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91.
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Visual perceptual and working memory impairments in schizophrenia   总被引:10,自引:0,他引:10  
BACKGROUND: Impairments in working memory have been proposed to underlie a broad range of cognitive deficits seen in schizophrenia. Visual working memory impairments are frequently reported in schizophrenia. Investigations of visual working memory generally assume intact visual information processing, despite evidence of visual perceptual impairments in schizophrenia. In this study, we evaluated the integrity of the perceptual system for object and spatial visual information and the relevant working memory system, after adjusting for individual perceptual performance differences. METHODS: Thirty patients with schizophrenia and 20 healthy control subjects underwent testing using a task of perceptual discrimination of spatial and object visual stimuli. For testing visual working memory, a delay was introduced to the perceptual discrimination task. A thresholding procedure was used so that each subject adequately perceived the information during the working memory test. RESULTS: Subjects with schizophrenia exhibited impaired performance relative to controls for object and spatial visual perceptual discrimination. The extent of impairment was greater for the object than for the spatial test. After controlling for perceptual impairments, the subjects with schizophrenia exhibited impaired performance relative to controls for the spatial working memory test but not the object working memory test. CONCLUSIONS: Findings implicate dysfunction of posterior brain areas that mediate visual perceptual processing and the prefrontal areas involved in the active maintenance of information during delay intervals. However, the systems that govern object and spatial visual perception and working memory appear to be affected differentially by schizophrenia.  相似文献   
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The aim of this study was to assess whether a femoral component which retained the neck reduced the incidence of leg-length inequality following total hip arthroplasty. A retrospective review was undertaken of 130 consecutive primary total hip arthroplasties performed between April 1996 and April 2004 using such an implant. There were 102 suitable patients for the study. Standardised pre- and post-operative pelvic radiographs were measured by an independent investigator to the nearest millimetre. The leg-length inequality was reduced from a mean pre-operative value of -0.71 cm to a mean of 0.11 cm post-operatively. Of the 102 patients 24 (23.5%) had an equal leg-length post-operatively, and 95 (93.1%) had a leg-length inequality between -1 cm and 1 cm.  相似文献   
95.
The vitamin D receptor (VDR) was the first candidate gene to be studied in relation to osteoporosis, and most attention has focused on polymorphisms situated near the 3′ flank of VDR. The aim of this study was to investigate the association about VDR gene Apa I polymorphism with bone mineral density (BMD) in postmenopausal women with osteoporosis. We studied a total of 136 postmenopausal women with a mean age of 56.36 ± 10.29 years. Among them, a total of 75 had osteoporosis, 37 had osteopenia, and 24 had normal BMD. Venous blood samples were obtained for evaluation of bone metabolism and genotyping. The VDR Apa I genotype was determined by polymerase chain reaction-restriction fragment length polymorphism. BMDs at the lumbar spine and hip were measured by dual-energy X-ray absorptiometry. Postmenopausal women with aa genotype had significantly lower BMD values (grams per centimeter square) at lumbar spines compared to persons with AA genotype. Also, postmenopausal women with AA genotype had significantly higher serum Ca level than the subjects with aa genotype. In conclusion, our result may indicate that VDR Apa I gene polymorphism may be responsible for a important part of the heritable component of lumbar spine BMD in postmenopausal women, possibly related to impaired calcium absorption from the bowel.  相似文献   
96.
We evaluated the incidence and risk factors of resistant Escherichia coli infections after the prostate biopsy under flouroquinolone prophylaxis. From January 2003 to December 2012, we retrospectively evaluated the records of 2215 patients. The risk factors were described for infective complications and resistant E. coli in positive cultures was calculated. Of 2215 patients, 153 had positive urine cultures, such as 129 (84·3%) E. coli, 8 (5·2%) Enterococcus spp., 6 (3·9%) Enterobacter spp., 5 (3·2%) Pseudomonas spp., 3 (1·9%) MRCNS, and 2 (1·3%) Klebsiella spp. Of the positive urine cultures which yielded E. coli, 99 (76·7%) were evaluated for fluoroquinolone resistance. Of those, 83 (83·8%) were fluoroquinolone-resistant and composed of 51 (61·4%) extended-spectrum beta-lactamase (ESBL)-positive. Fluoroquinolone-resistant E. coli ratios were 73·4 and 95·9% before 2008 and after 2008, respectively (P?=?0·002). The most sensitive antibiotics for fluoroquinolone-resistant E. coli strains were imipenem (100%), amikacin (84%) and cefoperazone (83%). The use of quinolones in the last 6 months and a history of hospitalization in the last 30 days were found to be significant risk factors. We found that resistant E. coli strains might be a common microorganism in patients with this kind of complication. The risk factors for development of infection with these resistant strains were history of the use of fluoroquinolones and hospitalization  相似文献   
97.
OBJECTIVE AND BACKGROUND: Determining the aetiology of an effusion involves assessing if it is an exudate or a transudate. However, a reliable test for determining the aetiology of a pleural effusion is lacking. Pleural viscosity has a high sensitivity and specificity and a high positive and negative predictive value for discriminating exudative and transudative pleural effusions. The aim of this study was to use pleural fluid viscosity to discriminate between various aetiologies of exudative effusions, namely malignant, parapneumonic and tuberculous. METHODS: Seventy consecutive patients (24 women, 46 men, mean age = 67 years) with exudative pleural effusion due to pneumoniae in 24 patients, tuberculous pleurisy in 21 and lung cancer in 25 were studied prospectively. Measurements of pleural fluid and plasma viscosity were performed using Brookfield DV-II viscometer. RESULTS: Pleural viscosity and pleural LDH were highest in the tuberculous pleurisy patients and lowest in the lung cancer patients. Pleural viscosity > or = 1.57 was found to be indicative of tuberculous pleurisy with a sensitivity of 100% and specificity of 95%. Pleural viscosity < 1.39 was found to be indicative of lung cancer with a sensitivity of 100% and specificity of 94%. Pleural viscosity was significantly correlated with pleural albumin (r = 0.34, P = 0.004), protein (r = 0.40, P = 0.001), LDH (r = 0.70, P < 0.001) and plasma viscosity (r = 0.44, P < 0.001), having the most significant value with pleural LDH. CONCLUSION: The pleural fluid viscosity of patients with parapneumonic, tuberculous and malignant effusions are significantly different from each other. Among these groups, tuberculous effusions had the highest viscosity, and malignant effusions from lung cancer the lowest.  相似文献   
98.
OBJECTIVE: Chlamydia pneumoniae and Mycoplasma pneumoniae are among the most important pathogens of acute respiratory infections in children between the ages of 5 and 15 years. We aimed to investigate seasonal frequency of respiratory infections caused by C. pneumoniae and M. pneumoniae, frequency of coinfection, clinical findings and to determine relationship between clinical findings and laboratory results. MATERIAL AND METHODS: Total of 284 patients (ranging 5-15 years of age), admitted to out-patient clinic with symptoms of respiratory tract infections between January 2004 and June 2005, were enrolled in the study. IgA, IgG and IgM antibodies against C. pneumoniae were quantitatively detected in all serum samples by using microimmunofluorescence (MIF). For the M. pneumoniae infection an IgM titer in the ELISA test were analyzed. Nasopharyngeal smear samples were collected for PCR detection. RESULTS: Mean age was 8 +/- 2.2 (range 5-14) years. Mycoplasma pneumoniae IgM in 86 (30.2%) cases, C. pneumoniae IgM in one (0.3%) case, IgA in six (2.1%) cases and IgG in 10 (3.5%) cases were found positive. In 10 (3.5%) cases, both C. pneumoniae IgG (a titer of >1/216) and M. pneumoniae IgM were found positive concomitantly. The M. pneumoniae IgM in winter was found significantly higher compared to other seasons. Mycoplasma pneumoniae PCR method was performed on a total of 203 samples in 33 (16.2%) of which M. pneumoniae was found positive. The false positive ratio of PCR technique was found 16.2%. In a total of 217 examined samples by PCR method, the DNA of C. pneumoniae was found positive in two patients. CONCLUSION: Mycoplasma pneumoniae was a common pathogen in respiratory infections. The otherwise C. pneumoniae infections were rarely seen in children. A Comparison of serology diagnostic tests for M. pneumoniae infections was found more sensitive and specific than PCR.  相似文献   
99.
Fetal malnutrition is an important risk factor for both early and late neonatal outcome and adult diseases. In this study, we aimed to investigate the incidence and characteristics of fetal malnutrition and its impacts on early neonatal morbidity and mortality in preterm infants by using the clinical assessment of nutritional status score (CANSCORE). Preterm infants whose gestational ages were between 28-34 weeks were included in the study. Detailed prenatal and natal history, anthropometric measurements, and intrauterine growth status were defined, and CANSCORE was applied to all infants. Infants were separated into two groups according to total score as malnourished (total score < 25) and well nourished (total score > or = 25). Early and late neonatal morbidities, which were observed during the clinical progress, were noted in all infants. A total of 93 preterm infants were enrolled in the study. The incidence of fetal malnutrition was 54.8% (n = 51) in all infants. The incidences of maternal hypertension and preeclampsia, oligohydramnios and disturbed umbilical artery Doppler flow in the prenatal period and the incidences of neonatal hypoglycemia, polycythemia, feeding intolerance, and necrotizing enterocolitis in the postnatal period were significantly higher in preterm infants with fetal malnutrition. Fetal malnutrition contributes significantly to many early and late neonatal morbidities in preterm infants, and it should be identified in every preterm infant in the first days of life for predicting neonatal outcome, even though they are appropriately grown.  相似文献   
100.
ObjectivesIt has been shown that blood pressure (BP) values measured in obese subjects are higher than the individuals with normal weight, even in normotensive limits. However, data concerning the Ambulatory Arterial Stiffness Index (AASI) and blood pressure load in normotensive obese subjects is lacking. This study was aimed to compare the ambulatory arterial stiffness index and blood pressure load in normotensive obese and healthy controls.MethodsOne hundred normotensive obese and one hundred normal weight subjects were included in this study. All subjects underwent 24-hour ambulatory blood pressure monitoring. Ambulatory arterial stiffness index was calculated from 24-hour ambulatory blood pressure monitoring records. Ambulatory arterial stiffness index was defined as one minus the regression slope of unedited 24-h diastolic on systolic blood pressures. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) load values were calculated from 24-hour ambulatory blood pressure monitoring analysis.ResultsAmbulatory arterial stiffness index of the obese subjects was significantly higher than the healthy controls (0.48±0.2 vs. 0.33±0.11, p<0.001). 24-hours systolic blood pressure and diastolic blood pressure loads were significantly higher in obese subjects. Logistic regression analysis revealed that body mass index (BMI) was an independent predictor for an abnormal ambulatory arterial stiffness ındex (≥0.50) (OR: 1.137, 95% CI: 0.915-1.001, p=0.004).ConclusionBlood pressure load and ambulatory arterial stiffness index are increased in normotensive obese patients. Moreover, body mass index is an independent predictor for an abnormal ambulatory arterial stiffness index. Our results indicate that obese subjects are at higher risk for future cardiovascular events despite normal office BP levels.  相似文献   
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