likelihood of future confirmation as a case of poliomyelitis, likelihood ratios (LR) were calculated for different combinations of clinical characteristics of AFP cases (249) from Mexico in 1989 and 1990. The best predictors in a child with AFP were proximal muscle involvement which progressed '4 days together with fever at onset of paralysis, and proximal and unilateral involvement with either fever at onset or paralysis which progressed '4 days. The odds would increase by 12 that the child would eventually be confirmed as poliomyelitis (19), based on a stool culture positive for wild poliovirus (95% confidence interval (CI) 2.6-55.9). A guide for use in the field is proposed whereby local health officials, often with little training in neurological evaluation, can predict at initial clinical examination the likelihood that an AFP case will subsequently be confirmed as poliomyelitis.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
J Suárez de Lezo A Medina M Pan E Hernández M Sancho A Bethencourt M Romero F Melián J Segura F Jiménez 《Revista espa?ola de cardiología》1991,44(2):106-114
We study 40 patients, 55 +/- 7 years old with acute myocardial infarction treated early by thrombolytic therapy (20 STK and 20 rt-PA). All patients were angiographically studied in the following conditions: 1) baseline, before initiating therapy. 2) Three hours after treatment. 3) Twenty four hours later. 4) Before discharge. The infarct related artery was patent 24 hours after treatment in 31 patients (78%); five of them were patent before treatment, and we observed an early reperfusion in 20 patients (57%) and late reperfusion in 6 patients (17%). The number of patients with angiographic evidence of intraluminal thrombus decreased progressively through conditions while the grade TIMI of coronary perfusion increased in the absence of reocclusion. Final regional wall motion of infarct related myocardial zones and their degree of recovery were significantly higher in recanalized patients, as compared with non-reperfused patients. Similarly, left ventricular functional recovery was higher in patients with antegrade of collateral flow to the infarct area, as compared with totally occluded patients. 相似文献
5.
Juana M. Sancho 《Journal of muscle research and cell motility》1991,12(1):71-119
Abstracts of the XIX European Conference on Muscle contraction and Cell Motility 相似文献
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7.
Georges Dellatolas Lucia Willadino Braga Ligia do Nascimento Souza Gilberto Nunes Filho Elizabeth Queiroz Gerard Deloche 《Journal of the International Neuropsychological Society》2003,9(5):771-782
The effect of the degree of illiteracy (complete or incomplete) on phonological skills, verbal and visual memory and visuospatial skills is examined in 97 normal Brazilian adults who considered themselves illiterate, and 41 Brazilian school children aged 7 to 8 years, either nonreaders or beginning readers. Similar literacy effects were observed in children and in adults. Tasks involving phonological awareness and visual recognition memory of nonsense figures distinguish the best nonreaders and beginning readers. Children performed better than adults at oral repetition of short items and figure recall, and adults better than children at semantic verbal fluency, digit span, and word list recall. A principal component analysis of the correlations between tasks showed that phonological awareness/reading, phonological memory/oral repetition, and semantic verbal memory/fluency tasks, generated different components. The respective role of culturally based preschool activities and literacy on the cognitive functions that are explored in this study is discussed. 相似文献
8.
A. Alonso P. Martin C. Albarran M. Sancho 《International journal of legal medicine》1993,105(6):311-314
Summary The polymorphism of the D1S80 locus has been analyzed in a population sample of 203 unrelated individuals living in Madrid (central Spain) by PCR and subsequent semi-dry discontinuous polyacrylamide gel electrophoresis (Tris-chloride/Tris-glycine buffer system) followed by silver staining, The electrophoretic system described in this study offers high resolution in the separation of the different D1S80 alleles allowing the detection of microvariability around the allele T22 in the spanish population. Twenty different alleles containing 17–40 repeats of the basic 16bp unit were distinguished. The alleles T18 and T24 were found to be relatively common in Spain, as in other populations:, with frequencies of 0.224 and 0.372, respectively. No evidence of significant deviations from Hardy-Weinberg equilibrium was found in these preliminary population data. 相似文献
9.
Redefining the significance of aneuploidy in the prognostic assessment of colorectal cancer 总被引:5,自引:0,他引:5
Risques RA Moreno V Marcuello E Petriz J Cancelas JA Sancho FJ Torregrosa A Capella G Peinado MA 《Laboratory investigation; a journal of technical methods and pathology》2001,81(3):307-315
The aberrant content of DNA, or aneuploidy, is a hallmark of tumor cells and may be associated with malignant potential. Based on the hypothesis that aneuploidy, as a form of genetic instability, results in an increased capability to generate cell heterogeneity, we investigated whether a comprehensive assessment of aneuploidy extent and degree might be a reliable indicator of tumor aggressiveness. DNA content was determined by flow cytometry in the infiltrating front of 131 paraffin-embedded primary colorectal carcinomas collected in a prospective design. Enrichment of tumor cells by sample microdissection resulted in neoplastic cell contents above 75%. An estimate of aneuploidy, the aneuploidy index (AI), was calculated as the tumor DNA content adjusted by the percentage of diploid and aneuploid cells in G0/G1. Thirty-nine tumors were diploid, 90 hyperdiploid, and 2 hypodiploid. The mean AI in aneuploid tumors was 1.20+/-0.17 and correlated with Dukes' stage and metastasis (p < 0.05). A high AI (receiver operating characteristic curve cutoff value greater than 1.14) predicted a poorer outcome in univariate (p = 0.004) and multivariate (p = 0.01) analyses. Based on these results, we postulate that aneuploidy is the molecular engine of progression in a subset of colorectal cancers, in which the AI seems to be a sensible and independent gauge of malignant potential. The AI determination may have prognostic application in colorectal cancer, especially in low-grade tumors, which might benefit from coadjuvant therapies. 相似文献
10.
Tomas Ojeda Deodato Radic Ligia Gargallo Daphne Boys 《Macromolecular chemistry and physics.》1980,181(11):2237-2244
Poly[4-(1,1,3,3-tetramethylbutyl)phenyl methacrylate] ( 1a ) was synthesized and its physicochemical properties were determined in the condensed phase and in dilute solution. The polymerization of 4-(1,1,3,3-tetramethylbutyl)phenyl methacrylate was carried out by radical mechanism in solution with 2,2′-azoisobutyronitrile as initiator. Several samples were characterized by their intrinsic viscosity, by osmometric measurements, differential scanning calorimetry, and X-ray diffraction. The viscometric behaviour of fractions of 1a was studied in good solvents and theta solvents, and the conformational parameters were calculated. Polymer 1a presents an unusual high rigidity in the chain. X-Ray diffraction of this polymer indicates a one-dimensional ordering of a mesomorphic type. 相似文献