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971.
972.
BACKGROUND: Pulse oximetry is a frequently used, noninvasive monitoring tool for assessing arterial blood oxygenation. Physicians, registered nurses, and respiratory therapists are responsible for the accurate interpretation of pulse oximetry data as part of the evaluation and management of acutely and critically ill patients. OBJECTIVES: (1) To evaluate the extent of current knowledge about pulse oximetry and (2) to increase clinicians' knowledge of research-based practices related to the appropriate use of pulse oximetry and interpretation of its results. METHODS: A test/survey of 17 true-false questions based on the research-based practice protocol of the American Association of Critical-Care Nurses was developed to evaluate current knowledge of pulse oximetry. A convenience sample of medical, nursing, and respiratory therapy staff was invited to complete the test/survey before and several months after an educational program to improve staff members' knowledge of pulse oximetry. The program included educational forums, policy changes, competency checklists, and verification of inclusion of research-based principles in orientation programs. RESULTS: A total of 442 staff members completed the test/survey given before the educational program: 331 nurses, 82 physicians, and 29 respiratory therapists. The overall mean percentage of correct answers was 66%. Differences between disciplines were significant: respiratory therapists scored slightly higher (76%) than did nurses (64%) and physicians (66%) (P = .01). The scores on the test/survey given after the educational program increased significantly, from 66% to 82% (P < .01). CONCLUSIONS: This educational project improved staff members' knowledge of pulse oximetry monitoring.  相似文献   
973.
The aim of the present study is to define the temporal relationships of the IgM and IgG responses to Streptococcal group A carbohydrate (CHO) in rabbits and in man. Rabbits were immunized with group A streptococci and the development of anti-group A carbohydrate (ACHO) was studied. ACHO which appeared one week after the beginning of immunization belonged to the 19S class of immunoglobulins (IgM). A two- to four-fold rise in ACHO titers and immunoglobulins of the 7S class (IgG) were observed after two weeks. Three weeks after the beginning of immunization, the ACHO titer was at a maximum. In the following months no further rises in titer were seen, and the antibodies belonged mostly to the IgG class. IgM and IgG responses to streptococcal CHO and to extracellular antigens in patients with pharyngitis, acute rheumatic fever (ARF), and acute glomerulonephritis (AGN) were studied. Higher values of IgM were found in pharyngitis and AGN sera than in ARF sera, probably reflecting the interval between streprococcal infection and time of bleeding. ACHO antibodies persisted in patients' sera for long periods and belonged to IgG and IgM. This suggests a continuous, rather than a persistent, production of ACHO.  相似文献   
974.
975.
976.
The thymic cortex provides a microenvironment for the development and positive selection of immature T cells. Cortical thymic epithelial cells (cTECs), which structurally and functionally support the thymic cortical microenvironment, originate from endodermal epithelial progenitors that arise in the third pharyngeal pouch. Recent studies have revealed that thymic epithelial progenitors pass through a stage where the cells express cTEC-associated molecules prior to lineage separation into cTECs and medullary TECs (mTECs). Here, we review the molecular signatures of cTECs and highlight the development and developmental potential of cTECs.  相似文献   
977.
PurposeJapanese hop (Humulus spp.) and mugwort (Artemisia spp.) are notable causes of autumn pollinosis in East Asia. However, Japanese hop and mugwort pollen extracts, which are widely used for the diagnosis, have not been standardized. This study was performed to standardize Japanese hop and mugwort pollen extracts.ResultsThe IgE reactive components of the extracts via IgE immunoblotting were similar to those of commercial extracts. A 11-kDa allergen showed the strongest IgE reactivity in Japanese hop, as did a 28-kDa allergen in mugwort pollen extracts. Allergenic potencies of the investigatory Japanese hop and mugwort extracts were essentially indistinguishable from the commercial ones. Sums of erythema of 50 mm by the intradermal skin test (ΣED50) were calculated to be 14.4th and 13.6th three-fold dilutions for Japanese hop and mugwort extracts, respectively. Therefore, the allergenic activity of the prepared extracts was 90827.4 BAU/mg for Japanese hop and 34412 BAU/mg for mugwort.ConclusionWe produced Japanese hop and mugwort pollen extracts using a standardized method. Standardized Japanese hop and mugwort pollen extracts will facilitate the production of improved diagnostic and immunotherapeutic reagents.  相似文献   
978.
Our objective is to evaluate the relationships between prenatal maternal stress and depressive symptoms, respectively, and infant neurodevelopment at 6 months, adjusted for heavy metals and oxidative stress. This research is a part of a multi-center birth cohort study in South Korea. Information on stress and depressive symptoms was collected during the first trimester using Psychosocial Well-Being Index Short Form (PWI-SF) and Center for Epidemiological Studies Depression Scale (CES-D). The Korean Bayley Scales of Infant Development-II assessment (BSID-II), which includes the standardized mental development index (MDI) and psychomotor developmental index (PDI), and Korean Ages & Stages Questionnaires (K-ASQ) were applied to infants at six months of age. A higher index score indicates better development. Among 641 babies, 320 were female (50%). Maternal PWI ≥ 29 (vs. PWI ≤ 18) during early pregnancy was associated with a decrease in MDI scores of 5.37 points (P = 0.02) after adjusting for socioeconomic factors. Maternal CES-D ≥ 26 (vs. CES-D ≤ 10) during early pregnancy was associated with a decrease in MDI scores of 8.18 points (P = 0.01). The associations remained significant even after adjustment for lead, cadmium, and MDA levels (P < 0.05). However, no association was found between maternal PWI/CES-D and PDI score. No interaction was observed between stress and lead exposure. We found an inverse association between prenatal maternal stress and depressive symptoms, and MDI scores in 6-month-old infants after adjustment for prenatal lead exposure, which is known to affect cognitive function negatively.  相似文献   
979.
This study examined whether dietary supplementation can be used to protect against ischemic stroke. Two groups of adult male Sprague-Dawley rats initially received NT-020, a proprietary formulation of blueberry, green tea, Vitamin D3, and carnosine (n = 8), or vehicle (n = 7). Dosing for NT-020 and vehicle consisted of daily oral administration (using a gavage) over a 2-week period. On day 14 following the last drug treatment, all animals underwent the stroke surgery using the transient 1-hour suture occlusion of middle cerebral artery (MCAo). To reveal the functional effects of NT-020, animals were subjected to established behavioral tests just prior to stroke surgery and again on day 14 post-stroke. ANOVA revealed significant treatment effects (p < 0.05), characterized by reductions of 11.8% and 24.4% in motor asymmetry and neurologic dysfunction, respectively, in NT-020-treated stroke animals compared to vehicle-treated stroke animals. Evaluation of cerebral infarction revealed a significant 75% decrement in mean glial scar area in the ischemic striatum of NT-020-treated stroke animals compared to that of vehicle-treated stroke animals (p < 0.0005). Quantitative analysis of subventricular zone's cell proliferative activity revealed at least a one-fold increment in the number of BrdU-positive cells in the NT-020-treated stroke brains compared to vehicle-treated stroke brains (p < 0.0005). Similarly, quantitative analysis of BrdU labeling in the ischemic striatal penumbra revealed at least a three-fold increase in the number of BrdU-positive cells in the NT-020-treated stroke brains compared to vehicle-treated stroke brains (p < 0.0001). In addition, widespread double labeling of cells with BrdU and doublecortin was detected in NT-020-treated stroke brains (intact side 17% and ischemic side 75%), which was significantly higher than those seen in vehicle-treated stroke brains (intact side 5% and ischemic side 13%) (p < 0.05). In contrast, only a small number of cells in NT-020-treated stroke brains double labeled with BrdU and GFAP (intact side 1% and ischemic side 2%), which was significantly lower than those vehicle-treated stroke brains (intact side 18% and ischemic side 35%) (p < 0.0001). Endogenous neurogenic factors were also significantly upregulated in the ischemic brains of NT-020-treated stroke animals. These data demonstrate the remarkable neuroprotective effects of NT-020 when given prior to stroke, possibly acting via its neurogenic potential.  相似文献   
980.
Urocortins, a novel member of the corticotrophin-releasing factor (CRF) family, have been shown in animal and human studies to possess several beneficial effects in stress, cardiovascular and renal function, and inflammatory responses via CRF receptors. In the heart, urocortins have been demonstrated to produce cardioprotective effects during ischemia and reperfusion injury. Urocortins have also exerted effects on hemodynamic, endocrine and renal parameters in experimental animal heart failure models. In humans, plasma urocortin levels have been shown to significantly increase in systolic heart failure patients. This growing evidence suggests that urocortins may have a prognostic value as well as being a potential therapeutic treatment for heart failure and myocardial infarction patients. Currently, only a few clinical studies on urocortins are available. In this review article, the role of urocortins in the heart has been summarized. Their possible beneficial roles in heart failure and myocardial infarction have been discussed, based on relevant published articles from both basic and clinical studies available to date.  相似文献   
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