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51.
Vascular access thrombosis is a leading cause of vascular access failure in hemodialysis patients. Thrombosis is a multifactorial condition and genetic makeup can affect thrombosis risk. We conducted a study to investigate for possible associations between ecNOS gene intron 4 variable-number tandem repeat (VNTR) polymorphism and thrombosis of polytetrafluoroethylene hemodialysis arteriovenous access grafts (AVG) in Turkish patients. Fifty-five patients with end-stage renal disease who had AVGs implanted between 2000 and 2002 and 167 healthy individuals representing our healthy population were enrolled in this prospective study. Each subject provided a venous blood sample from which DNA was isolated, and polymerase chain reaction analysis was done to identify genotypes (aa, bb, ab) for ecNOS gene intron 4 VNTR polymorphism. All grafts were placed in brachioaxillary position. The subjects were divided into two groups based on duration of graft patency. The thrombosis group (Group I) comprised 26 patients who developed AVG thrombosis in the first 12 months after placement. The no-thrombosis group (Group II) comprised 29 patients whose grafts remained patient for at least 12 months. The frequency of the aa genotype in Group I was significantly higher than that in Group II (p = .005). At 6, 12, and 24 months, the primary patency rates for the AVGs in patients with the aa genotype were significantly lower than the corresponding rates for the bb and ab genotype groupings (p = .01, p = .01 and p = .04 for the three respective time points; Kaplan-Meier). ecNOS gene intron 4 VNTR polymorphism is linked with the pathogenesis of vascular access thrombosis in Turkish patients undergoing hemodialysis.  相似文献   
52.
Background: Review of the literature clearly reveals that little is known about the association between functional and mental status, and Lower Urinary Tract Dysfunction (LUTD) in patients with stroke.

Objective: The aim of this study was to assess functional and mental status in stroke patients and to identify possible associations with the prevalence, severity and bother of LUTD.

Material and methods: This study was designed as a cross-sectional study and included 260 stroke patients enrolled from six different hospitals in Turkey. The patients were questioned using the Danish Prostatic Symptom Score (DAN-PSS) Questionnaire to evaluate LUTD, and evaluated using the Modified Barthel Index (MBI), Incontinence Quality of Life Questionnaire (I-QoL), and the Mini Mental State Examination (MMSE).

Results: At least one LUTD finding was reported in 243 (93.5%) patients; the most commonly encountered complaint in these patients was nocturia (75.8%). The mean MBI, MMSE, and I-QoL scores were found to be significantly lower in LUTD (+) patients compared to LUTD (?) patients (p = 0.000, p = 0.005, and p < 0.01, respectively). Similarly all parameters (MBI, MMSE, and I-QoL scores) assessed were found to be significantly lower for patients with urinary incontinence than those without incontinence (p = 0.000, p = 0.000, and p < 0.01, respectively).

Conclusion: LUTD is a common problem in patients with stroke. LUTD is associated with poorer cognitive and functional status and the quality of life in these patients. We, therefore, suggest that bladder dysfunction should not be overlooked during rehabilitation of stroke patients.  相似文献   

53.
BACKGROUND AND AIMS: Non-steroidal anti-inflammatory drug (NSAID) use has been closely associated with an increased risk of bleeding peptic ulcers, while the prevalence of Helicobacter pylori infection has been reported to be lower in bleeding ulcers than in non-bleeding ones. However, whether an interaction exists between NSAID use and H. pylori infection has not clearly been elucidated yet. The aims of this study were to determine the frequency of NSAID use and H. pylori infection, to predict risk factors in bleeding peptic ulcers and to determine whether NSAID use and H. pylori infection interact with each other. METHODS: Ninety-six patients with bleeding ulcer were included in the study. The control group consisted of 106 patients with non-bleeding ulcer. Data were analyzed by using the chi-squared test, Fisher's exact test and logistic regression analysis with or without interaction term (H. pylori by NSAID). RESULTS: Non-steroidal anti-inflammatory drug use was significantly more common in patients with bleeding ulcers than in controls (79.2 vs 38.7%, unadjusted odds ratio (OR): 6.02, 95% confidence interval (CI): 3.21-11.29). The frequency of the H. pylori infection was significantly lower in patients with bleeding ulcers than in controls (66.7 vs 89.6%, unadjusted OR: 0.23, 95% CI: 0.10-0.49). In the logistic regression analysis with the interaction term, male sex (adjusted OR: 3.70, 95% CI: 1.65-8.29), multiplicity of ulcers (adjusted OR: 4.10, 95% CI: 1.02-16.45) and NSAID use (adjusted OR: 33.87, 95% CI: 4.36-262.97) were independent risk factors for bleeding ulcers. There was a negative interaction between H. pylori and NSAID use (adjusted OR: 0.09, 95% CI: 0.01-0.83). CONCLUSIONS: The negative interaction between the two variables suggests that the presence of H. pylori is associated with a lower risk of bleeding in ulcer patients taking NSAIDs.  相似文献   
54.
In this study, we investigated some of the prothrombothic mutations and polymorphisms in 15 children with congenital cardiac malformations who developed severe thrombosis in the perioperative period following surgical repair. The mutations and polymorphisms included in the study were Factor V Leiden, prothrombin G20210A, methylentetrahydrofolate reductase C677T, endothelial nitric oxide synthase intron 4 VNTR, alpha-fibrinogen Thr312Ala, Factor XIII Val34Leu, and insertion or deletion of angiotensin 1 converting enzyme. Compared to the healthy Turkish subjects, our patients had a similar rate of mutation of Factor V Leiden, Factor XIII Val34Leu, and endothelial nitric oxide synthase a/b polymorphisms, but higher frequency of the prothrombotic angiotensin 1 converting enzyme deletion/deletion genotype, and lower frequency of the antithrombotic alpha fibrinogen Thr/Thr genotype. None of the patients exhibited mutations involving prothrombin G20210A or methylentetrahydrofolate reductase C677T. The results of our study suggest that, in addition to prothrombotic mutations such as Factor V Leiden, single-nucleotide polymorphisms should be considered in all children with congenital cardiac malformations who develop thrombosis. Malformations of the heart are the most common of all serious lesions that are present at birth, with an incidence of 4 to 8 cases per 1,000 live births. If needed, corrective surgery is usually the optimal treatment for these anomalies, but perioperative morbidity and mortality still remain high due to several factors. Arterial or venous thrombosis, or both varieties of thrombosis, is among these factors. Prior to surgery, the most frequent time at which these children develop thrombosis is during cardiac catheterization. Postoperative thrombosis in this group of patients is a more complex disorder, which can affect both small and large vessels, and is associated with a high morbidity and mortality. Recent studies indicate that both point mutations and single-nucleotide polymorphisms of genes that encode proteins involved in the coagulative and anticoagulative cascades are important risk factors for development of thrombosis. Patients with these risk factors are most likely to develop thrombosis when triggering elements, such as placement of catheters, prolonged immobilization, or surgery, are also present. In this study, we investigated some of the above-mentioned mutations and polymorphisms in children who developed thrombosis in the perioperative period after correction of congenital cardiac malformations.  相似文献   
55.
Metabolic Brain Disease - 6-Hydroxydopamine (6-OHDA) is a widely used chemical to model Parkinson’s disease (PD) in rats. Syringic acid (SA) is a polyphenolic compound which has antioxidant...  相似文献   
56.
BACKGROUND: Invasive aspergillosis is a challenge to the internist, and difficulties diagnosing the disease remain an everlasting problem. METHODS: We reviewed the data of 65 patients with hematological malignancies and aplastic anemia who were tested for the galactomannan (GM) antigen of Aspergillus between March and November 2003. RESULTS: GM antigen levels were false-positive in at least two consecutive samples in 5 out of 23 patients who did not have evidence of invasive aspergillosis (false positivity rate of 21.7%) but who received concomitant piperacillin/tazobactam (P/T) compared to 0 of 28 patients who did not. DISCUSSION: The use of P/T in febrile, neutropenic patients decreases the specificity of GM antigen testing, which may lead to incorrect and unnecessary attempts at diagnosis and therapy.  相似文献   
57.
Different forms of Aluminium (Al) are environmental xenobiotics that induce free radical-mediated cytotoxicity and reproductive toxicity. Vitamin E (alpha -tocopherol) is an antioxidative agent that has been reported to be important for detoxification pathways. This study was thus aimed at elucidating the protective effects of vitamin E towards aluminium toxicity on the histology of the rat testis. Al (5 mg/kg body weight) was administered intraperitoneally in 2 ml saline, either alone or immediately before vitamin E (500 mg/kg body weight), at a different point of abdomen, and the alterations in the testis tissue were analyzed histologically. Seven treated animals were sacrificed for each group, with the testes removed and examined histologically. In the Al-treated group, the germinal epithelium of the seminiferous tubules was thinner in places and spermatids were almost absent; sperm numbers were low and there were no sperm in the lumen. In the Al plus vitamin E rats, there were large numbers of spermatids and sperm in the seminiferous tubule lumen. In the vitamin E alone group, a normal histology was seen. Electron microscopically, in the Al-treated group there were irregularities in the nuclear membrane, some damaged mitochondria, a decrease in the number of ribosomes, and an increase in the number of lysosomes in the sertoli cell cytoplasm. In the primary spermatocyte cytoplasm, there was an increase in the rough endoplasmic reticulum. In the Al plus vitamin E group, the spermatogeneic cells and the sertoli cell cytoplasm showed an almost normal appearance. The ultrastructure of the testis in the vitamin E alone group showed a normal appearance. In conclusion, vitamin E antagonizes the toxic effects of Al at the histological level, thus potentially contributing to an amelioration of the testis histology in the Al-treated rats. The associated biochemical parameters merit further investigation.  相似文献   
58.
59.
Obesity is associated with the changes of plasminogen activator inhibitor-1 (PAI-1), tumor necrosis factor-alpha (TNFalpha) and transforming growth factor beta (TGFbeta) levels. However, the precise effect of the 4G allele on obesity is still contradictory. Here, we aimed to elucidate the role of the 4G/5G polymorphism of the PAI-1 gene on the PAI-1 level and determine the associations between cytokines, glucose and lipid metabolism parameters in obese children. Thirty-nine obese children (mean age 11.4 +/- 3.3 years) and 38 age-matched healthy control group (mean age 10.3 +/- 3.5 years) were included in the study. In all cases, serum levels of glucose, lipid and insulin were measured, homeostasis model assessment of insulin resistance (HOMA-IR) was calculated, and 4G/5G polymorphism of PAI-1 gene, plasma PAI-1 level and serum TNFalpha and TGFbeta levels were studied. The mean relative body mass index (BMI) and HOMA-IR score, VLDL, TG, insulin, PAI-1, TNFalpha levels were higher, and HDL and TGFbeta levels were lower in the obese group. The frequency of the 4G/4G genotype was considerably higher in obese children than in controls. Also, a positive correlation was found between PAI-1 and TNFalpha levels, and relative BMI, HOMA-IR score, insulin, TG, HDL levels. TGFbeta was inversely correlated only with relative BMI. There was no correlation among three cytokines. In conclusion, childhood obesity contributes to higher PAI-1 and TNFalpha and lower TGFbeta levels. Especially PAI-1 and TNFalpha accompany insulin resistance and dyslipidemia.  相似文献   
60.
Pulmonary embolism (PE) is difficult to diagnose. We investigated the relationship between computed tomography pulmonary angiography (CTPA) with clinical assessments and thrombus localization. 56 patients with the suspicion of PE; 27 male, 29 female were included. They were evaluated by empirical and Wells clinical assessments, tested with D-Dimer. According to the combination of both CTPA was performed where necessary (if one of the clinical assessments was high or intermediate or those with low clinical probability and high D-Dimer) in the algorithm we used. CTPA was regarded as gold standard. Dyspnea, chest pain, tachypnea, crackles were the most common symptoms and signs in patients having PE. Recent surgery within the risk factors was significantly higher in the PE present group. PE was diagnosed in 31 (55.4%) patients with CTPA. According to the empirical assessment 20 (64.5%) of the patients had high, 10 (32.3%) had intermediate and 1 (3.2%) had low clinical probability within 31 PE present group, while with Wells scoring 8 (25.8%) had high, 17 (54.8%) had intermediate and 6 (19.4%) had low clinical probability. Sensitivity of the empirical assessment and Wells scoring was 97%, 80% while the specificity was 16%, 68% respectively. Positive and negative predictive values of empirical assessment were 59%, 80% and these values of Wells scoring were 76%, 73% respectively. Thrombus was localized in main pulmonary arteries in 45.8% of patients with high clinical probability according to the empirical assessment. With Wells scoring in 45.5% of the high probability patients and only in 4.3% of the low probability patients thrombus was there. PE can be diagnosed noninvasively. Since PE can easily be underdiagnosed, empirical assessment which is more sensitive will be appropriate. There is a significant correlation between clinical assessments and presence of PE in CTPA. As the severity of clinical assessment increases, thrombus settles more proximal.  相似文献   
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