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1.
Cerebral blood flow tomography, by xenon 133 inhalation or HMPAO (99mTc-d, l-hexamethyl-propylene amine oxime) technetium Tc 99m injection, revealed a severe hypoperfusion in both frontal lobes of a 40-year-old woman with confirmed neuroacanthocytosis. This finding occurred in conjunction with neuropsychological deficits consistent with selective frontal lobe dysfunction. This observation is the first documentation of this type of dementia in neuroacanthocytosis.  相似文献   
2.
Tracheoesophageal voice prostheses need to be replaced due to increased airflow resistance or retrograde leakage of fluid into the trachea as a consequence of biofilm formation. Previous in vitro studies show a change of aerodynamic features of biofilm covered voice prostheses after removal of the prostheses out of the patient. To assess these changes in an in situ situation, aerodynamic characteristics were measured within 45 patients at the beginning and at the end of the wearing process of the Provox 2 voice prosthesis. As a consequence, the influence of biofilm formation on aerodynamic characteristics can be evaluated. In the majority of cases, leakage through the prosthesis was the reason for replacement. No differences were found in the total flow, volume range and intratracheal pressure (ITP) of the voice prostheses measured. The airflow resistance of biofilm covered prostheses was significantly reduced compared to new clean prostheses. However, no correlation was found between the extent of biofilm and the different aerodynamic features measured. Biofilm formation on the Provox 2 is responsible for both reduction in airflow resistance and leakage through the prosthesis by deterioration of the silicone rubber material.  相似文献   
3.
Abstract

This work presents a prospective morphological and quantitative analysis of 43 intracranial pressure recordings performed on normal pressure hydrocephalic patients. This analysis led us to separate Lundberg's B waves into different subtypes and to refine the definition of the ‘Plateau’ wave. Two B wave subtypes named Great Symmetrical wave and Intermediate wave appeared correlated with the surgical improvement. In additioni, the degree of post-operative improvement was correlated with the frequency of Intermediate wave. An extended quantitative classification of intracranial pressure waves is proposed that can be used alone to determine which patients should undergo a shunting procedure and which one should the most improve.  相似文献   
4.
OBJECTIVE: Epstein-Barr virus (EBV)-based vectors have favorable features for gene transfer, including a high transduction efficiency especially for B cells, large packaging capacity up to 150 kb pairs, and ability to infect postmitotic cells. Recombinant EBV was explored for transduction of primary human B-cell chronic lymphocytic leukemia (CLL) cells. MATERIAL AND METHODS: EBV vectors deleted for all oncogenic sequences and encoding terminal repeats (TR) essential for encapsidation, the lytic origin of replication (oriLyt) for DNA amplification, and the enhanced green fluorescent protein (EGFP) were packaged using an optimized, helper-virus-free method. Infectious EBV virions encoding EGFP (EBV/EGFP) with an infectious titer up to 2 x 10(6) per milliliter were generated. Primary leukemic cells from 14 patients with CLL were successfully transduced with EBV/EGFP at a very low multiplicity of infection (< 1). RESULTS: Transgene expression was detected in up to 85% of cells 48 hours after infection. Transduction was specifically mediated by EBV vectors because gene transfer was inhibited by an antibody (72A1) directed against the viral envelope glycoprotein gp350/220. Furthermore, transduction of CLL cells with packaged EBV vectors coding for EGFP but deleted for TR sequences (TR-) did not result in EGFP expression compared to TR+ vector constructs (p = 0.009). CONCLUSION: Helper-virus-free EBV-based gene transfer vectors hold promise for development of genetic therapies for CLL patients.  相似文献   
5.
Leg-extensor rate of power development (RPD) decreases during aging. This study aimed to identify the underlying mechanism of the age-related decline in RPD during a fast acceleration in terms of in vivo vastus lateralis (VL) fascicle shortening behavior. Thirty-nine men aged between 25 and 69 years performed three maximal isokinetic leg-extensor tests with a fixed initial acceleration of 45° knee extension in 150 ms until 340°/s knee angular velocity. RPD, VL activity, and ultrasound images were recorded to assess (relative) fascicle shortening and mean shortening velocity for the phases of electromechanical delay, pretension, and acceleration. Our findings show that fascicle shortening and mean shortening velocity during a fast action increase with aging (0.002 per year, P = .035 and 0.005 s−1 per year, P = .097, respectively), mainly due to a higher amount of shortening in the phase of electromechanical delay. The ratio of VL fascicle length over upper leg length at rest showed a negative correlation (r = −.46, P = .004) with RPD/body mass, while pennation angle at rest showed a trend toward a positive correlation (r = .28, P = .089). To conclude, our findings indicate that the ability to reach high VL fascicle shortening velocities in vivo is not reduced in older men while performing preprogrammed fast accelerations. The greater amount of fascicle shortening in old age is probably the result of age-related differences in the tendinous properties of the muscle-tendon complex, forcing the fascicles to shorten more in order to transmit the muscle force to the segment.  相似文献   
6.
7.
The aim of this study was to investigate and to compare the effect of 24 weeks "whole body vibration" training and fitness training on body composition and on muscle strength. Forty-eight untrained females (21.3 +/- 2.0 yr) participated in the study. The whole body vibration group (N = 18) performed unloaded static and dynamic exercises on a vibration platform (35 - 40 Hz, 2.5 - 5.0 mm; Power Plate). The fitness group (N = 18) followed a standard cardiovascular (15 - 40 min) and resistance training program including dynamic leg press and leg extension exercises (20 - 8 RM). Both groups trained 3 times weekly. The control group (N = 12) did not participate in any training. Body composition was determined by means of underwater weighing. Additionally 12 skinfolds were assessed. Isometric (0 degrees /s) and isokinetic (50 degrees /s, 100 degrees /s, 150 degrees /s) knee-extensor strength was measured by means of a motor-driven dynamometer (Technogym). Over 24 weeks there were no significant changes (p > 0.05) in weight, in percentage body fat, nor in skinfold thickness in any of the groups. Fat free mass increased significantly in the whole body vibration group (+ 2.2 %) only. A significant strength gain was recorded in the whole body vibration group (24.4 +/- 5.1 %; 5.9 +/- 2.1 %; 8.3 +/- 4.4 %; 7.6 +/- 1.5 %) and in the fitness group (16.5 +/- 1.7 %; 12.0 +/- 2.7 %; 10.4 +/- 2.3 %; 10.2 +/- 1.9 %), at 0 degrees /s, 50 degrees /s, 100 degrees /s and 150 degrees /s respectively. In conclusion, 24 weeks whole body vibration training did not reduce weight, total body fat or subcutaneous fat in previously untrained females. However, whole body vibration training induces a gain in knee-extensor strength combined with a small increase in fat free mass. The gain in strength is comparable to the strength increase following a standard fitness training program consisting of cardiovascular and resistance training.  相似文献   
8.
BACKGROUND: The efficacy and safety of sublingual immunotherapy (SLIT) in patients with chronic rhinitis related to sensitization to house dust mites are still controversial. METHODS: After application of an anti-mite mattress cover, patients were only included in the study when the cumulative symptom score over a fortnight was greater than 70 out of a possible total of 168. Thirty-two of the 120 patients selected were randomized to receive SLIT for 2 years: 17 received placebo and 15 received the Dermatophagoides pteronyssinus and D. farinae 50/50 allergen extract. RESULTS: Significant between-group differences were observed after 1 year and persisted at the end of the second year for the rhinitis total score (P < 0.02), blocked nose score (P < 0.01) and nasal itching score (P < 0.01). Skin reactivity to house dust mites was significantly reduced in the group receiving house dust mite extract (P < 0.03). No statistical difference was observed between the two groups for medication scores, but a low medication consumption was observed in all patients. No serious and no systemic adverse reactions were reported. CONCLUSION: This study indicates the superiority of active treatment vs. placebo, evaluated on efficacy criteria (rhinitis score) or objective criteria (skin reactivity). The availability of a solid form (tablet) could represent a progress in terms of patient acceptability.  相似文献   
9.
BACKGROUND: Although health-related benefits of fitness training in older men are well established, it is not clear yet which mode and intensity of a exercise program is most effective. This study addresses whether the combination of endurance (ED) and resistance training in older men have supplementary health-related benefits in addition to profits attained through endurance training alone. Additionally, effects of moderate- and low-intensity resistance training are compared. METHODS: Men, 55-75 years of age, were randomly assigned to a control group (N = 13) or one of three exercise groups (20 weeks, two to three times per week): endurance plus moderate resistance (MR) training (N = 22), endurance plus low resistance (LR) training (N = 22) and endurance training only (N = 22). Cardiovascular (CV) risk factors, muscular fitness and postural control were assessed before and after training. RESULTS: All exercise groups revealed significant (P < 0.05) improvements in resting heart rate, work capacity and recovery, waist girth, insulin response and knee-extensor strength with no differences among groups. Body composition, resting metabolic rate (RMR), VO2peak and postural control did not change in exercise groups. CONCLUSION: In older men, a fitness program consisting of 20 weeks endurance training combined with resistance training is equally effective as endurance training alone. Moderate vs. low resistance training added to endurance training yields similar health-related benefits.  相似文献   
10.
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