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61.
Diffuse alveolar damage is the histopathologic hallmark of acute respiratory distress syndrome (ARDS). A significant proportion of ARDS survivors have residual pulmonary fibrosis and compromised pulmonary function. On the other hand, heat shock protein 47 (HSP47) is a collagen-binding stress protein that is assumed to act as a collagen-specific molecular chaperone during the biosynthesis and secretion of procollagen in living cells. The synthesis of HSP47 has been reported to correlate with that of collagen in several cell lines. We examined the expression of HSP47 mRNA and protein during the progression of lipopolysaccharide (LPS)-induced ARDS in rat lung. Male Wistar rats were randomly divided into two groups: a control group with instillation of 0.9% NaCl solution alone, and a LPS group with instillation of LPS dissolved in 0.9% NaCl solution (10 mg/kg). Histologic changes thereafter appeared in the LPS-treated rats. Northern blot analysis revealed the expression of HSP47 mRNA to be markedly induced during the progression of lung damage in parallel with type I and type III collagen mRNA. These results suggest that the upregulation of HSP47 and collagen may play an important role in the fibrotic process of LPS-induced ARDS lung.  相似文献   
62.
Nifedipine, a dihydropyridine calcium antagonist, improves endothelial function in patients with hypercholesterolaemia by enhancing nitric oxide (NO) activity, and increases endothelial NO bioavailability by antioxidant mechanisms. We administered a long-acting nifedipine formulation (controlled release (CR) nifedipine: 20 mg/day) to hypertensive patients for 6 months. There were no other changes of drug treatment during therapy with CR nifedipine. Clinical and biochemical data obtained before and after CR nifedipine administration were compared. All markers were measured by enzyme-linked immunosorbant assay. The levels of soluble markers (soluble CD40 ligand, soluble P-selectin, and soluble E-selectin), microparticles (MP) (platelet-derived MP, monocyte-derived MP, and endothelial cell-derived MP), and adiponectin differed between the control group and the hypertension group. The levels of these markers were also different in hypertensive patients with and without type 2 diabetes compared with the control group. In the hypertensive patients with type 2 diabetes, all markers except adiponectin decreased significantly after 3 months of CR nifedipine treatment. In contrast, markers were unchanged in the hypertensive patients without type 2 diabetes. Adiponectin was increased after 6 months of CR nifedipine treatment in hypertensive patients with type 2 diabetes. The effects of CR nifedipine on platelet/monocyte activation and adiponectin levels demonstrated in the present study indicate the potential effectiveness of calcium antagonist therapy for hypertensive patients with type 2 diabetes.  相似文献   
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64.
The aim of this study was to determine whether pitavastatin may prevent the progression of atherosclerotic changes in hyperlipidemic patients. Seventy-five hyperlipidemic patients with and without type 2 diabetes were enrolled to receive pitavastatin 2 mg daily. Cell adhesion molecules (sCD40L, sP-selectin, sE-selectin, and sL-selectin), chemokines (MCP-1 and RANTES) and adiponectin were measured at baseline and after 3 and 6 months of pitavastatin treatment. Adiponectin levels prior to pitavastatin treatment in hyperlipidemic patients with and without diabetes were lower than levels in normolipidemic controls. Both total cholesterol and the LDL-cholesterol (LDL-C) decreased significantly after pitavastatin administration. Additionally, hyperlipidemic patients with type 2 diabetes exhibited a significant increase in adiponectin levels after pitavastatin treatment (before vs. 3 months, 6 months, 2.81 ± 0.95 vs. 3.84 ± 0.84 μg/ml (p < 0.01), 4.61 ± 1.15 μg/ml (p < 0.001)). Furthermore, hyperlipidemic diabetics exhibited significant decreases in sE-selectin and sL-selectin levels after 6 months of pitavastatin treatment (sE-selectin, before vs. 6 months, 74 ± 21 vs. 51 ± 10 ng/ml, p < 0.05; sL-selectin, before vs. 6 months, 896 ± 141 vs. 814 ± 129 ng/ml, p < 0.05). In addition, adiponectin showed significant correlation with sE-selectin and sL-selectin in diabetic hyperlipidemia. However, MCP-1, RANTES and sCD40L did not exhibit any differences before or after pitavastatin administration. These results suggest that pitavastatin possesses an adiponectin-dependent anti-atherosclerotic effect in hyperlipidemic patients with type 2 diabetes in addition to its lowering effects on total cholesterol and LDL-C.  相似文献   
65.
A hepatectomy is the only treatment offering long-term survival in patients with colorectal liver metastases. However, 70-80% of the patients with a complete resection develop recurrent disease after an initial hepatectomy. Sixty-one patients who underwent metastases from colorectal carcinoma with a curative hepatectomy were entered into this study. Recurrence after hepatectomy was observed in 41 patients (67.2%). We reviewed the outcome of these 41 patients. Repeat reduction surgery was performed on 16 out of 41 patients (39.0%). According to a multivariate analysis, repeat reduction surgery and tumor size were found to be independent prognostic factors for the survival rate (p=0.007, p=0.018). Furthermore, in the group that underwent repeat reduction surgery, the rate of positive lymph nodes was significantly lower in the primary lesions, and the disease-free interval (DFI) was also significantly longer than in the group that did not undergo repeat reduction surgery (p=0.023, p=0.045), respectively. Repeat reduction surgery was found to be the most important prognostic factor. Patients with a longer DFI and with negative lymph node findings at the primary site may therefore be considered to be good candidates for repeat reduction surgery.  相似文献   
66.
The most common cause of death from poisoning by the widely used, but highly toxic herbicide paraquat is respiratory failure from pulmonary fibrosis, which develops through pathological overproduction of extracellular matrix proteins such as the collagens. Heat shock protein (HSP47) is a collagen-specific molecular chaperone that assists in the posttranslational modifications of procollagens during collagen biosynthesis. We investigated whether treatment with an HSP47-antisense oligonucleotide would inhibit paraquat-induced pulmonary fibrosis in Wistar rats. Rats randomized into three groups (control, paraquat, and paraquat+antisense). Paraquat (20 mg/kg/day) (n=16) or a saline control (n=10) was administered to groups of Wistar rats. Intratracheal administration of the antisense oligonucleotide (100 nmol/kg in saline) was performed after the initial paraquat treatment (n=16). Treatment with paraquat alone induced pulmonary fibrosis in the entire group, while treatment with the antisense oligonucleotide alone did not produce any substantial change in lung histology. Administration of antisense oligonucleotides produced a substantial reduction in paraquat-induced pulmonary fibrosis. An immunoblot analysis confirmed that the HSP47-antisense oligonucleotide inhibited HSP47 production. These findings indicate that the HSP47-antisense oligonucleotide inhibited paraquat-induced pulmonary fibrosis and pneumopathy in rats.  相似文献   
67.
The present study examined whether total enteral nutrition (TEN) and total parenteral nutrition (TPN) differentially modulates ghrelin, inflammatory mediator production, and cardiac dysfunction induced by LPS. Rats received isocaloric parenteral or enteral nutrition through implanted vascular catheters or gastrostomy tubes for 7 days. Enteral nutrition was provided in conventional (TEN-C) and immunonutrition (TEN-I) formulations. Subsequently, rats were injected i.v. with LPS. Serum ghrelin, TNF-alpha, and high mobility group box 1 levels were determined by enzyme-linked immunosorbent assay. Myocardiac function was also assessed via the Langendorff isolated heart technique. The TEN-C increased plasma ghrelin and inhibited inflammatory mediators both before and after LPS administration when compared with TPN or TEN-I. Furthermore, animals receiving TPN and TEN-I had significantly lower left ventricular developed pressure but increased pressure development during isovolumetric contraction (dP/dt(max)) and relaxation (dP/dt(min)) when compared with animals receiving TEN-C after LPS-induced shock (P < 0.05). We conclude that TEN-C more effectively increased plasma ghrelin levels than TPN and TEN-I. The maintenance of higher ghrelin levels in TEN-C rats was associated with inhibiting various inflammatory mediators and maintaining cardiac function during LPS-induced septic shock.  相似文献   
68.

Introduction

Systemic inflammatory mediators, including high mobility group box 1 (HMGB1), play an important role in the development of sepsis. Anticoagulants, such as danaparoid sodium (DA), may be able to inhibit sepsis-induced inflammation, but the mechanism of action is not well understood. We hypothesised that DA would act as an inhibitor of systemic inflammation and prevent endotoxin-induced acute lung injury in a rat model.

Methods

We used male Wistar rats. Animals in the intervention arm received a bolus of 50 U/kg of DA or saline injected into the tail vein after lipopolysaccharide (LPS) administration. We measured cytokine (tumour necrosis factor (TNF)α, interleukin (IL)-6 and IL-10) and HMGB1 levels in serum and lung tissue at regular intervals for 12 h following LPS injection. The mouse macrophage cell line RAW 264.7 was assessed following stimulation with LPS alone or concurrently with DA with identification of HMGB1 and other cytokines in the supernatant.

Results

Survival was significantly higher and lung histopathology significantly improved among the DA (50 U/kg) animals compared to the control rats. The serum and lung HMGB1 levels were lower over time among DA-treated animals. In the in vitro study, administration of DA was associated with decreased production of HMGB1. In the cell signalling studies, DA administration inhibited the phosphorylation of IκB.

Conclusion

DA decreases cytokine and HMGB1 levels during LPS-induced inflammation. As a result, DA ameliorated lung pathology and reduces mortality in endotoxin-induced systemic inflammation in a rat model. This effect may be mediated through the inhibition of cytokines and HMGB1.  相似文献   
69.
Objective High mobility group box 1 (HMGB1) is an important factor in the development of sepsis. Previous work suggests that antithrombin III (ATIII) inhibits inflammation, but the mechanism of action is still poorly understood. Design and setting Prospective controlled animal study in a university laboratory. Materials Rats were randomly divided into a lipopolysaccharide (LPS)-induced sepsis control group and an ATIII-treated experimental group. Animals in the experimental group received a bolus of 250 units/kg of ATIII injected into the tail vein. Measurements and results Animals receiving high-dose ATIII (250 units/kg) had significantly improved lung histopathology and survival compared to the control rats. We measured serum and lung levels of various cytokines and HMGB1 at regular intervals from 0 to 12 h after the induction of sepsis and demonstrated lower HMGB1 levels over time in ATIII-treated animals. In an in vitro experiment, we stimulated the mouse macrophage cell line RAW 264.7 with LPS in the presence or absence of ATIII. Subsequent measurement of HMGB1 concentrations in the supernatant and cell signaling molecules in cell lysates revealed an ATIII dose-dependent decrease in HMGB1 release. Furthermore, inhibition of IkB and p42 phosphorylation was observed with the administration of ATIII, suggestive of downstream signaling pathways. Conclusions High-dose ATIII decreases lung pathology and reduces mortality in a rat sepsis model. This finding may be mediated by the inhibition of HMGB1. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. This article is discussed in the editorial available at: .  相似文献   
70.
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