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51.
Chromium, a major environmental pollutant, is known for its wide toxic manifestations. The present experiment pertains to the protective role of selenium (Se) against K2Cr2O7-induced hepatotoxicity. Female Wistar rats were divided into four groups of six each: group I served as controls which received standard diet; group II received in drinking water K2Cr2O7 alone (700 ppm); group III received both K2Cr2O7 and Se (0.5 Na2SeO3 mg/kg of diet); group IV received Se (0.5 mg/kg of diet) for 3 weeks. Exposure of rats to chromium promoted oxidative stress with an increase in malondialdehyde (MDA) and a decrease in glutathione (GSH) levels. A decrease in glutathione peroxidase (GPx) and an increase in superoxide dismutase (SOD) and catalase (CAT) activities were observed. Se supplementation to the diet of group III improved all the parameters cited above. Yet, plasma transaminases (AST and ALT), lactate dehydrogenase (LDH) activities, cholesterol, triglycerides (TG) and low density lipoprotein-cholesterol (LDL-C) levels increased, while high density lipoprotein-cholesterol (HDL-C) decreased. Co-administration of Se to the diet of group III restored hepatic markers to near-normal values. The biochemical results confirmed the histopathological findings. Therefore, our investigation revealed that Se was effective in preventing K2Cr2O7-induced hepatotoxicity.  相似文献   
52.
This study investigated the hypoglycemic and antioxidant effects of Flax and Pumpkin seeds mixture on the kidney of alloxan-induced diabetic rats. Animals were allocated into three groups of six rats each: a control group (CD), a diabetic group (DD) and diabetic rats fed with Flax and Pumpkin seeds mixture (DMS) group. The DD rats showed a significant increase of glycemia and lipid parameters such as total lipid, total cholesterol and triglycerides levels compared to those of the control group (CD). In addition, plasma and kidney malonaldialdehyde levels (MDA) were significantly increased compared to (CD) group. Antioxidant enzyme activities such as catalase (CAT), superoxide dismutase (SOD) and non-enzymatic levels of reduced glutathione (GSH) significantly decreased in the plasma and kidney of diabetic rats compared to those of controls. Diet supplemented with Flax and Pumpkin seeds mixture ameliorated the antioxidant enzymes activities observed in diabetic rats and significantly decreased MDA levels. Kidney histological sections, showed glomerular hypertrophy and tubular dilatation. In DMS rats, these histopathological changes were less prominent. Our results suggest that Flax and Pumpkin seeds mixture supplemented in diet of diabetic rats may be helpful to prevent diabetes and its complications.  相似文献   
53.
The tongue is often considered a key innovation in the evolution of a terrestrial lifestyle as it allows animals to transport food items through the oral cavity in air, a medium with low density and viscosity. The tongue has been secondarily coopted for a wide diversity of functions, including prey capture, drinking, breathing, and defensive behaviors. Within basal lizard groups, the tongue is used primarily for the purpose of prey capture and transport. In more derived groups, however, the tongue appears specialized for chemoreceptive purposes. Here we examine the tongue structure and morphology in lacertid lizards, a group of lizards where the tongue is critical to both food transport and chemoreception. Because of the different mechanical demands imposed by these different functions, regional morphological specializations of the tongue are expected. All species of lacertid lizards examined here have relatively light tongue muscles, but a well developed hyobranchial musculature that may assist during food transport. The intrinsic musculature, including verticalis, transversalis, and longitudinalis groups, is well developed and may cause the tongue elongation and retraction observed during chemoreception and drinking. The papillary morphology is complex and shows clear differences between the tongue tips and anterior fore-tongue, and the more posterior parts of the tongue. Our data show a subdivision between the fore- and hind-tongue in both papillary structure and muscular anatomy likely allowing these animals to use their tongues effectively during both chemoreception and prey transport. Moreover, our data suggest the importance of hyobranchium movements during prey transport in lacertid lizards.  相似文献   
54.

Background

The treatment of the symptomatic pilonidal sinus is surgical with one of the most extensive being excision of the diseased tissue down to the sacral fascia. The closure of the defect is the matter of debate. An elliptical rotation flap has been used for pilonidal sinus treatment with no recurrence rate.

Methods

From April 1996 to June 2001, 20 patients were treated with this technique. The surgical procedure is a vertical elliptical excision of the diseased tissue and an elliptical cutaneous rotation flap to close the defect.

Results

Twenty patients underwent with this technique, mean age 23.4 years (range 18 to 34). Mean follow-up was 42 months. All patients were discharged on the first postoperative day. Primary healing was achieved in all of the patients in 2 weeks. No recurrence was observed.

Conclusions

Elliptical rotation flap is recommended for patients selected for defect closure. It offers improved patient comfort, shorter hospital stay, and no recurrence rate.  相似文献   
55.
Potassium dichromate (K2Cr2O7) is an environmental contaminant widely recognized as a carcinogen, mutagen, and teratogen toward humans and animals. This study investigated the effects of K2Cr2O7 on the hepatic function of pregnant and lactating rats and their suckling pups. Experiments were carried out on female Wistar rats given 700 ppm of K2Cr2O7 in their drinking water from the 14th day of pregnancy until day 14 after delivery. Hepatotoxicity was objectified by the significant increase in liver malondialdehyde content and a significant accumulation of chromium in this soft tissue. Moreover, exposure to K2Cr2O7 induced a decrease of glutathione, nonprotein thiols, and vitamin C in the liver of mothers and their suckling pups. Alteration of the antioxidant system in the treated group was confirmed by the significant decline of antioxidant enzyme activities such as catalase, glutathione peroxidase, while liver superoxide dismutase activity increased in mothers and decreased in their offspring. It was found that K2Cr2O7 induced liver damages as evidenced by the elevation of plasma aminotransferases, lactate dehydrogenase activities, and bilirubin levels. Impairment of the hepatic function corresponded histologically. Our investigation revealed hemorrhage, leukocytes infiltration cells, and necrosis, which were more pronounced in the hepatocytes of mothers than in those of their suckling pups. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2013.  相似文献   
56.
Intellectual Deficiency (ID) is a common neuropsychiatric disorder whose etiopathogenesis still insufficiently understood. In the last decade, several surveys, assessing epidemiologic, clinical and etiologic parameters of ID, have been performed but none of them is realized in a Tunisian population. In this retrospective survey, we propose to study these parameters, in a Tunisian cohort of 458 patients with constitutional ID, and to assess our diagnostic strategy. Data analyses, by the SPSS program, reveal a male predominance, a high level of consanguinity, an advanced mean age of patients, a rare frequentation of specialized institutions by the severely affected patients, and a high frequency of familial forms with predominance of the recessive autosomal ones. The study of clinical parameters and investigations' results shows that 72.1% of our patients present a syndromic ID. For these patients, chromosomal anomalies are rarely described, EEG anomalies were usually non-specific in patients without clinical evidence of epilepsy, and brain anomalies are common in patients with severe ID, neurological symptoms or history of seizures. Aetiology is identified in 13.1% of them whereas it is still unknown in 100% of patients with non-specific ID. This study allows us to better characterize, epidemiologically and clinically, the first large Tunisian cohort of patients with ID and to assess our diagnostic strategy in order to propose a revised one that will improve the diagnostic lead, the care chain and the preventive resources of ID.  相似文献   
57.

Introduction

Bovine teeth are commonly used as substitutes for human teeth in scientific investigations. The present study was performed in vitro with the objective of comparing bovine and human enamel subjected to thermocycling for microleakage beneath metal brackets.

Materials and methods

A total of 50 bovine and human teeth (25 per group) void of defects or carious decay were extracted and stored in chloramine B (0.5%). A light-curing adhesive (Transbond? XT) was used as instructed by the manufacturer (3M Unitek, Monrovia, CA, USA) to bond a metal bracket (discovery®; Dentaurum, Ispringen, Germany) to the surface of each tooth following 30 s of enamel etching (phosphoric acid 35%). After 24 h of dye penetration in methylene blue (0.5%), the cervical and incisal bracket surfaces were analyzed by light microscopy for excess bonding material, dye penetration, and microleakage at the bracket–adhesive and adhesive–enamel interfaces. Staining and evaluation was repeated after thermocycling (5000 cycles at 5/55 °C).

Results

Before thermocycling, the number of human teeth showing marginal gaps was one-third the number of bovine teeth (p<0.001). After thermocycling, the distribution of gaps was similar (p=0.180). The adhesive–enamel interface was most frequently affected (on 74% of human and 64% of bovine teeth). No dye penetration in either group after examining a horizontal slice through the bracket basis was observed.

Conclusion

Immediately after bonding, less microleakage was observed around the base of metal brackets on human than bovine teeth. These marginal gaps were, however, superficial in both groups, none of them involving deep penetration of dye under the bracket base.  相似文献   
58.
Although successful hematopoietic stem cell transplantation (HSCT) can offer a cure in thalassemia major, there are only a few and noncomprehensive studies of its effect on the quality of life (QoL), as it is expected to increase the QoL by ending transfusion-related issues. Our objective was to compare the health-related quality of life (HRQoL) of transplanted and nontransplanted thalassemia major patients in a developing country. We have studied the QoL effect of HSCT in consecutively invited 50 nontransplanted and 49 transplanted patients who had received transplants from HLA matched related donors at least two years ago. PedsQL questionnaire was used for the patients under 18?years of age and World Health Organization's WHOQoL-BREF questionnaire for above 18?years of age. Higher QoL was determined in HSCT performed group surveyed in 5-18?years' age group. Detailed analysis marked the profound difference in 8-12 year subgroup, particularly in physical activity questionnaires. QoL scores in HSCT performed adult group are higher than the transfusion-dependent group, especially in physical activity domain. Transplanted adult patients rated their overall health significantly better than patients on conventional therapy. The patients who still have chronic graft versus host disease rated worse compared to those without it. In conclusion, thalassemia major patients who have undergone HSCT at least two years before assessment are not inferior to the transfusion-dependent group with regard to the QoL and have a better QoL than transfusion-dependent patients in some areas. The QoL score is better for school children and adolescents; therefore, we suggest HSCT before primary school. GVHD reduces the QoL significantly and it is obvious that GVHD prevention should be one of the primary goals of post-HSCT follow-up.  相似文献   
59.
Brown tumors are rare skeletal manifestations of hyperparathyroidism (HPT) that may mimic cancer metastasis. Here, we present a 52-year-old woman with HPT and multiple foci of technetium uptake due to brown tumors on bone scintigraphy. Screening tests were negative for cancer and serum parathormon (PTH) measurement; parathyroid ultrasonography and scintigraphy suggested HPT. A chief cell adenoma in right and hyperplasia in the left parathyroid glands were surgically removed after which hungry bone syndrome emerged. Biopsy of the femur lesion during an open reduction with fixation operation due to a fracture established the diagnosis of a brown tumor. Brown tumors are important to consider in the evaluation of patients presenting with multiple foci of uptake on bone scanning and without an established primary neoplasm.  相似文献   
60.
Abstract   Objective: Risk factors and results of cardiac surgery with cardiopulmonary bypass (CPB) in hemodialysis-dependent renal failure patients at our center were evaluated. Methods: Out of 16,425 patients undergoing open heart surgery with CPB at our center between January 1991 and April 2006, 91 (0.6%) experienced hemodialysis-dependent end-stage renal failure. Preoperative, operative, and postoperative findings of two groups of patients were evaluated: those with normal renal function (control group) and those with chronic renal failure undergoing regular hemodialysis (HDRF group). Survival analyses of the hemodialysis group of patients were performed. Results: In the hemodialysis group, 54 (59.3%) patients underwent coronary artery surgery, 31 (34.1%) patients had valve surgery, four (4.4%) patients had aortic surgery, and two others (2.2%) experienced concomitant coronary and peripheral artery surgery. CPB and aortic cross-clamping (ACC) times were longer in the HDRF group (p = 0.000 and 0.002, respectively). There was no significant difference between the two groups with regard to either reoperations, infections, pulmonary and gastrointestinal system complications, or cerebrovascular event parameters (p = 0.167, 0.341, 1.000, 1.000, and 1.000, respectively). There was no difference between groups in the postoperative development of low cardiac output (p = 0.398). The early mortality rate was 7.7% (seven patients) in the HDRF group and 4.8% (780 patients) in the controls (p = 0.211). The actuarial survival rates in HDRF survivors at one, two, three, four, five, and ten years were overall 86%, 80%, 68.1%, 45.4%, 20%, and 6.8%, respectively. Conclusions: Open heart surgery in hemodialysis patients is associated with a higher incidence of risks, but can be performed with acceptable operative complications and mortality with an effective hemodialysis program.  相似文献   
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