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Modification of various properties of graphene oxide (GO) films on SiO2/Si substrate under KrF laser radiation was extensively studied. X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy and the electrical resistance measurements were employed to correlate the effects of laser irradiation on structural, chemical and electrical properties of GO films under different laser fluences. Raman spectroscopy shows reduced graphene oxide patterns with increased I2D/IG ratios in irradiated samples. X-ray photoelectron spectroscopy shows a high ratio of carbon to oxygen atoms in the reduced graphene oxide (rGO) films compared to the pristine GO films. X-ray diffraction patterns display a significant drop in the diffraction peak intensity after laser irradiation. Finally, the electrical resistance of irradiated GO films reduced by about four orders of magnitudes compared to the unirradiated GO films. Simultaneously, reduction and patterning of GO films display promising fabrication technique that can be useful for many graphene-based devices.

Modification of various properties of graphene oxide (GO) films on SiO2/Si substrate under KrF laser radiation was extensively studied.  相似文献   
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Karam  Mohamad  Ghanem  Ismat  Vergari  Claudio  Khalil  Nour  Saadé  Maria  Chaaya  Céline  Rteil  Ali  Ayoub  Elma  Saad  Eddy  Kharrat  Khalil  Skalli  Wafa  Assi  Ayman 《European spine journal》2022,31(9):2326-2338
European Spine Journal - To evaluate the global alignment of non-operated subjects with adolescent idiopathic scoliosis. A total of 254 subjects with AIS and 64 controls underwent low dose biplanar...  相似文献   
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Karam  Mohammad  Bizdikian  Aren Joe  Khalil  Nour  Bakouny  Ziad  Obeid  Ibrahim  Ghanimeh  Joe  Labaki  Chris  Mjaess  Georges  Karam  Aya  Skalli  Wafa  Kharrat  Khalil  Ghanem  Ismat  Assi  Ayman 《European spine journal》2020,29(8):2010-2017
European Spine Journal - To evaluate the 3D deformity of the acetabula and lower limbs in subjects with adolescent idiopathic scoliosis (AIS) and their relationship with spino-pelvic alignment. Two...  相似文献   
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BACKGROUND: The advent of double switch procedures for the treatment of transposition of the great arteries with L-looped ventricles, e.g. typical congenitally corrected transposition of the great arteries, has made delineation of the coronary artery anatomy in these hearts important. Previous studies have suggested a consistently inverted coronary arterial pattern. METHODS: A morphologic study was conducted of the coronary arterial anatomy of all heart specimens in our registry of approximately 2600 hearts with segmental anatomy [S,L,L] (situs solitus of the viscera and atria, ventricular L-loop, and levoposition of the aorta), with anatomical features to permit such repair. RESULTS: Twenty specimens collected between 1965 and 1993 ranged in age from 1 day to 23 years. Transposition of the great arteries or double outlet right ventricle was seen in 12 (60%). One had a single coronary artery that arose from the right anterior sinus and trifurcated. Another had the anterior descending artery arise from the right ventricular coronary artery while the circumflex arose alone, directly above the intercoronary commissure. Eccentric ostia were seen in another four, with one left ventricular coronary artery originating directly above the intercoronary commissure. Right ventricular aorta with pulmonary atresia was in eight of the total (40%). Three had eccentric ostia: one with both arteries from the left posterior sinus, and one with the left ventricular coronary over the intercoronary commissure. None of these specimens had additional coronary anomalies that would further complicate surgery. CONCLUSION: Nearly half of the specimens (45%) had coronary artery abnormalities that could have complicated, but not necessarily precluded, anatomic surgical repair.  相似文献   
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The objective of this study was to assess the course, the epidemiologic features and the prognosis of recurrent Legg-Calvé-Perthes disease. We reviewed seven reported cases and one personal case of recurrent Perthes' disease. In all cases, complete recovery from the previous episode was documented, and a thorough diagnostic work-up to rule out other diseases was undertaken. There were five boys. Age at onset ranged from 2 to 6 years. Five patients had bilateral involvement. Recurrence took place 1-5 years after complete healing of the initial one. Clinical and radiological pictures were similar to those found in primary Perthes' disease of the adolescent and consisted in a greater epiphyseal involvement. Recurrent Perthes' disease is very rare. We did not identify any risk factors for recurrence. A worse outcome is more closely related to an older age of the patient at recurrence than to recurrence itself.  相似文献   
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This cross-sectional study investigated the prevalence of anaemia and vitamin A deficiency (VAD) among pregnant women in a poor urban population of Bangladesh. It also examined the association of various socio-economic and dietary factors with anaemia and vitamin A status. A maternal and child health clinic in Dhaka city, Bangladesh was used to obtain the sample. Three hundred and eighty three pregnant women, aged 20-30 years, of 20-30 weeks gestation were randomly selected from women on their first presentation for antenatal care. Socio-economic, pregnancy related information, usual dietary pattern and anthropometric data were collected. Blood haemoglobin and serum retinol (vitamin A) concentrations were determined. About 40% of the pregnant women were anaemic (haemoglobin <11.0 g/dl) and 45% had low serum vitamin A levels (<30 microg/dl); with 8.6% having sub-clinical VAD (serum retinol <20 microg/dl). The women with low serum vitamin A levels had 1.8 times greater risk of being anaemic than did the women with normal vitamin A status. Food frequency data revealed that a large proportion of these women did not consume egg (49%), milk (25%), meat (31%), liver (83%), large fish (32%), small fish (39%) and sweet pumpkin (52%) at all; while about 25% of the women reported consuming dark green leafy vegetables (DGLV) and 64% reported an intake of fruit at least four servings a week. The pregnant women who were either illiterate or received only informal education (up to grade ten) had significantly lower haemoglobin and serum vitamin A levels compared to those who completed at least a secondary school certificate. The women whose husbands were illiterate or received only informal education had significantly (P= 0.01) lower serum vitamin A levels than those whose husbands had received at least a secondary school certificate. The women who came from families with a per-capita income below the poverty line had significantly lower haemoglobin and serum vitamin A levels compared to those who came from families with a per-capita income above the poverty line. The women who consumed three servings or less of DGLV and fruit per week had significantly lower haemoglobin and serum vitamin A levels than those who consumed four or more servings a week. The women who never consumed large fish had significantly lower haemoglobin compared to those who reported at least one serving a week. Furthermore, the women who never consumed sweet pumpkin had significantly lower serum vitamin A than the women who ate at least one serving a week. By multiple regression analysis, intake of meat, DGLV and fruit, and serum vitamin A levels were found to have a significant independent relationship with haemoglobin. The overall F-ratio (9.9) was highly significant (P=0.000), the adjusted R-square was 0.086 (multiple R=0.309). Multiple regression analysis for serum vitamin A also revealed a significant independent relationship with per capita income, haemoglobin levels, intakes of DGLV and sweet pumpkin. The overall F-ratio (10.2) was highly significant (P=0.000), the adjusted R-square was 0.10 (multiple R=0.312). In conclusion, anaemia and vitamin A deficiency were highly prevalent among poor urban pregnant women in Bangladesh. Various socio-economic and dietary factors may influence the anaemia and vitamin A status of these women. The present study emphasizes the need for a comprehensive intervention strategy, which include both nutritional and environmental factors, to improve the nutritional status of this population.  相似文献   
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