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51.
We report a 15‐year‐old girl who presented with indurated, subcutaneous nodules in addition to classical findings of juvenile dermatomyositis. Histopathological examination confirmed the diagnosis of panniculitis associated with juvenile dermatomyositis. Considering that panniculitis is a rare cutaneous manifestation of juvenile dermatomyositis, we present a patient with a brief review of the published work to highlight the importance of keeping juvenile dermatomyositis in mind among the etiologies of pediatric panniculitis.  相似文献   
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The purpose of this retrospective study was to evaluate the characteristics of cases of acute poisoning in adults who were admitted to emergency service over a 3-year period. Clinical charts were analyzed retrospectively for etiologic and demographic patient characteristics. A total of 810 adults were admitted to the emergency center with acute poisoning. The female-to-male ratio was 2:1. Mean ages of female and male patients were 28.8±12.9 years and 35.1 ±15.4 years, respectively, and many patients (46.9%) were between the ages of 16 and 25 years. Medicinal drugs were found to be the primary cause (60.5%) of poisoning, and tricyclic antide-pressants were the most frequent causative agents (36.3%). Seasonal distribution of poisoning cases suggested a peak in the summer months (35.4%). Overall, 68.6% of acute poisonings were suicide attempts, and of these patients, 84.9%, 14%, and 1.1% were attempting suicide for the first, second, and third times, respectively. Among 810 cases of acute poisoning, 15 were fatal. The following conclusions were reached by investigators: (1) in the test region, younger females, especially single females, were at greater risk for poisoning than other patient groups, (2) self-poisoning cases constituted the majority of all poisonings, and (3) the main agents of self-poisoning were medicinal drugs, with antidepressants used most frequently. It was also found that unintentional poisoning commonly resulted from intake of foods, especially mushrooms.  相似文献   
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It is well established that some agents such as aminoglycosides generate free oxygen radicals, leading to an increased oxireductase production, which in turn increases tissue toxicity. The aim of this study is to test whether melatonin, the chief secretory product of the pineal gland and a highly effective antioxidant and free radical scavenger, reduces the nephrotoxicity caused by amikacin (AK). Herein, we investigated the physiologic and pharmacological role of melatonin in influencing AK-induced nephrotoxicity. For this, pinealectomized (Px) and sham operated (non-Px) rats were used. Both AK and melatonin were administered to all groups. We investigated the effects of melatonin on AK-induced changes in levels of malondialdehyde (MDA), a lipid peroxidation product, glutathione (GSH), an antioxidant whose levels are influenced by oxidative stress, and blood urea nitrogen (BUN) and serum creatine (Cr) levels. Morphologic changes in the kidney were also examined by using light microscopy. MDA levels were found to be higher in Px than in non-Px AK-treated animals. Melatonin administration to Px rats reduced MDA levels. In relative to non-Px rats, Px animals treated with AK had significantly lower GSH concentrations while melatonin administration elevated GSH levels in the kidney; however, this stimulatory effect of melatonin was not observed in non-Px AK-treated rats. Treatment with AK alone resulted in significantly higher plasma Cr and BUN levels. Repeated administration of melatonin prevented the AK-induced elevation of plasma Cr and BUN levels. Morphologic damage to renal tubules as a result of AK was more severe in the renal cortex than in the medulla. The damage to the kidney induced by AK was reversed by melatonin in the Px rats. In conclusion, these results show that physiologic melatonin concentrations are important in reducing AK-induced renal damage, while pharmacologic concentrations of melatonin did not add to the beneficial effect.  相似文献   
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The interdomal fat pad (IFP) is an important structure related to tip deformity in rhinoplasty. This study aimed to evaluate the IFP by ultrasonography before surgery, and to demonstrate the existence of the IFP as a distinct anatomic structure in cadavers and patients. Three dimensions of the IFP were measured in 23 patients using ultrasound before rhinoplasty and in 10 cadavers using dissection. All fat pads were examined by histopathologic methods. In the cadavers, three dimensions of the IFP were found: 2.3 × 3.7 × 12.8 mm. In the patients, three dimensions of IFP were measured by ultrasonography: 2.8 × 4.1 × 13.7 mm. Histopathologic examinations showed that the IFP is a structure differentiated from subcutaneous tissue. The IFP was demonstrated in all cadavers and patients by surgical and radiologic methods. All cases had a fat pad in the interdomal space with varying sizes.  相似文献   
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The aims of this study were to observe the changes in antioxidative defense enzymes and renal morphology after 7,12-dimethyl-benz[a]anthracene (7,12-DMBA) administration in mice and to investigate the possible protective effects of melatonin against 7,12-DMBA-induced renal damage in comparison with vitamin E + selenium (vit E + Se). Forty female mice were divided into four groups: control, DMBA, DMBA + vit E + Se and DMBA + melatonin. In the DMBA group, mice were given injections of 7,12-DMBA (20 mg/kg). DMBA + vit E + Se group mice received injections of 7,12-DMBA + vit E + Se (20 mg/kg + 90 mg/kg + 1.8 microg/kg). In the melatonin group, mice were given injections of 7,12-DMBA + melatonin (20 mg/kg + 4.2 mg/kg). The experiment lasted for 21 days. Mice were killed and the kidneys were taken for enzyme analyses and histologic examination. Catalase (CAT) and glutathione peroxidase (GSH-Px) activities were found significantly decreased in the DMBA group and in the DMBA + vit E + Se group when compared with the control group (P < 0.05), whereas CAT and GSH-Px activities were found significantly elevated in the DMBA + melatonin group when compared with the control (P < 0.05) and the DMBA group (P < 0.01). Exposure to DMBA resulted in tubular alterations in renal cortex. Morphometric analysis revealed proximal and distal tubular damage (P < 0.05). These alterations were found to be prevented by melatonin but not with vit E + Se administration. These results reveal that melatonin stimulates CAT and GSH-Px activities and prevents renal injury better than vit E + Se combination in mice kidneys.  相似文献   
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The rate of hepatocellular carcinoma (HCC) is increasing in Egypt where the major risk factors are chronic infections with hepatitis B and C viruses (HBV and HCV). A major segment of the population is employed in agriculture, raising the possibility that exposure to pesticides is an additional risk factor for HCC. The objective of this study is to investigate pesticides as environmental risk factors for HCC while taking into account viral risk factors. We conducted a case-control study of 236 subjects with confirmed HCC recruited from the National Cancer Institute, Cairo University, Egypt, and 236 controls matched on sex, age group and urban-rural status recruited from orthopedic department, Cairo University Hospital, Egypt. Patients who agreed to participate signed a consent form, answered a questionnaire and gave a blood sample for hepatitis virus testing. The manuals of the Ministry of Agriculture for approved use and type of pesticides since 1965 were linked to the questionnaire data for types of crops and pests that the subject had to combat, to attribute specific pesticides that were used by each subject. Subjects also reported duration of the exposure (years). Case-control comparisons in these data were stratified by sex, age group, and urban vs. rural residence. Data were analyzed using unconditional logistic regression models adjusting for age, HCV RNA, and current hepatitis B infection. Among rural males, the adjusted odds ratio (OR) for organophosphorus compounds was 2.7 (95% CI = 1.3-5.3) and for carbamates it was 2.9 (95% CI = 1.4-5.8). No statistically significant associations between HCC and pesticides were observed for urban males or for females. As expected, the strongest risk factors for HCC in this study were HCV RNA (OR = 16-17) and current HBV infection (OR = 27-28). This study therefore suggests that exposures to organophophorus and carbamate pesticides are additive risk factors to current HCV and HBV infection among rural males. Future investigation should address the possible hepatocarcinogenicity of pesticides using biomarkers of exposure and other techniques to better estimate dose-response relationships.  相似文献   
59.
Previous observations demonstrated that physiological levels of melatonin, the pineal secretory product, are important in protecting against oxidative stress-induced tissue damage. We investigated the effects of pinealectomy and administration of exogenous melatonin on liver tissue in rats. Pinealectomized (Px) and sham-operated (non-Px) rats were used. We evaluated structural changes, reduced glutathione (GSH) levels and malondialdehyde (MDA) levels. Rats were divided into three groups (10 rats in each group): control (non-Px), Px+vehicle and Px+melatonin (4 mg/kg given daily intraperitoneally for 10 days). Liver GSH levels were significantly lower in Px rats than in the control group. Melatonin administration significantly increased GSH levels (p < 0.05). Px caused a significant increase in MDA levels as compared with the control group and melatonin administration to Px rats significantly reduced MDA levels in the liver (p < 0.05). Sinusoidal dilatation to a varying degree developed in all Px rats. Severity of mononuclear cell infiltration and sinusoidal congestion were lower in Px+melatonin group than in the Px group. These findings suggest that a significant increase in oxidative and structural changes occur in rat livers after pinealectomy, which can be diminished by melatonin treatment.  相似文献   
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