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91.
Uromucoid in normal urine   总被引:1,自引:0,他引:1  
Uromucoid was determined in urine from persons or various ages with normal kidney function by a radial immunodiffusion technique. Uromucoid concentration was inversely correlated to diuresis. Excretion rates showed a weak correlation to body surface area in young adults of both sexes. Children had a greater excretion of uromucoid per m2 than young adults, and even newborn had a considerable excretion. Elderly subjects had similar excretion rates to young adults. Excretion rates were uninfluenced by sex, salt load or diuresis, and no difference between day and night excretion rates was observed. Intraindividual fluctuations were small, and determination of uromucoid in one single night's urine therefore gives an adequate expression of the uromucoid excretion rate.  相似文献   
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93.
While female mice do not have the equivalent of a menopause, they do undergo reproductive senescence. Thus, to dissociate the effects of aging versus estrogen deficiency on age‐related bone loss, we sham‐operated, ovariectomized, or ovariectomized and estrogen‐replaced female C57/BL6 mice at 6 months of age and followed them to age 18 to 22 months. Lumbar spines and femurs were excised for analysis, and bone marrow hematopoietic lineage negative (lin–) cells (enriched for osteoprogenitor cells) were isolated for gene expression studies. Six‐month‐old intact control mice were euthanized to define baseline parameters. Compared with young mice, aged/sham‐operated mice had a 42% reduction in lumbar spine bone volume/total volume (BV/TV), and maintaining constant estrogen levels over life in ovariectomized/estrogen‐treated mice did not prevent age‐related trabecular bone loss at this site. By contrast, lifelong estrogen treatment of ovariectomized mice completely prevented the age‐related reduction in cortical volumetric bone mineral density (vBMD) and thickness at the tibial diaphysis present in the aged/sham‐operated mice. As compared with cells from young mice, lin– cells from aged/sham‐operated mice expressed significantly higher mRNA levels for osteoblast differentiation and proliferation marker genes. These data thus demonstrate that, in mice, age‐related loss of cortical bone in the appendicular skeleton, but not loss of trabecular bone in the spine, can be prevented by maintaining constant estrogen levels over life. The observed increase in osteoblastic differentiation and proliferation marker gene expression in progenitor bone marrow cells from aged versus young mice may represent a compensatory mechanism in response to ongoing bone loss. © 2010 American Society for Bone and Mineral Research.  相似文献   
94.
Background: Blood flow imaging is a new ultrasound modality that supplements color Doppler imaging with angle‐independent information of flow direction that is not influenced by velocity aliasing. This is done by visualizing the blood speckle movement superimposed on the color Doppler images. This study aimed to investigate whether this method improves the visualization of the pulmonary veins in neonates. Methods: Twenty‐six neonates with suspected congenital heart disease were prospectively examined with echocardiography and blood flow imaging of the pulmonary veins after parental consent. For each patient, blood flow imaging and color Doppler imaging cine loops were presented to four observers (pediatric cardiologist/cardiologists) in a random order. Questions regarding the pulmonary venous connections and the overall quality of the pulmonary vein imaging were evaluated on a visual analogue scale from 0 (worst) to 100 (best). The methods were compared within each observer using the Wilcoxon's exact signed‐rank test. Results: Blood flow imaging (color Doppler imaging combined with the blood speckle movement) was consistently ranked as better than conventional color Doppler imaging for visualization of the pulmonary veins for all observers (all P‐values < 0.002). Conclusion: Blood flow imaging may improve the visualization of the pulmonary veins in neonates. (Echocardiography 2010;27:1113‐1119)  相似文献   
95.
BACKGROUND: The well-known immune deficiency of the chronic alcoholic dictates the need for a long-term rodent ethanol administration model to evaluate the baseline immunologic effects of chronic ethanol abuse, and investigate the genetic determinants of those effects. Much published work with rodents has shown clearly that acute ethanol administration and short-term ethanol-containing liquid diets both cause elevated corticosterone and can cause significant thymocyte, pre-B cell and peripheral lymphocyte losses. Such losses may mask more subtle alterations in immune homeostasis, and in any case are generally short-lived compared with the span of chronic ethanol abuse. Thus, it is important to have a model in which long-term immune alterations can be studied free of corticosteroid-induced cell losses. METHODS: We have utilized chronic 20% (w/v) ethanol in water administration to several mouse strains for prolonged periods of time and evaluated serum corticosterone, immunologic stress parameters, and other organ changes by standard methods. RESULTS: We now confirm earlier reports that chronic ethanol in water administration to mice does not produce net elevations of corticosterone, although diurnal variation is altered. Importantly, there is neither selective loss of immune cell populations known to be corticosteroid sensitive, CD4+CD8+ thymocytes and pre-B cells, nor are changes observed in the histologic appearance of the thymus. Nonetheless, there are significant chronic ethanol effects in other tissues, including reduced heart weight, mild hepatic steatosis, alterations of gut flora, increased serum peptidoglycan, and as published elsewhere, immune system abnormalities. CONCLUSIONS: This model of ethanol administration is convenient, sustainable for up to 1 year, demonstrably feasible in several mouse strains, permits good weight gains in most strains, and results in significant changes in a number of organs. The administration method also will permit modeling of long-term steady abuse punctuated by major binges, and is suitable for supplementation studies using water soluble additives. Overall, the method is useful for a wide range of studies requiring a chronic low-stress method of ethanol administration.  相似文献   
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97.
PURPOSE: To investigate the effects of training intensity and duration, through a range representative of training in endurance athletes, on acute recovery of autonomic nervous system (ANS) balance after exercise. METHODS: Nine highly trained (HT) male runners (VO2max 72 +/- 5 mL.kg.min(-1), 14 +/- 3 training hours per week) and eight trained (T) male subjects (VO2max 60 +/- 5 mL.kg.min(-1), 7 +/- 1 training hours per week) completed preliminary testing to determine ventilatory thresholds (VT1, VT2) and VO2max. HT performed four intensity-controlled training sessions: 60 min and 120 min below VT1; 60 min with 30 min between VT1 and VT2 (threshold); and 60 min above VT2 (6 x 3 min at 96% VO2max, 2 min of recovery). T also completed the interval session to compare ANS recovery between HT and T. Supine heart rate variability (HRV) was quantified at regular intervals through 4 h of recovery. RESULTS: When HT ran 60 or 120 min below VT1, HRV returned to pretraining values within 5-10 min. However, training at threshold (2.7 +/- 0.4 mM) or above VT2 (7.1 +/- 0.7 mM) induced a significant, but essentially identical, delay of HRV recovery (return to baseline by approximately 30 min). In T, HRV recovery was significantly slower, with HRV returning to baseline by >or=90 min after the same interval session. CONCLUSIONS: In the highly trained endurance athlete, exercise for 相似文献   
98.
Psoriasis is a common chronic skin disease with a largely unknown pathogenesis. We demonstrate here that transgenic over-expression of interleukin (IL)-22 in mice resulted in neonatal mortality and psoriasis-like skin alterations including acanthosis and hypogranularity. This cutaneous phenotype may be caused by the direct influence of IL-22 on keratinocytes, since this cytokine did not affect skin fibroblasts, endothelial cells, melanocytes, or adipocytes. The comparison of cytokines with hypothesized roles in psoriasis pathogenesis determined that neither interferon (IFN)-γ nor IL-17, but only IL-22 and, with lower potency, IL-20 caused psoriasis-like morphological changes in a three-dimensional human epidermis model. These changes were associated with inhibited keratinocyte terminal differentiation and with STAT3 upregulation. The IL-22 effect on differentiation-regulating genes was STAT3-dependent. In contrast to IL-22 and IL-20, IFN-γ and IL-17 strongly induced T-cell and neutrophilic granulocyte-attracting chemokines, respectively. Tumor necrosis factor-α potently induced diverse chemokines and additionally enhanced the expression of IL-22 receptor pathway elements and amplified some IL-22 effects. This study suggests that different cytokines are players in the psoriasis pathogenesis although only the IL-10 family members IL-22 and IL-20 directly cause the characteristic epidermal alterations. Kerstin Wolk and Harald S. Haugen equally contributed to this work.  相似文献   
99.
Objectives: To examine the provision of support to patients with frontotemporal dementia (FTD) and their family carers compared with patients with early onset Alzheimer's dementia (AD) and their carers, and the carers' satisfaction with the support. Method: Data came from 60 dyads of patients with dementia and their principal family carers, 23 subjects with frontotemporal dementia and their 23 carers, and 37 subjects with early onset Alzheimer's disease and their 37 carers. Results: Patients with a frontotemporal dementia diagnosis were significantly more frequently offered stays in nursing homes (p = 0.04). Carers of patients with frontotemporal dementia were significantly less satisfied with the provision of information about the disease compared with carers of early onset Alzheimer's disease patients (p = 0.05) and were significantly less satisfied with counseling and follow-up advice (p = 0.05). Conclusion: Changes of personality in patients with frontotemporal dementia may be the major reason why they were offered more stays in institutions. These family carers tend to be less satisfied with the provision of support they received from the specialist health service compared to carers of Alzheimer's disease patients, and are in need of more, and other forms of support.  相似文献   
100.
It is well known that men with testicular cancer also have reduced fertility before diagnosis. It is unclear, however, whether their parents also have reduced fertility. We performed a population-based record linkage study comparing parental fertility among 3711 testicular cancer cases and 371 100 control males. The cases were diagnosed from 1961 to 2001, and the data were analysed by logistic regression. Included indicators of parental fertility were number of children, rate of unlike-sex twins as a proxy for dizygotic twinning rate, and proportion of boys. The number of children was reduced across increasing sibship size among both mothers [odds ratio (OR) = 0.95, p(trend) = 0.003] and fathers [OR = 0.97, p(trend) = 0.057] of subjects with testicular cancer. The proportion of unlike-sex twins was also reduced among their mothers [(OR = 0.56, p = 0.049 (adjusted for year of birth)] and fathers [(OR = 0.56, p = 0.049 (adjusted for year of birth)]. The results were only marginally changed when also adjusting for respective parental age. Our study indicates that parents of testicular cancer cases have reduced fertility. This suggests that genetic factors are important in the association between testicular cancer and reduced fertility.  相似文献   
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