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11.
12.
In the early 1970s, the balkanization of the US labor market into “men’s occupations” and “women’s occupations” began to unravel, as women entered the professions and other male-typed sectors in record numbers. This decline in gender segregation continued on for several decades but then suddenly stalled at the turn of the century and shows no signs of resuming. Although the stall is itself undisputed, its sources remain unclear. Using nearly a half-century of data from the General Social Survey, we show that a resurgence in segregation-inducing forms of intergenerational transmission stands behind the recent stall. Far from serving as impartial conduits, fathers are now disproportionately conveying male-typed occupations to their sons, whereas mothers are effectively gender-neutral in their transmission outcomes. This segregative turn among fathers accounts for 47% of the stall in the gender segregation trend (between 2000 and 2018), while the earlier integrative turn among fathers accounts for 34% of the initial downturn in segregation (between 1972 and 1999). It follows that a U-turn in intergenerational processes lies behind the U-turn in gender segregation.

In all late-industrial countries, women and men continue to occupy very different types of jobs, with women concentrated in service and nurturing occupations (e.g., sales clerk and nurse) and men concentrated in manual and analytic occupations (e.g., laborer and computer scientists). The standard sociological account of such segregation treats it as a premodern relic that should gradually disappear as educational opportunities are equalized, egalitarian gender attitudes diffuse, overt and covert forms of employer discrimination are rooted out, and family-friendly workplaces and related labor market reforms are instituted (1, 2). Between 1970 and 1990, these types of institutional reforms indeed seemed to be bearing fruit, with most late-industrial countries experiencing sharp declines in segregation (3).This egalitarian turn proved to be short-lived. By the end of the 20th century, the decline in gender segregation had stalled in many late-industrial countries, including the United States (47). In Fig. 1, we present the US trend using the General Social Survey (GSS), the main data source for our analyses (8). The trend lines in Fig. 1 reveal that the downturn stalled well before integration was achieved (and Fig. 1B additionally suggests a resegregative uptick off this already high baseline). To completely eliminate segregation, ∼60% of US workers would have to shift to a different occupation, a stark result given the stated commitment to gender equality and equal opportunity in the United States. This hypersegregation translates into profound gender gaps in pay, authority, working conditions, and much more (912). Because occupational segregation generates such a wide range of unequal outcomes, it has become a conventional policy target among those who seek to reduce gender inequality.Open in a separate windowFig. 1.The U-turn in occupational gender segregation shown by (A) the index of dissimilarity and (B) a margin-free measure of the gender-by-occupation association. Analysis is based on the 1972 to 2018 GSS using women and men in the labor force, ages 25 to 64 (inclusive), with nonmissing data on age, gender, and occupation. n = 44,640. Occupations are coded with 1970 Census Occupational Classification (see SI Appendix, Appendixes B and D, for details). Trend is smoothed with locally smoothed regression (LOESS) with the span set at 0.75. For the definition of D and A, see Materials and Methods.The long line of research on the sources of the stall proceeds in part from this widely shared (albeit not universal) commitment to reduce gender inequality. Although far from conclusive or exhaustive, the available research suggests that 1) the persisting double burden of domestic work erodes the willingness or capacity of women to hold jobs that entail long hours or overwork (1214); 2) the persistence of norms against women outearning their partners (in marriages between women and men) leads to settling and underachievement (15); 3) the persistence of essentialist beliefs about the types of occupations that women and men are qualified to undertake locks in a conventional division of labor (1, 16, 17); and 4) the continuing tendency of employers to discriminate against mothers (18) and those who participate intermittently in the labor force (19, 20) makes it difficult for women to break into male-typed occupations.* Across these assorted supply-side and demand-side accounts, a common theme is that the easy desegregative gains have been creamed off, that a new equilibrium or natural rate (22) has been reached, and that puncturing this equilibrium may require different or more aggressive countermeasures.This interpretation rests on a distinction between 1) overt and easy-to-attack inequalities and 2) covert and difficult-to-attack inequalities. It is often argued, for example, that overt forms of hiring discrimination against women can be reduced through antidiscrimination law and open hiring practices, whereas subtler or covert forms are not as easy to address, at least with legal remedies. Likewise, the extreme essentialist view that women are utterly lacking in rational faculties was an early casualty of the gender revolution, whereas it has proven more difficult to root out a subtler form of essentialism that presumes that men are more likely than women to be “brilliant” or “geniuses” (23). By this logic, the gender revolution will only be reenergized by developing new interventions that are fine-tuned for the subtler, albeit still very consequential, mechanisms that lie behind gender inequality.This conclusion may well be warranted. It would, however, be premature to adopt this interpretation without a fuller understanding of the institutional sources of the stalling out. It is striking in this regard that none of the foregoing accounts directly features the role of intergenerational processes. To be sure, conventional accounts routinely invoke the segregative effects of gender-biased training, norms, and culture, but the social processes through which gender-biased training is delivered or gender-biased norms and culture are instilled are left unclear and thus may or may not have intergenerational sources. This is an unfortunate omission because it undermines our capacity to remediate well. As it stands, most currently popular interventions do not target intergenerational processes (24), an understandable state of affairs given that relatively little is now known about their role in the stalling out.There is, then, a worrying omission in our research on the gender U-turn. Although this omission might seem surprising, it has to be remembered that the contemporary family is often seen as a prime carrier of new forms of gender egalitarianism and accordingly an unlikely source of the stalling out. The new gender-egalitarian family features mothers who are increasingly likely to work, to commit to bona fide careers, and to espouse liberal attitudes (25). In this conventional characterization of familial change, it is notable that mothers are represented as a main force for change, whereas fathers remain in the background largely carrying on. This raises the possibility that fathers may not always be unfettered agents of egalitarian change and may, to the contrary, be implicated in the stalling out. The purpose of our paper is to explore this segregative-father hypothesis by melding models of segregation and intergenerational transmission.The results will show that the U-turn in the segregation trend is indeed linked to a U-turn in intergenerational processes. As we will discuss, a variety of mechanisms may lie behind the rise of segregative reproduction, yet most of them involve familial processes in some fashion. It follows that insofar as desegregation is a policy objective, it may be strategic to build interventions that address contemporary family processes.The two streams of mobility research upon which our analysis will capitalize are those examining 1) the net effects of mothers and fathers on outcomes and 2) the effects of intragenerational mobility on segregation. The first of these two streams is of course especially relevant when examining the intergenerational sources of segregation (26, 27). In recent decades, there has been a backlash against treating the father’s or “family head’s” occupation as a satisfactory measure of class origins (28), a long-overdue development given that a rising share of children are now growing up in more complicated families with many potential role models (29, 30). This newer line of multiple-parent mobility research has, however, focused mainly on examining the relative size of the effects of mothers and fathers, a type of “horse race” analysis that comes naturally when one seeks to rectify decades of scholarship that ignored mothers altogether. As important and influential as this research is, it cannot directly answer the research question that we are taking on, given that the implications of this horse race for occupational segregation depend on the extent to which class and gender-typing reproduction come together. To understand how intergenerational transmission contributes to gender segregation, we need to know 1) whether mothers are passing on female-typed occupations disproportionately to daughters and 2) whether fathers are passing on male-typed occupations disproportionately to sons. Although the intergenerational transmission of gender-typed aspirations is well understood (31, 32), our research takes the next step of building gendered mobility models that uncover whether actual reproductive practices are affected by the gender of the parent, the gender typing of the occupation, and the gender of the offspring (33).The second stream of mobility research relevant to our analysis examines the effects of intragenerational mobility on gender segregation (34). This line of research, which has a long history (35), examines how women and men move in and out of the labor force over their career, how women and men move in and out of gender-typed occupations over their career, and how such mobility has gendered sources (e.g., sexual harassment, gender discrimination, and the “second shift”). Within this literature, many scholars (36) have examined whether the gender of managers affects hiring and promotion decisions (and hence downstream segregation), a line of questioning that is formally similar to our own interest in whether the gender of the parent affects occupational outcomes. Because parents are engaged in ongoing socialization, aspiration development, human capital investment, and network provisioning, their effects on segregation may well be more consequential than the pinpoint hiring and firing decisions of managers. This is the core rationale for building intergenerational processes into a segregation trend analysis.  相似文献   
13.
大鼠心肌梗死后心肌高迁移率族蛋白HMGB1的时程变化   总被引:5,自引:0,他引:5  
目的 探讨大鼠心肌梗死模型后不同时间高迁移率族蛋白(HMGB1)的时程变化.方法 结扎SD大鼠左冠状动脉前降支造成左室大面积心梗,分别于术后1、2、4、8周测心功能判断造模是否成功后开胸取心脏.分别运用实时荧光定量PCR和Western蛋白印迹技术观察心肌梗死后不同时间点HMGB1在mRNA和蛋白水平的表达变化.结果 心功能检测提示造模成功,心梗大鼠术后早期(1 w)HMGB1 mRNA表达上调(P<0.01),而心梗后期(8周)则表达显著减少(P<0.01).与mRNA水平变化类似,HMGB1蛋白水平在心肌梗死组大鼠术后早期(1~2周)表达水平增加(P<0.01),而心梗后期(8周)则显著下调(P<0.05).结论 HMGB1作为炎症调节因子,在心梗早期对心肌的炎性反应进行调控;并在心梗后期参与调节基因转录,进行心肌修复.在心梗的不同阶段对HMGB1的表达进行干预有望减少心梗并发症,改善预后.提高患者长期存活率.  相似文献   
14.
The possibility of the formation of an alkali–silicate reaction (ASR) is a crucial issue for the service life of concrete. The coexistence of key parameters such as the presence of alkalis, reactive SiO2, humidity, and temperature predetermine the possibility of its formation and application. When an ASR gel forms, it results in the concreting cracking and spalling as well as in the deterioration of its overall properties. The risk of ASR depends on the concentration of alkalis and their mobility, which influence their ability to penetrate the concrete. The objective of this study was to determine the ionic mobility of not only Na+ and K+, but Ca2+ as well, from external sources (0.5 and 1.0 mol/L solutions of Na/K carbonate, nitrate, and hydroxide) to a cementitious matrix as the precursor for ASR. The concentrations of ions in both the immersion solutions (ICP) and the cementitious matrix itself (SEM-EDX) were studied as a function of time, from 0 to 120 days, for leaching, and according to temperature (25 and 40 °C). The reaction products were characterized using SEM-EDX. Different diffusion rates and behavior were observed depending on the anion type of the external alkali source. Both sodium and potassium ions in all the three environments studied, namely carbonate, hydroxide, and nitrate, penetrated into the composite and further into its structure by different mechanisms. The action of hydroxides, in particular, transformed the original hydration products into calcium-silicate-hydrate (CASH) or ASR gel, while nitrates crystallized in pores and did not cause any changes in the hydration product. The driving force was the increased temperature of the experiment as well as the increased concentration of the solution to which the test specimen was exposed.  相似文献   
15.
目的 系统评价运动对预防老年人跌倒的疗效.方法 检索1980年至2020年7月Web of Science、PubMed、Cochrane Library、中国知网数据库有关运动对预防老年人跌倒的随机对照试验,采用Review Manager 5.3对纳入文献进行质量评价,应用R-Studio和Addis 1.16.6...  相似文献   
16.
目的 探讨β-环连蛋白抑制基因1(dapper antagonist of catenin-1,DACT1)对Ⅰ型上皮性卵巢癌迁移侵袭能力的影响及可能机制.方法 免疫组织化学检测Ⅰ型人卵巢癌临床组织中DACT1的表达;采用人黏液性卵巢癌细胞株3AO构建外源性转染DACT1的稳转株,通过划痕实验、Transwell迁移及基质胶侵袭实验检测细胞运动能力;免疫荧光观察DACT1对细胞骨架重塑的影响.结果 Ⅰ型卵巢癌组织中DACT1表达低于正常卵巢组织(P<0.01).外源性转染DACT1后3AO细胞株迁移侵袭能力降低(P<0.01),且腹腔内成瘤能力有所下降,细胞骨架中特化膜结构减少.结论 DACT1对Ⅰ型卵巢癌浸润转移具有抑制效应,其在Ⅰ型卵巢癌组织中的低表达可能与其疾病发生相关.  相似文献   
17.
Abstract

Aims: This study aimed to explore and understand how older adults experience community mobility within an urban Indian context, using a phenomenological approach. Methods: Ten older adults residing in Chennai city participated in this study. The investigator conducted individual, in-depth interviews of 60–75?minutes each. Results: Participants placed high value on community mobility, which contributed to their occupational participation and well-being. Participants identified numerous physical, social and attitudinal barriers to community mobility in their environment, leading to fear and restrictions in community mobility. Conclusion: The study findings underscore the need for the development of age-friendly communities within Indian society to promote occupational justice for older adults. Occupational therapists in India can intervene at the government, community, family and individual levels to enable older adults’ community mobility and occupational participation. Future research to investigate context-specific interventions to facilitate older adults’ community mobility is recommended.  相似文献   
18.
SUMMARY

Objective. To examine the relationship between driving status and demographics, health status, functional status, and mental and psychosocial status.

Methods. The Consumer Assessment Study Interview Battery (CAS-IB), administered to 697 community dwelling men and women aged 60 to 106, included instruments to measure health, functional status, and mental and psychosocial status. These variables were compared for three groups based on driving status: those still driving, those who had ceased driving, and those who had never driven.

Results. Differences among the three groups were found for age, race, gender, income, education level, home ownership, and living situation. Differences among the three groups were found for many measures of health status and all measures of functional, mental, and psychosocial status.

Conclusions. Declines in health, functional ability, and cognition are associated with driving cessation. Availability of alternative forms of transportation, whether supplied by the community, friends, or family, may mitigate additional declines in health, function, and psychosocial status.  相似文献   
19.
SUMMARY

On December 1 and 2, 2003, 63 international experts on older driver issues met to examine three critical issues related to the safe mobility of older drivers. Conference participants addressed standards and protocols for screening and evaluating the skills of older drivers. For drivers judged to lack the necessary skills to drive safely, participants addressed methods of remediation that could enable older persons with limited cognitive or physical abilities to continue to drive. For those persons whose skills are judged inadequate for safe driving, conference participants addressed the question as to how best to counsel individuals and their caregivers on practical alternatives to driving.

Consensus was achieved as to the current methods for best assessing and screening drivers, remediation techniques, and providing advice and counsel for those persons and the caregivers as to appropriate actions for those no longer able to drive safely.  相似文献   
20.
Abstract

Background: At the hospital studied, weekend physiotherapy (WEPT) is routinely provided and in 2013 WEPT was increased from one (PRE) to three (POST) physiotherapists (PTs) to cover intensive care and ward patients. Aims: (1) To evaluate the impact of increased WEPT on patient volumes, treatments provided and conditions treated in critical care and wards; and (2) to understand the PTs’ perspectives on the new coverage model. Methods: A mixed methods design was utilized. The quantitative component consisted of retrospective document reviews of all weekend patients treated January 1–May 5 (PRE) and May 11–December 31 (POST). The qualitative component used a questionnaire to collect staff feedback. PRE–POST comparisons were conducted using χ2 or Mann–Whitney U tests. Results: Significant (p?=?0.00) increases POST were seen in number of patients treated, number of mobility treatments provided and number of post-surgical patients seen in both clinical areas. The majority of survey respondents reported feeling adequately trained, but had concerns regarding the impact of increased WEPT on work-life balance. Conclusion: PTs perceived enhanced service was beneficial for continuity of weekday care and improved patient function. Future studies need to focus on measuring the effect of increased weekend provision on outcomes, preventing complications and length of stay.  相似文献   
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