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101.
102.
Expression and characterization of glutathione peroxidase activity in the human blood fluke Schistosoma mansoni. 总被引:1,自引:0,他引:1 下载免费PDF全文
Antioxidants may play an important role in immune evasion by schistosome parasites. Previous studies have focused on the roles of superoxide dismutase and glutathione S-transferase. In the present study, glutathione peroxidase (GPX) activity was measured in different fractions of worm extracts from several developmental stages of Schistosoma mansoni. The enzyme activity was shown to be developmentally regulated, with higher specific activities being found in the tegument-enriched Nonidet P-40 extract of adult worms (the stage least susceptible to immune killing) than in the larval stages (which are most susceptible to immune elimination). In all extracts tested, the activity against cumene hydroperoxide, even when glutathione S-transferase activity was removed, was higher than that for hydrogen peroxide. The expression of GPX cDNA in pGEX-2T by bacteria produced a 50-kDa fusion protein and a 32-kDa truncated protein. The latter was due to termination at the internal UGA codon that codes for selenocysteine. GPX activity was detected in the recombinantly produced GPX but not with Sj26-glutathione S-transferase from the vector. Mutating the TGA codon to TGT produced a full-length product, GPXm (19 kDa), that was used to produce 19 monoclonal antibodies. Anti-GPXm monoclonal antibodies recognized a 19-kDa molecule in adult-worm extract which, upon removal by immunoprecipitation, resulted in the loss of over 90% of the GPX activity, suggesting that a single form of GPX exists in the schistosome. 相似文献
103.
Summary: On clinical examination of 1232 sheep belonging to the urban and rural areas of Punjab (India) lesions of ringworm could be detected in 22 animals giving an incidence of 1.78%. Animals below the age of 6 months were more frequently affected (7.4%), than those above 6 months (1.03%). Culturally, T. verrucosum, T. mentagrophytes and M. gypseum could be isolated from the skin scrapings of four, two and one sheep respectively.
Zusammenfassung: Bei der klinischen Untersuchung von 1.232 Schafen aus der städtischen und ländlichen Gegend von Punjab (Indien) wurden bei 22 Tieren Veränderungen gefunden, die auf eine Hautmykose verdächtig waren (1,78%). Tiere, die jünger als 6 Monate waren, schienen häufiger befallen zu sein (7,4%) als die älteren Tiere (1,03%). Kulturell konnten T. verrucosum, T. mentagrophytes und M. gypseum aus der Haut von 4, bzw. 2, bzw. 1 Tier isoliert werden. 相似文献
Zusammenfassung: Bei der klinischen Untersuchung von 1.232 Schafen aus der städtischen und ländlichen Gegend von Punjab (Indien) wurden bei 22 Tieren Veränderungen gefunden, die auf eine Hautmykose verdächtig waren (1,78%). Tiere, die jünger als 6 Monate waren, schienen häufiger befallen zu sein (7,4%) als die älteren Tiere (1,03%). Kulturell konnten T. verrucosum, T. mentagrophytes und M. gypseum aus der Haut von 4, bzw. 2, bzw. 1 Tier isoliert werden. 相似文献
104.
105.
B Zakhireh M L Thakur H L Malech M S Cohen A Gottschalk R K Root 《Journal of nuclear medicine》1979,20(7):741-747
Human polymorphonuclear leukocytes (PMNs) were labeled with indium-111 oxine in ethanol, and the effects of the labeling procedure, radioactivity, and concentrations of oxine and ethanol on PMN function and structure were studied in vitro. The standard labeling procedure did not alter the viability, random migration, chemotaxis, bactericidal capacity, or the ultrastructure of PMNs. Exposure to higher doses of radioactivity, or to higher concentrations of ethanol, had no appreciable effects on random migration and chemotaxis of PMNs. A dose-dependent reduction in their random migration and chemotaxis was observed when higher concentrations of oxine were used. These results indicate that In-111-labeled PMNs are structurally intact and have normal in vitro locomotion and bactericidal activity. Indium-111-labeled PMNs should be suitable for studying the kinetics and distribution of these cells in health and disease. 相似文献
106.
Five cases of xeroderma pigmentosum have been presented, three of the patients belonging to one family. There was no history of consanguineous marriages in this series. All five patients had advanced ocular complications. Three presented with multiple basal cell carcinomata, which were treated by radiotherapy in two cases and surgery in one. One patient presented with a dermatofibroma, which does not seem to have been reported earlier in association with this disease. Reconstructive techniques such as the use of flaps and grafts arc safe, and the healing response is quite satisfactory. 相似文献
107.
OBJECTIVE: To estimate the effectiveness of Bacillus Calmette Guerin (BCG) vaccination in the prevention of leprosy. Study design. Population-based case-control study. METHODS: The study was carried out in Yavatmal District, Maharashtra, India. It included 364 cases of leprosy (diagnosed by the World Health Organization's criteria), born since 1962, that were detected during a leprosy survey conducted by the Government of Maharashtra in 2,175,514 people. Each case was pair-matched with one neighbourhood control for age, sex and socio-economic status. Exclusion criteria for controls included past or current history of tuberculosis or leprosy. BCG vaccination status was assessed by examination for the presence of a BCG scar, immunization records if available and information from subjects/parents of children. Subjects who were uncertain about BCG vaccination were not included. RESULTS: A significant protective association between BCG and leprosy was observed [odds ratio=0.46, 95% confidence intervals (CI) 0.34-0.61]. Overall vaccine effectiveness (VE) was 54% (95% CI 39-66). BCG effectiveness against multibacillary, paucibacillary and single skin lesion leprosy was 68% (95% CI 26-86), 57% (95% CI 29-74) and 48% (95% CI 22-65), respectively. Analysis of linear trend revealed a significant linear association between the protective effect of BCG and the type of leprosy. The BCG vaccine was more effective in those aged < or =20 years compared with those aged >20 years (VE 61%, 95% CI), among females compared with males (VE 60%, 95% CI), in lower socio-economic strata compared with upper and middle strata (VE 57%, 95% CI), and in subjects who had a BCG scar size < or =5 mm compared with those with a BCG scar size >5 mm (VE 61%, 95% CI). However, these differences were not statistically significant, as reflected by the overlapping 95% CIs. The overall prevented fraction was 35% (95% CI 22-46). CONCLUSION: The current study identified a beneficial role of BCG vaccination in the prevention of leprosy in the study population. 相似文献
108.
Biswas PN Thakur SK Mukherjee H Bhaduri G 《Journal of the Indian Medical Association》2005,103(10):539, 542
Ophthalmomyiasis is a rare condition. Here two such patients, one of 70-year-old male farmer with history of neglected trauma presented with painful swelling with sinus of right orbit and the second one of 65-year-old female destitute who presented with fungating mass near the medial canthus of left eye with pain and bleeding are reported. All the maggots were removed after applying ether. 相似文献
109.
110.
Serum copper and zinc concentrations and their relation to superoxide dismutase in severe malnutrition 总被引:1,自引:0,他引:1
Serum Zn and Cu levels were measured by atomic absorption spectrophotometry in 117 children (aged 3 months to 5 years), divided into two groups; 80 children suffered from severe malnutrition and 37 children served as controls. Significantly lower levels of serum Zn and Cu were found in the malnutrition group. Zn levels of 2.59±0.15 µg/ml as compared to 3.92±0.35 µg/ml in the control group (P=0.0037) and Cu levels of 0.74±0.05 µg/ml in the malnutrition group as compared to 1.19±0.08 µg/ml in the control group were observed. Superoxide dismutase activity in children with severe malnutrition was 21.13±0.75 U/min per mg protein as compared to 26.02±0.66 U/min per mg protein in controls. Absence of breast-feeding, recurrent respiratory tract infection and diarrhoea correlated significantly with low serum Zn and Cu levels. Hypoproteinaemia and anaemia in malnourished children were also associated with a significant decline in both serum Zn and Cu levels. Conclusion:Serum trace element deficiency leading to depleted antioxidant protection may be a contributing factor to the pathophysiology of protein malnutrition and replacement of these elements in the management of this condition might be important. 相似文献