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31.
Nonalcoholic steatohepatitis is related to lifestyle, particularly to dietary habits. We developed diet-induced fibrotic steatohepatitis model stroke-prone spontaneously hypertensive 5/Dmcr (SHRSP5/Dmcr) rats showing steatosis, hepatic inflammation, and severe fibrosis induced by high-fat and -cholesterol (HFC) diet feeding. We aimed to clarify the efficacy of dietary intervention on the disease before and after the appearance of fibrosis. Male SHRSP5/Dmcr rats were divided into 9 groups; of these, 6 groups were fed control or HFC diet for several weeks and the remaining 3 groups represented the dietary intervention groups, which were fed the control diet after HFC diet feeding for 2 (before the appearance of fibrosis) or 8 (after the appearance of fibrosis) weeks. Dietary intervention before the appearance of fibrosis significantly improved the steatosis and reset the increased serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and serum total cholesterol (TC) levels. However, dietary intervention after the appearance of fibrosis was unable to reset the levels of hepatic TC, serum ALT, and fibrogenesis-related markers and had only a minor influence on hepatic fibrosis, although it reset the increased expression of transforming growth factor (TGF)-β1 and α-smooth muscle actin (SMA). It was noted that dietary intervention improved the increased AST levels; however, aggregated CD68-positive cells were still observed around the fibrosis area, which may be related to the findings of inflammatory cytokine mRNAs. Taken together, dietary intervention for fibrotic steatohepatitis improved steatosis, although it could not completely improve fibrosis.  相似文献   
32.
Tubular injury is one of the important determinants of progressive renal failure in diabetic nephropathy (DN), and TGF-β1 has been implicated in the pathogenesis of tubulointerstitial disease that characterizes proteinuric renal disease. The aim of this study was to identify novel therapeutic target molecules that play a role in the tubule damage of DN. We used an LC-MS/MS-based proteomic technique and human renal proximal epithelial cells (HRPTECs). Urine samples from Japanese patients with type 2 diabetes (n = 46) were used to quantify the candidate protein. Several proteins in HRPTECs in cultured media were observed to be driven by TGF-β1, one of which was 33-kDa IGFBP7, which is a member of IGFBP family. TGF-β1 up-regulated the expressions of IGFBP7 mRNA and protein in a dose- and time-dependent fashion via Smad2 and 4, but not MAPK pathways in HRPTECs. In addition, the knockdown of IGFBP7 restored the TGF-β1-induced epithelial to mesenchymal transition (EMT). In the immunohistochemical analysis, IGFBP7 was localized to the cytoplasm of tubular cells but not that of glomerular cells in diabetic kidney. Urinary IGFBP7 levels were significantly higher in the patients with macroalbuminuria and were correlated with age (r = 0.308, p = 0.037), eGFR (r = −0.376, p = 0.01), urinary β2-microglobulin (r = 0.385, p = 0.008), and urinary N-acetyl-beta-D-glucosaminidase (NAG) (r = 0.502, p = 0.000). A multivariate regression analysis identified urinary NAG and age as determinants associated with urinary IGFBP7 levels. In conclusion, our data suggest that TGF-β1 enhances IGFBP7 via Smad2/4 pathways, and that IGFBP7 might be involved in the TGF-β1-induced tubular injury in DN.  相似文献   
33.
34.
Species of fleshy yellow Cantharellus are known as chanterelles, which are among the most popular wild edible mycorrhizal mushrooms in the world. However, pure culture isolates of Cantharellus are rare. We report an efficient isolation technique of the Japanese golden chanterelle, Cantharellus anzutake, from its ectomycorrhizal root tips. Field-sampled fresh ectomycorrhizal root tips of C. anzutake on various hosts such as pines, spruce, and oaks were vortexed with 0.005% Tween 80 solution, surface sterilized with 1% calcium hypochlorite solution, rinsed with sterilized distilled water, and placed on modified Norkrans’ C (MNC) agar plate medium. Most ectomycorrhizal root tips of C. anzutake produced yellowish mycelial colonies within a few months. In contrast, tissue isolation from basidiomata provided limited cultures of C. anzutake but much contamination of bacteria and molds, even on media that contained antibiotics. The established C. anzutake cultures had clamp connections on the hyphae and contained intracellular oily droplets. These cultured isolates were identified as C. anzutake by sequence analysis of the rRNA internal transcribed spacer (ITS) region and translation elongation factor EF1-alpha (tef-1) genes.  相似文献   
35.
The objective of this study was to develop an ideal freezing extender and method for rat epididymal sperm cryopreservation. Epididymal sperm collected from 30 Wistar males was frozen, and experiments were conducted to study its post-thaw characteristics when freezing with raffinose-free buffer or various concentrations of raffinose and egg yolk dissolved in distilled and deionised water, PBS, or modified Krebs–Ringer bicarbonate (mKRB)-based extender. Different concentrations of glycerol, Equex STM, or sodium dodecyl sulfate (SDS) dissolved in either PBS or mKRB containing egg yolk were also tested. Based on the data from these experiments, further experiments tested how different sugars such as raffinose, trehalose, lactose, fructose, and glucose dissolved in mKRB with Equex STM, SDS and egg yolk supplementation affected the post-thaw characteristics of cryopreserved sperm. Cryosurvival of frozen-thawed sperm were judged by microscopic assessment of the sperm motility index (SMI), and acrosome integrity was measured using FITC-PNA staining. Thawed sperm were subjected to 3 h of a thermal resistance test. Beneficial effects on the post-thaw survival of sperm were obtained when 0.1 M raffinose in mKRB was used with 0.75% Equex STM, 0.05% SDS, and 20% egg yolk. Sperm cryopreserved with this treatment exhibited a higher motility index and maintained greater SMI and acrosome integrity throughout incubation when compared to sperm frozen in various concentrations of other cryoprotectants and trehalose, lactose, fructose, glucose. In conclusion, cryopreservation in an extender solution of raffinose dissolved in mKRB containing Equex STM, SDS and egg yolk greatly enhances the freezability of rat epididymal sperm.  相似文献   
36.
In this study we examined the effect of the specific gravity of culture medium on the frequency of hematopoietic stem cell (HSC) maintenance. We used a newly developed high-specific-gravity media. Bone marrow cells were isolated and cultured, and HSC activity was evaluated. The number of hematopoietic progenitor/stem cells was markedly higher in the medium with high specific gravity. In high-specific-gravity media, cells did not precipitate, maintenance of HSCs was increased, and there was a concomitant accumulation of beta-catenin. This novel technique for maintaining HSC populations provides an important new tool for studies in regenerative medicine.  相似文献   
37.
Bone marrow development and endochondral bone formation occur simultaneously. During endochondral ossification, periosteal vasculatures and stromal progenitors invade the primary avascular cartilaginous anlage, which induces primitive marrow development. We previously determined that bone marrow podoplanin (PDPN)-expressing stromal cells exist in the perivascular microenvironment and promote megakaryopoiesis and erythropoiesis. In this study, we aimed to examine the involvement of PDPN-expressing stromal cells in postnatal bone marrow generation. Using histological analysis, we observed that periosteum-derived PDPN-expressing stromal cells infiltrated the cartilaginous anlage of the postnatal epiphysis and populated on the primitive vasculature of secondary ossification center. Furthermore, immunophenotyping and cellular characteristic analyses indicated that the PDPN-expressing stromal cells constituted a subpopulation of the skeletal stem cell lineage. In vitro xenovascular model cocultured with human umbilical vein endothelial cells and PDPN-expressing skeletal stem cell progenies showed that PDPN-expressing stromal cells maintained vascular integrity via the release of angiogenic factors and vascular basement membrane-related extracellular matrices. We show that in this process, Notch signal activation committed the PDPN-expressing stromal cells into a dominant state with basement membrane-related extracellular matrices, especially type IV collagens. Our findings suggest that the PDPN-expressing stromal cells regulate the integrity of the primitive vasculatures in the epiphyseal nascent marrow. To the best of our knowledge, this is the first study to comprehensively examine how PDPN-expressing stromal cells contribute to marrow development and homeostasis.  相似文献   
38.
One-hundred and thirteen Candida albicans strains isolated from patients infected by the human immunodeficiency virus (HIV) and twenty five from HIV-negative individuals were studied. The C. albicans strains isolated from different sites of the body were tested for germ-tube (GT), phospholipase production and serotype. The results obtained indicate that the serotype A was predominant in all the groups except for the vaginal strains. No correlation was observed between phospholipase activity and serotype distribution. Germ tube (GT) production was higher among the serotype B strains. A positive correlation between GT induction and phospholipase activity was observed only for the isolates from the oral cavity. It is possible that the correlation between phospholipase activity and high GT production in C. albicans strains can facilitate the penetration through the mucosa.  相似文献   
39.
It is known that a large quantity of magnesium contains bones, and the magnesium contents in spongy bones decrease gradually with advancing age. To elucidate the relationships between a decrease of mineral contents in human bones and an accumulation of minerals in the other human tissues, the content of magnesium was analyzed by inductively coupled plasma-atomic emission spectrometry among human bones, arteries, veins, and cartilages in 27 subjects (17 men and 10 women). These were resected from the subjects who died in the age range 40–98 yr. Calcanei were chosen for analysis of magnesium contents in contrast with femoral, popliteal, and common carotid arteries, internal jugular and femoral veins, superior and inferior venae cavae, and pubic symphyses. The magnesium contents in the calcanei decreased gradually with aging, whereas they increased progressively in the arteries, veins, and pubic symphyses with aging. It was found that as the magnesium contents decreased in the calcanei, they increased in the arteries, such as the femoral, popliteal, and common carotid arteries, whereas they decreased inversely in the veins, such as the internal jugular and femoral veins and superior and inferior venae cavae. Furthermore, as the magnesium contents decreased in the calcanei, they hardly changed in the pubic symphyses. These suggest that magnesium released from bones is accompanied by accumulation of magnesium in the arteries.  相似文献   
40.
On age relationships of mineral contents in human bones, the contents of the sixth rib and a piece of its compact bone were determined by inductively coupled plasma atomic emission spectrometry (ICPS). The ribs were resected from 21 subjects (14 men and 7 women) who died in age ranging from 65 to 93 yr. There were no age-dependent decreases in Ca and P contents of the ribs in the age range on ICPS. It was found that there were no age-dependent decreases in Ca and P in compact bones of ribs.  相似文献   
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