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31.
The natural history of lung hyperinflation in patients with airway obstruction is unknown. In particular, little information exists about the extent of air trapping and its reversibility to bronchodilator therapy in those with mild airway obstruction. We completed a retrospective analysis of data from individuals with airway obstruction who attended our pulmonary function laboratory and had plethysmographic lung volume measurements pre- and post-bronchodilator (salbutamol). COPD was likely the predominant diagnosis but patients with asthma may have been included. We studied 2,265 subjects (61% male), age 65 ± 9 years (mean ± SD) with a post-bronchodilator FEV(1)/FVC <0.70. We examined relationships between indices of airway obstruction and lung hyperinflation, and measured responses to bronchodilation across subgroups stratified by GOLD criteria. In GOLD stage I, vital capacity (VC) and inspiratory capacity (IC) were in the normal range; pre-bronchodilator residual volume (RV), functional residual capacity (FRC) and specific airway resistance were increased to 135%, 119% and 250% of predicted, respectively. For the group as a whole, RV and FRC increased exponentially as FEV(1) decreased, while VC and IC decreased linearly. Regardless of baseline FEV(1), the most consistent improvement following bronchodilation was RV reduction, in terms of magnitude and responder rate. In conclusion, increases (above normal) in airway resistance and plethysmographic lung volumes were found in those with only minor airway obstruction. Indices of lung hyperinflation increased exponentially as airway obstruction worsened. Those with the greatest resting lung hyperinflation showed the largest bronchodilator-induced volume deflation effects. Reduced air trapping was the predominant response to acute bronchodilation across severity subgroups. 相似文献
32.
The 4S polycyclic aromatic hydrocarbon (PAH)-binding protein (PBP) is a cytoplasmic protein that binds PAHs with specificity and high affinity. We have used antisera for the PBP and unlabeled peroxidase anti-peroxidase immunohistochemistry to demonstrate its possible localization in cell types known to have xenobiotic metabolizing capabilities. Cellular sites of the PBP in liver, lung and kidney of C57BL/6 and DBA/2 mice were probed. The PBP was visualized in hepatocytes throughout the liver lobule and was not preferentially located in either centrilobular or periportal areas. However, cellular heterogeneity with respect to PBP content was clearly evident in the hepatocyte population. The positive reactivity correlated with substantial levels of benzo[a]pyrene (B[a]P) binding in liver cytosol. In the lung, the PBP was found in the bronchiolar epithelium and the alveolar septa, and was localized in ciliated and non-ciliated Clara and alveolar type II cells as well as in alveolar macrophages. In the kidney, the glomeruli and epithelia of proximal and distal convoluted tubules and collecting ducts were labeled. Staining for the PBP was greatest in the apical region of the pyramid and was localized in the epithelial lining of the collecting ducts. Relatively lower levels of the PBP were detected in the lung and kidney than in the liver. Staining was localized in the cytoplasmic compartment of cells in all tissues examined. Similar immunoreactivities were exhibited in the tissues of both C57BL/6 and DBA/2 mice. Treatment with beta-naphthoflavone (beta NF) altered neither the intensity nor pattern of immunostaining. Furthermore, treatment with beta NF or isosafrole has no effect on the Kd and Bmax of B[a]P binding to liver cytosolic PBP. The results of our experiments demonstrate localization of the PBP to sites of active physiological response to PAH exposure. 相似文献
33.
We examined the effects of trichloroethylene (TCE) on the bronchiolar epithelium of mouse lung, using scanning electron microscopy. The lesion elicited by TCE involved predominantly the nonciliated Clara cells of the bronchiolar epithelium. Although there was slight loss of cilia and the mucosal surface exhibited increased deposits of debris throughout the period the tissues were observed, the ciliated cells appeared relatively uninjured. At 24 h following the intraperitoneal administration of TCE (2000 mg/kg) the Clara cells of the bronchiolar epithelium were irregularly distributed on the mucosal surface and reduced in number, indicating loss of cells by exfoliation. The remaining Clara cells appeared deformed and collapsed. This cell population was markedly reduced by seven days after TCE exposure, and the bulging apices characteristic of this cell type were virtually absent, resulting in a flattened epithelial lining. By 15 and 30 days after TCE, reparative processes were evident and micronodules consisting of multiple Clara cells protruded into the airway lumen. The administration of TCE to mice causes severe morphological damage to Clara cells of the bronchiolar epithelium which persists for at least 60 days after chemical exposure. 相似文献
34.
M. Groth N. D. Forkert J. H. Buhk M. Schoenfeld E. Goebell J. Fiehler 《Neuroradiology》2013,55(2):171-178
Introduction
To compare intra- and inter-observer reliability of aneurysm measurements obtained by a 3D computer-aided technique with standard manual aneurysm measurements in different imaging modalities.Methods
A total of 21 patients with 29 cerebral aneurysms were studied. All patients underwent digital subtraction angiography (DSA), contrast-enhanced (CE-MRA) and time-of-flight magnetic resonance angiography (TOF-MRA). Aneurysm neck and depth diameters were manually measured by two observers in each modality. Additionally, semi-automatic computer-aided diameter measurements were performed using 3D vessel surface models derived from CE- (CE-com) and TOF-MRA (TOF-com) datasets. Bland–Altman analysis (BA) and intra-class correlation coefficient (ICC) were used to evaluate intra- and inter-observer agreement.Results
BA revealed the narrowest relative limits of intra- and inter-observer agreement for aneurysm neck and depth diameters obtained by TOF-com (ranging between ±5.3 % and ±28.3 %) and CE-com (ranging between ±23.3 % and ±38.1 %). Direct measurements in DSA, TOF-MRA and CE-MRA showed considerably wider limits of agreement. The highest ICCs were observed for TOF-com and CE-com (ICC values, 0.92 or higher for intra- as well as inter-observer reliability).Conclusion
Computer-aided aneurysm measurement in 3D offers improved intra- and inter-observer reliability and a reproducible parameter extraction, which may be used in clinical routine and as objective surrogate end-points in clinical trials. 相似文献35.
36.
37.
We have investigated the metabolism and covalent binding of 1,1-dichloroethylene (1,1-DCE) in isolated unseparated lung cells and in enriched fractions of Clara and alveolar type II cells from mice. Lung cells from control mice separated by centrifugal elutriation were viable and metabolically active as assessed by measurements of 7-ethoxycoumarin deethylase, NADPH cytochrome c reductase, and glutathione S-transferase activities, which were highest in fractions enriched in Clara cells. Mice were treated with [14C]1,1-DCE (125 mg/kg; 20 microCi/kg) in vivo and, 1 hr later, lung cells were isolated and binding of [14C]1,1-DCE determined. Covalent binding was highest in the Clara cell fraction (480 +/- 205 pmol/10(6) cells; 41% Clara cell purity) when compared to the levels present in the fractions containing type II cells (126 +/- 63 pmol/10(6) cells; 51% type II cell purity) and mixed cells from whole lung (29 +/- 13 pmol/10(6) cells). Ultrastructurally, alveolar type II cells from lungs of control and 1,1-DCE-treated mice exhibited normal morphology with well-preserved lamellar bodies. Whereas Clara cells isolated from lungs of control mice appeared structurally unimpaired, those from the lungs of 1,1-DCE-treated mice displayed severe damage and disruption of cellular organelles. The results of these experiments demonstrate the highest binding of [14C]1,1-DCE-metabolite(s) in Clara cells, whereas significantly lower binding was found in both alveolar type II and unseparated lung cells. The substantial binding of [14C]1,1-DCE in Clara cells correlated positively with the high monooxygenase capacity and the preferential damage sustained by this cell population. 相似文献
38.
Distribution of cytochrome CYP2E1 in murine liver after ethanol and acetone administration. 总被引:2,自引:0,他引:2
P G Forkert T E Massey A B Jones S S Park H V Gelboin L M Anderson 《Carcinogenesis》1991,12(12):2259-2268
The effects of acetone and ethanol administration on cytochrome CYP2E1 in murine liver were investigated. A monoclonal antibody (Mab 1-98-1) specific to rat ethanol-inducible P450 recognized a major band of Mr 51,000 in Western immunoblots of mouse liver microsomes. This band was increased 1.8-fold by 10% ethanol in drinking water for 2 weeks, 4.7-fold by 1% acetone in drinking water for 1 week, and 2.5-, 2.1- and 6.8-fold by ethanol in a liquid diet for 9 days, 2 weeks and 3 weeks respectively. Immunohistochemical staining experiments with the same antibody showed specific localization in centrilobular regions of liver lobules, with variations in intensity that corresponded to differences detected in Western immunoblots. Uniform cellular increases in centrilobular staining occurred with all ethanol treatments, whereas a more heterogeneous increase in individual cells was noted after acetone. Lipid accumulation in hepatocytes was pronounced after 3 weeks on the ethanol liquid diet but was less so in other treatment groups, and thus did not consistently correlate with enzyme induction. Microsomal aniline p-hydroxylase activity was also induced by the acetone and ethanol treatments, with a progressive increase from 9 days to 3 weeks on the ethanol liquid diet. Changes in this activity in general paralleled those found with immunohistochemistry and immunoblotting. The results demonstrate that (i) the mouse is a good model for correlative biochemical and histochemical studies of CYP2E1 induction, (ii) in the mouse liver, this P450 is preferentially localized in centrilobular regions constitutively as well as in induced states, (iii) the centrilobular pattern varies under different induction conditions, and (iv) there is a progressive inductive increase in CYP2E1 protein and enzyme activity with chronic ethanol treatment over at least 3 weeks. 相似文献
39.
Although the relationship between abnormalities in the ECG and lung volumes has been well described in patients with chronic obstructive lung disease, little is known about this relationship in normal subjects. We investigated this relationship in normal, supine subjects at lung volumes ranging from residual lung volume to total lung capacity. We found that there was a significant right shift in the frontal axis with increasing lung volume. Over the precordium, R wave amplitude decreased mainly at the lateral leads and S wave amplitude increased chiefly at the anterior leads. These results are consistent with a normal vertical shift and clockwise rotation of the heart with increasing lung volume. 相似文献
40.
Nils Daniel Forkert Till Illies Einar Goebell Jens Fiehler Dennis Säring Heinz Handels 《International journal of computer assisted radiology and surgery》2013,8(5):775-786