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Plasma glucose concentrations at birth and at two hours of age were measured in 53 infants of insulin-dependent mothers (IDMs). The plasma glucose concentrations at delivery were measured in the mothers of 17 IDMs and in the remaining 36 mothers, glucose was estimated by interpolation from concentrations achieved just before and after delivery. Clinical and laboratory data from the two groups were otherwise similar, so the groups were combined for further analyses. The maternal plasma glucose at delivery correlated positively with the glucose concentration of the IDMs at birth (Q=0.82, p <0.001) and negatively with the glucose concentration at two hours of age (Q= -0.46, p <0.001). Maternal plasma glucose concentration was higher in mothers delivered by caesarean section than in vaginally delivered mothers ( p <0.05). Eleven IDMs became hypoglycaemic at two hours of life (plasma glucose ≥1.7 mmol/1). These infants had higher cord plasma glucose concentrations at birth than those who remained normoglycaemic; the maternal glucose concentration was also higher. None of the IDMs became hypoglycaemic if the maternal glucose concentration at delivery was less than 7.1 mmol/l. In 28 IDMs the simultaneous plasma concentrations of non-antibodybound immunoreactive insulin (IRI) were recorded. Cord plasma IRI correlated with glucose and IRI at two hours of age (Q=-0.73, p <0.001 and Q=0.77, p <0.001, respectively). Cord plasma IRI was higher in IDMs who became hypoglycaemic than in the remaining infants. The results suggest that among the factors which may be responsible for neonatal hypoglycaemia in IDMs a major factor may be the maternal plasma glucose concentration at the time of delivery.  相似文献   
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In keeping with the introduction of market-oriented reforms since the collapse of the Soviet Union, Russia's health care system has undergone a series of sweeping changes since 1992. These reforms, intended to overhaul socialized methods of health care financing and delivery and to replace them with a structure of competitive incentives to improve efficiency and quality of care, have met with mixed levels of implementation and results. This article probes some of the sources of support for and resistance to change in Russia's system of health care financing and delivery. It does so through a national survey of two key groups of participants in that system: head doctors in Russian clinics and hospitals, and the heads of the regional-level quasi-governmental medical insurance Funds. The survey results demonstrate that, on the whole, both head doctors and health insurance Fund directors claim to support the recent health care system reforms, although the latter's support is consistently statistically significantly stronger than that of the former. In addition, the insurance Fund directors' responses to the survey questions tend consistently to fall in the shape of a standard bell curve around the average responses, with a small number of respondents more in agreement with the survey statements than average, and a similarly small number of respondents less so. By contrast, the head doctors, along a wide variety of reform measures, split into two camps: one that strongly favors the marketization of health care, and one that would prefer a return to Soviet-style socialized medicine. The survey results show remarkable national consistency, with no variance according to the respondents' geographic location, regional population levels or other demographic or health characteristics, age of respondents, or size of health facility represented. These findings demonstrate the emergence of well-defined bureaucratic and political constituencies, their composition mixed depending on the particular element of reform under discussion, for and against specific avenues of continuity and change in Russia's health policy. As Russia struggles to devise policy strategies and tactics that balance access, equity, quality, and efficiency, it confronts not only policy choices but also political challenges that look not dissimilar to those faced by health reformers elsewhere in the world.  相似文献   
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A recent paper in Social Science and Medicine (Twigg et al. 50 (2000) 1109) outlined an approach to the estimation of prevalences of small-area health-related behaviour using multilevel models. This paper compares results from the application of the multilevel approach with those derived using the more traditional strategy of the local 'lifestyle' survey. Estimations of smoking prevalence and high alcohol consumption are examined and critical assessments made of both estimation approaches. It is concluded that the alternative method is more suited towards the prediction of smoking rates as opposed to unsafe alcohol consumption.  相似文献   
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Using data from the 1994 Health Survey for England, logistic multivariate multilevel modelling techniques are used to investigate the simultaneous effect of individual demographic characteristics and socio-structural factors on self-reported problem drinking as revealed by CAGE scores and 'unsafe' levels of alcohol consumption. Whilst the influence of key socio-structural variables is broadly similar for both unsafe alcohol consumption and high CAGE scores, there are notable exceptions when results are examined by tenure group: those in the rented sector are more likely to be problem drinkers as revealed by CAGE, but less likely to consume 'unsafe' amounts of alcohol. Both dimensions of drinking behaviour are influenced by the consumption patterns of others in the household, with both likelihoods increasing as the average consumption of others in the household rises. After taking into account individual compositional variables, the research indicates that there is very little evidence for geographical variation remaining in these two dimensions of drinking behaviour. It is found that the proportion of the population whose drinking behaviour may be classed as (potentially) problematic via the CAGE responses is substantially less than the proportion consuming above recommended 'safe' levels. The research concludes, however, that the two measures are broadly similar in their relationship to social and structural variables. Tenure provides an exception to this conclusion and indicates a continuing need to take account of housing circumstances in developing an understanding of drinking behaviour.  相似文献   
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Neonatal screening for phenylketonuria (PKU) has created a problem as females with PKU are reaching child-bearing age. Surveys have revealed that maternal phenylalanine blood concentrations greater than 1200 μmol/l are associated with fetal microcephaly, congenital heart defects and intrauterine growth retardation. It is estimated that as many as 3000 hyperphenylalaninemic females may be at risk of producing these fetal abnormalities. To examine this problem, the international maternal PKU collaborative study was developed to evaluate the efficacy of a phenylalanine-restricted diet in reducing fetal morbidity. Preliminary findings have indicated that phenylalanine restriction should begin before conception for females with PKU planning a pregnancy. Dietary control should maintain maternal blood phenylalanine levels between 120 and 360 μmol/l and should provide adequate energy, protein, vitamin and mineral intake. Pregnant hyperphenylalaninemic females who achieved metabolic control after conception or by the 10th week of pregnancy had a better offspring outcome than anticipated. The results of 402 pregnancies are reviewed.  相似文献   
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Controversies in transfusion medicine. Perioperative hemodilution: pro   总被引:4,自引:0,他引:4  
Hemodilution can obviate the need for allogeneic transfusion in some patients. However, it is only one component of a comprehensive blood conservation program and should be combined with other techniques whenever possible. While most often employed in teenagers and healthy young adults, ANH has been used in small children, the elderly, and patients of all ages who are undergoing cardiac surgery. Extreme caution should be exercised if ANH is used in patients with coronary artery disease or aortic stenosis who are undergoing noncardiac surgery, because their normal compensatory mechanisms are impaired. What usually is a safe and relatively simple procedure can become a disaster if employed in inappropriately selected patients. Careful hemodynamic monitoring and maintenance of normovolemia are critical.  相似文献   
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