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According to the commonest definition, infant colic is distinguished by crying which is 'paroxysmal'-that is, intense and different in type from normal fussing and crying. To test this, maternal reports of the distress type of 67 infants whose fuss/crying usually exceeded three hours a day ('persistent criers') were scrutinised using 24 hour audiorecordings of the infants' distressed vocalisation. 'Moderate criers' (n = 55) and 'evening criers' (n = 38) were also assessed. Most of the distress in all three groups was fussing. In the audiorecordings the persistent criers showed a higher crying: fussing ratio than the moderate criers, but intense crying was rare. A third of the persistent criers were reported by their mothers to have occasional, distinct colic bouts of 'intense, unsoothable crying and other behaviour, perhaps due to stomach or bowel pain.' In the audiorecordings these periods were longer, but not paroxysmal in onset or more intense than the crying of persistent criers not judged to have colic. The audible features of the crying may be less important than its unpredictable, prolonged, hard to soothe, and unexplained nature.  相似文献   
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The bird's nest inferior vena cava filter: progress report   总被引:7,自引:0,他引:7  
Roehm  JO  Jr; Johnsrude  IS; Barth  MH; Gianturco  C 《Radiology》1988,168(3):745-749
The bird's nest inferior vena cava filter, in clinical trial since 1982, has been placed in 568 patients at risk for pulmonary embolism. Of the 481 patients in whom the filter had been in place for 6 months or more, 440 were followed up clinically. The prevalence of clinically suspected recurrent pulmonary thromboembolism was 2.7% (12 patients) and that of inferior vena cava filter occlusion was 2.9% (13 patients). With the initial filter design, filter migration occurred in five patients. No migrations have occurred in the 147 patients treated with the filter after its modification to improve the anchoring system for greater stability. The bird's nest filter has proved safe and effective in the prevention of pulmonary embolism.  相似文献   
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经大鼠门静脉注射乳胶微球,以完全阻塞肝内的门静脉分支,并观察门静脉压力(PVP)的变化。结果表明,门静脉内注射直径为15或80μm的微球使PVP分别增加了102.2%和272.3%;顺序注射不同组合的微球(15μm+40μm+80μm或80μm+40μm+15μm)并未使PVP获得进一步的升高(分别增加了162.8%和178.6%)。尽管门静脉内注射乳胶微球可使PVP显著升高,但却无法达到肝外门静脉钳闭时的高度(4.87~5.75kPa)。肝静脉楔入压(WHVP)于门静脉钳闭时明显下降,但在注射15μm的微球后却与PVP同步升高。所有实验鼠肺内均发现有许多微球。上述结果提示正常大鼠可能存在肝内门-体分流。  相似文献   
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Sensitivity and specificity of first screen mammography in a randomized screening trial at five centers are reported. A total of 23,101 women underwent mammography; in 139, breast cancer was detected at first screening; in 20, less than 12 months after first screening; and in 47, at second screening. All 206 cancer cases were histologically confirmed, and 174 were defined as being detectable at first screening. Average length of follow-up for all women was 3.2 years. Interpretations of first screen mammograms by the center radiologists were matched to known outcomes. Simultaneous blind review was performed by a single reference radiologist with mammograms from all 206 cancer cases and those of a random sample of 739 women not known to have breast cancer at 15 months or more after initial screening. Overall, the five screening centers achieved a sensitivity of 69% (range, 60%-78%), a specificity of 94% (range, 93%-96%), a positive predictive value of 8.6% (range, 3%-16%), and a negative predictive value of 99.7% (range, 99.6%-99.9%).  相似文献   
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We have previously demonstrated Clara cell protein (CC16) [secretoglobin 1A1] in serum to be a highly sensitive biomarker of altered lung epithelial permeability after ozone challenge. As a previous experimental study has indicated a diurnal variation in serum CC16 in humans, the aims of the present investigation were to confirm this observation and to attempt to model the diurnal variation in CC16 concentrations. In 18 healthy nonsmoking subjects, peripheral blood samples were drawn at six sampling points over a 15-h period and repeated twice within 3 to 4 weeks. A clear within-day variation was revealed in serum CC16 concentrations, falling significantly from baseline levels between the 11:30 am and 10:00 pm time points (p = 0.000). Furthermore, it was shown that this within-day variation was reproducible regardless of subject or day, enabling the diurnal variation in serum CC16 to be modeled and fitted a second-degree polynomial for the observed time span. In conclusion, the present data demonstrate a pronounced time-dependent diurnal variation in serum levels of CC16, which can be mathematically compensated for, when addressing the issue of an air pollution-induced effect on CC16 in field studies.  相似文献   
60.
Human exposure to airborne particulate matter (PM) is associated with adverse cardiopulmonary health effects, including lung cancer. Ambient PM represents a heterogeneous mixture of chemical classes including transition metals, polycyclic aromatic hydrocarbons (PAHs) and their derivatives such as nitro‐PAHs, many of which are classified as putative carcinogens. As the primary site of human exposure to PM is the lungs, we investigated the response of two alveolar epithelial cell lines, the tumour‐derived A549 and newly described TT1 cells, to fine and coarse PM collected from background and roadside locations. We show that coarse PM elicits a genotoxic response in the TT1 cells, with the strongest signal associated with the background sample. This response could be recapitulated using the organic extract derived from this sample. No responses were observed in PM‐challenged A549 cells. Fine PM failed to elicit a genotoxic response in either cell line despite the higher PAH concentrations within this fraction. Consistent with the lack of a simplistic association between PM PAH content and the observed genotoxic response, TT1 cells treated with benzo[a]pyrene (BaP) demonstrated no increase in the selected markers. In contrast, a pattern of response was observed in TT1 cells challenged with 3‐nitrobenzanthrone (3‐NBA) similar to that with coarse PM. Together, these data illustrated the suitability of the TT1 cell line for assessing PM‐induced genotoxicity and challenge the contention that fine roadside PM poses the higher cancer risk. Furthermore, the response to 3‐NBA and not BaP suggests a major contribution of nitro‐PAHs to the overall toxicity of PM. Environ. Mol. Mutagen. 59:290–301, 2018. © 2018 The Authors Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society  相似文献   
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