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991.
BACKGROUND: Traditional mechanisms of assessing port-wine stain response to laser therapy have rested mainly on subjective determinations by physician and patient. However, the wide variation in treatment response poses a profound need for objective devices to measure treatment outcomes so that maximum effectiveness of therapy can be achieved without unnecessary repeat treatments. OBJECTIVE: The purpose of this paper will be to review noninvasive techniques to measure port-wine stain response to laser therapy. METHODS: This report is based on a review of medical and bioscience literature. RESULTS: Several techniques including laser Doppler, reflectance spectrophotometry, tristimulus colorimetry, and videomicroscopy have been developed to address the need for objective measurement devices. CONCLUSION: While many instruments are available, these techniques are limited by cost, small test size area, and/or inconclusive correlation with clinical response. A number of experimental techniques may circumvent many of the problems inherent in currently-available commercial technologies.  相似文献   
992.
PURPOSE: Type 2 diabetes mellitus (DM2) may be a risk factor in determining cancer progression. The aim of this study was to compare the progression of primary gingival cancer in patients with DM2 and nondiabetic patients. PATIENTS AND METHODS: Prospective follow-up studies involved patients with gingival squamous cell carcinoma in stage T2-3N0M0. Treatment comprised surgical tumor extirpation, block resection of the mandible, functional cervical dissection, and 60 Gy of adjuvant irradiation. The patients were divided into a group of patients with DM2 (DM group) and a nondiabetic, control group. Progression data was recorded after a 2-year period of clinical follow-up. Surgical samples were assessed histopathologically from the aspect of tumor spread. RESULTS: At the end of a 2-year follow-up period, the DM group demonstrated significantly worse clinical results in terms of cervical lymph node metastases (P<.05) and mortality rate (P<.001). Histologically, the degree of tumor invasion was significantly different in the DM group and controls (P<.01). CONCLUSION: DM2 can be considered a possible prognostic factor in cases of gingival carcinoma, forecasting an unfavorable course.  相似文献   
993.
994.
The relationship between muscle mechanical conditions and gene expression was investigated by varying both stress and contraction mode imposed upon rat dorsiflexors ( n = 25), activating them at high or low frequencies (150 Hz or 40 Hz) either eccentrically or isometrically. Muscle physiological, immunohistochemical and gene expression changes were then measured 24 h after the exercise bout. Peak stress was the best predictor of muscle injury, independent of contraction mode (i.e. eccentric or isometric). When peak stresses were matched, no physiological or immunohistochemical differences were detected between isometric and eccentric contractions. The expression of certain myogenic regulatory and muscle ankyrin repeat protein (MARP) genes ( myoD , myogenin , MLP and CARP ) depended both on peak muscle stress achieved during contraction and contraction mode. In contrast, Arpp / Ankrd2 was dramatically upregulated only by eccentric contractions, but not by isometric contractions, even though the stress level of the eccentric contractions varied over a three-fold range and overlapped with that of the isometric group. The role that Arpp/Ankrd2 upregulation plays in the biological response to eccentric contraction remains to be determined, as does the control mechanism whereby the expression of certain genes (such as myoD , myogenin, MLP and CARP ) is sensitive to muscle stress while another (Arpp/Ankrd2) is sensitive only to contraction mode.  相似文献   
995.
Isolated rat retina was preloaded with [(14)C]glutamate and subsequently superfused to follow release of glutamate (Glu). After 20 min of superfusion in the dark, exposure of the [(14)C]Glu preloaded rat retina to a single train of white light pulses reduced Glu efflux significantly in the absence as well as in the presence of low (4 microM) and high (0.5 mM) concentrations of the Glu uptake inhibitor trans-L-pyrrolidine-2,4-dicarboxylate (t-PDC). The dark-light response was the highest in the presence of 4 microM t-PDC by establishing a plateau at 75% +/- 7% of the tonic Glu release in the dark (100%). Displaying transient to saturating responses with increasing relative luminance, time series of four trains of white light pulses arrived at a plateau of 85% +/- 10%. The cyclic guanosine monophosphate (cGMP) phosphodiesterase inhibitor Zaprinast (200 microM) antagonized the effect of the light series, leading to a plateau of 115% +/- 9%. Exposure of the retina to the guanylyl cyclase inhibitor LY83583 (30 and 100 microM) showed fast, transient responses characterized by peaks at 90% +/- 1% and 80% +/- 3%, respectively.  相似文献   
996.
Objective To estimate the direct burden of malaria among children younger than 5 years in sub‐Saharan Africa (SSA) for the year 2000, as part of a wider initiative on burden estimates. Methods A systematic literature review was undertaken in June 2003. Severe malaria outcomes (cerebral malaria, severe malarial anaemia and respiratory distress) and non‐severe malaria data were abstracted separately, together with information on the characteristics of each study and its population. Population characteristics were also collated at a national level. A meta‐regression model was used to predict the incidence of malaria fevers at a national level. For severe outcomes, results were presented as median rates as data were too sparse for modelling. Results For the year 2000, an estimated 545 000 (uncertainty interval: 105 000–1 750 000) children under the age of 5 in SSA experienced an episode of severe malaria for which they were admitted to hospital. A total of 24 000 (interquartile range: 12 000–37 000) suffered from persistent neurological deficits as a result of cerebral malaria. The number of malaria fevers associated with high parasite density in under‐5s in SSA in 2000 was estimated as 115 750 000 (uncertainty interval: 91 243 000–257 957 000). Conclusion Our study predicts a lower burden than previous estimates of under‐5 malaria morbidity in SSA. As there is a lack of suitable data to enable comprehensive estimates of annual malaria incidence, we describe the information needed to improve the validity of future estimates.  相似文献   
997.
BACKGROUND: Modulation of the transduction efficiency through G-protein coupled receptors, caused by external stimulation, is essential in designing antihypertrophic treatment strategies in the dysfunctional heart. We compared protein-kinase C (PKC)-dependent regulation of positive inotropic effect via alpha1-adrenoreceptor (ADR)/Gq protein in hyperdynamic versus hypertrophied myocardium. METHODS: Inotropic (work performing isolated heart) and cellular effects of alpha1-adrenoreceptor stimulation were studied in nontransgenic (Ntg) and transgenic (Tg) mice with cardiac specific overexpression of L-type voltage-dependent calcium channels (L-type VDCC). RESULTS: Transgenic hyperdynamic and hypertrophic myocardium (due to overexpression of the L-type VDCC alpha1 subunit) were characterized by a lack of positive inotropic effect (PIE) to alpha1-ADR stimulation with phenylephrine (PE), as compared to a positive response in Ntg hearts. This was partially restored by PKC inhibition with chelerythrine and staurosporine only at the hyperdynamic stage. The inability of PKC inhibition to increase positive inotropy was associated with markedly decreased cardiac-specific caveolin-3 expression, and no changes in Galphaq, PLC-beta1, caveolin-1 and alpha1-adrenoreceptor expression. CONCLUSION: In the hyperdynamic myocardium, PKC activation may be one of the switches responsible for an impaired alpha1-adrenergic positive inotropic response. In the hypertrophied myocardium, the interruption of the transduction from Galphaq-protein coupled receptors to downstream effectors may be due to the down-regulation of caveolin-3 expression.  相似文献   
998.
BACKGROUND/AIMS: The pathogenesis of acute stress-related hemorrhage in critically ill polytraumatized patients is uncertain and any role of Helicobacter pylori infection is unknown. The aim of our study was to evaluate the relationship between Helicobacter pylori serological status of patients developing stress-related bleeding and those with no appearance of upper gastrointestinal bleeding. METHODOLOGY: In our single-center prospective cohort study we investigated over a 3-year period all consecutive patients with upper gastrointestinal hemorrhage for Helicobacter pylori infection by serology. Control group comprised 101 such patients with no evidence of hemorrhage. RESULTS: Of 396 assessable patients, stress-related upper gastrointestinal bleeding was observed in 11 (3.1%) patients. Six (55%) of the 11 bleeding patients and 45 (45%) of the 101 control group patients had serological evidence of Helicobacter pylori infection (p=0.5). Bleeding developed significantly more often in patients with more serious injury (for ISS, p=0.04, for TRISS p=0.03). Bleeding patients showed insignificantly higher mortality (36% vs. 15%; p=0.09). CONCLUSIONS: Helicobacter pylori infection was not significantly more prevalent in polytraumatized patients with hemorrhage when compared with control group. Our data suggest that the infection with Helicobacter pylori does not play an important role in bleeding, indicating no causative role for it in upper gastrointestinal hemorrhage of polytraumatized patients. The incidence of bleeding is low and bleeding develops usually later, in the meantime is the Helicobacter pylori infection eradicated with the antibiotics used for another purpose.  相似文献   
999.
OBJECTIVE: It had been suggested that programming of the hypothalamo-pituitary-adrenal axis may underlie the associations of reduced size at birth with raised blood pressure in later life. We investigated whether morning salivary cortisol mediates the inverse association of birthweight with systolic blood pressure in children. DESIGN: Subjects and measurements--a historical cohort study involving 1152 Swedish children aged 5-14 years, who took part in a family study comprised of mother, father, and two full-sibs delivered in 1987-1995 after 38-41 weeks gestation within 36 months of each other. Birthweight and gestational age were available from obstetric records. Blood pressure, weight, height and puberty stage were measured at a clinic. Cortisol was measured by radioimmunoassay in morning salivary samples taken at home, within 30 min of waking. RESULTS: Morning cortisol showed a weak negative association with length of gestation in siblings, was not related to birthweight or to systolic or diastolic blood pressure. There was no change in the strength of the negative association between birthweight and systolic blood pressure on adjustment for cortisol (-1.4 mmHg/kg, 95% CI -2.7, -0.2; adjusted for age, sex, puberty stage, weight and height, and cortisol). CONCLUSIONS: Morning cortisol was not associated with size at birth, and did not mediate the birthweight-blood pressure association in children born from full-term pregnancies. It is possible that basal cortisol levels are of more importance in explaining associations of size at birth with later blood pressure in older subjects, or in populations with more varied length of gestation. Alternatively, our results may be caused by misclassification of the hypothalamo-pituitary-adrenal activity.  相似文献   
1000.
OBJECTIVE:. To compare the clinical efficacy of custom foot orthotics, prefabricated "off-the-shelf" shoe inserts, and supportive athletic shoes worn alone, on reducing pain and improving function for children with juvenile idiopathic arthritis (JIA). METHODS: Children with JIA and foot pain (n = 40) were randomized to one of 3 groups receiving: (1) custom-made semirigid foot orthotics with shock absorbing posts (n = 15), (2) off-the-shelf flat neoprene shoe inserts (n = 12), or (3) supportive athletic shoes with a medial longitudinal arch support and shock absorbing soles worn alone (n = 13). Foot pain and functional limitations were measured using the Pediatric Pain Questionnaire-visual analog scale (VAS), Timed Walking, Foot Function Index (FFI), and the Physical Functioning Subscale of the Pediatric Quality of Life Inventory (PedsQL). Measures were administered by personnel blinded to group status at baseline (before wearing the assigned intervention) and at 3 months' followup. RESULTS: Children in the orthotics group showed significantly greater improvements in overall pain (p = 0.009), speed of ambulation (p = 0.013), activity limitations (p = 0.002), foot pain (p = 0.019), and level of disability (p = 0.024) when compared with the other 2 groups. Both children and parents in the orthotics group reported clinically meaningful improvement in child health-related quality of life, although the group by time interaction did not show statistical significance. Except for a reduction in pain for supportive athletic shoes (paired t test, p = 0.011), neither the off-the-shelf shoe inserts nor the supportive athletic shoes worn alone showed significant effect on any of the evaluation measures. CONCLUSION: In children with JIA, custom-made semirigid foot orthotics with shock-absorbing posts significantly improve pain, speed of ambulation, and self-rated activity and functional ability levels compared with prefabricated off-the-shelf shoe inserts or supportive athletic shoes worn alone.  相似文献   
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