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81.
中国发酵乳制品益生菌菌种的安全性评估   总被引:2,自引:0,他引:2  
本文对中国2000年~2006年发酵乳制品行业常用的137株益生菌菌种进行了毒力试验安全性评价,同时检测了31株益生菌对20种抗生素的耐药性,初步评估中国目前所使用的益生菌菌种安全性。结果表明:除一株鼠李糖乳杆菌外,其余益生菌菌种均为安全的。31株益生菌均对下列抗生素敏感:氨苄西林、青霉素、亚胺培南、庆大霉素、阿莫西林、阿莫西林/棒酸、加替沙星、红霉、素克林霉素、四环素、利福平和头孢噻肟;而对萘啶酮酸、万古霉素和磷霉素的耐药率较高。  相似文献   
82.
The increased prevalence of atopic diseases, i.e. atopic eczema, allergic rhinitis and asthma, has been described as the epidemic of the 21st century in Western societies. New approaches in the fight against allergic diseases are clearly called for, the target being the persistence of the allergic responder pattern beyond infancy. The advantage afforded by elimination diets lies in the silencing of specific allergic inflammation induced by an offending food. Novel nutritional approaches, beyond the treatment of food allergies, have recently attracted research interest subsequent to the identification of the immunomodulatory potential of specific dietary compounds. Dietary lipids as immunomodulators may prevent allergic sensitization by down-regulating inflammatory response whilst protecting the epithelial barrier. Probiotic bacteria have been shown to reinforce the different lines of gut defence: immune exclusion, immune elimination and immune regulation. On this basis, the strategy against allergic disease proposed here is based on the administration of tolerogenic gut-processed peptide fragments of a specific protein, in addition to the use of specific dietary compounds such as fatty acids and antioxidants, and introducing a microbial stimulus for the immature immune system by means of cultures of beneficial live micro-organisms characteristic of the healthy infant gut microbiota.  相似文献   
83.
抗幽门螺杆菌生物活性物质的研究进展   总被引:1,自引:0,他引:1  
喻钢  魏华  曾明 《药品评价》2006,3(2):130-136
本文对来源于益生菌、免疫球蛋白、乳铁蛋白和植物提取物中的抗幽门螺杆菌的生物活性物质的研究进展进行了综述,为研究开发新型制剂防治幽门螺杆菌感染提供了思路。  相似文献   
84.
The effects of probiotics, nonantigenic fractions of normal and malignant cells on tumors, and of similar fractions of normal cells on bacteria and viruses are discussed. The effects are considered in relation to tumor growth and development. In a control group of mice given subcutaneous inoculations only of viable dbrB tumor cells in DBA/1 mice, 100% developed tumors. In a group receiving subcutaneous and intravenous injections of tumor cells and given the tumor fractions, 20% developed lung tumors and 53% developed subcutaneous tumors. In an experiment in which mice received only intravenous injections of viable tumor cells and the tumor fractions, 100% of the controls died with no deaths occurring in the treated group. It is concluded that nonantigenic cellular fractions (probiotics) effective in inducing resistance to some bacterial and viral diseases are effective in inducing resistance to tumors in an inbred strain of mice.  相似文献   
85.
OBJECTIVES: The use of complementary and alternative medicines (CAM) appears increasingly prevalent in children and adolescents. Individuals with chronic illness may have patterns of greater usage. This questionnaire-based study aimed to ascertain the frequency of use by a group of children with proven inflammatory bowel disease (IBD) and to consider the reasons for their use. METHODS: A questionnaire was sent by mail to the parents of patients currently attending a paediatric IBD clinic. Parents were asked to describe their child's usage of alternative and probiotic therapies and to comment on a number of aspects of such therapies. RESULTS: Forty-six (77%) of 60 mailed questionnaires were returned. The mean age of the children was 10.9 (+/- 4.1) years and they were taking an average of 1.7 (+/- 0.8) prescribed medications. Thirty-three (72%) of the children were said by their parents to be having CAM, with four having five or more such therapies (average 2.4 +/- 1.3 agents per child). The most commonly used agents were probiotics (78%) and fish oils (56%). A minority (12%) of respondents reported that their child's CAM was very effective, although many (50%) noted partial benefits. The 13 children who had never used any CAM therapies ('non-users') did not differ from the 'users' in terms of gender, age, disease or duration of disease. As expected, non-users expressed greater concerns about use of CAM and described different attitudes towards such therapies. CONCLUSION: Complementary and alternative medicines, especially probiotic therapies, frequently are administered to children and adolescents with inflammatory bowel disease. Often this appears to be due to parental frustration with managing their child's chronic illness. Practitioners caring for children and adolescents with IBD need to be aware that their patients may be using alternative therapies and adopt an open attitude in this situation.  相似文献   
86.
D-lactic acidosis sometimes occurs in malabsorbed patients with short-bowel syndrome and is characterized by recurrent episodes of encephalopathy and metabolic acidosis. The characteristic neurologic abnormalities and the presence of metabolic acidosis raises a diagnostic suspicion, and the diagnosis is made when the serum level of D-lactic acid is greater than 3 mmol/L. Standard treatment consists of restricting oral carbohydrates or fasting, correction of metabolic acidosis, and a long-term suppression of pathogenic floras with antibiotics. The authors present a case of D-lactic acidosis in a 22-year-old patient with short-bowel syndrome, to whom intestinal bacterial agents (probiotics) were given in addition to oral kanamycin. Recolonization of the intestine with nonpathogenic floras should be a long-term treatment for D-lactic acidosis.  相似文献   
87.
BACKGROUND: Bacterial translocation is one important cause of nosocomial infections following major abdominal surgery. Oral administration of probiotics has been proposed to diminish bacterial translocation. MATERIAL AND METHODS: In total 68 rats were divided into seven groups: five of the groups received standard rat chow and were subjected to either sham-operation, 70% liver resection, colonic anastomosis, or a combination of 30 or 70% liver resection with synchronous colonic anastomosis, respectively. In two additional groups with synchronous operation, a combination of four different lactic acid bacteria and four fibers was administered two times daily pre- and postoperatively. Bacterial concentrations in cecum, mesenteric lymph nodes, liver, and spleen were analyzed and blood cultures were taken 48 h after operation. Furthermore, the following parameters were assessed: histological changes in the intestine, intestinal paracellular permeability (Ussing chamber), bursting pressure of the colonic anastomosis, and mitosis rate of the remnant liver. RESULTS: Bacterial translocation was observed in all rats, except in the sham group. Following liver resection, the highest bacterial concentrations were seen in liver and spleen, following colon anastomosis in the mesenteric lymph nodes. Bacterial translocation was increased in the animals with combined operation, in parallel to the extent of liver resection. In rats with colon anastomosis, bacterial concentration in the cecum was also higher than in the sham group. Application of probiotics significantly decreased bacterial concentration in the lymph nodes. In addition, animals with a high cecal concentration of lactobacilli had less translocation than the others. No histological changes were observed in the intestine. Paracellular permeability for ions, but not for the larger molecule lactulose, was increased in the colon in all groups with colon anastomosis. The bursting pressure of the colon anastomosis was not significantly different between the groups. Seventy percent liver resection led to a high rate of hepatocyte mitosis, whereas combination with colon anastomosis impaired the regeneration process. CONCLUSION: Synchronous liver resection and colon anastomosis led to increased bacterial translocation compared to the single operations in the rat model. It is possible to diminish this process by oral administration of probiotics. Bacterial overgrowth in the cecum and impaired hepatic regeneration, but not histological changes or alterations of paracellular permeability, are potential pathogenic mechanisms for translocation in this setting.  相似文献   
88.
PURPOSE: The purpose of this study was to demonstrate the potential of a dynamic, multicompartmental in vitro system simulating the human stomach and small intestine (TIM-1) for studying the behavior of oral drug dosage forms under various physiological gastrointestinal conditions. METHODS: Two model drug compounds were studied in TIM-1: a lyophilized Lactobacillus strain and paracetamol (acetaminophen). The Lactobacillus survival rate was determined by bacterial counting in the gastric and ileal effluents while simulating the conditions of the gastrointestinal tract of infants or adults. The availability for absorption of paracetamol from two oral dosage forms was investigated by measuring the drug concentration in jejunal dialysis fluid. The effect of gastrointestinal passage time and food intake on paracetamol absorption was also studied. RESULTS: The Lactobacillus survival rate in both gastric and ileal effluents was higher during simulation of the infant compared to adult conditions. We also showed that (i) paracetamol absorption was faster when it was administered as a free powder than in sustained-release tablet form, (ii) a slow passage time resulted in a delay in the absorption of paracetamol, and (iii) there was a lower rate of absorption when paracetamol was ingested with a standard breakfast as opposed to water. The in vitro results were consistent with in vivo data, showing the predictive value of TIM-1. CONCLUSIONS: TIM-1 is a powerful tool for supplying valuable information about the effects of various gastrointestinal conditions on biopharmaceutical behavior and efficacy of drug delivery systems in the development of oral formulations.  相似文献   
89.
A relationship between enteric microbiocenosis and severity of type 1 diabetes mellitus was detected. Microbiological analysis showed II-IV degree dysbacteriosis in all diabetic children. Long-term therapy with probiotics aimed at eradication of opportunistic microflora resulted in recovery of microbiocenosis, which was paralleled by improvement of the clinical status, regression of complications in children who were ill for a long time, and prevention of complications in children with newly detected diabetes. These results indicate the leading role of chronic enteric toxic infectious process in the development of complications of type 1 diabetes. The significance of infection in the pathogenesis of other noninfectious diseases in man is discussed.  相似文献   
90.
Summary Background Our studies were aimed at investigating the effect of lactic acid producing bacteria (LAB) or inulin, a natural source of non-digestible oligosaccharides derived from chicory, on the induction by carcinogens of aberrant crypt foci (ACF) in the colon, which are considered to be early precursor lesions of neoplasia. Methods Strains of Bifidobacterium longum, Lactobacillus casei and Lactobacillus acidophilus were administered to rats fed a purified high starch diet, under a variety of treatment protocols including daily gavage, via the drinking water and in the diet. The rats were treated with methyl-N-nitrosourea, 1,2-dimethylhydrazine, or azoxymethane (AOM) to induce ACF. Results In general, no consistent significant changes in ACF numbers were detected in these experiments. In one study, the basal diet of the rats was changed to one containing a higher level of fat (corn oil). Under these conditions, a significant decrease in AOM-induced colonic ACF was seen in rats given L. acidophilus or inulin. In a concurrent group of animals fed a low fat diet, no significant decrease in ACF was observed. Conclusions The results indicate that the type of diet fed can influence the detection of protective effects of LAB and oligosaccharides and that against the background of a diet with a level of fat typical of a Western diet, evidence for a protective effect of L. acidophilus and inulin towards colon cancer was obtained Received: 26 July 2001, Accepted: 26 November 2001  相似文献   
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