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991.
992.
Any organ which is allocated to one individual represents a missed opportunity for someone else. Given the important repercussions which organ allocation policies inevitably have for certain people, any prioritization policy should rest on a solid argumentative basis. In this study, we analyze the widespread practice of prioritizing pediatric patients in the allocation of kidneys. While official policy documents offer no arguments in support of pediatric priority, such arguments can be found in the academic literature on pediatric renal transplantation. Our study is the first to bring together and critically analyze these. We identify five commonly cited arguments and show that none of these succeeds in justifying pediatric priority policies. We argue that the legitimacy of such policies may be further undermined by their potential adverse effects on both adults and children.  相似文献   
993.
The self-report Drug Attitude Inventory (DAI), in 30- and 10-item versions, provides unique information of clinical relevance for monitoring treatment adherence among people diagnosed with schizophrenia. The primary purpose of this paper was to evaluate the 10-item version among patients living in sheltered housing. Data were collected among 68 persons living in sheltered housing, most of them (82%) diagnosed with schizophrenia, 6% with non-organic psychoses, and 12% with other diagnoses. The dichotomic response format of the original DAI-10 was replaced by a 4-point Likert scale, in order to improve the resolution of the scale. Over 90% of the participants produced meaningful scores. A factor analysis suggested a 2-factor orthogonal structure: one highly homogenous factor (5 items) reflected wanted effects of the drug and displayed a bimodal distribution; one factor (3 items) reflected side effects. One item concerned the perceived control over one's drug treatment, which is a key clinical issue. One item was conceptually ambiguous and displayed no correlations with the other items. On the basis of the results we suggest cut-off scores which indicate the need for three kinds of adherence-improving interventions. Summing up, by dropping one item and using a Likert scale response format, the resulting instrument, DAI-9, appears to be an easy-to-use self-report instrument for monitoring drug attitudes and to identify needs for treatment adherence interventions among seriously ill patients.  相似文献   
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«Mental disability management within occupational health surveillance».Introduction:The management of workers with mental disability is a current topic of great interest. The aim of the article is to report the experience of managing cases of employees with mental disabilities in an Italian university hospital and to describe the preventive measures adopted and the therapeutic programs carried out.Methods:A group of 100 workers suffering from psychiatric disorders has been included in a medical surveillance program lasting at least 6 months. The workers were followed up within a protocol that included psychiatric visits, psychotherapeutic interventions, visits by the occupational physician and medico-legal evaluations. Evaluation scales of disease severity and treatment efficacy (CGI) and overall functioning (GAF) were administered at the baseline and after 6 months of follow-up.Results:The sample was mainly composed of nurses (44%) and nursing assistants (24%) and the most commonly diagnosed disorders were mood and anxiety disorders. Participation in the medical surveillance program with the implementation of specific therapeutic strategies and organizational interventions resulted in a statistically significant reduction in the severity of the disease and an improvement in overall functioning and made it possible to keep the job and place of work in almost all cases.Discussion:The results of this experience allow us to affirm that the integration of skills is a valid tool both for the multidisciplinary diagnostic assessment and for the monitoring and management of workers with mental disability under periodic health surveillance.Key words: Psychic disability, health surveillance, occupational medicine, mental disorders  相似文献   
998.
Background Prostate cancer is a frequently diagnosed cancer and made up 6% of male cancer deaths globally in 2008. Its incidence varies more than 25-fold worldwide, which is primarily attributed to the implementation of the prostate-specific antigen (PSA) test in developed countries. To reduce harm of overdiagnosis, most international guidelines recommend surveillance programmes. However, this approach can entail negative psychosocial consequences from being under surveillance for an (over)diagnosed prostate cancer.Aim To explore men’s feelings and experiences in a surveillance programme.Design and setting Qualitative study with Danish men diagnosed with asymptomatic prostate cancer Gleason score ≤ 6, who are in a surveillance programmeMethods 12 semi-structured, individual interviews were conducted and analysed with systematic text condensation and selected theories.Results Most informants reported that they were astonished at the time of diagnosis. They were aware of the small likelihood of dying from cancer, but in some cases, the uncertainty created ambivalence between knowing and not knowing. The men expressed their risk awareness in different ways: a realization that life does not last forever, uncertainty towards the future, a feeling of powerlessness, and a need for control.Conclusions The men in this study had substantial psychosocial consequences from being labelled with a cancer diagnosis. Bearing these men’s high risk of overdiagnosis in mind, it is important to discuss whether the harms of this diagnosis outweigh the benefits. The psychosocial consequences of being in a prostate cancer surveillance programme should be explored further.

KEY POINTS

  • Current awareness: The number of men living with an asymptomatic prostate cancer has increased the last 20 years after the implementation of the PSA test.
  • Main Statements: Men living with an asymptomatic, low-risk prostate cancer experience negative psychocosial consequences
  • GPs should consider the possible negative psychosocial consequences in their decision-making of measuring the PSA level
  相似文献   
999.

Background

Prostate-specific antigen (PSA) measurement in midlife predicts long-term prostate cancer (PCa) mortality among white men.

Objective

To determine whether baseline PSA level during midlife predicts risk of aggressive PCa in black men.

Design, setting, and participants

Nested case-control study among black men in the Southern Community Cohort Study recruited between 2002 and 2009. A prospective cohort in the southeastern USA with recruitment from community health centers. A total of 197 incident PCa patients aged 40–64 yr at study entry and 569 controls matched on age, date of blood draw, and site of enrollment. Total PSA was measured in blood collected and stored at enrollment.

Outcome measurements and statistical analysis

Total and aggressive PCa (91 aggressive: Gleason ≥7, American Joint Committee on Cancer stage III/IV, or PCa-specific death). Exact conditional logistic regression estimated odds ratios (ORs) with 95% confidence intervals (CIs) for PCa by category of baseline PSA.

Results and limitations

Median PSA among controls was 0.72, 0.80, 0.94, and 1.03 ng/ml for age groups 40–49, 50–54, 55–59, and 60–64 yr, respectively; 90th percentile levels were 1.68, 1.85, 2.73, and 3.33 ng/ml. Furthermore, 95% of total and 97% of aggressive cases had baseline PSA above the age-specific median. Median follow-up was 9 yr. The OR for total PCa comparing PSA >90th percentile versus ≤median was 83.6 (95% CI, 21.2–539) for 40–54 yr and 71.7 (95% CI, 23.3–288) for 55–64 yr. For aggressive cancer, ORs were 174 (95% CI, 32.3–infinity) for 40–54 yr and 51.8 (95% CI, 11.0–519) for 55–64 yr. A composite endpoint of aggressive PCa based on stage, grade, and mortality was used and is a limitation.

Conclusions

PSA levels in midlife strongly predicted total and aggressive PCa among black men. PSA levels among controls were similar to those among white controls in prior studies.

Patient summary

Prostate-specific antigen (PSA) level during midlife strongly predicted future development of aggressive prostate cancer among black men. Targeted screening based on a midlife PSA might identify men at high risk while minimizing screening in those men at low risk.  相似文献   
1000.
Magnetic superconductors are specific materials exhibiting two antagonistic phenomena, superconductivity and magnetism, whose mutual interaction induces various emergent phenomena, such as the reentrant superconducting transition associated with the suppression of superconductivity around the magnetic transition temperature (Tm), highlighting the impact of magnetism on superconductivity. In this study, we report the experimental observation of the ferromagnetic order induced by superconducting vortices in the high-critical-temperature (high-Tc) magnetic superconductor EuRbFe4As4. Although the ground state of the Eu2+ moments in EuRbFe4As4 is helimagnetism below Tm, neutron diffraction and magnetization experiments show a ferromagnetic hysteresis of the Eu2+ spin alignment. We demonstrate that the direction of the Eu2+ moments is dominated by the distribution of pinned vortices based on the critical state model. Moreover, we demonstrate the manipulation of spin texture by controlling the direction of superconducting vortices, which can help realize spin manipulation devices using magnetic superconductors.

The coexistence of superconductivity and magnetism has been a long-standing issue in the field of superconductivity due to the antagonistic nature of these two ordered states. Therefore, magnetic superconductors, exhibiting both behaviors simultaneously, have played an important role in the study of their interaction. Various novel phenomena have been reported in magnetic superconductors containing rare earth elements (R) such as Ho and Er, for example, RRh4B4 (Tc ∼9 K and Tm ∼1 K) (1), RMo6S8 (Tc ∼2 K and Tm ∼0.2 to 1 K) (2), and RNi2B2C (Tc ∼5 to 10 K and Tm ∼2 to 6 K) (3, 4), including reentrant superconducting transition, anomalous temperature dependence of the upper critical field, and enhanced vortex pinning (or critical current density [Jc]) associated with the magnetic transition. All have contributed significantly to the development of superconductivity research.Recently, iron-based superconductors containing Eu (Eu-IBSs) have attracted attention as a new class of magnetic superconductors (5). Eu-IBSs are characterized by higher Tc (up to 37 K) and Tm (∼15 to 20 K) compared to other magnetic superconductors. The coexistence of superconductivity and magnetism extends over a wider range of temperatures and magnetic fields, allowing us to conduct experiments using various probes. For example, in the case of EuFe2(As,P)2 (6) and Eu(Fe,Rh)2As2 (7), where the Eu2+ moments exhibit ferromagnetic ordering, observations of a spontaneous vortex state, the domain Meissner state, and a vortex-antivortex state were reported using magnetic force microscopy (8) and magnetization measurements (9). Furthermore, for EuRbFe4As4 (10, 11) with a Eu2+ helical order (12), it was proposed that the Eu-spin subsystem serves as an internal pump for the magnetic flux based on magneto-optical imaging results (13, 14). In addition, optical conductivity measurements (15) and scanning Hall microscopy (16) revealed that the temperature dependence of the superfluid density shows a dip feature around Tm, which was attributed to the weakening of superconductivity at the magnetic transition.Most of these peculiar phenomena in magnetic superconductors are considered to reflect the impact of magnetism on superconductivity. On the contrary, an example of the influence of superconductivity on magnetism is the shrinkage of magnetic domains associated with the superconducting transition (17), which is favorable for superconductivity, as it reduces the internal magnetic field. Meanwhile, in a type-II superconductor, the magnetic flux penetrates the material, and the mixed state is generated. Once vortices are pinned, the superconductor can act as a magnet (known as a trapped-field magnet). In this situation, magnetism is likely influenced by the magnetic field generated by superconductivity. For example, the manipulation of local moments via superconducting vortices has been proposed using superconductor–magnet hybrids (18). To further investigate the impact of pinned vortices on the local moments, a superconductor with strong pinning properties is considered as a suitable target.The IBSs, especially the 122, 1111, and 1144 types, are known to show high critical current densities (Jc) of ∼1 MA/cm2; that is, they have a strong vortex pinning ability (1926). Based on Bean’s critical state model (27), Jc is proportional to the gradient of the magnetic flux density (μ0Jc = |dB/dx|). Then, when an IBS with a sample width (t) of 0.1 mm is magnetized in an external field, a large number of vortices are pinned and a strong magnetic field (Hsc = Jct/2) of ∼5 kOe is estimated to be generated at the center of the sample. Therefore, in the case of Eu-IBSs, the superconductivity and the magnetic subsystem are both a source of strong magnetic fields; consequently, a nontrivial situation, where the magnetic fields generated by each state mutually affect each other, is considered. In this context, EuRbFe4As4 with the highest Tc among Eu-IBSs is an optimal material to investigate the influence of superconductivity on magnetism.Fig. 1A shows the crystal structure of EuRbFe4As4. Since the Eu and Rb layers are alternately stacked without a solid solution, the Eu layer spacing is approximately twice that of EuFe2As2. Fig. 1B illustrates the temperature dependence of the magnetic susceptibility, showing a sharp superconducting transition at Tc = 37 K with perfect diamagnetism at zero-field cooling (ZFC). The kink structure at Tm = 15 K found below Tc corresponds to the magnetic ordering of the Eu2+ moments. The arrows in Fig. 1A indicate the direction of the Eu2+ moments. In the ordered state, the Eu2+ moments align ferromagnetically in the ab plane, and the orientation of the ferromagnetic alignment rotates by 90° in the next layer; that is, the ground state is a helical order (12). Meanwhile, magnetization measurements showed that the Eu2+ moments are reoriented to the ferromagnetic alignment at relatively low external fields (the saturation field [Hsat] is estimated to be ∼2 kOe) (28). In the ferromagnetically aligned state, the internal field (HEu) calculated from the Eu2+ moments (7 μB/Eu) is ∼4.5 kOe, which is approximately half of that in EuFe2As2, reflecting the Eu layer spacing.Open in a separate windowFig. 1.Crystal structure and magnetic ordering of EuRbFe4As4. (A) Crystal structure of EuRbFe4As4. Blue arrows indicate the direction of the Eu2+ moments. The schematic diagram of the helical magnetic structure is shown on the Right. (B) Temperature dependence of the magnetization of a EuRbFe4As4 single crystal measured for ZFC and field-cooling processes. A magnetic field of 10 Oe was applied along the ab plane. The Inset shows a photograph of a EuRbFe4As4 single crystal with a black scale bar corresponding to 1 mm.Thus, in EuRbFe4As4, the magnitudes of the characteristic magnetic fields related to superconductivity and magnetism, that is, Hsc, HEu, and Hsat, are comparable to each other, such that the Eu2+ moments cannot neglect the influence arising from superconductivity. In principle, it is possible to control the arrangement of local Eu2+ moments using Hsc. Moreover, because the internal field generated by superconducting currents has spatial distributions, the direction of the Eu2+ moments is expected to be locally manipulable by controlling the magnetic field profile. In this study, we demonstrate that 1) the orientation of the Eu2+ moments in magnetic fields is dominated by the direction of pinned vortices, and 2) the domain structure of the Eu2+ moments can be manipulated by the distribution of superconducting vortices.  相似文献   
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