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871.
Preparation of fungal material for microscopical examination of their conidiogenous structures is described below. A modification to the existing methods used coupled with a sporulation medium has proved to be simple to use and successful for the induction of sporulation and subsequent examination of conidiogenous structures in a range of xylariaceous species and in endophytic fungi.  相似文献   
872.
Leeflang P., Buys Janny and Blotkamp Coby. 1978. Studies on Trypanosoma vivax: comparison of parasitological diagnostic methods. International Journal for Parasitology8: 15–18. Parasitological methods for the diagnosis of Trypanosoma vivax infections in Nigerian cattle, including thin and thick blood smear and lymph gland smear examination, haematocrit centrifuge technique, hypotonie lysis test and mouse inoculation were evaluated. In 155 blood samples, thick film examination was significantly better than thin smear examination; in 126 samples, the haematocrit centrifuge technique was significantly superior over thin smear but not over thick film examination; when all six methods were applied in 52 samples, significant differences could only be demonstrated between mouse inoculation on one hand and thick film and gland smear examination, haematocrit centrifuge technique and hypotonie lysis test on the other hand, and between thin smear examination and hypotonic lysis test. It was shown that none of the tests was either satisfactory or sufficiently reliable to be used alone. The combination of either haematocrit centrifuge technique or thick film examination together with thin smear examination is recommended as most practical for the diagnosis of T. vivax infection under field conditions. The haematocrit centrifuge technique is also more advantageous because simultaneous estimation of the packed cell volume will evaluate the clinical condition of the herd. A comparison of the value of diagnostic methods for East and West African T. vivax was included in the present study.  相似文献   
873.
 A comparison was made between the murine anti-MUC1 antibody BC2 (which reacts with the peptide epitope APDTR) and the “humanised” antibody hCTMO1 from CellTech, which reacts with the MUC1 epitope RPAP. Preliminary studies demonstrated that hCTMO1 was a “good” antibody whereas BC2 was not. Various parameters were determined and conclusions reached. (a) Affinity: the affinity of hCTMO1 was 2.60×107M–1 and that of BC2 was 1.36×107M–1; we did not consider these numbers to be substantially different, although hCTMO1 was clearly of higher affinity than BC2. (b) On/off rate at 4°C: both antibodies bound effectively to the MUC-1 transfectant MOR5-CF2; the association rate for hCTMO1 was 3.8 times that of BC2 and the dissociation rate for BC2 was twice as fast as that of hCTMO1. (c) On/off rates at 37°C: at 37°C the association rate for hCTMO1 was greater than that of BC2. (d) Internalization: hCTMO1 was also more efficient at internalising bound antibody; 70% of bound hCTMO1 was internalised, whilst 6% of bound BC2 was internalised. From these studies it was clear that, while hCTMO1 was of similar affinity to BC2, the faster uptake and internalisation and lower off rate indicated that it was likely to be a superior antibody; this was proven in vivo. (e) Localisation: hCTMO1 bound much better in vivo than BC2 (68% compared to 28%). (f) Therapeutic experiments: BC2-idarubicin conjugates were essentially ineffective in eradicating tumours in mice whereas hCTMO1-idarubicin had a dramatic effect on breast cancer tumour cells growing in mice. We conclude that the simple measurements on/off rates and internalisation at 37°C are the most important parameters to use to determine antibody effectiveness, prior to embarking on clinical studies. Received: 29 January 1997 / Accepted: 13 May 1997  相似文献   
874.
The development of complexes that allow the monitoring of the release and distribution of fluorescent models of anticancer drugs initially bound to cobalt(III) moieties is reported. Strong quenching of fluorescence upon ligation to cobalt(III) was observed for both the carboxylate- and the hydroximate-bound fluorophores as was the partial return of fluorescence following addition of ascorbate and cysteine. The extent of the increase in the fluorescence intensity observed following addition of these potential reductants is indicative of the fluorophore being displaced from the complex by the action of ascorbate or cysteine, by ligand exchange. The cellular distribution of the fluorescence revealed that coordination to cobalt can dramatically alter the subcellular distribution of a bound fluorophore. This work shows that fluorescence can be an effective means of monitoring these agents in cells, and of determining their sites of activation. The results also reveal that the cytotoxicity of such agents correlates with their uptake and distribution patterns and that these are influenced by the types of ligands attached to the complex.  相似文献   
875.
《Endocrine practice》2023,29(6):428-435
ObjectiveTo develop and validate a risk stratification system for the prediction of malignancy in partially cystic thyroid nodules (PCTNs).MethodsWe retrospectively reviewed the sonography data of patients with PCTNs from 2 medical centers—Hangzhou Traditional Chinese Medicine Hospital and Hangzhou First People’s Hospital—from January 2020 to December 2021. The independent risk factors for malignant PCTNs were evaluated using the univariate and multivariate logistic regression analyses. The nomogram prediction efficiency was assessed using the area under the curve and calibration curves. The decision curve analysis was used to determine the clinical value of the predictive model.ResultsA total of 285 patients were enrolled in this retrospective study, and of 301 PCTNs, 242 were benign and 59 were malignant. Younger age, hypoechoic, irregular margin, and microcalcifications were found to be the independent risk factors for malignant PCTNs. The area under the curve, sensitivity, and specificity were 0.860, 77.1%, and 84.7% in the training data set and 0.897, 91.7%, and 87.0% in the external validation data set, respectively. The total point of nomogram was >161, which showed the best to predict malignancy in PCTNs.ConclusionOur findings demonstrated that the risk stratification system for the assessment of PCTNs showed good prediction capacities.  相似文献   
876.
1999~2007年皮肤科门诊浅部真菌发病及镜检情况分析   总被引:1,自引:1,他引:0  
目的了解广州地区1999~2007年间皮肤科门诊浅部真菌病发病的种类和构成比及流行病学特点。方法对临床拟诊为浅部真菌病者,取皮屑行10%KOH涂片进行真菌直接镜检。结果2002年后就诊人数及构成明显增加,近9a发病种类和构成没有明显变化。各种浅部真菌病中发病检出率占前3位的依次为体癣(34.3%)、手足癣(32.6%)、股癣(12.4%)。镜检阳性率排前3位的为马拉色菌毛囊炎74.9%、花斑糠疹55.5%、甲癣45.5%,总阳性率为34.3%。镜检阳性率受病种、性别、年龄、取材部位、疑似鉴别病例数量等因素影响。结论就诊人数与检出率呈逐年增加的趋势,1999~2007年间广州地区浅部真菌发病的种类和构成比无明显变化,目前直接镜检法在临床上仍不失为经济、简便易行的真菌学检查方法。  相似文献   
877.
A method is presented for histological examination of undecalcified ground sections of tooth roots affected with periodontal disease. The roots were placed in Karnovsky's fixative overnight, postfixed in 2% buffered osmic acid, and dehydrated in an ascending series of ethanol. The specimens were then infiltrated with propylene-oxide and Epon-Araldite resin, embedded in Epon-Araldite, and sections were prepared using a cutting and grinding system. The resulting ground sections were 8-12 μm thick. The sections were allowed to air dry at room temperature. When thoroughly dried, a coverglass was applied using resinous mounting medium DPX. The specimens were examined by phase-contrast microscopy. The method is useful for simultaneous examination of mineralized dental tissue and bacterial morphotypes covering the root surface of teeth involved with periodontal disease.  相似文献   
878.
ObjectiveIn our country, thyroid nodules are sonographically evaluated in health maintenance organization (HMO) imaging centers, and patients are referred to tertiary hospitals for ultrasound-guided fine-needle aspiration (FNA) biopsy when indicated. We evaluated the concordance in Thyroid Imaging Reporting and Data System (TI-RADS) classification reporting between these sites.MethodsWe conducted a retrospective cohort study reviewing the sonographic features of thyroid nodules evaluated both at the HMO and a large tertiary center between January 2018 and December 2019. The primary outcome was concordance between the TI-RADS classification at both sites. Additional endpoints included correlation of TI-RADS to the Bethesda category following FNA and correlation of TI-RADS with malignancy on final pathology at each site.ResultsThe records of 336 patients with 370 nodules were reviewed. The level of concordance was poor (19.8%), with 277 (74.8%) nodules demonstrating higher TI-RADS and 20 (5.4%) lower TI-RADS at the HMO compared to the hospital (P < .001; weighted κ = 0.120). FNA results were available for 236 (63.8%) nodules. The Bethesda category strongly correlated with the hospital TI-RADS (P < .001), yet not with HMO TI-RADS (P = .123). In the surgically removed 57 nodules, a strong correlation was identified between the malignancy on final pathology and TI-RADS documented at the hospital (P < .001), yet not at the HMO (P = .259).ConclusionsThere is poor agreement between TI-RADS classification on ultrasound performed in the HMO compared to a tertiary hospital. The hospital’s TI-RADS strongly correlated with the Bethesda category and the final risk of malignancy, unlike the HMO.  相似文献   
879.
摘要 目的:对比先天性心脏病胎儿与正常胎儿的产前超声差异,分析产前超声诊断结果与胎儿先天性心脏病的相关性及危险因素。方法:选取我院2018年12月到2020年12月共收治的80例有先天性心脏病胎儿的孕妇作为研究对象,将其分为观察组,另选取健康胎儿的80例孕妇进行对比研究,将其分为对照组,对所有孕妇进行彩色多普勒超声进行诊断,分析观察组超声诊断与最终结果,对比两组胎儿的超声诊断情况,并对孕期胎儿先天性心脏病的风险因素进行单因素与多因素logistic回归分析。结果:通过尸检和出生后随访最终确定结果与超声诊断结果对比无显著差异(P>0.05),超声诊断中有3例漏诊;由于卵圆孔直径大于6 mm、心内膜垫缺损(Endocardial cushion defect, ECD)和单心房胎儿没有正常的四腔心结构,因此无法进行腔室内径的测量,对其他观察组患儿进行测量之后发现,观察组患儿左心发育不全综合征(hypoplastic left heart syndrome, HLHS)的左心房与左心室、法洛氏四联症(Tetralogy of Fallot, TOF)右心室、室间隔缺损(Ventricular Septal Defect, VSD)右心室内径明显低于对照组(P<0.05);对可能造成胎儿先天性心脏病的高风险因素进行分析发现,两组孕妇的孕期早期服药、高龄产妇以及家族心脏病史情况对比差异显著,观察组明显更高(P<0.05);对所有因素进行赋值,其中"是"或"有"为1,"否"或"无"为0。通过logistic回归分析发现只有孕期早期服药和家族心脏病史为胎儿先天性心脏病的独立危险因素(P<0.05)。结论:对孕妇进行综合产前超声诊断胎儿先天性心脏病的准确率较高,与最终结果无明显区别;虽然高龄孕妇与胎儿先天性心脏病具有一定关系,但是只有孕期早期服药和家族心脏病史是胎儿先天性心脏病的独立危险因素。  相似文献   
880.
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