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As the proportion of racial, ethnic, and cultural minorities in the United States continues to expand, pediatric emergency medicine providers are increasingly likely to encounter cultural and language barriers in practice. This paper reviews a conceptual framework encompassing the decision to seek emergency care, the process of providing such care, and the adherence to treatment plans and follow-up. The ways in which cultural and language barriers can negatively impact each element of this model are discussed in detail. Specific examples include provider ignorance of dangerous folk beliefs, communication barriers secondary to inappropriate interpreter use, and discriminatory assumptions regarding child abuse, pain management, and sexual activity. The practitioner is then provided with concrete recommendations to reduce these negative effects.  相似文献   
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This study examined balance ability, lower-extremity muscle strength, fear of falling and their inter-relationships in 40 community-dwelling older adults (>65 years). Subjects who self-identified either as being fearful offalling or not (no concern) were screened to exclude those with known risk factors for falling. Limits of stability, maximal isometric strength, gait speed, and fear of falling were contrasted between groups (27 control subjects, 13 fearful subjects). Those fearful of falling demonstrated smaller center of pressure (COP) excursions in anterior, left, and right directions ( p <.0001) and used a smaller percentage of their base of support during maximal weight shifting in combined anterior-posterior and right-left directions ( p <.001) compared to the control group. Strength did not differ between groups, but was associated with the ability to shift the COP in the anterior-posterior direction ( p <.05). Fear of falling also related to weight shifting ability ( p <.017). Seniors fearful of falling demonstrated limitations in balance ability and balance confidence that could not be explained by muscle weakness.  相似文献   
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OBJECTIVE

Freshly isolated pancreatic islets contain, in contrast to cultured islets, intraislet endothelial cells (ECs), which can contribute to the formation of functional blood vessels after transplantation. We have characterized how donor islet endothelial cells (DIECs) may contribute to the revascularization rate, vascular density, and endocrine graft function after transplantation of freshly isolated and cultured islets.

RESEARCH DESIGN AND METHODS

Freshly isolated and cultured islets were transplanted under the kidney capsule and into the anterior chamber of the eye. Intravital laser scanning microscopy was used to monitor the revascularization process and DIECs in intact grafts. The grafts’ metabolic function was examined by reversal of diabetes, and the ultrastructural morphology by transmission electron microscopy.

RESULTS

DIECs significantly contributed to the vasculature of fresh islet grafts, assessed up to 5 months after transplantation, but were hardly detected in cultured islet grafts. Early participation of DIECs in the revascularization process correlated with a higher revascularization rate of freshly isolated islets compared with cultured islets. However, after complete revascularization, the vascular density was similar in the two groups, and host ECs gained morphological features resembling the endogenous islet vasculature. Surprisingly, grafts originating from cultured islets reversed diabetes more rapidly than those originating from fresh islets.

CONCLUSIONS

In summary, DIECs contributed to the revascularization of fresh, but not cultured, islets by participating in early processes of vessel formation and persisting in the vasculature over long periods of time. However, the DIECs did not increase the vascular density or improve the endocrine function of the grafts.Clinical islet transplantation can restore endogenous insulin production and glycemic control in patients with type 1 diabetes, yet increased knowledge, and hence refinement, would allow for a wider application of this therapy (1). Pancreatic islets are interspersed by a dense and tortuous capillary network that facilitates an efficient exchange of oxygen, nutrients, and hormones between the endocrine cells and the bloodstream. Transplanted islets are revascularized by blood vessels that grow into the islets from the host organ via angiogenesis (2), although the acquired vasculature has a significantly lower vessel density compared with the endogenous islets (3). Furthermore, during the initial avascular engraftment period, a dramatic reduction in insulin content and high rate of cell death occur within the islets (4). Therapies that enhance the angiogenic capacity of islets by overexpression of vascular endothelial growth factor-A (VEGF-A) can increase the vascular density of islet grafts and improve metabolic function (5,6).Recently, we and others showed that donor islet endothelial cells (DIECs) can form functional vessels within transplanted islets (7,8). Immediately after isolation (i.e., in freshly isolated islets), a large number of intraislet endothelial cells (ECs) are present (79). However, if the islets are cultured, the intraislet ECs rapidly disappear, and by 4 days, only ∼5% of the initial content is detected (7). Therefore, freshly isolated islets, in contrast to cultured islets, contain an extra pool of ECs that potentially could promote islet revascularization and function after transplantation. Here, we have performed a detailed characterization of the role of DIECs in the revascularization of transplanted islets.  相似文献   
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The prevention of mother-to-child HIV transmission (PMTCT) is a complex challenge in heavily affected and resource-limited settings such as South Africa. Management of PMTCT requires a cascade of interventions that need to be addressed to effectively decrease the risk of HIV transmission to infants. This PMTCT cascade includes incremental components that can be shaped and influenced by the patient-provider relationship. The relationship that a pregnant woman has with her care providers may possibly affect decisions that she makes concerning her antenatal care and may, in turn, influence the quality of the care provided. A patient-provider relationship scale (PPRS) was developed in Pretoria, South Africa with two aims: first, to quantify the patient-provider relationship in an antenatal population in a resource-limited setting and provide preliminary evidence of its reliability and validity; and second, to determine whether the patient-provider relationship has an effect on PMTCT. The instrument was administrated in a cross-sectional pilot study to a group of women at discharge after delivery (n=192) at two major hospitals in South West Tshwane. Statistical analysis of the instrument showed high reliability (α=0.91) and preliminary evidence of its validity including significant associations with participants' attitudes regarding the functioning of the clinics and a single statement (the clinic staff "know me as a person," R=0.47, p<0.001) that has been shown previously to have a significant association with adherence to antiretroviral treatment. For HIV-positive participants, the PPRS was significantly associated with statements related to important components of the PMTCT cascade. In addition, those with substantially inadequate antenatal care (≤2 visits) and those who did not initiate highly active antiretroviral therapy, although eligible, had significantly poorer PPRS scores. The PPRS is a potentially useful, context-appropriate instrument that could have an important role in future research focused on improving PMTCT and decreasing the risk of HIV infection in children.  相似文献   
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