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1.
To detect neuronal cell bodies whose axon projects to the hypothalamic supraoptic nucleus, small volumes (10-50 nl) of 30% horseradish peroxidase or 2% fast blue solutions were pressure-injected into the area of one supraoptic nucleus of rats. Both dorsal and ventral approaches to the nucleus were used. In animals where the injection site extended beyond the limits of the supraoptic nucleus, retrogradely labelled cell bodies were found in many areas of the brain, mainly in the septum, the nucleus of the diagonal band of Broca and ventral subiculum in the limbic system; the dorsal raphe nucleus, the locus coeruleus, the nucleus of the dorsal tegmentum, the dorsal parabrachial nucleus, the nucleus of the solitary tract and the catecholaminergic A1 region in the brain stem; in the subfornical organ and the organum vasculosum of the lamina terminalis, as well as in the median preoptic nucleus. In contrast, when the site of injection was apparently restricted to the supraoptic nucleus, labelling was only clearcut in the two circumventricular organs, the median preoptic nucleus, the nucleus of the solitary tract and the A1 region. Injections of wheat germ agglutinin coupled with horseradish peroxidase (60-80 nl of a 2.5% solution) made in the septum and in the ventral subiculum anterogradely labelled fibers coursing in an area immediately adjacent to the supraoptic nucleus but not within it. In contrast, labelling within the nucleus was found following anterograde transport of tracer deposited in the A1 region and in an area that includes the nucleus of the solitary tract. Neurones located in the perinuclear area were densely labelled by small injections into the supraoptic nucleus; they may represent a relay station for some afferent inputs to the supraoptic nucleus. These results suggest that the supraoptic nucleus is influenced by the same brain areas which project to its companion within the magnocellular system, the paraventricular nucleus.  相似文献   
2.
目的 探讨髋、膝关节手术病人血栓前状态和血液中凝血-纤溶系统的变化.方法 每组病人术前及术后1、4、7、10天检测TAT、PAP、血凝常规等指标;术前及术后第7天~10天应用彩色多普勒超声仪监测DVT.结果 ①手术组共有18例(40.9%)术后并发DVT,保守组共有9例(22.0%)并发DVT,对照组无DVT发生;②手术组术后并发DVT者术前及术后TAT均显著升高,而PAP水平较低;③术后并发DVT者与术前PAP/FB比值相关.结论 ①术前TAT检测可作为术后是否并发DVT的一项较有意义的预测指标.②术前较低的纤溶水平可能成为髋、膝关节置换术后DVT发病率高的原因之一.③术前血浆PAP/FB比值有望成为预测术后DVT的有用指标.  相似文献   
3.
The regulation of extracellular matrix (ECM) by retinoic acid (RA) is interesting in light of the fact that the ECM plays an essential role in morphogenesis and palatal shelf elevation. In the current study, we explored the effect of RA overexposure on ECM and the probable mechanisms in cultured human fetal palate mesenchymal cells (hFPMCs). RA dose-dependently inhibited cell proliferation and mRNA and protein levels of ECM components fibronectin, tenascin C and fibrillin-2. Zymography revealed that MMP-2 activity was suppressed by RA. Further analysis revealed that mRNA levels of MMP2 and TIMP2 were decreased, while the MMP2/TIMP2 mRNA ratio was increased, which might facilitate the ECM degradation. Because of the pivotal role of TGF-β/Smad pathway in palatogenesis we therefore checked the effect of RA on TGF-β/Smad signaling. The results indicated RA treatment increased Smad7 expression and decreased the levels of TGF-β1, TGF-β3, TGF-β type II receptor (TβRII) and phosphorylated Smad2 and Smad3. Activation of the Smad pathways by either exogenous TGF-β3 or recombinant adenoviruses for Smad3 attenuated RA-induced inhibition of cell proliferation and ECM components and rescued the RA-altered MMP2/TIMP2 mRNA ratio. In conclusion, these findings suggested that RA overexposure inhibited cell proliferation and disrupted the ECM network through down-regulation of TGF-β/Smad pathway.  相似文献   
4.
Endobronchial ultrasound   总被引:11,自引:0,他引:11  
Sheski FD  Mathur PN 《Chest》2008,133(1):264-270
During flexible fiberoptic bronchoscopy (FB), a solitary pulmonary nodule (SPN) is sampled by means of transbronchial needle aspiration (TBNA), brush, or transbronchial lung biopsy under fluoroscopy; and mediastinal lymph nodes are sampled using "blind" TBNA. Endobronchial ultrasound (EBUS) was developed to help visualize the lesion at the time of biopsy in order to improve the diagnostic yield. METHODS: There are two types of EBUS techniques: using a radial probe (RP) with a rotating transducer at the distal tip, which produces a 360 degrees image to the long axis of the bronchoscope; and using an EBUS bronchoscope with a linear transducer at its distal tip, producing a 50 degrees image parallel to its long axis. RESULTS: In biopsies of SPNs < 2 cm using an RP, EBUS demonstrates a higher diagnostic yield than conventional FB techniques. With mediastinal and hilar nodal stations, except for the subcarina, EBUS shows a higher yield over blind TBNA. The current procedural terminology code for EBUS is 31620, a "ZZZ" code submitted in addition to other performed procedures (31622-31638). In 2007, an estimate of physician Medicare reimbursement for EBUS is $70.49. Reimbursement is locality dependent and based on economic-exchange conversion factors. Incorporating an ultrasound image into the report substantiates the use of this technique. Limitations: The physician must learn ultrasound image interpretation and the EBUS technique, and be skilled in TBNA. Maintaining competency requires frequent performance of EBUS. CONCLUSION: EBUS-directed biopsy improves the yield over conventional FB for SPNs < 2 cm and for most mediastinal or hilar nodal stations. This reduces the need to conduct additional diagnostic procedures.  相似文献   
5.
The benchmark dose (BMD) approach is being increasingly used in the area of food risk assessment because it offers several advantages compared to the conventional no-observed-adverse-effect-level approach. The aim of this work was to check the applicability of the BMD approach on toxicity data available from pesticides, mycotoxins and natural toxins.  相似文献   
6.
Selective visualization of collaterals of corticospinal and pyramidal fibres to the pons in cat was obtained by retrograde transport of the fluorescent tracer fast blue (FB) through the stem fibres. Unilateral FB injections in the cervical cord and the pyramidal tract respectively produced soft blue fluorescent labelling of pyramidal fibres and of fibres and structures resembling 'terminals' in the pontine grey: contralateral to the spinal injections and ipsilateral to the pyramidal injections. These labelled elements were concluded to represent collaterals of corticospinal and pyramidal fibres because (a) their distribution corresponded to that of the pericruciate corticopontine fibres, (b) their labelling was prevented when the FB injections were preceded by a transection of either the cerebral peduncle or the pyramidal tract which lesions also prevented the FB labelling of the distal parts of the transected axons. Similar findings were obtained when using wheat germ agglutinin-horseradish peroxidase. In other experiments FB-labelling of pyramidal collaterals was combined with retrograde labelling of pontine neurones projecting to the contralateral anterior lobe of the cerebellum using diamidino yellow dihydrochloride as the second tracer. The distributions of the retrogradely labelled neurones and of the pyramidal collaterals in the pontine grey showed an almost complete overlap indicating that these collaterals mainly establish connections with the cerebellar anterior lobe.  相似文献   
7.
8.
After injections of fast blue into the rostral cortex and Evans blue into the caudate nucleus in cats, doubly labeled neurons were present in the ventral anterior, ventral lateral, rhomboid, and mediodorsal thalamic nuclei. Doubly labeled cells were also found in most members of the intralaminar group, including the central medial, paracentral, central lateral, and parafascicular nuclei. Although the centromedian nucleus contained large numbers of cells labeled with Evans blue which project to the caudate nucleus, and a few fast-blue labeled cells which projected to the cortex, doubly labeled neurons were absent from this posterior intralaminar nucleus in this study.  相似文献   
9.
BackgroundVulvovaginal candidiasis (VVC) is a common vaginitis in females. The commonly used diagnostic method, 10% potassium hydroxide (KOH) smear microscopy, makes it not very easy to recognize fungi.MethodsVaginal secretions were collected from clinically suspected VVC patients and divided into four groups and examined using KOH, CFW (Calcofluor White), FB 85(fluorescent brightener 85), and culture. The data were statistically analyzed.ResultsIn total, 110 patients with suspected VVC were recruited. The positive rates of KOH, CFW, FB 85, and the culture method were 68.2%, 64.5%, 61.8%, and 77%, respectively. According to the McNemar test, there was no statistically significant difference between the KOH, CFW, and the FB 85 methods (p > 0.05). However, CFW had a shorter diagnosis time than the KOH method and had a statistically significant difference (p < 0.001). Moreover, CFW has the highest sensitivity, specificity, and accuracy. In morphological recognition, it was easier to recognize fungal structures with CFW and FB 85 than with the KOH.ConclusionsThe fluorescent method is a good method for the diagnosis of VVC. And the fungi can be found more quickly. Similar to CFW, FB 85 is also a potential good fluorescent reagent for the diagnosis of VVC and has potential value for application in clinical fungal infection diseases.  相似文献   
10.
Two Lactobacillus strains, L. plantarum B7 and L. pentosus X8, exhibited high efficiency in removing fumonisins (FB1 and FB2) from aqueous medium. 52.9% FB1 and 85.2% FB2 were bound by L. plantarum B7, and 58.0% FB1 and 86.5% FB2 by L. pentosus X8, respectively. Temperature, incubation time, and pH affected the binding ability of two strains. Cell viability was not necessary for the binding ability. The various components of cell wall were determined for their ability to absorb FBS. The results revealed that the intact peptidoglycans exhibited the greatest capacity in binding FBs. Especially the better structural integrity of the peptidoglycans the more FBs was bound. Thus, the absorption of two bacterial cells to FBs is proposed to be a physical process, and peptidoglycans should be the main binding site. Additionally, Caco-2 cell lines were used to evaluate the ability of the two strains to reduce the damage of FBs in vitro. Caco-2 cell's death was reduced after the cell lines were subjected to both viable and non-viable L. pentosus X8, respectively. The two Lactobacillus strains might be used as a biological detoxification for the removal of FBs from diet and feed in the future.  相似文献   
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