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61.
Oligosaccharides are included among the anti-inflammatory components of milk because of their prebiotic properties and their capacity to act as receptors of microorganisms. Here the intestinal anti-inflammatory effect of goat milk oligosaccharides (O) was assessed in trinitrobenzenesulfonic (T) acid-induced colitis in rats. Rats were randomly assigned to three different groups. Two groups (T and OS) of colitic rats and a control group (C) were studied. Group OS received 500 mg/(kg.d) of goat milk oligosaccharides orally, starting 2 d before the colitis induction until d 6, and groups T and C received the vehicle. When compared with the T group, the OS group showed decreased anorexia and body weight loss; reduced bowel wall thickening and longitudinal extension of necrotic lesions; downregulated colonic expression of interleukin 1beta, inducible nitric oxide synthase, cyclooxygenase 2, and mucin 3; and increased trefoil factor 3. Thus, goat milk oligosaccharides have anti-inflammatory effects in rats with experimental colitis and may be useful in the management of inflammatory bowel disease.  相似文献   
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63.
Pregnant hamsters were treated with selenite, selenate, and selenomethionine during the critical stages of embryogenesis. The dosing regimens were oral, intravenous, and osmotic minipump infusion. Malformations, mainly encephaloceles, were noted with oral and intravenous selenite and selenate but were associated with maternal toxicity manifested by inanition and weight loss. Fetal body weights and lengths were reduced in a dose-dependent manner with the inorganic forms. Single oral doses of selenomethionine above 77 mumol/kg induced similar malformations but not when the dose was delivered orally over four days nor by minipump over several days. Fetal body weights and lengths were decreased by selenomethionine in a dose-dependent manner. Maternal toxicity was pronounced with the higher doses of selenomethionine. Assigning a specific teratogenic effect to selenium is confounded by maternal toxicity.  相似文献   
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65.
Experimental studies have demonstrated that dietary macronutrient distribution plays an important role in insulin regulation, a risk factor associated to obesity, diabetes and other metabolic disorders. To assess whether the macronutrient composition of the diet could be related to obesity onset by affecting the epigenetic regulation of gene expression, we investigated in rats the metabolic effects of two pair-fed isocaloric diets: control (rich in carbohydrates) and high fat diet (rich in fat; HFD). Compared to controls, HFD induced higher weight gain and adiposity and impaired glucose tolerance, which was accompanied by a slight increase in adiponectin levels and liver steatosis. Epididymal adipose tissue expression of the fatty acid synthase (FASN) gene and NADH dehydrogenase (ubiquinone) 1β-subcomplex 6 (NDUFB6) were significantly reduced in HFD group. These variations in mRNA levels were accompanied by changes in the methylation patterns of several CpG islands located in the promoter region of these genes. However, no correlations were found between gene expression and the methylation status. These results suggest that high fat intake produces overweighted rats independently of total energy intake. These diets could also induce some epigenetic changes in the promoters of key genes that could influence gene expression and may be behind metabolic alterations.  相似文献   
66.
Uncoupling Protein 1 (UCP1) is an inner mitochondrial membrane protein, uniquely expressed in brown adipocytes, which uncouples the mitochondrial respiration impairing ATP production and energy efficiency. The aim of the present study was to express UCP1 in liver mitochondria using a non-viral system in order to affect energy utilization. The effect of ectopic protein expression on liver energy metabolism, which was evaluated 42 h after DNA transfer, showed that mitochondria expressing UCP1 presented decreased ATP production, lasted more time in membrane potential state 3, and consumed more molecular oxygen to produce the same amount of ATP than the control group. In summary, the successful functionality of the mitochondrial protein, UCP1, after hydrodynamic delivery is a novel and significant finding. This approach could be useful to ectopically express mitochondrial proteins and, in this particular case, to manage metabolic disorders related to energy efficiency and expenditure, such as obesity.  相似文献   
67.
Alveolar and embryonal rhabdomyosarcomas are childhood tumors that do not respond well to current chemotherapies. Here, we report that the glycolytic inhibitor 2-deoxyglucose (2-DG) can efficiently promote cell death in alveolar, but not embryonal, rhabdomyosarcoma cell lines. Notably, 2-DG also induced cell differentiation accompanied by downregulation of PAX3/FOXO1a, the chromosome translocation-encoded fusion protein that is a central oncogenic driver in this disease. Cell death triggered by 2-DG was associated with its ability to activate Bax and Bak. Overexpression of the antiapoptotic Bcl-2 homologues Bcl-x(L) and Mcl-1 prevented apoptosis, indicating that cell death proceeds through the mitochondrial pathway. Mechanistic investigations indicated that Mcl-1 downregulation and Noxa upregulation were critical for 2-DG-induced apoptosis. In addition, 2-DG promoted eIF2α phosphorylation and inactivation of the mTOR pathway. Mcl-1 loss and cell death were prevented by downregulation of the endoplasmic reticulum (ER) stress-induced protein ATF4 and by incubating cells in the presence of mannose, which reverted 2-DG-induced ER stress but not ATP depletion. Thus, energetic stresses created by 2-DG were not the primary cause of cell death. Together, our findings suggest that glycolysis inhibitors such as 2-DG may be highly effective in treating alveolar rhabdomyosarcoma and that Noxa could offer a prognostic marker to monitor the efficacy of such agents.  相似文献   
68.

Objective

The aim of this study was to assess the efficacy and safety of a single intravenous (i.v.) bolus of dexketoprofen trometamol compared with an i.v. infusion of dipyrone in patients with moderate to severe pain due to renal colic.

Methods

A total of 308 patients with renal colic and visual analog scale (VAS) score ≥40 mm participated in a multicenter, randomized, double blind, double-dummy, parallel, and active-controlled study and were randomized to dexketoprofen 25 mg (n?=?101), dexketoprofen 50 mg (n?=?104), and dipyrone 2 g (n?=?103).

Results

Mean [± standard deviation (SD)] total pain relief (TOTPAR) scores were similar in the dexketoprofen 50 mg (15.3?±?8.6) and dipyrone (15.5?±?8.6) and slighly higher than in dexketoprofen 25 mg (13.5?±?8.6), although significant differences were not achieved. In the same way, patients in the dexketoprofen 50 mg and dipyrone groups showed higher scores in the sum of pain intensity differences (SPID) and the sum of analogue pain intensity differences (SAPID) than patients in the dexketoprofen 25 mg group, reaching statistical significance in comparison with dexketoprofen 25 mg and dipyrone for SPID and SAPID (p?p?Conclusions Dexketoprofen 50 mg administered as a single i.v. bolus was effective for the relief of moderate to severe pain in patients with renal colic, with a good safety profile and efficacy similar to i.v. dipyrone 2 g. Dexketoprofen produced analgesia that was faster in onset.  相似文献   
69.

Background  

The expression of some genes controlling energy homeostasis could be regulated by epigenetic mechanisms that may play a role in body weight regulation. Thus, it is known that various nutritional factors affect DNA methylation. In order to assess whether the macronutrient composition of the diet could be related to the epigenetic regulation of gene expression and with obesity development, we investigated the effects on methylation and expression patterns of two pair-fed isocaloric diets in rats: control (rich in starch) and HFS (rich in fat and sucrose).  相似文献   
70.
Human infection with the xenotropic murine leukemia virus-related virus (XMRV) has been associated controversially with prostate cancer and chronic fatigue syndrome. Information is lacking about the mechanisms of transmission and potential risk groups for XMRV infection. Plasma and peripheral blood mononuclear cells (PBMCs) from individuals with retroviral infections, chronic viral hepatitis, autoimmune diseases, prostate cancer, chronic fatigue syndrome, and blood donors were tested for XMRV markers. Antibodies to XMRV proteins p15E and gp70 were examined using research assays. DNA extracted from PBMCs was tested for the presence of XMRV gag and env sequences. A total of 1103 specimens belonging to individuals with chronic fatigue syndrome and/or fibromyalgia (437), prostate cancer (69), HIV-1 (149), HTLV-1/2 (31), chronic hepatitis B (81), chronic hepatitis C (72), autoimmune diseases (18), and blood donors (246) were examined. Overall, three samples (0.3%) were p15E seroreactive (two HTLV-1 and one HCV patient). Another 15 (1.4%) were gp70 seroreactive (six chronic fatigue syndrome-fibromyalgia, four blood donors, two HIV-1, one prostate cancer, one HBV, and one HCV). Four specimens were initially positive for XMRV gag sequences, but none could be confirmed by repeated testing. In summary, no evidence of XMRV infection was found in populations with retroviral and viral hepatitis infections in Spain. Likewise, XMRV was not recognized in patients with autoimmune diseases, chronic fatigue syndrome-fibromyalgia, prostate cancer, or healthy blood donors.  相似文献   
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