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101.
德国医院新标准新概念   总被引:4,自引:0,他引:4  
本文评述了德国医院最新标准VDI 2176中的"医院建筑设施--供热、通风与空气调节",特别对VDI标准的新概念、最新定义的卫生级别、供热、通风与空气调节新措施和手术室验收进行了介绍,并对标准中这些措施与感染控制问题的关系进行了讨论.  相似文献   
102.
Surveillance of acute flaccid paralysis (AFP) is the golden strategy recommended by the WHO to verify the condition of polio eradication in a country. Because of the difficulty to detect all of the expected AFP cases and to reach the target incidence of 1/100,000 requested by WHO, the surveillance of enteroviruses in the population has been adopted by several countries as an important additional method to verify the absence of wild-poliovirus circulation. To complete the results of AFP surveillance set up in Italy in 1996, we have conducted a wild poliovirus surveillance by examining stool samples from 1551 healthy children aged less than 5 years, collected during the period January 1997 to January 1998. The children were from three cities (Parma, Rome and Bari) located in northern, central and southern Italy. Thirty-nine polioviruses, 72 non-polio enteroviruses and 50 enteric, non-entero (NE), viruses were isolated from stool specimens. Polioviruses identified were nine type 1, seven type 2 and twenty-three type 3. Characterization of isolates by both antigenic and molecular methods showed that all polioviruses were of vaccine origin. As expected, most polioviruses, especially types 2 and 3, presented retromutations known to be associated with loss of the Sabin attenuated phenotype. The results of this study support the data obtained from the active AFP surveillance conducted in Italy in the same period – on the absence of paralytic disease due to wild poliovirus – and altogether demonstrate the effectiveness of the vaccination program.  相似文献   
103.
The spontaneous alternations of “dwarf” mice estimated in a Y maze proportioned to the size of control mice demonstrated the necessity of reducing the size of the apparatus for testing the “dwarf” mice. Tested in a maze of reduced dimension, the “dwarf” mice showed a significant deficit in this task but only in a T shaped maze, and not in a Y shaped maze. For one month after weaning, “dwarf” and control mice were reared in either an enriched or an impoverished environment. These rearing conditions did not modify the spontaneous alternation of control mice whether estimated in a T or a Y maze, but they significantly altered the behavior of “dwarf” mice, yet only when evaluated in a T maze: “isolated” “dwarf” mice alternating less than “enriched” “dwarf” mice. It is suggested that this behavioral profile displayed by “dwarf” mice in spontaneous alternation might be explained by a deficit in perceiving, integrating and/or utilizing complex spatial information.  相似文献   
104.
105.
Objective :To investigate the sources of lead in the environment in children with elevated blood, with the help of a Field Portable X-Ray Fluorescence Analyzer.Methods : One hundred and seven school children were chosen for this study on a random basis, from Mangalore and Karnataka. Their blood lead was analyzed. Of the cases analyzed, 10 students whose blood lead level was more than 40 μg/dl were investigated using a field portable X-Ray Fluorescence Analyzer. This is the first time such a device has been available for this purpose in India.Results: The ‘likely’ source of lead exposure could be determined in eight cases which was from the immediate environment of the children like ‘lead-based’ paint on surfaces in the house, on playground and other exterior equipment; lead storage batteries, contaminated dust and soil and other lead-containing substances.Conclusion: The use of an X-Ray Fluorescence Analyser appeared to be useful in determining the source of lead  相似文献   
106.
OBJECTIVE: This study describes processes and outcomes of midwifery care through narratives told by exemplary midwives. DESIGN: Narrative analysis. SETTING: Midwifery practices in hospital, birth center, and home settings. PARTICIPANTS: Purposive sample of 14 midwives drawn from a large national Delphi panel on exemplary midwifery practice. DATA ANALYSIS: Systematic analysis of interview data was conducted until interpretive consensus was achieved across all text and codes. Results were compared with two prior qualitative studies conducted by the first author on midwifery practice for congruence and emergence of new findings. RESULTS: The support of normalcy was identified as a significant process of midwifery care during labor and birth. CONCLUSIONS: The midwives believed that birth is normal, and many of their actions were specifically aimed toward the support of it as a physiologic, rather than pathologic, process. Through their words, we see subtle care processes focused on meeting a woman's individual needs and tapping into her personal strength. Implications for practice and further research to link their approach to caring for women with perinatal outcomes are reviewed.  相似文献   
107.
The aim of previous research into the causes of allergic diseases, including asthma was mostly to identify potential risk factors in the environment. No major risk factors have been identified, however. Over the past 10 years, focus has, therefore, more been directed towards protective factors that could enhance the development of tolerance to allergens which were previously encountered early in life, but are now lost in modern affluent societies. In particular, the role of childhood infections has been discussed, but so far these studies have not been conclusive. Recent epidemiological studies and experimental research suggest that the microbial environment and exposure to microbial products in infancy modifies immune responses and enhances the development of tolerance to ubiquitous allergens. The intestinal microflora may play a particular role in this respect, as it is the major external driving force in the maturation of the immune system after birth, and animal experiments have shown it to be a prerequisite for normal development of oral tolerance. Recent studies have shown differences in the composition of the microflora between healthy and allergic infants in countries with a high and low prevalence of allergies and between healthy and allergic infants within such countries. These differences are apparent within the first week of life and thus precede clinical symptoms. The use of live microorganisms that might be beneficial to health has a long tradition and the safety is well documented. Very recently, several prospective intervention studies, modifying the gut flora from birth have yielded encouraging results and may suggest a new mode of primary prevention of allergy in the future.  相似文献   
108.
109.
In amphibians, large changes in tissue corticosterone content (caused by treatment with large doses of hormone) alter tadpole growth and development, but the effects of smaller changes on growth, development, behavior, and morphology are unknown. In the current study, we exposed pre-metamorphic Rana pipiens tadpoles to moderate doses (62 and 125 nM) of exogenous corticosterone by adding it to the rearing water. We then analyzed effects on growth, development, behavior, morphology, and the endogenous corticosterone response to exogenous adrenocorticotropic releasing hormone (ACTH). A 50% elevation in whole-body corticosterone content was associated with slowed growth and development, increased tail muscle depth, and a diminished corticosterone response to ACTH. Behavior was unaffected by corticosterone administration. Treatment with the corticoid synthesis inhibitor metyrapone (MTP) reduced whole-body corticosterone content by 50% and was associated with increased size at metamorphosis but no change in time to metamorphosis. Our findings support the hypothesis that corticoids can mediate growth, developmental, and morphological responses of tadpoles to changing environmental conditions. Our results also demonstrate that even small changes in corticosterone content can have important implications for amphibian fitness.  相似文献   
110.
Naphthalene—an environmental and occupational toxicant   总被引:9,自引:0,他引:9  
For many years naphthalene had been considered as a non-carcinogenic polycyclic aromatic hydrocarbon (PAH). Airborne naphthalene concentrations have always been observed to be below the limit values of various national committees, such as the threshold limit value (TLV) of the American Conference of Governmental Industrial Hygienists (ACGIH) and the MAK of the Deutsche Forschungsgemeinschaft (DFG) (10 ppm). Since 2000, when the US National Toxicology Program revealed clear evidence of the carcinogenic activity of naphthalene in rats, international agencies [the International Agency for Research on Cancer (IARC), the US Environmental Protection Agency (US EPA), DFG] have reclassified naphthalene as a potential human carcinogen, and the European Union (EU) is currently preparing a new risk assessment report. It is presently unknown how to protect humans from health risks resulting from occupational and environmental naphthalene exposure. Knowledge about the external and internal exposure of humans serves as the key determinant in a comprehensive risk assessment. We review here ambient monitoring studies concerning the external naphthalene exposure that results from ubiquitous environmental sources (indoor and outdoor air, water, soil, food) and from a variety of critical workplaces (coking plants, creosote impregnation, distillation of coal tar and naphthalene, manufacture of refractories, graphite electrodes, aluminium and mothballs). Based on results of ambient monitoring studies published so far, a new hygiene-based exposure limit of 1.5 mg naphthalene per cubic metre of air (0.3 ppm) is proposed. Furthermore, results from biological monitoring studies are summarised in this article. The internal burden was almost exclusively determined by means of the urinary metabolites 1-naphthol and 2-naphthol, but it is currently not possible for one to evaluate a biological tolerance level (BAT) or a biological exposure index (BEI). Based on the toxicokinetics and metabolism of naphthalene, the central question on its carcinogenicity is briefly sketched. Naphthoquinones play an important role in this context. Their adducts with macromolecules may be the parameters of choice for the estimation of effects to human health.  相似文献   
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