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71.
We aimed to define, for the first time, the ontogeny of intrarenal innervation and to assess the distribution and nature of parenchymal nerves in the human fetal kidney. Our material consisted of routinely-processed renal tissue sections from 17 human fetuses, six of 20–24 gestational weeks (gw) and 11 of 25–40 gw, and three adults. We used immunohistochemistry with antibodies to the pan-neural markers neuron-specific enolase (NSE), neurofilaments (NF), PGP9.5, S100, and the adrenergic marker tyrosine hydroxylase (TH). NSE-, NF-, S100-, and PGP9.5-positive nerves, associated with arterial and venous vasculature, were identified in the renal cortex from 20 gw onwards, and their density appeared to increase with gestation, reaching adult levels at 28 gw. Most of the intrarenal nerves were TH-positive. Nerve fibers extended from the corticomedullary region to the outer cortex, reaching the renal capsule in the 3rd trimester. In detail, NSE-, NF-, S100-, PGP9.5-, and TH-immunoreactive fibers were observed in close apposition to the renal artery and its branches, occasionally reaching the afferent and efferent arteriole (3rd trimester). Nerve fibers were detected in close apposition to the juxtaglomerular apparatus in the 2nd and 3rd trimesters. In the renal medulla, NSE-, PGP9.5-, S100-, and TH-positive nerve fibers were detected close to tubular cells as early as 20 gw. However, their density gradually decreased during the 3rd trimester, and they were not observed in the medulla of the adult kidney. In conclusion, the human fetal kidney appears richly innervated during the 2nd and 3rd trimesters. There is a progressive increase in the density of parenchymal nerve fibers towards term from the corticomedullary region to the cortex. Most intrarenal nerves are adrenergic and have a predominant perivascular distribution, implying that renal innervation plays an important functional role during intrauterine life.  相似文献   
72.
The diagnostic potential of autofluorescence (AF) microscopy under ultraviolet (UV) excitation is explored using ex vivo human specimens. The aim is to establish optical patterns (the rules for interpretation) that correspond to normal and abnormal histologies of the esophagus, spanning from early benign modifications (Barrett's esophagus) to subsequent dysplastic change and progression toward carcinoma. This was achieved by developing an image library categorized by disease progression. We considered morphological changes of disease as they are compared with histological diagnosis of the pathological specimen, as well as control samples of normal esophagus, proximal stomach, and small intestine tissue. Our experimental results indicate that UV AF microscopy could provide real-time histological information for visualizing changes in tissue microstructure that are currently undetectable using conventional endoscopic methods.  相似文献   
73.
Pompe disease is a rare autosomal recessive disorder characterized by the deficiency of acid α-glycosidase resulting in lysosomal accumulation of glycogen. The late-onset disease form is characterized by progressive skeletal and respiratory muscle dysfunction. In addition to the recently introduced enzyme replacement therapy (ERT), treatments such as protein-enriched diet and exercise training have been proposed, although little is known about their effectiveness on the physical condition of such patients. Aim of the present study was to investigate the effect of exercise training on muscular strength and body composition in five patients with late-onset Pompe disease receiving ERT. All subjects followed a 20 week lasting program of supervised aerobic and progressive resistance exercise training. Before and after the training period, body composition was determined with dual X-ray absorptiometry and isometric muscular strength was measured with a specialized load transducer. Functional capacity was assessed using the 6-min shuttle walk test. A significant increase in muscular strength (15–50% at various body parts, p < 0.05) and 6-minute walking distance (203.8 ± 177 m before vs. 248.2 ± 184 m after, p < 0.01) was observed after training, whereas total and lower extremities lean body mass did not change significantly. These results suggest that exercise training has a positive effect on muscular strength and functional capacity in patients on ERT with late-onset Pompe disease.  相似文献   
74.
Mitochondria are the bioenergetic and metabolic centers of cells and play an important role in the regulation of cell death. The mitochondrial apoptosis pathway is controlled by the bcl-2 protein family. Overexpression of mitochondrial uncoupling protein 4 (UCP4) can promote proliferation and inhibit apoptosis and differentiation. Imprint smears obtained from 124 tumors were studied immunocytochemically, and results were correlated with prognostic markers. There were 112 ductal and 12 lobular carcinomas. The positivity of UCP4 was correlated with lymph node metastases (p = 0.005), positive ER and PR expression (p < 0.0001 for both), as well as positivity for p53 (p < 0.0001) and Ki-67 (p < 0.0001). Decreased expression of bcl-2 correlated with increased expression of UCP4 (p = 0.001). Regarding DNA ploidy, UCP4 positivity was correlated with aneuploid tumors (p = 0.002). Negative expression of bcl-2 was correlated with poorly differentiated carcinomas (p < 0.0001), as well as with positive expression of p53 (p < 0.0001) and Ki-67 (p < 0.0001). Logistic regression revealed that ploidy and p53 expression had an impact on UCP4. These findings encourage future investigations regarding the potential role of UCPs not only into mechanisms underlying breast cancer, but also as a novel candidate to the design and development of more effective therapeutic strategies.  相似文献   
75.
76.
Recent advances in optical imaging for cervical cancer detection   总被引:1,自引:0,他引:1  
Cervical cancer is one of the most common and lethal gynecological malignancies in both developing and developed countries, and therefore, there is a considerable interest in early diagnosis and treatment of precancerous lesions. Although the current standard care mainly based on cytology and colposcopy has reduced rates of cervical cancer morbidity and mortality, many lesions are still missed or overcalled and referred for unnecessary biopsies. Optical imaging technologies, spectroscopy approaches and high-resolution imaging methods are anticipated to improve the conventional cervical cancer screening providing in vivo diagnosis with high sensitivity and specificity. Their concept is that morphologic and biochemical properties of the cervical tissue are altered in response to its malignant transformation. In addition, contrast agents that target against specific neoplastic biomarkers can enhance the effectiveness of this new technology. Due to the unprecedented growth of these optical techniques accompanied probably by favorable cost-effectiveness, the primary detection of premalignant lesions may become more accessible in both the developing and the developed countries and can offer see-to-treat workflows and early therapeutic interventions.  相似文献   
77.
Cellular senescence is a permanent out-of-cycle state regulated by molecular circuits acting during the G1 phase of the cell cycle. Cdt1 is a central regulator of DNA replication licensing acting during the G1 phase and it is negatively controlled by Geminin. Here, we characterize the cell cycle expression pattern of Cdt1 and Geminin during successive passages of primary fibroblasts and compare it to tumour-derived cell lines. Cdt1 and Geminin are strictly expressed in distinct subpopulations of young fibroblasts, similarly to cancer cells, with Geminin accumulating shortly after the onset of S phase. Cdt1 and Geminin are down-regulated when primary human and mouse fibroblasts undergo replicative or stress-induced senescence. RNAi-mediated Geminin knock-down in human cells enhances the appearance of phenotypic and molecular features of senescence. Mouse embryonic fibroblasts heterozygous for Geminin exhibit accelerated senescence compared to control fibroblasts. In contrast, ectopic expression of Geminin in mouse embryonic fibroblasts delays the appearance of the senescent phenotype. Taken together, our data suggest that changes in Geminin expression levels affect the establishment of senescence pathways.  相似文献   
78.
Adenovirus is isolated frequently from the amniotic fluid and has been implicated in severe neonatal infections. A case control study was carried out to examine the association of detection of adenovirus in placentas with preterm birth and histological chorioamnionitis. Placentas from preterm and full term deliveries were collected prospectively. Preterm cases were divided into three subgroups according to the gestational age. PCR was carried out on placental tissues for the detection of adenovirus genome. Placentas were evaluated histologically for the presence of chorioamnionitis. Chi‐square and odds ratios (OR) were used to determine if detection of adenovirus is associated with preterm birth and histological evidence of inflammation. Seventy‐one preterm and 122 full term placentas were studied. Adenovirus genome was detected in 29 (40.8%) of preterm cases and in 25 (20.5%) of the full term controls (OR = 2.6; 95% CI, 1.4–5.1; P = 0.002). Detection of adenovirus in preterm placentas was significantly higher compared to full term particularly in the lower gestational age. Detection of adenovirus in placenta followed the seasonal variation of adenovirus infections. Thirty‐seven preterm and 21 full term placentas were also selected for paraffin inclusion and histological examination. Chorioamnionitis was present more frequently in preterm adenovirus‐positive placentas compared to preterm adenovirus‐negative placentas (75% vs. 36%; P = 0.026) as well as compared to term adenovirus‐positive placentas (75% vs. 19%; P = 0.003). This study demonstrates that adenovirus infection of the placenta is associated strongly with histological chorioamnionitis and preterm birth. J. Med. Virol. 82:1379–1383, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
79.
80.
There is a strong association between serum antibody responses to toxin A and protection against Clostridium difficile diarrhea. A parenteral C. difficile toxoid vaccine induced very-high-level responses to anti-toxin A immunoglobulin G (IgG) in the sera of healthy volunteers. After vaccination, the concentrations of anti-toxin A IgG in the sera of all 30 recipients exceeded the concentrations that were associated with protection in previous clinical studies. Furthermore, the median concentration of serum anti-toxin A IgG in the test group was 50-fold higher than the previous threshold. These findings support the feasibility of using a vaccine to protect high-risk individuals against C. difficile-associated diarrhea and colitis.  相似文献   
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