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This study was designed to investigate the protective effects of vitamin C and vitamin A on oxidative renal tissue damage. Male Wistar rats were given an intraperitoneal injection of 0.5 ml saline (control) or 0.5 ml solution of lipopolysaccharide (10 mg/kg), which caused endotoxemia. Immediately (within 5 min) after the endotoxin injection, the endotoxemic rats were untreated or treated with intraperitoneal injection of vitamin A (195 mg/kg bw), vitamin C (500 mg/kg bw) or their combination. After 24 hours, tissue and blood samples were obtained for histopathological and biochemical investigation. Endotoxin injection caused renal tissue damage and increased erythrocyte and tissue malondialdehyde (MDA) and serum nitric oxide (NO), urea and creatinine concentrations, but decreased the superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) activities compared to the parameters of control animals. Treatment with vitamin C or with vitamins C and A significantly decreased the MDA levels and serum NO, urea and creatinine levels, recovered the antioxidant enzyme activities (SOD, GSH-Px and CAT), and prevented the renal tissue damage in endotoxemic rats. In contrast, vitamin A alone did not change the altered parameters except for creatinine levels. Notably, the better effects were observed when vitamins A and C given together. It is concluded that vitamin C treatment, alone or its combination with vitamin A, may be beneficial in preventing endotoxin-induced oxidative renal tissue damage and shows potential for clinical use.  相似文献   
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The role of autoimmunity in the development of Sheehan’s syndrome is obscure. There are a limited number of studies investigating the immunological alterations accompanying Sheehan’s Syndrome. Our objective was to evaluate lymphocyte subsets in these patients. We conducted a cross-sectional clinical study. Cytofluorometry was used for the immunophenotyping of peripheral blood leukocytes from patients with Sheehan’s syndrome followed up in the endocrine clinic during 2005–2009. Fifteen consecutive patients (mean age 61.6 ± 11.3, range 34–75 years) and 25 healthy controls (mean age 56.7 ± 10.6, range 34–80 years) were included. There was no statistically significant difference between the groups in terms of mean age. The percentages of CD19+, CD16+/56+, CD8+28?, γδTCR+, CD8+; the total lymphocyte counts; and the ratio of CD8+28?/CD8+28+ were similar (p > 0.05) between patients and controls. Whereas the leucocyte counts (p = 0.003), the percentage of CD3 + DR + (p < 0.001), CD8+28+ (p = 0.030), CD4+CD25+ (p = 0.007), the ratio of CD3 + DR+/CD3 (p < 0.001) were higher; the percentage of CD3 (p = 0.020), CD4 (p < 0.001) and the ratio of CD4/CD8 (p = 0.006) were lower in patients with Sheehan’s syndrome compared to healthy controls. There was a positive correlation between the duration of illness and the percentage of CD3+DR+ (r = 0.53, p = 0.03) expression. Some peripheral lymphocyte cell subsets show marked variation in patients with Sheehan’s syndrome in comparison to matched healthy subjects, which may have implications for altered immune regulation in these patients. High CD3 + DR + expression that correlates with the duration of illness in Sheehan’s patients is suggestive of an ongoing inflammation accompanying the slow progression of pituitary dysfunction in Sheehan’s syndrome. It is not clear if these cellular alterations contribute to the cause or consequence of pituitary deficiency in Sheehan’s syndrome.  相似文献   
105.

Introduction

Imbalance between secretion and absorbtion of pleural fluid results in pleural effusion. Emergence of pleural effusion ipsilateral or contralateral to the side drained previously is named recurrent effusion. There is currently no standart approach for the management of recurrent pleural effusions.

Materials and methods

Eighteen patients, treated between 2011 and 2012 for recurrent pleural effusions due to various etiologies, not considered for surgical or other treatments, and underwent placement of prolonged pleural catheters (Jackson-Pratt drain) were included in this study. Twenty two prolonged pleural catheters were inserted in 18 patients. There were 10 females and 8 males, with mean age 59 (35-77). In 20 patients the catheters were inserted by an anterior approach, and by a posterior approach in one patient. Daily drainage above 1,500 mL was not permitted in order to avoid pulmonary edema. Catheters were removed in patients who had lung expansion and drainage under 50 mL/day.

Results

The most common etiology for pleural effusions was extrathoracic malignancy in 9 patients, primary bronchial carcinoma in 5 patients, and benign pleural effusion in 4 patients. Four patients underwent bilateral prolonged pleural catheter insertion. The catheters were retained for a mean period of 19 (10-40) days. Pleural effusion recurred two months after removal of the catheter in one patient with primary bronchial cancer (5%). Only one patient developed a complication (empyema) while under drainage (5%). Two patients died while the catheter was in place.

Conclusions

Decreased length of stay and lower costs have enabled prolonged are the major advantages of pleural catheter applications in appropriate patients compared to other treatment methods. We believe that the Jackson Pratt silicone flat drains provide effective pleurodesis along with easy application, and suggest their use as an alternative to pleurodesis in especially malignant pleural effusions and not benign pleural effusions.KEY WORDS : Pleural effusion, prolonged pleural catheter, pleurodesis  相似文献   
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Nigella sativa oil (NSO), a herbaceous plant, has been used for thousands of years for culinary and medical purposes. This study aimed to investigate the anticonvulsant and antioxidant activities of NSO on pentylenetetrazol (PTZ) kindling seizures in mice. Nigella sativa oil was tested for its ability (i) to suppress the convulsive and lethal effects of PTZ in kindled mice (anti-epileptogenic effect), (ii) to attenuate the PTZ-induced oxidative injury in the brain tissue (antioxidant effect) when given as a pretreatment prior to each PTZ injection during kindling acquisition. Valproate, a major antiepileptic drug, was also tested for comparison. Both substances studied significantly decreased oxidative injury in the mouse brain tissue in comparison with the PTZ-kindling group. Nigella sativa oil was found to be the most effective in preventing PTZ-induced seizures relative to valproate. Nigella sativa oil showed anti-epileptogenic properties as it reduced the sensitivity of kindled mice to the convulsive and lethal effects of PTZ; valproate was ineffective in preventing development of any of these effects. The data obtained support the hypothesis that neuroprotective action of NSO may correlate with its ability to inhibit not only excessive reactive oxygen species (ROS) formation but also seizure generation.  相似文献   
108.
Nitric oxide as a physiopathological factor in neuropsychiatric disorders   总被引:8,自引:0,他引:8  
The dominant research subject on schizophrenia, mood disorders, autism and other central nervous system diseases has been related to neurotransmitter system abnormalities. For example, the dopamine hypothesis states that schizophrenia is the result of dopaminergic hyperactivity. The therapeutic approach has also been directed towards finding agents which will modulate or regulate these neurotransmitter systems at any step. There is substantial and mounting evidence that subtle abnormalities of reactive oxygen species (ROS) and nitric oxide (NO) may underlie a wide range of neuropsychiatric disorders. NO has chemical properties that make it uniquely suitable as an intracellular and intercellular messenger. It is produced by the activity of nitric oxide synthases which are present in peripheral tissues and in neurons. On the other hand, NO is known to be an oxygen radical in the central and peripheral nervous systems. NO has been implicated in a number of physiological functions such as noradrenaline and dopamine releases, memory and learning and certain pathologies such as schizophrenia, bipolar disorder and major depression. Evidence has been considered here for the proposal that an abnormality of NO metabolism may be a contributory factor in some neuropsychiatric disorders. The direct evidence for NO abnormalities in schizophrenia and other psychiatric disorders remains relatively limited to date, although there are some clinical and experimental studies. The suggestion that NO and other ROS may play a role in some neuropsychiatric disorders clearly has important implications for new treatment possibilities. The primary objective of the present review was to summarize and critically evaluate the current knowledge regarding a potential contribution of NO to the neuropathophysiology of schizophrenia as well as other neuropsychiatric disorders.  相似文献   
109.
This study investigated the fracture-healing effects of α-lipoic acid (α-LA), which was applied orally once daily in preventive treatment mode during 1 month after fracture induction. Rats were randomly divided into sham-operated group (group 1), femoral fracture control (group 2), femoral fracture?+?25 mg/kg α-LA (group 3), and femoral fracture?+?50 mg/kg α-LA (group 4). Rats in the experimental groups were orally administered 25 or 50 mg/kg α-LA once daily for 30 days starting from postoperative day 1. Thirty days postoperatively, the rats underwent X-ray imaging and were then euthanized for blood and tissue collection. Histopathological, biochemical, molecular, computed tomography (CT), and mechanical strength tests were performed on samples. The serum levels of osteocalcin (OC), osteopontin (OP), tumor necrosis factor alpha (TNF-α), and interleukin-6 (IL-6) did not differ significantly between groups 2 and 3. Serum OC, OP, TNF-α, and IL-6 levels in group 4 were significantly lower than those in group 3. From X-ray images, staging for fracture healing was scored as <2 in group 2, >2 in group 3, and >3 in group 4. In group 2, the average score of less than 2 suggests insufficient fracture healing; those of both the α-LA groups were >2, indicating progression of healing. Transforming growth factor beta (TGF-β) messenger RNA (mRNA) levels were significantly higher in the sham group than in the femoral fracture control. Both doses of α-LA increased TGF-β mRNA expression compared to the fracture group. CT results and biomechanical testing at 4 week after fracture demonstrated that α-LA has fastened bone healing, which was confirmed by stereological analyses in which 50 mg/kg α-LA increased the number of osteoclasts. Our findings indicate that α-LA supplementation promotes healing of femoral fractures in rats.  相似文献   
110.
Psychiatric disorders due to quinacrine for antiparasitic therapy represent an infrequent, but serious, complication. The remarkable course of a 12-year-old boy with common variable immunodeficiency who developed severe psychiatric reactions following quinacrine therapy for his resistant chronic giardiasis is presented. The broad clinical spectrum of quinacrine-associated neuropsychiatric disturbances has been emphasized for the clinicians.  相似文献   
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