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1.
This study investigated the effects of high-intensity ultrasound and glycosylation on the structural and interfacial properties of the Maillard reaction conjugates of buckwheat protein isolate (BPI). The covalent attachment of dextran to BPI was confirmed by examination of the Fourier-transform infrared spectra. Emulsifying properties of the conjugates obtained by ultrasound treatment were improved as compared to those obtained by classical heating. Structural feature analyses suggested that conjugates obtained by ultrasound treatment had less α-helix and more random coil, higher surface hydrophobicity and less compact tertiary structure as compared to those obtained by classical heating. The surface activity measurement revealed that the BPI–dextran conjugates obtained by ultrasound treatment were closely packed and that each molecule occupied a small area of the interface. Combination of ultrasonic treatment and glycosylation was proved to be an efficient way to develop new stabilizers and thickening agents for food in this study.  相似文献   
2.
The value of thyroid scintigraphy in hyperthyroidism diagnosis has long been the subject of debate. Unresolved issue is whether scintigraphy should be performed routinely, selectively, or for all hyperthyroidism patients. So, this study is concerned with the evaluation of thyroid scintigraphy for identifying hyperthyroidism in comparison with thyroid stimulating hormone (TSH) and ultrasound. This is cross sectional study including convenient patients sample (n = 50, 15 males and 35 females) aged (20–50 years) with primary hyperthyroidism and were attending endocrine clinics at King Faisal Specialist Hospital and Research Centre. All patients performed clinical investigations (TSH, ultrasound and thyroid scintigraphy). Among these patients, 96%, 48/50, had positive findings for hyperthyroidism with thyroid SC (95% CI; 96.0–99.5%); 84%, 42/50, had positive findings for hyperthyroidism by US (95% CI; 70.9–92.8%); and 56%, 28/50, had positive findings for hyperthyroidism by TSH measurement (95% CI; 41.3.0–70.0%). There was very good agreement between scintigraphy diagnosis and ultrasonography (kappa score = 0.812 (P < 0.0001), 95% CI (0.77–0.85). In many cases, scintigraphy provides considerably more functioning and anatomic details than ultrasound. In conclusion, these findings bring forth practical aspects of thyroid scintigraphy utilization for hyperthyroidism. By combining functional and anatomical information in one step, scintigraphy provides non-invasive, simple, fast and cost effective hyperthyroidism diagnostic method and has the potential to replace TSH and ultrasonography in hyperthyroidism investigation.  相似文献   
3.
Unilateral cerebral palsy (uCP) causes upper limb movement disorders that impact on daily activities, especially in bimanual condition. However, a few studies have proposed bimanual tasks for 3D motion analysis. The aim of this study was to validate the new version of a child-friendly, 3D, bimanual protocol for the measurement of joint angles and movement quality variables. Twenty children with uCP and 20 typically developing children (TDC) performed the five-task protocol integrated into a game scenario. Each task specifically targeted one or two upper limb degrees of freedom. Joint angles, smoothness and trajectory straightness were calculated. Elbow extension, supination, wrist extension and adduction amplitudes were reduced; hand trajectories were less smooth and straight in children with uCP compared to TDC. Correlations between the performance-based score and kinematic variables were strong. High within and between-session reliability was found for most joint angle variables and lower reliability was found for smoothness and straightness in most tasks. The results therefore demonstrated the validity and reliability of the new protocol for the objective assessment of bimanual function in children with uCP. The evaluation of both joint angles and movement quality variables should increase understanding of pathological movement patterns and help clinicians to optimize treatment.ClinicalTrials.gov identifier: NCT03888443.  相似文献   
4.
Ultrasound imaging (USI) of muscle thickness offers different insights into musculoskeletal function than kinematics, kinetics, and surface electromyography (sEMG), however it is unknown how USI-derived measures correlate to traditional measures during walking. The purpose of this study was to compare USI-derived gluteus maximus (GMAX) and medius (GMED) thickness measures to tri-planar hip kinematics and kinetics, and GMED thickness to sEMG amplitude. Fourteen females walked on a treadmill at 1.34 m/s. GMAX and GMED thickness, hip tri-planar kinematics, kinetics, and GMED sEMG were simultaneously recorded. USI-derived thickness measures were compared to other biomechanical outcomes using cross-correlation analyses, computed at each 1% (11-ms) of the gait cycle with lag times from −20% to 20%. GMED and GMAX thickness measures were most strongly correlated with hip extension and abduction angles at 150–220-ms lags (cross-correlation coefficients [CCF]: −0.34; −0.83). GMED thickness was most correlated to abduction and external rotation moments simultaneously (CCF: −0.28; −0.47). GMAX thickness and flexion moments were most strongly correlated at a 66-ms lag (CCF: 0.33). GMED sEMG amplitude was most strongly correlated to muscle thickness at a 99-ms lag (CCF: 0.39). These results elucidate the unique information provided from USI-derived measures of gluteal muscle thickness during walking.  相似文献   
5.
6.
Reproductive failure in two female gorillas in the Los Angeles Zoo led to evaluation for secondary infertility. Male factor was excluded by noting routine conceptions in other individuals in the same group, and by behavioral observations of coital activity with the infertile females. Biochemical evidence of ovarian function was obtained by urinary sex steroid analysis. Continuity of the reproductive tract of the infertile apes was then studied by hysterosalpingography and laparoscopy while their general health was evaluated by ultrasonography and physical examination. Progressive, multiorgan involvement with Echinococcus vogeli was documented and mebendazole therapy begun. The investigation of secondary infertility in great apes by combined methods is safe and accurate, but requires special equipment and experienced personnel.  相似文献   
7.
Pallister-Killian syndrome (PKS) is a rare sporadic genetic disorder usually caused by mosaicism of an extra isochromosome of 12p (i(12p)). This retrospective study analysed the prenatal ultrasound manifestations and molecular and cytogenetic results of five PKS foetuses. Samples of amniotic fluid and/or cord blood, skin biopsy and placenta were collected. Conventional karyotyping and single nucleotide polymorphism array (SNP array) were performed on all the amniotic fluid or cord blood samples. Copy number variants sequencing (CNV-seq) and fluorescence in situ hybridization (FISH) were also used for the validation for one foetus. All the five foetuses were from pregnancies with advanced parental age. Two foetuses involved structural abnormalities and one foetus had only soft markers, all of which included increased nuchal translucency. The rest two foetuses had normal ultrasounds in the second trimester, which has rarely been reported before. The karyotype revealed typical i(12p) in four cases and a small supernumerary marker chromosome consisting of 12p and 20p in the remaining one case. The proportion of cells with i(12p) ranged from 0 to 100% in cultural cells, while SNP array results suggested 2−4 copies of 12p. For one foetus, metaphase FISH showed normal results, but the interphase FISH suggested cell lines with two, three and four copies of 12p in the amniotic fluid. Advanced parental age may be an important risk factor for PKS, and there were no typical ultrasound manifestations related to PKS. A combination of karyotype analysis and molecular diagnosis is an effective method for the diagnosis of PKS.  相似文献   
8.
Compelling evidence suggests the limitation and shortcomings of the current and well established cell culture method using multi-well plates, flasks and Petri dishes. These are particularly important when cell functions are sensitive to the local microenvironment, cell–cell and cell–extracellular matrix interactions. There is a clear need for advanced cell culture systems which mimic in vivo and more physiological conditions. This review summarises and analyses recent progress in three dimensional (3D) cell culture with perfusion as the next generation cell culture tools, while excluding engineered tissue culture where three dimensional scaffold has to be used for structural support and perfusion for overcoming mass transfer control. Apart from research activities in academic community, product development in industry is also included in this review.  相似文献   
9.
Well-ordered three-dimensional crystals of 70 S ribosomes and 30 S ribosomal subunits from extremely thermophilic bacteria Thermus thermophilus have been obtained. Positively stained thin sections of the crystals have been analyzed by electron microscopy. Redissolved crystalline ribosomes and small ribosomal subunits reveal sedimentation constants of 70 S and 30 S, respectively, and are functionally active in the poly(U)-system.  相似文献   
10.
Background3D freehand ultrasound enables the creation of volumetric data. The acquisition of morphological features, such as muscle volume, is influenced by the variations in force applied to the skin with the ultrasound probe. To minimise the deformations, a concave-shaped plastic mount combined with a custom-shaped gel pad was developed for the ultrasound head, named Portico. This study analyses to what extent the Portico reduces muscle deformation and corresponding errors in estimating muscle volume.MethodTwenty medial gastrocnemius (MG) muscles were assessed (10 from typically developing children; 10 from children with spastic cerebral palsy). Two repetitions were acquired in each of the following approaches: (1) with the lower leg submerged in a water tank as a non-deformed reference; (2) probe-on-skin (PoS) as the conventional approach and (3) the newly introduced Portico. PoS and Portico data were registered with respect to the ones corresponding in a water tank. An in-house software package (Py3DFreeHandUS) was used to process the data and MG volume was estimated using MeVisLab. The minimal detectable change (MDC) was calculated.ResultsWith respect to the PoS approach, the Portico reduced muscle deformation by 46%. For both the typically developing and spastic cerebral palsy cohorts, lower MDCs were found when using the Portico.DiscussionDespite the improvements, the Portico did not yield statistically more reliable MG volume estimations than the traditional PoS approach. Further improvement can be attained by optimising the fit between the gel pad and the curvature of the limb, using a larger choice of Portico geometries.  相似文献   
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