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81.
82.
Introduction. It was previously demonstrated that decreased maternal blood flow might create impairment in skin development. The aim of this study was to show by means of lipid peroxidation the effect of intrauterine ischaemia–reperfusion injury on fetal rat skin. Methods. In total, 24 female Spraque‐Dawley rats, 19 days pregnant, were used. They were separated into three groups (n = 8): a control group, a sham‐operated group and an experimental group. Laparotomy was performed on all three groups. In the sham‐operated and experimental groups, utero‐ovarian artery dissection was performed in addition. In the experimental group, fetal ischaemia was induced by clamping the utero‐ovarian artery bilaterally for 30 min, and reperfusion was achieved by removing the clamps for 60 min. At the end of the experiment, the fetuses were removed by caesarean section and skin specimens were taken from the fetuses. Lipid peroxidation in the skin tissues was determined as thiobarbituric acid reactive substance (TBARS) concentration for each fetal rat. One‐way ANOVA and post hoc tests were used for statistical analysis. Results. The level of TBARS was significantly increased in the fetal rat skin after ischaemia–reperfusion injury compared with the control group. Conclusion. Lipid peroxidation has an important role in intrauterine ischaemia–reperfusion‐induced fetal skin damage in rats.  相似文献   
83.
The effects of noise on hearing and oxidative stress in textile workers   总被引:2,自引:0,他引:2  
The aim of this study was to investigate the effects of noise on hearing, lipid peroxidation and antioxidant enzymes in textile workers. Thirty textile workers exposed to high noise 105 dB (A) in a textile factory, and 30 healthy male volunteers in our hospital as a control group were included in the study. In both groups, following audiometric tests, blood samples were obtained. In these blood samples, Malonydialdehyte (MDA), Superoxide dismutase (SOD) and Catalase (CAT) levels were investigated. Statistical analysis was performed by using SPSS version 11.0 (SPSS Inc., Chicago 1L) software program. Mean pure tone audiometric thresholds in workers were significantly higher than in control subjects at frequencies 2,000, 4,000 and 6,000 Hz (p<0.05). Hearing losses were more evident at high frequencies (4-6 kHz) than at low frequencies in worker group. (p<0.05). It was observed that textile workers with longer employment duration had poorer hearing threshoulds and the hearing loss had started on those who had worked for 5-8 yr. While MDA levels were significantly higher in workers than controls (p<0.001), CAT activity was significantly lower (p<0.005). Also, SOD activity was lower in workers but difference was not statistically significant. We observed a significant change in hearing threshold of the textile workers compared with that of the control group. Increase in MDA level and decreases in CAT and SOD activities in textile workers, support the opinion that the noise causes the oxidative stress. The fact that noise both causes hearing loss and increases oxidative stress suggests that there may be a relationship between the oxidative stress and hearing loss. But, further studies are needed in order to verify this opinion.  相似文献   
84.
BACKGROUND: Alzheimer's disease (AD) is a neurodegenerative disorder in middle and late age. Ribosomal RNA (rRNA) genes are located in the nucleolus (nucleolar organizer regions = NORs). There are increased deposits of beta-amyloid protein in the brains of the patients with AD and aged individuals with Down's syndrome (DS). The beta-amyloid gene is located in the acrocentric chromosome 21 that is responsible for rRNA synthesis. Therefore, it is possible that there is a relationship between ribosomal genes and AD. Objective: To investigate the activities of ribosomal genes of AD patients by comparing the activities of NORs in AD patients and healthy controls with the silver-staining method. METHODS: NOR surface/the total nucleus surface proportions in interphase nuclei, and silver stainability and satellite association (SA) of acrocentric chromosomes in the metaphases of cultivated lymphocytes of 20 AD patients and 20 healthy controls (10 elderly and 10 young) were evaluated. RESULTS: A decrease in NOR surface/total nucleus surface proportions has been observed in the interphase nucleus of AD patients when compared with elderly controls (p = 0.035). When compared with the sizes of Ag+ segments of acrocentric chromosomes of AD patients and control groups, the Ag-staining size 1 of the chromosome 22 of AD patients was found to be more increased than that of the young controls (p = 0.018). There was no statistically significant difference between AD patients and control groups regarding the number of Ag+ acrocentric chromosomes, Ag+ chromosome 21 and SA frequency (p > 0.05). It has been found that there is only a slight increase in the total number of chromosomes in SA in AD patients when compared with elderly controls (p = 0.05). CONCLUSION: The decrease in NOR surface/total nucleus surface proportions of AD patients may indicate a reduction in the activity of the ribosomal genes of these patients.  相似文献   
85.
Melatonin, a product of the pineal gland, is an effective free-radical scavenger both in vitro and in vivo. Free-radical-mediated lipid peroxidation has been increasingly considered as an important factor in post-traumatic neuronal degeneration. The aim of the present study was (i). to examine the responses of different regions of central nervous system (CNS) to free-radical generation induced in vitro and (ii). to test the efficacy of melatonin in reducing oxidative damage in different regions of the CNS. Rat brain, total spinal cord, spinal cord white matter and optic nerves were dissected with the rats under general anesthesia and immediately frozen at -20 degrees C. Thiobarbituric acid reactive substances were measured as an index of lipid peroxidation. Peroxidation was induced with ferrous iron (0.02 mm), ascorbate (1 mm), and hydrogen peroxide (H2O2) (0.5 mm). All tissue samples showed increased lipid peroxidation levels after treatment with free-radical generating agents. The highest amount of damage was observed in the presence of ferrous iron, ascorbate, and H2O2. Melatonin showed antioxidant effects in the brain, total spinal cord, optic nerve, and spinal cord white matter. The results show that melatonin has differential protective effects on CNS tissues in vitro and the most potent effect is observed in the spinal cord white matter.  相似文献   
86.
Schnell O  Kilinc S  Rambeck A  Standl E 《Herz》2004,29(5):519-523
BACKGROUND AND AIM: There is scintigraphic evidence that insulin improves cardiac autonomic innervation in diabetic patients. The aim of the study was to assess the effects of insulin therapy on parameters of cardiac reflex tests in type 2 diabetic patients. PATIENTS AND METHODS: 30 type 2 diabetic patients with an HbA(1c) of > 7.5% under oral antidiabetic agents were included into the 4-month follow-up. Insulin therapy was performed according to standardized clinical guidelines. Parameters of five cardiac reflex tests were assessed to study cardiac autonomic function: Coefficient of variation (CV) of heart rate variation (HRV) at rest and during deep breathing, HRV in response to standing (max./min. 30:15-ratio), Valsalva ratio, systolic blood pressure response (> 1 test abnormal = cardiac autonomic neuropathy [CAN]). QT(QTc)-interval was also assessed in the patients. RESULTS: At 4-months follow-up, mean insulin dosage in the patients was 25 +/- 8 IU/day. HbA(1c) was decreased from 9,2 +/- 0,7 to 7.2 +/- 0.6 % (p < 0.001). Three parameters of cardiac autonomic function were significantly improved: CV of HRV at rest 2.79 +/- 0.84 versus 2.96 +/- 0.85 (p < 0,001), CV of HRV during deep breathing 4.15 +/- 1.46 versus 4.38 +/- 1.68 (p = 0.002), 30:15 ratio 1.06 +/- 0.05 versus 1.09 +/- 0.04 (p < 0.05). Length of QTc- Interval changed significantly from 417 +/- 12 ms at month 0 to 398 +/- 11 ms at month 4 (p<0.05). CONCLUSIONS: The study demonstrates that insulin therapy with regular insulin optimizes cardiac autonomic function in type 2 diabetes mellitus. It emphasizes the value of cardiac reflex tests with regrad to follow-up of cardiac autonomic function in diabetes.  相似文献   
87.
88.
Neurogenic inflammation in the dura mater caused by trigeminal nociceptive activation has been implicated in the pathophysiology of migraine. Vasoactive intestinal polypeptide (VIP) is a powerful neuroprotective neuropeptide that can modulate mast cell behavior. Migraine is also associated with sympathetic insufficiency. This study investigates the effects of VIP on the number of mast cells in the dura mater and on c‐Fos expression in the trigeminal nucleus of sympathectomized rats. Experiments were carried out with 32 Sprague‐Dawley male rats with body weights of 200–250 g. In the sympathectomized group, the left superior cervical sympathetic ganglion was removed. In the sympathectomized + VIP group, postoperative VIP 25 ng/kg/day (0.2 ml) was administered for 5 days. In the sham group, the ganglion and nerves were exposed but not dissected. Dura maters were stained with toluidine blue, and brainstems were labeled by indirect immunohistochemistry for c‐Fos. Sympathectomy significantly increased the number of mast cells in both the ipsilateral and the contralateral dura mater (P < 0.001). VIP decreased the number of mast cells in both sides of the dura mater in sympathectomized rats. VIP also decreased c‐Fos expression in the ipsilateral trigeminal nucleus of sympathectomized rats (P < 0.001). In the context of an experimental superior cervical ganglionectomy model of migraine, VIP is an efficient modulator of neurogenic inflammation of the dura. © 2014 Wiley Periodicals, Inc.  相似文献   
89.
Sydenham's chorea is still the most frequently seen form of acquired chorea in childhood in developing countries. Nine patients presented with Sydenham's chorea as one of the major criteria (one or more attacks) were evaluated their clinical characteristics and treatment. All patient were given sodium valproate. Clinical improvement began 11+/-4.0 days in sodium valproate treatment, and no adverse effect was seen due to the drugs. Echocardiography revealed rheumatic carditis sequela in all patient. The nine Sydenham's chorea patients presented 13 attacks of chorea in follow-up. We observed isolated chorea in 44% of patients, and 22% presented one or more recurrences. The interval between the attacks ranged from months to 2 years. The 90% of the patients were not on prophylaxis with benzathine penicillin. One patient had diagnosis of obsessive-compulsive disorder, and one had diagnosis of attention deficit hyperactivity disorder in the follow-up period. This report emphasizes the significance of Sydenham's chorea and sequela of rheumatic carditis association and a high risk of developing neuropsychiatric disorders in the follow-up period. Valproic acid is an effective and safe drug in the treatment of Sydenham's chorea.  相似文献   
90.
Case 1: A 58-year-old man presented with a solitary asymptomatic nodule on his thumb (Figure A). After trauma with a rusty nail approximately 20 years ago, he had developed a small papule, which had enlarged gradually for a few days initially before stabilizing. His personal and family medical histories were unremarkable. Dermatologic examination revealed a 1-cm crater-like nodule on the left palmar area. This was a firm and nontender lesion that was fixed to the overlying skin but moved freely from underlying structures. There were no similar lesions elsewhere on his body. Case 2: A 52-year-old man presented with a nodular lesion on the left palmar surface of his thumb. The 0.8-cm lesion was lightly colored, with a central cup-shaped epidermal depression and thin epidermis. The patient described an insect bite to the area 15 years earlier as the precipitating event. The firm and nontender lesion was fixed to the overlying skin but moved freely from underlying structures (Figure B). Case 3: A 36-year-old man consulted for a nodular lesion, located on his left palmar surface, that had not enlarged or changed since appearing 3 years ago. He described mechanical trauma to the area as precipitating the lesion. Clinical examination revealed a 0.6-cm, well-circumscribed nodule, with a dome shape and colored skin. Clinically, the nodular lesion appeared to be a benign tumor (Figure C). In each case, the nodule was excised totally and histopathologic examination revealed a well-circumscribed, nonencapsulated nodule within the mid-dermis. Thick, acellular collagen bundles were arranged randomly in short fascicles through the center of the lesion. Cellular areas consisting of histiocytes and fibroblasts with a storiform pattern at the periphery of lesion were observed, but nuclear atypia and mitotic activity were not. Results of immunohistochemical stain with CD34 were negative, but in all cases were strongly positive for Factor XIIIa. Slight epidermal hyperplasia was present with orthokeratotic hyperkeratosis and flattened rete ridges in the overlying epidermis (Figure A-1, Figure B-1, Figure C-1). The subcutaneous fat and adjacent skin were normal. No folliculosebaceous units at the periphery of the lesion were seen, but a few eccrine sweet glands were noted. No recurrence appeared in 18 months of follow-up.  相似文献   
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