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排序方式: 共有830条查询结果,搜索用时 46 毫秒
741.
An Alcolmeter Pocket Model breath alcohol device, based on an electrochemical (fuel cell) oxidation principle for ethanol analysis, has been evaluated under in vitro conditions. The result of a test is displayed on an analogue meter within 20 – 30 seconds after sampling; replicate tests may be made within 3 – 5 minutes. The electrochemical detector used was found to respond to acetaldehyde, methanol, isopropanol and n-propanol vapours besides ethanol, but it was insensitive to acetone vapour. The Alcolmeter response with a 0 – 2.0 mg/ml scale was linearly related to ethanol vapour concentration up to 1.0 mg/ml blood alcohol equivalent concentration; above this level the response was curvilinear, the Alcolmeter reading being too low. The standard deviation of an ethanol vapour determination in vitro was ±0.0175 mg/ml at a mean concentration of 0.902 mg/ml. The accuracy of the device expressed as percent recovery at 0.50, 1.0 and 1.4 mg/ml blood alcohol concentrations was 96.8%, 98.3%, and 88.3%, respectively. When the Alcolmeter was calibrated at 0.50 mg/ml and used occasionally each day over an 18-day period, the drop in initial calibration was 0.01 mg/ml per week.  相似文献   
742.
Healthy men drank 0.51, 0.68, and 0.85 g of ethanol per kilogram of body weight as neat whisky in the morning after an overnight fast. During 6 to 8 h after the whisky was consumed, nearly simultaneous specimens of fingertip blood and pooled bladder urine were obtained for analysis of ethanol using an enzymatic method. The mean ratios of ethanol concentration [urine alcohol concentration (UAC)/blood alcohol concentration (BAC)] were mostly less than unity during the absorption phase. The UAC exceeded the BAC in the postpeak phase. The mean UAC/BAC ratios varied between 1.4 and 1.7 when the BAC exceeded 0.50 mg/mL. When the BAC decreased below 0.40 mg/mL, the UAC/BAC ratios increased appreciably. The mean UAC/BAC ratios of ethanol were not dependent on the person's age between the ages of 20 and 60 years old, but there were large variations within the age groups. In apprehended drinking drivers (N = 654) with a mean BAC of 1.55 mg/mL, the UAC/BAC ratio of ethanol varied widely, with a mean value of 1.49. In 12 subjects (3.2%), the ratio was less than or equal to unity. In a second specimen of urine obtained approximately 60 min after an initial void (N = 135), the mean UAC/BAC ratio was 1.35 (standard deviation = 0.17). The magnitude of the UAC/BAC ratio of ethanol can help to establish whether the BAC curve was rising or falling at or near the time of voiding. The status of alcohol absorption needs to be documented if drinking drivers claim ingestion of alcohol after the offence or when back-estimation of the BAC from the time of sampling to the time of driving is required by statute.  相似文献   
743.
The U.S. Department of Defense develops policies, plans, and allocates resources using PPBS—the Planning, Programming, Budgeting System. The system is used to formulate both long-range policies and resource allocation plans. The scope of DoD's activities make this an enormous undertaking. It is also politically charged because of the role of Congress in determining the department's budget and activities. Therefore, complexity and plurality characterize these processes.  相似文献   
744.
745.
Jones  Philip  Hudson  John 《Public Choice》1998,94(1-2):175-189
This paper explores the proposition that political parties reduce the ‘transaction costs’ of electoral participation. Political parties provide a low cost signal of a candidate's policies and personal characteristics and, in this way, reduce voters' information costs. With reference to ‘transaction cost economics’, political parties offer an ‘implicit contract’ between voters and politicians and thereby reduce the scope for opportunism by politicians. This impact on transaction costs is important in any evaluation of public policy towards political parties.  相似文献   
746.
Reviews     
Israel Getzler, Kronstadt 1917–1921: The Fate of a Soviet Democracy. London: Cambridge University Press, 1983, xii + 296 pp. £25.00.

Hans Dieter Seibel and Ukandi G. Damachi, Self‐Management in Yugoslavia and the Developing World, London: Macmillan, 1982, 316 pp. £20.00. Fred Singleton and Bernard Carter, The Economy of Yugoslavia, London: Croom Helm, and New York: St. Martin's, 1982, 279 pp. £19.95.

Steven Rosefielde, False Science: Underestimating the Soviet Arms Buildup. An Appraisal of the CIA's Direct Costing Effort, 1960–80. New Brunswick and London: Transaction Books, 1982, xxi + 340 pp. p/b $14.95.

Donald S. Zagoria (ed.), Soviet Policy in East Asia, London: Yale University Press, 1982, xiii+360 pp. £21.00.

Aryeh Y. Yodfat, The Soviet Union and the Arabian Peninsula, London: Croom Helm, 1983, 191 pp. £13.95.

David Lane, The End of Social Inequality? Class, Status and Power Under State Socialism, London, Boston and Sydney: George Allen and Unwin, 1982, x+208 pp. h/b £12.95. p/b £4.95.

P. J. Potichnyj and J. S. Zacek (eds.), Politics and Participation under Communist Rule, New York: Praeger Special Studies, 1983, xvii+282 pp. $29.95.

Vladimir G. Treml, Alcohol in the USSR: A Statistical Study, Durham, N.C.: Duke Press Policy Studies, 1982, xiii + 103 pp. $27.75.

R. Amann and J. M. Cooper (eds.), Industrial Innovation in the Soviet Union, New Haven and London: Yale University Press, 1982, xxix+526 pp. £33.00.

Malcolm R. Hill, East‐West Trade, Industrial Co‐operation and Technology Transfer, London: Gower Publishing, 1983, xviii+217 pp. £15.00.

Roy Medvedev, (translated by Brian Pearce), Khrushchev, Oxford: Basil Blackwell, 1982, x + 292 pp. £9.50.

Roger Munting, The Economic Development of the USSR, London: Croom Helm, 1982, 228 pp. (with one map and 54 tables). £13.95.

David Rousset, The Legacy of the Bolshevik Revolution: A Critical History of the USSR, volume 1, London/New York: Allison and Busby, 1982, translated by Alan Freeman, 333 pp. h/b £13.95, p/b £5.95.  相似文献   

747.
The indiscriminate promotion of infant formula in 3rd world countries frequently increases women's fertility as well as resulting in a direct risk to infants. The fertility effect of the decline of breastfeeding in the 3rd world over the last 30 years has only recently been examined. Preliminary study results show that it is not simply the presence or absence of breastfeeding which counts but the amount of suckling which takes place. Mothers who nurse often, on demand, return to fertility much later than those who do not feed at night, or who stick to regular, separate feeding intervals. The contraceptive effect of breastfeeding comes from the release of a hormone (prolactin) directly after stimulation of the nipples, which in 5-15 minutes increases almost 20 times its normal level in the bloodstream. Prolactin is short lived in the blood so that half of this quantity will have vanished 10-30 minutes after suckling stops; regular feeding is needed to keep the level sufficiently high to inhibit fertility. If a woman does ovulate, it may be what is termed and "inadequate ovulation" where the corpus luteum does not function normally and even if the egg is fertilized will not permit the pregnancy to continue. A study on this theme was conducted among the Kung people of northwestern Botswana where there was an unusually low natural fertility--about 4.7 live births/woman, well spaced out. The children were normally weaned at 3-years old, and daytime suckling followed an unusual pattern. It was very brief, a few seconds or minutes, and very frequent. Breastfeeding began to decline during the child's 2nd year and fertility shortly returned. The World Fertility Survey concludes that "on average, breastfeeding for 1 months adds 1 week to the birth interval." In countries like Colombia and Panama, which are heavily Westernized in the urban areas and where traditional cultures are largely eroded, aggressive Western provision and marketing of artificial contraceptives may just offset the aggressive Western marketing of breastmilk substitutes, as far as fertility is concerned. In other developing countries bottle feeding may have increased unwanted pregnancies.  相似文献   
748.
749.
750.
A large part of the literature on budgeting in the United States is concerned with reform. The goals of proposed reforms are couched in similar language - economy, efficiency, improvement, or just better budgeting ... However, any effective change in budgetary relationships must necessarily alter the outcomes of the budgetary process. Otherwise, why bother? Far from being a neutral matter of better budgeting, proposed reforms inevitably contain important implications for the political system, that is, the who gets what of governmental decisions (Wildavsky, 1961: p. 186). ... budgeting is a subsystem of politics, not vise versa - because of the current tendency to overload budgeting. As much as I respect the importance of budgeting and the talents of budgeteers, to substitute budgeting for governing will not work (Wildavsky, 1992b: p. 439).  相似文献   
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