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31.
This report describes the dental management and 7-year follow-up of a 14-year-old boy who showed the typical characteristics of Lenz microphthalmia syndrome, a rare genetic disorder characterized by multiple abnormalities. The main features of the syndrome are microphthalmia, developmental retardation, ear abnormalities, microcephaly, skeletal, digital and urogenital anomalies. The dental anomalies include micrognathia, hypodontia, agenesis of permanent teeth, conic-shaped incisors, and taurodontic molars. The purpose of the report was to document specific oral manifestations and dental anomalies and their management associated with a previously reported case.  相似文献   
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BACKGROUND: The aim was to investigate the levels of malondialdehyde and total NO(2)(-) plus NO(3)(-) marker for NO(*) generation in gastric carcinoma and to correlate their levels with the cancer stage. METHOD: The pretreatment plasma samples were obtained from 38 patients with gastric cancer (seven patients at stage II, 19 at stage III and 12 at stage IV). Nitrite (NO(2)(-)) and nitrate (NO(3)(-)) levels, the end products of nitric oxide (NO(*)), were determined in these samples. NO(2)(-) was measured by using the Griess reaction and after enzymatic conversion of NO(3)(-) into NO(2)(-) by nitrate reductase, the resultant NO(2)(-) was also measured by the same method. Malondialdehyde (MDA), a lipid peroxidation marker, was measured by the thiobarbituric acid method. RESULTS: The levels of plasma MDA, NO(*) and NO(3)(-) were significantly higher in patients with gastric cancer compared with the healthy control group. Higher levels of MDA, NO(*) and NO(3)(-) were observed as the stage of the disease increased. CONCLUSION: We found that increased NO(*) production and MDA levels were present in plasma of patients with gastric cancer. These increases can be associated with the oxidant-antioxidant status in these patients.  相似文献   
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BACKGROUND: This study was designed to show the role of oxidative stress, nitric oxide and glutathione-related antioxidant enzymes in hypoxia/reoxygenation (H/R)-induced intestinal injury model in mice and to evaluate the potential benefits of arginine and carnitine supplementation. METHODS: A total of 28 young Balb/c mice were divided into four groups: Group 1 (untreated) was given physiological saline before the experiment; group 2 H/R mice were supplemented with L-arginine; group 3 H/R mice were given L-carnitine for 7 days; and group 4 mice served as controls. At the end of day 7, H/R injury was induced and intestinal tissue malondialdehyde (MDA), nitrate levels and glutathione peroxidase (GSH-Px), glutathione reductase (GR) and glutathione-S-transferase (GST) activities were measured. RESULTS: MDA levels were higher in the untreated animals than in the other three groups. MDA levels were higher in the L-arginine-treated animals than in the L-carnitine-treated animals. Nitrate levels were found to be increased in the L-arginine-treated group when compared to the controls. GSH-Px and GR activities were increased in the untreated, the L-arginine and the L-carnitine-treated H/R groups when compared to the control group. GST activities were indifferent between the groups. CONCLUSIONS: Oxidative stress contributes to the pathogenesis of H/R-induced intestinal injury. The glutathione redox cycle may have a crucial role in the H/R-induced intestinal injury. L-arginine and L-carnitine supplementations ameliorate the histological evidence of H/R-induced intestinal injury and decrease lipid peroxidation but do not alter the glutathione-related antioxidant enzyme activities.  相似文献   
35.
OBJECTIVE: To determine the location and radiological characteristics in children with abdominal hydatid disease (HD). MATERIALS AND METHODS: Thirty-one children (average age: 7.2 years) with abdominal HD were studied. The number, location, diameter and internal architecture of the cysts were assessed with abdominal ultrasonography (US) and computed tomography (CT). Density measurements and enhancement patterns were determined on CT. RESULTS: Twenty-one children had hepatic HD. The remaining 10 children had both hepatic and extrahepatic cysts. There were splenic cysts in five children, peritoneal cysts in two children and combined splenic and peritoneal cysts in three children. The most common site of the cysts was the liver (64%), followed by the spleen (20%) and the peritoneal cavity (16%). The seven intraabdominal cysts, which were not detected by US, were 20 mm or less in diameter. CONCLUSION: CT may demonstrate additional small intrahepatic or unsuspected extrahepatic cysts. Although rare, splenic or peritoneal hydatidosis should be included in the differential diagnosis of a cystic splenic or peritoneal lesion. Familiarity with atypical locations of HD may be helpful in making a prompt, accurate diagnosis. We think that in particular patients, especially those who had diagnostic problem and who are under surgical planning, CT should be performed additionally.  相似文献   
36.
Brain injury is the most frequent cause of mortality among patients with the hemolytic-uremic syndrome. Human brain endothelial cells (HBECs) are resistant to Escherichia coli-derived Shiga toxin (Stx); however, inflammatory cytokines markedly increase HBEC sensitivity to Stx cytotoxicity. HBECs were exposed to tumor necrosis factor (TNF)-alpha, with and without Stx-1, and cell survival, (125)I-Stx1 binding, globotriaosylceramide content, cell necrosis, and cell apoptosis levels were determined. TNF greatly increased Stx-1 cytotoxicity, primarily through induction of apoptosis, in HBEC.  相似文献   
37.
 The purpose of this study was to investigate the associations of tooth loss with skeletal bone mass, years since menopause, educational level, current smoking status, dietary calcium intake, and number of pregnancies in postmenopausal osteoporotic women in Turkey. The study population consisted of 1171 postmenopausal women aged 40–86 years (mean age, 61.19 ± 7.28 years). A detailed history was obtained from all women, including relevant lifestyle parameters, risk factors, and measurements of weight and height. Women were separated into three groups according to the number of teeth remaining as group 1 (edentulous, 457 women), group 2 (10 or fewer teeth, 232 women), and group 3 (more than 10 teeth remaining, 482 women). There was no significant difference among the three groups in mean age and menopausal age (P < 0.05). Body mass index of group 1 was significantly higher than that of group 2 (P < 0.01). Educational level was significantly different between three groups: groups 1 and 2 (P < 0.001), groups 1 and 3 (P < 0.0001), and groups 2 and 3 (P < 0.001). Educational level was lowest in group 1 and highest in group 3. Despite a low ratio of cigarette smoking in general, a smoking habit was most prevalent in group 3 and least in group 2. The ratio of women receiving adequate calcium was significantly lower in group 1 than in other groups (P < 0.001); mean calcium intake was similar in all groups. The number of pregnancies was significantly higher in group 1 than in other groups (P < 0.001). Lumbar bone mineral density (BMD) of group 1 was significantly lower than that of groups 2 and 3 (P < 0.001). Although no significant difference was found between groups 1 and 3, femoral neck BMD of group 2 was less than in others, and differences between groups 1 and 2 and between groups 2 and 3 (P < 0.001) were significant. Lumbar bone mineral content (BMC) of group 1 was significantly lower than that of groups 2 and 3 (P < 0.001), and lumbar BMC in group 2 was significantly higher than in group 3 (P < 0.05). Femoral neck BMC in group 1 was significantly higher than in groups 2 and 3 (P < 0.001). In conclusion, lumbar BMD and BMC in the edentulous group were significantly lower, whereas femoral neck BMD and BMC were significantly higher in edentulous group compared with the others. Our findings indicated that improvement in lifestyle factors and nutritional strategies for the treatment and prevention of osteoporosis may have additional benefit in reducing tooth loss. Received: February 18, 2002 / Accepted: June 21, 2002 Offprint requests to: A. Gur  相似文献   
38.
Effects of local anesthetics on pregnant uterine muscles   总被引:2,自引:0,他引:2  
Obstetric analgesia and anesthesia should provide optimal pain relief for the parturient with minimal risks. The local anesthetic agents are most commonly used for obstetric analgesia and anesthesia. We investigated the effect of local anesthetic agents: prilocaine, bupivacaine, ultracaine on myometrium in pregnant rats. In our study, we evaluated the effects of three local anesthetics at cumulative concentrations on contractions of myometrium isolated from pregnant rats. The following characteristics of the contractions were analyzed after the addition of drugs: frequency, mean duration, amplitude of each contractions and integrated area under the contraction curve. We observed that the exposure to prilocaine, bupivacaine and ultracaine decreased amplitude, duration and integrated area under the contraction curve. In conclusion, the study drugs at higher concentrations decreased contractions of myometrium, but all drugs at higher concentrations elevated the frequency.  相似文献   
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40.
Aim. Rasmussen encephalitis is associated with severe seizures that are unresponsive to antiepileptic drugs, as well as immunosuppressants. Transcranial direct current stimulation (t‐DCS) is a non‐invasive and safe method tried mostly for focal epilepsies with different aetiologies. To date, there is only one published study with two case reports describing the effect of t‐DCS in Rasmussen encephalitis. Our aim was to investigate the effect of t‐DCS on seizures in Rasmussen encephalitis and to clarify its safety. Methods. Five patients (mean age: 19; three females), diagnosed with Rasmussen encephalitis were included in this study. Patients received first cathodal, then anodal (2 mA for 30 minutes on three consecutive days for non‐sham stimulations), and finally sham stimulation with two‐month intervals, respectively. Three patients received classic (DC) cathodal t‐DCS whereas two patients received cathodal stimulation with amplitude modulation at 12 Hz. Afterwards, all patients received anodal stimulation with amplitude modulation at 12 Hz. In the last part of the trial, sham stimulation (a 60‐second stimulation with gradually decreasing amplitude to zero in the last 15 seconds) was applied to three patients. Maximum current density was 571 mA/m2 using 70 mm × 50 mm wet sponge electrodes with 2‐mA maximum, current controlled stimulator, and maximum charge density was 1028 C/m2 for a 30‐minute stimulation period. Results. After cathodal stimulation, all but one patient had a greater than 50% decrease in seizure frequency. Two patients who received modulated cathodal t‐DCS had better results. The longest positive effect lasted for one month. A second trial with modulated anodal stimulation and a third with sham stimulation were not effective. No adverse effect was reported with all types of stimulations. Conclusion. Both classic and modulated cathodal t‐DCS may be suitable alternative methods for improving seizure outcome in Rasmussen encephalitis patients.  相似文献   
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