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31.
Comparison of the use of nalbuphine and fentanyl during third molar surgery   总被引:1,自引:0,他引:1  
In a double-blind, randomized plan of drug administration, nalbuphine, fentanyl, and a placebo were compared for efficacy in sedation and analgesia during third molar removal. Fifty-eight patients participated in this study. Using accepted intravenous sedation and surgical techniques, fentanyl and nalbuphine were found to be better than placebo for anxiety and pain control in third molar surgery. Fentanyl had a longer duration of pain relief postoperatively than did nalbuphine. The study confirmed the need for a narcotic supplement to sedation techniques for third molar surgery.  相似文献   
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This paper examines medical malpractice law as it applies to medically necessary oral health care. The basic legal concepts and reported cases involving medically necessary oral health care are reviewed. It is concluded that dental professionals and consumer advocates must advance their educational and legislative advocacy efforts so that health professional colleagues and the public will become aware of the importance of these services and insurers will routinely include coverage of medically necessary oral health care in their medical and dental policies. While failure to provide medically necessary oral health care can be violative of patient rights and legally actionable, medical malpractice litigation should always be the behavior modifier of last resort.  相似文献   
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A chondral growth/force response curve predicts how intact hyaline cartilage plates grow in vivo under typical peak mechanical unit loads and gradients thereof in healthy immature mammals. Growth under tension would increase as tension rises from zero to a level that damages the tissue. Under compression, growth would increase as the load rises from zero to a level at which growth becomes maximal (the growth-ascending limb of the curve). Further increases in compression loads retard growth and large enough increases can stop it entirely (the growth-descending limb of the curve). For equal changes in loads, the smallest growth change would occur under tension; the largest change would occur on the growth-descending part of the curve. Under zero load a respectable "baseline growth" still occurs. Those effects are superimposed on inherent differences in growth potential of different chondral plates, differences that are determined partly in utero and by the genome. The curve's features can explain many anatomical facts, including the ball-and-socket ankle, joint alignment in the valgus-varus sense, hip dislocations in spasticity, different epiphyseal heights, short bones in paralysed limbs, long bone overgrowth after fractures, why some joint surfaces remain concave and others convex throughout growth, and why some growth plates are domed instead of flat. The above phenomena can be expressed mathematically, and a phenomenologic basic logical framework for doing that is suggested.  相似文献   
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From the nature of a bone's endload and its local surface strains, the theory computes a modeling operator, Gamma (gamma), that predicts whether mechanical factors will cause lamellar bone modeling drifts, and where and of what kind. A given mechanical bone strain history then provides a separate modeling rate function, M, to specify the rate of such modeling drifts as fractions of the largest possible ones. Multiplying the two functions, e.g., gamma.M, then predicts mechanically controlled bone modeling responses for cortical and trabecular bone, both quantitatively and qualitatively. The theory correctly predicts each of the 6 known "principal adaptations" of lamellar bone, which provide a critical test of any such theory for this organ. The theory accounts for biologic, biomechanical, and clinical-pathologic knowledge not available in Wolff's time nor accounted for by most biomechanicians since. Existing proven methods can provide all numerical data needed to satisfy the theory's mathematical equations and already suggest provisional values for most of them. Its originator views the theory as the kernel of more and better theories to come rather than a finished work, a kernel that suggests a new and in some respects novel logical framework for analysing the problems, and a kernel that invites critique, refinement, and/or exploitation by others.  相似文献   
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Many youth, their parents, and social services regard the unification of the family as the most desirable outcome for youth in out-of-home placements. This goal is often difficult to achieve because the families of these troubled/troubling youths are often severely dysfunctional, with multiple problems. A group process model for serving natural parents of youth in placement is described which, in conjunction with one-on-one interactions with professionals, appears to have a positive impact on these families and on youths' return home. Group components that seem particularly important are described, including attendance by invitation only, public commitment to attend and participate, reminder prompts, transportation support, babysitting support, refreshments, opportunity to visit with their child, defined staff roles, an empowering approach, and starting where the parent is. The group process maintained a relatively high level of both attendance and participation by the targeted parents. Participants tended to achieve most goals that they set in the group. Our experience indicates that interventions with natural parents of troubled youth can enable even a very dysfunctional family to improve enough to receive youth back into their home.The authors are grateful for the assistance of Sharon Estill, Jim Bernardo, Anita Mentzer, Dave Walker, and Suni Dague-Lyman for assistance in collecting the data reported here. Debbie Buchanan and others have been a great assistance in transporting families.  相似文献   
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The authors investigated factors that predict intention to take a genetic test for Alzheimer's disease (AD). The 449 men and women were surveyed in two groups: (a) those told that a positive result meant a 90% chance of developing AD (increased certainty) and (b) those told that a positive result meant a 50% chance of developing AD (decreased certainty). Participants completed measures of the Theory of Planned Behavior (TPB), anticipated regret, risk perception, likelihood of taking a genetic test for cancer, and AD risk factors. Just over 50% of the variance in intentions was related to TPB variables, likelihood of taking a genetic test for cancer, number of people the participants knew who had AD, experimental condition, and anticipated regret. The subjective norm was the strongest predictor of intention in the increased certainty group, whereas positive belief was the strongest predictor in the decreased certainty group.  相似文献   
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Summary For the experiments reported in this study, recordings were obtained from 246 single units in the middle lateral suprasylvian visual area (LS) of 13 cats. 49 of these cells were subjected to detailed quantitative analysis. The receptive field (RF) organization was examined for directionally specific cells by presenting moving single spots on large moving random dot backgrounds. A cell's response to an optimal spot (in terms of size, direction, velocity) moving on a stationary background inside the excitatory RF (ERF) was compared to in-phase (same direction, same velocity) and anti-phase (opposite direction, same velocity) movement of spot and background. In-phase movement resulted in inhibition of the cell's response (3–100%) in 94% of the cells, while anti-phase movement led to reduced inhibition in 52% of the cells or to facilitation (0.5–327%) in 39% of the cells. By changing the direction of background motion with respect to that of the spot, the directional tuning of the in-phase inhibition and anti-phase facilitation effects was determined.We were able to manipulate the size of the background effects by masking out the background for various proportions of the ERF, and maximizing them by restricting background stimulation to the large inhibitory RF (IRF) surrounding the ERF. These results could be best accounted for by a double-opponent-process mechanism with both RF center and RF surround being directionally selective, but with opposite polarity. It is suggested that this type of mechanism could be involved in the processing of object motion.Partially supported by an NSERC University Research Fellowship (U 0057) and an ARC equipment grant to M. von Grünau and by an NSERC Grant to B. J. Frost (A 0353)  相似文献   
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