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991.
992.
Antonín Vězda 《Folia Geobotanica》1967,2(4):383-396
Eine taxonomische Studie über die GattungSagiolechia Massal. als wieter Teil einer Revision der FamilieGyalectaceae sensuZahlbruckner wird vorgelegt. 相似文献
993.
994.
995.
In order to ascertain the prevalence of chronic respiratory disease in residents of a rural town and to determine the relative importance of tobacco smoking and air pollution, a survey was conducted of 726 persons living at Chilliwack, British Columbia, in May and June, 1963. Over 95% of a random sample of adults was interviewed and performed simple tests of respiratory function. The sample was selected from a commercial census. An analysis of the demographic characteristics of the sample indicated that the group, aged 25 to 74 years, was reasonably representative for detailed study of chronic respiratory disease. 相似文献
996.
997.
998.
Production of mosquito larvicidal Bacillus thuringiensis serotype H-14 on raw material media from Nigeria 总被引:2,自引:1,他引:1
Bacillus thuringiensis serotype H-14 de Barjac, a potent larvicide of many mosquito and blackfly species, was grown on various media compounded from fermented cassava ( Mannihot esculenta ), ground and whole maize ( Zea mays ) grains and whole cowpeas ( Vigna unguiculata ) in shake flask fermentations. The liquors obtained from 100g/l of the whole cowpea and maize grains as well as combinations of these were used for further fermentations in 1 and 5 1 fermenters. The final whole cultures obtained were bioassayed against L11/111 of Aedes aegypti and the concentration-effects estimated. The potency of the preparations (estimated as LC50 , strength that showed 50% mortality of the mosquito larvae) ranged from 10.5 mg/l for the 1:3 combination of cowpea steep liquor:maize steep liquor to 90 mg/l for the 2:1 combination at 95% confidence limits. The LC50 of a standard nutrient broth-yeast extract medium was 18 mg/l. The juice of Citrus aurantifolia and an extract from Elaeis guiniensis were used as acid and alkali respectively while bleached deodorized palm olein was used as antifoam. 相似文献
999.
Cold and hyperosmolar fluids in canine trachea: vascular and smooth muscle tone and albumin flux 总被引:5,自引:0,他引:5
Deffebach M. E.; Salonen R. O.; Webber S. E.; Widdicombe J. G. 《Journal of applied physiology》1989,66(3):1309-1315
We have studied the effects of liquids of various osmolalities and temperatures on the tracheal vasculature, smooth muscle tone, and transepithelial albumin flux. In 10 anesthetized dogs a 10- to 13-cm length of cervical trachea was cannulated to allow instillation of fluids into its lumen. The cranial tracheal arteries were perfused at constant flow, with monitoring of the perfusion pressures (Ptr) and the external tracheal diameter (Dtr). Control fluid was Krebs-Henseleit solution (KH) with NaCl added to result in a 325-mosM solution (isotonic). Hypertonic solutions were KH with NaCl (warm hypertonic) or glucose (hypertonic glucose) added to result in a 800-mosM solution. All solutions were at 38 degrees C, with isotonic and the hypertonic NaCl solutions also given at 18 degrees C (cold isotonic and cold hypertonic). Fluorescent labeled albumin was given intravenously, and the change in fluorescence in the fluid was measured during each 15-min period. Changing from warm isotonic to cold isotonic decreased Dtr and Ptr. Changing from warm isotonic to warm hypertonic or hypertonic glucose decreased Ptr with no change in Dtr. The cold hypertonic responses were not different from cold isotonic responses. Warm hypertonic solution increased albumin flux into the tracheal lumen over a 15-min period to three times that of the control period, persisting for 15 min after replacement with warm isotonic solution. Cooling induces a vasodilation and smooth muscle contraction of the trachea, whereas hypertonic solutions result in vasodilation and, if osmolality is increased with NaCl, an increase in albumin flux into the tracheal lumen. 相似文献
1000.
The effects of fasting on the febrile responses to intravenous injection of bacterial lipopolysaccharide (LPS; endotoxin) of Escherichia coli were investigated in rats. Ad libitum-fed rats (C) produced a biphasic fever with an increase in the temperature difference between brown adipose tissue and colon and shivering activity (SA). Measurement by a direct calorimeter showed no particular changes in heat loss. Rats starved for 4 days (F4) responded to intravenous LPS with a monophasic fever accompanied by an increase in SA only. However the maximal rise in colonic temperature (Tco) did not differ from C rats. Subsequent 2-day fasting reduced SA and the maximal fever height. Endogenous pyrogen (EP) injected intravenously produced a prompt rise in Tco followed by prolonged hyperthermia in C rats. In the F4 rats, there was no such sustained rise in Tco as a result of intravenous EP. The response in Tco to intravenous prostaglandin E2 (PGE2) was the same in fed and starved rats. The administration of LPS, EP, and PGE2 into the lateral ventricle evoked a similar extent of hyperthermia in C and F4 rats. Because the second phase of fever has been shown to occur after pyrogens are translated into a febrile stimulus within the blood-brain barrier, it is assumed that the functional changes of the blood-brain barrier such as in the permeability of pyrogens or in the sensitivity of pyrogen receptors resulted in the absence of the second phase of fever in starved rats. 相似文献