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Concentration and metabolic replacement (turnover) rate of glucose and ketone bodies were determined at intervals during a 52 day postweaning fast in five grey seal (Halichoerus grypus) pups, using bolus injections of radiotracers. Blood glucose was maintained at a high level throughout the fast, while beta-hydroxybutyrate increased 26 times from day 3 to day 37, whereafter it by and large was maintained. Glucose replacement rate decreased to 56% of the day 9 value at day 37 and dropped further to only 32% of the day 9 level at day 52 in two seals, while in another 2 seals it increased at this late stage. The average ketone body replacement rate ranged between 8.6 and 13.8 mumols min-1 kg-1, but did not change significantly (P greater than 0.05) during the fasting period. These results suggest a reduced gluconeogenesis from protein and increased production of ketone bodies, which may in part replace glucose as energy source during fasting. 相似文献
3.
Body temperature, blubber thickness and lung capacity (Vc) were recorded in newly killed minke whales, while respiratory frequency (f) was determined in free-swimming animals. Mean deep (thoracic) body temperature was 34.7 +/- 0.8 (SD) degrees C (n = 14). Weighted mean core/blubber interface temperature in animals caught in 2.5-5.5 degrees C water was 28.8 +/- 1.7 degrees C (n = 8). The minimum average rate of sensible heat loss (HLs) was 3.81 +/- 0.53 (SD) W kgw-0.75 (n = 8) in animals with body masses (w) in the range of 1840 to 5740 kg, HLs being inversely proportional to w (HLs = -2.98 10(-4) w +4.89 W kgw-0.75 (n = 8, r2 = 0.73, P less than 0.01)). The average rate of respiratory heat loss (HLr) was 0.26 +/- 0.04 (SD) W kgw-0.75, regardless of w, in the same 8 animals. Total rates of heat loss (HL = HLr+HLs) in 2.5-5.5 degrees C water ranged between 3.40 and 4.87 W kgw-0.75, with an average of 4.06 +/- 0.52 (SD) W kgw-0.75 (n = 8). Estimates of oxygen consumption based on records of f and Ve, and data on oxygen extraction from other cetaceans, yielded a range of metabolic rates which compared nicely with the calculated HL values. 相似文献
4.
Familial hyperinsulinemia due to a structurally abnormal insulin. Definition of an emerging new clinical syndrome 总被引:7,自引:0,他引:7
M Haneda K S Polonsky R M Bergenstal J B Jaspan S E Shoelson P M Blix S J Chan S C Kwok W B Wishner A Zeidler 《The New England journal of medicine》1984,310(20):1288-1294
We have identified a patient with mild diabetes, marked fasting hyperinsulinemia (89 to 130 microU of insulin per milliliter), and a reduced fasting C-peptide: insulin molar ratio of 1.11 to 1.50 (normal, greater than 4). The patient responded normally to exogenous insulin. However, her endogenous immunoreactive insulin showed reduced biologic activity during a glucose-clamp study with hyperglycemia and a reduced ability to bind to the insulin receptor and stimulate glucose transport in vitro. Family studies showed that five additional relatives in three generations had variable degrees of glucose intolerance, marked hyperinsulinemia, and a reduced peripheral C-peptide:insulin molar ratio. Restriction-endonuclease cleavage of DNA isolated from circulating leukocytes in the patient and in family members with hyperinsulinemia revealed loss of the MboII recognition site in one allele of the insulin gene--consistent with a point mutation at position 24 or 25 in the insulin B chain. Other studies using high-pressure liquid chromatography and detailed gene analysis have identified the defect as a serine for phenylalanine substitution at position 24 of the insulin B chain. The secretion of a structurally abnormal insulin should be considered in patients with hyperinsulinemia who respond normally to exogenous insulin and have a reduced C-peptide:insulin molar ratio. Glucose tolerance may range from relatively normal to overtly diabetic. 相似文献
5.
D Coleman-Wallace J W Lee S Montgomery G Blix D T Wang 《The Journal of school health》1999,69(8):314-319
Despite introduction of numerous smoking prevention programs in schools, tobacco use has not declined among adolescents. Schools face the dilemma of what to do with students who smoke and are not ready to quit. This study evaluated two programs based on the stages of change model. The educational program, the Tobacco Education Group (TEG), was designed for adolescents not yet thinking about quitting. The cessation program, the Tobacco Awareness Program (TAP), was intended for adolescents who want to quit. Evaluation was completed on 351 students at six public high schools. Compared to a control group of adolescent smokers not assigned to programs, both intervention groups significantly decreased tobacco use. Self-reported use was validated biochemically. Self-efficacy for quitting increased in both programs. Posttest use was predicted by posttest self-efficacy, peer support, and parental support, after controlling for initial use and initial self-efficacy. 相似文献
6.
Kristine Blix Sigrid K. Brækkan Saskia le Cessie Finn E. Skjeldestad Suzanne C. Cannegieter John-Bjarne Hansen 《European journal of epidemiology》2014,29(4):277-284
Whether the high incidence of venous thromboembolism (VTE) in the elderly can be attributed to cancer is not well studied. We assessed the impact of cancer on risk of VTE in young, middle-aged and elderly. 26,094 subjects without a history of cancer or VTE were recruited from the Tromsø study. Incident cancer (n = 2,290) and VTE (n = 531) were recorded from baseline (1994–1995) through December 31st, 2009. Cox regression with cancer as time-varying exposure was used to calculate hazard ratios with 95 % confidence intervals (CI). Overt cancer was associated with a fivefold (95 %CI 4.3, 6.7) increased risk of VTE, with an age-dependent gradient from 26-fold (95 %CI 12.1, 56.5) increased in the young, ninefold (95 % CI 6.6, 12.7) increased in the middle-aged, and threefold (95 % CI 2.5, 4.5) increased risk in the elderly. The population attributable risks were 14, 27 and 18 %, respectively. Conclusion: The relative risk of VTE by cancer were higher in young compared to elderly subjects, but the proportion of VTEs in the population due to cancer did not differ much across age groups. Our findings indicate that the increased risk of VTE by advancing age cannot be attributed to higher incidence of cancer in the elderly. 相似文献
7.
R A Jackson P M Blix J A Matthews L M Morgan A H Rubenstein J D Nabarro 《Metabolism: clinical and experimental》1983,32(7):706-710
Forearm glucose uptake (FGU) and other metabolic responses were studied in six normal men for three hours after a 75-g oral glucose load and a mixed meal containing 75 g carbohydrate. After the meal the rise in arterial glucose levels was considerably less than that following the oral glucose load but the overall insulin responses from 0 to 180 minutes were not statistically different. Although the initial rise in FGU was more gradual after the meal, the subsequent elevation was more sustained and, at the termination of the study, exceeded significantly that seen after the oral glucose load. The rise in GIP levels during the first hour was similar after the meal and the oral glucose load, but thereafter concentrations following the oral glucose load fell while those after the meal continued to rise. When the incremental area (delta) is used as the index of response, the results show that while the glucose response (delta G) after the meal (19.1 +/- 5.3 units) was only 26% of that after oral glucose loading (72.7 +/- 7.0 units), the corresponding increase in FGU (delta FGU) reached 62% (55.0 +/- 12.8 units after the meal, 89.2 +/- 20.0 units after the oral glucose load). Thus, the increase in peripheral glucose uptake relative to the glycemic response (delta FGU/delta G) was significantly greater after the meal than following the oral glucose load alone (P less than 0.05). In conclusion, relative to the rise in arterial glucose levels, peripheral glucose uptake is greater after a meal than after glucose loading with an equivalent carbohydrate challenge. Furthermore, the present data support previous studies emphasizing the failure of GIP alone to explain the entero insular axis. 相似文献
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9.
TRA Lane HM Moore IJ Franklin AH Davies 《Annals of the Royal College of Surgeons of England》2015,97(2):e18-e20
The endovenous revolution has accelerated the development of new techniques and devices for the treatment of varicose veins. The ClariVein® mechanochemical ablation device offers tumescentless treatment with a rotating ablation tip that can theoretically become stuck in tissue. We present the first report of retrograde stripping of the small saphenous vein without anaesthesia following attempted use of the ClariVein® device, without adverse sequelae. 相似文献
10.
PAG Torrie A Leonidou IJ Harding G Wynne Jones MJ Hutchinson IW Nelson 《Annals of the Royal College of Surgeons of England》2013,95(8):604-608