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101.
Cell mediated immunity (CMI) in 15 patients with subacute sclerosing panencephalitis (SSPE) was assessed by E-rosette formation, leucocyte migration inhibition factor (LIF) production, and proliferative responses to mitogens. In eleven patients, one or more of these parameters were impaired. These defects varied among the different patients and no consistent or uniform pattern of immune deficiency could be demonstrated. Although no single patient had a generalized reduction of all the T-cell functions, a diminished percentage of E-rosetting cells was the most frequent abnormal parameter (7 out of 15 patients). There was no correlation between the clinical state of the patients and the immune defects. Thymic humoral factor (THF), a thymic hormone, reconstituted at least one CMI impaired function especially the reduced levels of E-rosette forming cells in 7 out of 9 patients. It seems unlikely that a generalized cell-mediated defect is the underlying cause of this disease, but immunomodulatory therapy should be considered in some selected cases.  相似文献   
102.
The aim of this study was to determine the impact of recently developed rapid radiometric techniques on the clinical diagnostic operations of a reference laboratory for mycobacteria. Selective inhibition by-nitro--acetylamino--hydroxypropiophenone was used to rapidly screen submitted cultures for identification of mycobacterial species other than Mycobacterium tuberculosis. The radiometric drug susceptibility test was applied only to those cultures presumptively identified as belonging to theMycobacterium tuberculosis complex. All referred cultures were tested without additional subculture. The results showed that non-pigmented mycobacteria other thanMycobacterium tuberculosis can be screened with about 99% reliability, most of them within 24 hours. Unnecessary drug susceptibility testing of mycobacteria other than tubercle bacilli can be avoided at an early stage, thus shortening the average reporting time of theMycobacterium tuberculosis complex to nine days following the receipt of the cultures. Ways of limiting erroneous reporting are discussed.  相似文献   
103.

Background

Aging and dyslipidemia are processes which can lead to deleterious consequences to renal function. Therefore, the aim of this study was to determine the effects of both hypercholesterolemia and aging on renal function in mice.

Methods

Male hypercholesterolemic apolipoprotein E-deficient mice (ApoE, n = 13) and age-matched C57BL/6 control mice (C57, n = 15) were studied at 2 (young) and 8 (adult) month-old. At each time point, animals were placed in metabolic cages for 24 hours to urine volume and urinary creatinine quantification. Blood samples were collected for serum cholesterol, urea and creatinine measurements. Glomerular filtration rate (GFR) was estimated through creatinine clearance determination. Mesangial expansion was evaluated by Periodic Acid Schiff staining, renal fibrosis was determined through Masson's trichrome staining and neuronal nitric oxide synthase (nNOS) expression in the kidney was performed by Western Blotting. To statistical analysis two-way ANOVA followed by Fisher's post hoc test was used.

Results

Total plasma cholesterol was increased about 5-fold in ApoE mice at both time points compared to C57 animals. At 2-month-old, GFR was already markedly reduced in ApoE compared to C57 mice (187 ± 28 vs 358 ± 92 μL/min, p < 0.05). Adult C57 (-77%) and ApoE (-50%) mice also presented a significant reduction of GFR. In addition, serum urea was significantly increased in young ApoE animals compared to C57 mice (11 ± 1.3 vs 7 ± 0.9 mmol/L, p < 0.01). A significant mesangial expansion was observed at 2-month old ApoE mice compared to C57 mice (35 ± 0.6 vs 30 ± 0.9%, respectively, p < 0.05), which was aggravated at 8-month old animals (40 ± 3 and 35 ± 3%, respectively). Tubulointersticial fibrosis was augmented at both young (17 ± 2%, p < 0.05) and adult (20 ± 1%, p < 0.05) ApoE mice compared to respective C57 age controls (8 ± 1 and 12 ± 2%, respectively). The expression of nNOS was markedly reduced in a time-dependent manner in both strains.

Conclusions

These data show that both hypercholesterolemia and aging contribute to the loss of renal function in mice.
  相似文献   
104.
An outbreak of hepatitis E virus (HEV) began in October 2007 in northern Uganda. To determine risk factors and sources for ongoing transmission, we conducted both a case-control study and an environmental investigation. A case patient was defined as having serologic evidence of HEV infection, whereas controls were seronegative. We identified risk factors for infection by univariable and multivariable analyses using conditional logistic regression. Several water sources were tested for HEV RNA. Among 112 cases and 145 controls, storage of drinking water in large-mouthed vessels (adjusted odds ratios [AOR] = 2.83; 95% confidence interval [CI] = 1.16-6.94) and washing hands in a group basin (AOR = 1.90; 95% CI = 1.07-3.38) were associated with HEV infection. HEV RNA was detected from communal hand-rinse and surface-water samples. The epidemiologic and environmental water-testing results suggest that household-level factors played an important role in the transmission of HEV-modalities that have been previously underappreciated.  相似文献   
105.
A recently developed method of drug susceptibility testing of Mycobacterium tuberculosis which measures the evolution of labeled CO2 from [1-14C]palmitic acid (BACTEC 460 system) was compared to three conventional methods. The proportion method of drug susceptibility testing was the standard against which all test results were compared. Indirect drug susceptibility to isoniazid, streptomycin, rifampin, and ethambutol of 245 isolates belonging to the M. tuberculosis complex was determined. In 95% of the cases, results obtained by the radiometric method were available within 1 week, as opposed to 3 to 6 weeks needed in conventional methodology. Overall agreement was 96.4%. Specificity values ranged from 0.98 to 1.0; sensitivity values of 1.0 for rifampin, 0.96 for streptomycin, 0.91 for isoniazid, and 0.18 for ethambutol were obtained. The specificity of the absolute concentration and resistance ratio drug susceptibility testing methods were 0.99 and 1.0, respectively. The sensitivity of the former was higher than that of the radiometric method (0.99 verus 0.92), whereas that of the latter was lower (0.88 verus 0.96). Further testing indicated that the low sensitivity determined for ethambutol may be due to the choice of the critical concentration used, rather than to a shortcoming of the procedure. The radiometric method thus does not significantly differ in reliability from conventional methods of drug susceptibility testing of M. tuberculosis.  相似文献   
106.
107.
Solitary fractures of the cuboid are rare. Proper diagnosis and treatment of subtle cuboid fractures are essential to minimize long-term disability and must begin with the appropriate clinical suspicion. Treatment of overt cuboid fractures has changed over time and now includes aggressive repair of the fracture. The authors provide an overview of cuboid fractures and report on a patient with a minimally displaced fracture who was treated conservatively.  相似文献   
108.
On October 15, 2001, a U.S. Senate staff member opened an envelope containing Bacillus anthracis spores. Chemoprophylaxis was promptly initiated and nasal swabs obtained for all persons in the immediate area. An epidemiologic investigation was conducted to define exposure areas and identify persons who should receive prolonged chemoprophylaxis, based on their exposure risk. Persons immediately exposed to B. anthracis spores were interviewed; records were reviewed to identify additional persons in this area. Persons with positive nasal swabs had repeat swabs and serial serologic evaluation to measure antibodies to B. anthracis protective antigen (anti-PA). A total of 625 persons were identified as requiring prolonged chemoprophylaxis; 28 had positive nasal swabs. Repeat nasal swabs were negative at 7 days; none had developed anti-PA antibodies by 42 days after exposure. Early nasal swab testing is a useful epidemiologic tool to assess risk of exposure to aerosolized B. anthracis. Early, wide chemoprophylaxis may have averted an outbreak of anthrax in this population.  相似文献   
109.

Background

Direct laryngoscopy and rigid bronchoscopy are currently performed using 2-dimensional endoscopic systems. Our objective was to determine whether a 3-dimensional endoscopic system can enhance visualization of the surgical field in pediatric direct laryngoscopy and rigid bronchoscopy.

Methods

A prospective cohort study was conducted. Thirty three children who underwent direct laryngoscopies in a tertiary referral children's hospital were enrolled. Direct laryngoscopy was performed using both 2- and 3-dimensional endoscopic systems, after which the surgeons scored the quality of the images obtained with each system on a scale from 1 (low) to 5 (high). Comparison of the scores obtained with the 2 endoscopic systems was performed.

Results

The 33 study children (mean age 2.3?years, M:F ratio 1:1.6) underwent 47 direct laryngoscopies. The mean score for visualization of the glottis was 4.8 for the three-dimensional system compared to 4.0 for the two-dimensional system (P?=?.025), 4.7 vs. 3.8, respectively, (P?=?.019) for the subglottis, and 4.6 vs. 3.9, respectively (P?=?.031) for visualization of the proximal trachea. The mean score for visualization of the distal trachea was 3.0 vs. 3.7, respectively (P?=?.020). In a child with recurrent type 3 laryngotracheal cleft a residual tracheo-esophageal fistula could not be detected using the 2D system, but was immediately detected using the 3D system.

Conclusions

Visualization of the glottis, subglottis and proximal trachea during direct laryngoscopy using a 3-dimensional endoscopic system was rated by the surgeons as being superior to the conventional 2-dimensional technique. Further outcome studies that will demonstrate the clinical advantage of the 3D technology are highly required.Level of evidence: 2b.  相似文献   
110.
A number of glycolipids were evaluated in an ELISA test for their serodiagnostic usefulness in tuberculosis. One hundred and twelve (112) sera belonging to bacteriologically confirmed TB patients, patients with pathologies other than tuberculosis and healthy individuals were examined against several synthetic "mirror" pseudo cord factors (analogues of trehalose-6,6'-dimycolate or TDM) using natural cord factor and another recently described natural glycolipid (SL-IV) of Mycobacterium tuberculosis as control antigens. Analysis of the results shows that all synthetic "mirror" pseudo cord factors, except one with a short 8-carbon chain, were better recognized by the sera of tuberculosis patients than natural cord factor, with sensitivity and specificity values in the ELISA test similar to those reported for M. tuberculosis species-specific SL-IV. Of all antigens tested in this study, BDA. TDA, a bis(N,N-dioctadecylamide) of "trehalose dicarboxylic acid", [(alpha-D-glucopyranosyluronic acid) (alpha-D-glucopyranosiduranic acid)], showed the highest serodiagnostic discriminating power (93% sensitivity and specificity). We postulate that either these artificial molecules are cross-reactants of similarly structured native glycolipids of M. tuberculosis or that they bear closer resemblance to actual phagosome-lysosome-modified antigens than to native mycobacterial ones.  相似文献   
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