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41.
Aouad MT  Sayyid SS  Zalaket MI  Baraka AS 《Anesthesia and analgesia》2003,96(5):1325-7, table of contents
IMPLICATIONS: Supplementing a sevoflurane induction of anesthesia in children with IV lidocaine 2 mg/kg can suppress cough after tracheal intubation and thus improve intubating conditions. In addition, lidocaine minimizes blood pressure fluctuations after tracheal intubation.  相似文献   
42.
PURPOSE: Arsenic trioxide (As(2)O(3)), an inorganic arsenic compound, has recently been approved for the treatment of relapsed or refractory acute promyelocytic leukemia. However, systemic toxicity associated with As(2)O(3) treatment remains a problem. Inorganic arsenic is detoxified in vivo by methylation reactions into organic arsenic compounds that are less toxic. METHODS AND RESULTS: We investigated the antiproliferative and cytotoxic activity of dimethylarsinic acid (DMAA), an organic arsenic derivative and major metabolic by-product of As(2)O(3), against a panel of eight leukemia and multiple myeloma cell lines. As(2)O(3) was tested in comparison. In clonogenic assay, the average concentration of DMAA that suppressed cell colony growth by 50% was 0.5-1 m M, while for As(2)O(3) it was on average 1-2 microM. At those concentrations DMAA and As(2)O(3) had significantly less effect on colony growth of normal progenitor cells. Cytotoxic doses of DMAA and As(2)O(3) in 3-day trypan blue dye exclusion assay experiments were similar to doses effective in clonogenic assay. Assessment of apoptosis by annexin V assay revealed a high rate of apoptosis in all cell lines treated with DMAA and As(2)O(3), but significantly less effect on normal progenitor cells. DMAA, unlike As(2)O(3), had no effect on the maturation of leukemic cells. CONCLUSIONS: DMAA exerts differential antiproliferative and cytotoxic activity against leukemia and multiple myeloma cells, with no significant effect on normal progenitor cells. However, concentrations of DMAA needed to achieve such efficacy are up to 1000 times those of As(2)O(3). Evaluation of novel organic arsenic that would combine the high efficacy of As(2)O(3) and the low toxicity of DMAA is warranted.  相似文献   
43.
BACKGROUND: The sensitive guaiac faecal occult blood test, Haemoccult SENSA (HOS; Beckman Coulter, Fullerton, CA, USA), is our standard screening test for significant colorectal neoplasia. We evaluated an automatically-developed, quantified human haemoglobin immunochemical faecal test, OC-MICRO (Eiken Chemical Co., Tokyo, Japan), to improve test specificity and so reduce the colonoscopy burden. AIM: To compare guaiac faecal occult blood test and immunochemical faecal test diagnostic efficacy and costs for identifying significant neoplasia. METHODS: Colonoscopies were performed on patients who prepared three daily guaiac faecal occult blood tests with or without immunochemical faecal tests. RESULTS: Total colonoscopy was performed on 151 subjects who prepared both guaiac and immunochemical faecal tests (group 1) and the positive predictive values (PPV) were also compared to those of 162 subjects undergoing colonoscopy for positive guaiac faecal occult blood tests (group 2). In group 1, comparative sensitivity, specificity, and PPVs for significant neoplasia with guaiac faecal occult blood test were 75%, 34%, and 12% (PPV, 18% for group 2) and with immunochemical faecal test were 75%, 94% and 60% (P < 0.01 for specificity). The number of colonoscopy examinations needed to detect a significant neoplasm because of positive faecal occult blood tests was six to eight with HOS and two with OC-MICRO at 21-31% the cost of evaluating a positive guaiac faecal occult blood test. CONCLUSION: An immunochemical faecal test maintains the high sensitivity of guaiac faecal occult blood test, but significantly reduces the colonoscopy burden and screening costs.  相似文献   
44.
Hepatitis viral infections are important causes of morbidity and mortality in haemodialysis patients. The aim of the present work is to study the prevalence and possible risk factors of hepatitis C virus (HCV), hepatitis B virus (HBV) and dual infection in haemodialysis patients. Three hundred forty patients with end-stage renal disease, 266 males (78.2%) with mean age of 50.9?±?11.6 years and 74 females (21.8%) with mean age of 53.5?±?10.5 years on haemodialysis, were recruited from four haemodialysis units. They were screened for the presence of HCV, HBV and dual HCV and HBV infections and possible risk factors for acquiring these infections in those patients during the period between June 2007 and August 2009. One hundred ninety-six (57.7%) patients were HCV positive while 12 (3.5%) patients had HBV infection. A dual infection with both viruses was observed in 26 patients (7.6%).There was a significant difference in the number of blood transfusions among HCV-positive, HBV-positive and dual infection patients and negative patients (12.4?±?7.6, 13.8?±?6.8, 13.5?±?8.3 vs. 5.2?±?3.4 transfusions, p?<?0.01). HCV, HBV and dual HCV and HBV patients have been on dialysis for a longer period than the negative patients (7.5?±?5, 6.2?±?3.6, 7.5?±?5.4 vs. 4.4?±?4 years, p?<?0.01). Higher HCV was associated with longer haemodialysis duration and history of previous blood transfusion and not associated with dialysis in multicentres. HBV and dual infection is less prevalent than HCV in haemodialysis units.  相似文献   
45.
Chemical investigation of the cytotoxic and anti-tuberculosis active butanone extract obtained from the growth media of the marine-derived fungus Beauveria felina led to the isolation of two new destruxins, [beta-Me-Pro] destruxin E chlorohydrin (1) and pseudodestruxin C (3), along with five known cyclic depsipeptides. The structures of the new destruxin derivatives were established by analysis of spectroscopic data, while the absolute configuration of the common amino acid residues was established by Marfey's analysis. The absolute configuration of the 2(R),4(S)-5-chloro-2,4-dihydroxypentanoic acid residue in 1 could be established by application of a J-based configuration method followed by derivatization with R-MPA-Cl and NMR analysis.  相似文献   
46.
The authors investigated the antinociceptive activity of sildenafil and adrenergic agents co-administered in the writhing test in mice. The intensity of nociception was quantified by the number of writhes occurring between 0 and 30 min after stimulus injection. Nontreated groups (NT) received acid intraperitoneally (ip) followed by sterile saline (ip). Animals received (ip) sildenafil (2.5 or 5 mg/kg), propranolol (0.5 or 2 mg/kg), atenolol (0.05 or 2 mg/kg), prazosin (0.05 or 0.25 mg/kg) or clonidine (0.01 or 0.1 mg/kg) 30 min before acid injection. It was observed that only the largest doses of every drug inhibited the number of writhes in mice. In another series of experiments, animals were pretreated with the lower ineffective doses of propranolol, atenolol, prazosin or clonidine. After 30 min, mice also received the lower ineffective dose of sildenafil followed by acid injection. The combination of ineffective doses of propranolol, atenolol, prazosin or clonidine with sildenafil significantly inhibited the nociceptive response induced by acetic acid injection. Data obtained from these experiments showed that ineffective doses of sildenafil associated with ineffective doses of adrenergic agents provided analgesic effects in the writhing test.  相似文献   
47.
OBJECTIVE: To examine the relationship between the presence of enamel defects, dental caries in primary teeth, and exposure to various fluoride technologies and the presence of dental caries in permanent teeth in children with mixed dentition. MATERIALS AND METHODS: A cross-sectional study was conducted in 713 children aged 6-9 years old in 4 elementary schools in Campeche, Mexico through the use of a questionnaire for the mothers and an oral examination in the children. The dependent variable was the prevalence of caries in permanent dentition. RESULTS: The mean number of decay, missing or filling teeth in primary dentition (dmft) and in permanent dentition (DMFT) was 2.48 (2.82) (deft > 0 = 58.9%) and 0.40 (0.98) (DMFT > 0 = 18.2%), respectively. The significant caries index (SiC), which is calculated in deciduous dentition, was 5.85 for 6 year-olds. Multivariate logistic regression adjusted for variables related to fluoride exposure revealed that older age (OR = 2.99), a deft of > 0 (OR = 5.46), and lower maternal educational level (OR = 1.57) were significantly associated with a higher number of dental caries in permanent teeth. An interaction between sex and enamel defects was also found. CONCLUSIONS: The number of dental caries in both primary and permanent dentitions was relatively smaller than that found in prior studies performed in Mexican populations. The results confirm that the presence of caries in primary dentition is strongly associated with caries in permanent dentition. No significant relationship was found between fluoride exposure and dental caries in permanent dentition.  相似文献   
48.
Eotaxin/CCL‐11 is a major chemoattractant that contributes to eosinophilic inflammation in asthma. Glucocorticoids inhibit inflammation, but long‐time exposure may cause paradoxical adverse effects by augmenting eotaxin/CCL‐11production. The aim of this study was to determine if 7,4′‐dihydroxyflavone (7,4′‐DHF), the eotaxin/CCL11 inhibitor isolated from Glycyrrhiza uralensis, reduces in vitro eotaxin production induced by long‐time dexamethasone (Dex) exposure, and if so, to elucidate the mechanisms of this inhibition. Human lung fibroblast‐1 cells were used to identify the potency of 7,4′‐DHF compared with other compounds from G. uralensis, to compare 7,4′‐DHF with Dex on eotaxin production following 24‐h short‐time culture and 72‐h longer‐time (LT) culture, and to determine the effects of the 7,4′‐DHF on Dex LT culture augmented eotaxin production and molecule mechanisms. 7,4′‐DHF was the most potent eotaxin/CCL‐11 inhibitor among the ten compounds and provided continued suppression. In contrast to short‐time culture, Dex LT culture increased constitutively, and IL‐4/TNF‐α stimulated eotaxin/CCL11 production by human lung fibroblast‐1 cells. This adverse effect was abrogated by 7,4′‐DHF co‐culture. 7,4′‐DHF significantly inhibited Dex LT culture augmentation of p‐STAT6 and impaired HDAC2 expression. This study demonstrated that 7,4′‐DHF has the ability to consistently suppress eotaxin production and prevent Dex‐paradoxical adverse effects on eotaxin production. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
49.
50.
Galactoceles in children, either cystic or pseudotumors, are described in the literature as a rare cause of increasing breast size and can appear in males. We report a case of galactocele in a 15-month-old male, treated at our institution. The patient presented with a tumor in the right breast that had appeared 6 months earlier with no pain, signs of inflammation, or nipple secretion. Twelve cases found in the literature emphasize the importance of including galactocele in the differential diagnosis of benign breast masses in infancy.  相似文献   
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