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61.
PURPOSE: The purpose is to investigate an additional antiemetic effect to ondansetron with needle acupuncture at P6 compared with nonskin-penetrating placebo acupuncture in patients undergoing high-dose chemotherapy and autologous peripheral blood stem cell transplantation. EXPERIMENTAL DESIGN: Eighty patients who were admitted to hospital for high-dose chemotherapy and autologous peripheral blood stem cell transplantation were included into a randomized placebo-controlled single-blind trial. The patients were randomized to receive acupuncture (n = 41) or noninvasive placebo acupuncture (n = 39) at the acupuncture point P6 30 min before first application of high-dose chemotherapy and the day after. All patients received 8 mg ondansetron/day i.v. as basic antiemetic prophylaxis. The main outcome measure was the rate of patients who either had at least one episode of vomiting or required any additional antiemetic drugs on the first 2 days of chemotherapy. RESULTS: The main outcome measure showed no significant difference (P = 0.82): 61% failure in the acupuncture group and 64% in the placebo acupuncture group (95% confidence interval of 3% difference: -18.1 and 24.3%). Comparing nausea, episodes of vomiting or retching and number of additionally required antiemetic drugs did not provide any discrepancy with the main result. CONCLUSIONS: This study suggests that in combination with ondansetron i.v., invasive needle acupuncture at P6 compared with nonskin-penetrating placebo acupuncture has no additional effect for the prevention of acute nausea and vomiting in high-dose chemotherapy.  相似文献   
62.
Hydroxyethyl starch (HES) solutions are widely used to replace intravascular volume. HES solutions differ from each other with regard to molecular weight and mode of hydroxyl substitution (degree of hydroxylation, C2:C6 hydroxyethyl ratio, concentration), factors which may have varying effects on coagulation. We studied, in vitro, three different HES preparations (molecular weight/degree of hydroxylation/concentration/C2:C6 ratio of substitution 70.000/0. 5/6%/3.2; Pharmacia & Upjohn Co., Erlangen, Germany; 130.000/0. 4/6%/11.2 and 200.000/0.5/6%/4.6; Fresenius Co., Bad Homburg, Germany) and, for comparison, lactated Ringer's solution (RL) at 33% and 66% dilution with whole blood. The influence of hemodilution was measured by using routine laboratory variables and SONOCLOT (Sonoclot II Coagulation and Platelet Function Analyzer, Sienco Co.) analysis, using a viscoelastic test, on the cellular as well as on the plasmatic hemostatic system. For statistical analysis of quantitative data, we used nonparametric analysis of variance and adequate post hoc tests. Qualitative data were analyzed by using the nonparametric Kruskal-Wallis test. A P value below 0.05 was considered significant. In contrast to the control group with RL, the liquid phase of coagulation (activated clotting time) was slightly affected by the 33% diluted HES solutions. HES 70.000, 130. 000, and 200.000 interfered significantly with the early stage of coagulation as expressed by the clot rate (gel/fibrin formation). Clot maturation and speed of maturation (time to peak) were strongly affected by HES 70.000 at all grades of dilution. HES 130.000 showed a faster clot formation process compared with the other HES solutions. HES 130.000 diluted 33% showed a better clot retraction as compared with the other HES solutions. In conclusion, in vitro hemodilution comparing different medium molecular weight HES solutions reveals that HES 130.000 seems preferable regarding some aspects of clot formation and retraction. RL affected clot formation only minimally, except for the early activation of clotting, which was measured by a shortened activated clotting time. IMPLICATIONS: We investigated the effect of different hydroxyethyl starch (HES) solutions (70.000, 130.000, 200.000) on coagulation. Regarding clot formation and retraction, HES 130.000 had some advantages over the other tested HES solutions. Lactated Ringer's solution affected coagulation only minimally, except for the early stage of clot formation.  相似文献   
63.
A comparison of autorefractor performance.   总被引:1,自引:0,他引:1  
PURPOSE: To compare the agreement between subjective refraction and autorefraction using two commercially available autorefractors. METHODS: Prospective data were collected for 190 subjects using either the Nidek ARK-700A (Fremont, CA) or the Topcon KR-8000 (Paramus, NJ) and subjective refraction (masked to autorefraction). Refractions were compared in terms of spherical equivalent using Bland-Altman limits of agreement and astigmatic vector difference using median and 95th percentile. RESULTS: The two groups were similar for age, gender, spherical equivalent, and astigmatic power. The differences in spherical equivalent between subjective and autorefraction were significantly different (mean +/- SD; Nidek, -0.03 +/- 0.36 D; Topcon, +0.11 +/- 0.34 D; analysis of variance, F = 7.84; p < 0.01). However, the 95% limits of agreement were similar: Nidek, -0.74 to +0.68 D; Topcon, -0.55 to +0.77 D. The median differences in astigmatic vector difference were also similar: Nidek, 0.27 D and Topcon, 0.25 D. However, the 95th percentile was 0.67 D for Nidek and 1.09 D for Topcon. There was a low frequency of large (>1.00 D) differences in spherical equivalent, 1.1% with each autorefractor. There were five cases with astigmatic vector difference >1 D, all with the Topcon KR-8000 (5.3%). CONCLUSIONS: Both autorefractors show excellent agreement with subjective refraction. Despite a statistically significant difference in mean spherical equivalent (0.14 D), near identical limits of agreement (0.10 D difference) suggest clinical equivalence. Conversely, for astigmatism, despite similar median scores, major outliers were more likely with the Topcon, reflected in a 0.42 D larger 95th percentile, which suggests a small advantage for the Nidek for avoiding large astigmatic errors.  相似文献   
64.
65.
In typical development, empathic abilities continue to refine during adolescence and early adulthood. Children and adolescents with autism spectrum disorders (ASD) show deficits in empathy, whereas adults with ASD may have developed compensatory strategies. We aimed at comparing developmental trajectories in the neural mechanisms underlying empathy in individuals with ASD and typically developing control (TDC) subjects. Using an explicit empathizing paradigm and functional magnetic resonance imaging, 27 participants with ASD and 27 TDC aged 12–31 years were investigated. Participants were asked to empathize with emotional faces and to either infer the face’s emotional state (other-task) or to judge their own emotional response (self-task). Differential age-dependent changes were evident during the self-task in the right dorsolateral prefrontal cortex, right medial prefrontal cortex, right inferior parietal cortex, right anterior insula and occipital cortex. Age-dependent decreases in neural activation in TDC were paralleled by either increasing or unchanged age-dependent activation in ASD. These data suggest ASD-associated deviations in the developmental trajectories of self-related processing during empathizing. In TDC, age-dependent modulations of brain areas may reflect the ‘fine-tuning’ of cortical networks by reduction of task-unspecific brain activity. Increased age-related activation in individuals with ASD may indicate the development of compensatory mechanisms.  相似文献   
66.
Phenylketonuria (PKU) is an autosomal recessive metabolic disease caused by an error of phenylalanine metabolism. Delayed treatment or treatment performed unsystematically might lead to neurological disorders and progressive intellectual disability. In the Prader-Willi syndrome (PWS) clinical manifestations change with age. Feeding difficulties resulting from the poor suck and hypotonia are typical in the neonatal period and early infancy. As patients grow their activities increase, muscle tone improves, the extreme hyperphagia appears – the main cause of obesity. Mental development of patients is usually mildly retarded. We report the case of a patient affected by two genetic diseases: PKU and PWS. Variety of clinical symptoms and abnormal results of laboratory analyses make the correct diagnosis difficult. Elevated phenylalanine level in screening newborn test, disorders of muscle tone, poor suck, and low urine biopterin concentration did not allow to clearly rule out the hyperphenylalaninemia caused by a tetrahydrobiopterin deficiency (BH4). Data from obstetric anamnesis and the early postnatal clinical findings suggested the PWS. Hyperphagia and the increased risk of carbohydrates tolerance disorders in patients with PWS make it very difficult to balance properly the low-phenylanine diet necessary in PKU treatment. The patient presented by us needs well-coordinated multidisciplinary medical care which aims to provide proper physical development and to support the boy's mental potential as well as appropriate functioning in the society.  相似文献   
67.
68.
A capability for effective tissue reparation is a living requirement for all multicellular organisms. Bone exits as a precisely orchestrated balance of bioactivities of bone forming osteoblasts and bone resorbing osteoclasts. The main feature of osteoblasts is their capability to produce massive extracellular matrix enriched with calcium phosphate minerals. Hydroxyapatite and its composites represent the most common form of bone mineral providing mechanical strength and significant osteoinductive properties. Herein, hydroxyapatite and fluorapatite functionalized composite scaffolds based on electrospun polycaprolactone have been successfully fabricated. Physicochemical properties, biocompatibility and osteoinductivity of generated matrices have been validated. Both the hydroxyapatite and fluorapatite containing polycaprolactone composite scaffolds demonstrated good biocompatibility towards mesenchymal stem cells. Moreover, the presence of both hydroxyapatite and fluorapatite nanoparticles increased scaffolds’ wettability. Furthermore, incorporation of fluorapatite nanoparticles enhanced the ability of the composite scaffolds to interact and support the mesenchymal stem cells attachment to their surfaces as compared to hydroxyapatite enriched composite scaffolds. The study of osteoinductive properties showed the capacity of fluorapatite and hydroxyapatite containing composite scaffolds to potentiate the stimulation of early stages of mesenchymal stem cells’ osteoblast differentiation. Therefore, polycaprolactone based composite scaffolds functionalized with fluorapatite nanoparticles generates a promising platform for future bone tissue engineering applications.  相似文献   
69.
Microtexturing of implant surfaces is of major relevance in the endeavor to improve biorelevant implant designs. In order to elucidate the role of biomaterial’s topography on cell physiology, obtaining quantitative correlations between cellular behavior and distinct microarchitectural properties is in great demand. Until now, the microscopically observed reorganization of the cytoskeleton on structured biomaterials has been difficult to convert into data. We used geometrically microtextured silicon-titanium arrays as a model system. Samples were prepared by deep reactive-ion etching of silicon wafers, resulting in rectangular grooves (width and height: 2 µm) and cubic pillars (pillar dimensions: 2 × 2 × 5 and 5 × 5 × 5 µm); finally sputter-coated with 100 nm titanium. We focused on the morphometric analysis of MG-63 osteoblasts, including a quantification of the actin cytoskeleton. By means of our novel software FilaQuant, especially developed for automatic actin filament recognition, we were first able to quantify the alterations of the actin network dependent on the microtexture of a material surface. The cells’ actin fibers were significantly reduced in length on the pillared surfaces versus the grooved array (4–5 fold) and completely reorganized on the micropillars, but without altering the orientation of cells. Our morpho-functional approach opens new possibilities for the data correlation of cell-material interactions.  相似文献   
70.
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