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A polysaccharide hydrogel was isolated from the seeds of Tamarindus indica (tamarind) and was used as release modifier for the preparation of diclofenac sodium spheroids, using extrusion-spheronization technique. The process was studied for the effect of variables to arrive at spheroids with satisfactory particle shape, size and size-distribution. The prepared spheroids were characterized for surface morphology, qualitative surface porosity, friability, bulk density, and flow properties. The in vitro release studies exhibited a zero-order release kinetics that was confirmed by Higuchi's and Peppas' models. A credible correlation was obtained among swelling index, viscosity, surface roughness of the polysaccharide, and in vitro dissolution profile of the spheroids. In the comparative bioavailability study, we found that the developed spheroids were able to sustain the drug release over 8 hr and could improve the extent of absorption and bioavailability of the drug. 相似文献
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Hazra R Gafni RI Maldarelli F Balis FM Tullio AN DeCarlo E Worrell CJ Steinberg SM Flaherty J Yale K Kearney BP Zeichner SL 《Pediatrics》2005,116(6):e846-e854
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INTRODUCTION: Many patients with schizophrenia are exposed to serious health risks associated with their excess body weight. Evidence exists that even a moderate amount of weight loss may have significant health benefits. Thus, weight control in schizophrenia patients has become an important treatment goal. Although studies in the general population show that satisfaction with body weight is an important predictor for engagement in various weight loss measures, the perspective of schizophrenia patients has not been assessed. METHOD: Information on self-reported weight perception, desire to lose weight as well as weight loss attempts was obtained according to methods employed in the National Health and Nutrition Examination Survey, Cycle III (NHANES III). Body weight and height were measured and body mass index (BMI) was calculated. RESULTS: Perception of body weight and desire to lose weight were correlated to BMI. Both obese female and male subjects (BMI30) were aware of their weight status. However, whereas overweight females (BMI>25< or =29.9) accurately perceived themselves so, males in this category had difficulties perceiving themselves overweight, and consequently neither wanted to lose weight, nor tried to lose weight. As means of weight loss, caloric restriction (diet) was most frequently employed (by more than 80% of study subjects); yet only a third of study subjects (34.4%) engaged in the recommended combination of diet and exercise to lose weight. Questionable weight loss practices were also frequently employed, especially among women. CONCLUSIONS: Obese patients (BMI> or =30) were generally aware of their excess body weight and wanted to lose weight. Only non-obese, yet overweight males (BMI>25< or =29.9) did not perceive themselves as overweight and consequently did not try to lose weight. Weight loss practices did not always follow established recommendations. Especially women were likely to approach weight loss with questionably appropriate and unsafe methods. 相似文献
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INTRODUCTION: Brain phospholipids are uniquely rich in polyunsaturated fatty acids (PUFAs). Most PUFAs such as alpha-linolenic acid 18:3(n-3), eicosapentaenoic acid 20:5(n-3), and docosahexaenoic acid 22:6(n-3) are essential and must be provided through the diet. PUFAs are also very sensitive to oxidative stress. Decreased essential fatty acid content has been observed in cell membranes of various tissue types of schizophrenia patients, including neural cell membranes. A number of mechanisms may account for these deficits, such as inadequate dietary supply or increased oxidation. It is known that patients with schizophrenia make poor dietary choices. However, whether their dietary fatty acid or antioxidant intake is insufficient and contributes to the observed deficiencies has not been assessed. METHODS: After obtaining informed consent, a 24-h diet recall was administered to elicit nutritional information in 146 outpatients with schizophrenia. Intake of fatty acids and antioxidants including vitamins A, C, and E was compared to U.S. population standards according to the National Health and Nutrition Examination Survey Cycle III (NHANES III) results. RESULTS: Saturated and polyunsaturated fatty acid (PUFA) intake was significantly higher in schizophrenia patients than in controls (p相似文献
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BACKGROUND: We have not found any reports on the effect of physiotherapy after knee replacement. PATIENTS AND METHODS: In a prospective randomized controlled trial, we randomized two groups to receive or not receive outpatient physiotherapy following total knee arthroplasty. 120 patients were recruited over 2 years, each followed up for 1 year. Inclusion criteria were age between 55-90 years, less than 40 degrees of fixed flexion contracture and the ability to walk at least 10 meters unaided preoperatively with monoarticular arthrosis. RESULTS: We found no statistically significant benefit of outpatient physiotherapy at any of the three times measured. After adjusting for baseline differences between the two treatment groups, the mean difference in knee flexion 1 year postoperatively was only 2.9 degrees. This mean difference is of no clinical significance. INTERPRETATION: We concluded that in a preselected group of patients following primary total knee arthroplasty, inpatient physiotherapy with good instructions and a well-structured home exercise regime can dispense with the need for outpatient physiotherapy. 相似文献
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Bone plate design has evolved dramatically in recent years. The Dynamic Compression Plate (DCP) has been superseded by bi- and uni-cortical plates that claim a reduced interface contact between the plate and the underlying bone. It is believed that contact reduction ameliorates the localised ischaemia that develops subsequent to plate application. In this study, the interface characteristics of the Limited Contact-Dynamic Compression Plate (LC-DCP) and the Contour Plus (CP) plating systems have been quantitated using Fuji prescale pressure sensitive film interposed between the plate and the bone. Ten-hole plates were applied to the same aspect of either the humeral, radial or ulnar diaphysis of human cadaveric bone in a reproducible manner. The average pressure, force and interface contact area were calculated using Interactive Data Language (IDL) image analysis software. The CP system was consistently lower, in terms of interface contact, than the LC-DCP in each of the specimen locations tested (P<0.0001). The CP system displayed a 'point-contact' configuration along the interface with high pressures recorded at these points, the significance of which is unknown. 相似文献