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31.
目的探讨CD26/DPPⅣ、半乳糖凝集素3免疫组织化学染色及其联合检测在甲状腺癌诊断中的应用价值。方法采用免疫组织化学EnVision二步法检测了114例良恶性甲状腺肿瘤组织中CD26/DPPⅣ及半乳糖凝集素3的表达。结果CD26/DPPⅣ及半乳糖凝集素3在正常甲状腺组织中无表达,在甲状腺腺瘤及滤泡癌中少有表达,在大多数甲状腺乳头状癌中呈不同程度的阳性表达。相对于甲状腺腺瘤而言,CD26/DPPⅣ诊断乳头状癌的敏感性、特异性、诊断准确率、阳性预测值、阴性预测值及kappa值分别为86.8%、97.2%、90.4%、98.3%.79.5%及0.80,半乳糖凝集素3分别为97.1%、91.7%、95.2%、95.7%、94.3%及0.89。结论CD26/DPPⅣ及半乳糖凝集素3均是甲状腺乳头状癌较为可靠的标志物,可以辅助常规的病理检查进行乳头状癌与腺瘤的鉴别诊断,它们在甲状腺滤泡癌诊断中的应用价值尚有待于进一步的研究。  相似文献   
32.
A factory survey was conducted in three provinces in China from 1985 to 1989. The time-weighted average toluene concentrations in breathing zone air were monitored by diffusive sampling, whereas hippuric acid (HA) concentrations in shift-end urine samples were measured by high performance liquid chromatography (HPLC). Exposed workers (456 men and women) were those for whom toluene (up to 548 ppm toluene) accounted for greater than or equal to 90% of total exposure (by vapor concentration in ppm), whereas 517 nonexposed controls were recruited from the same factories or from factories of the same region. There was a linear correlation between the intensity of toluene exposure and HA concentration in the shift-end urine. Comparison of the results with findings in the literature shows that the toluene-induced increase in urinary HA concentration among workers in China is significantly smaller than the published values, whereas HA concentrations in urine samples from nonexposed controls are comparable to the levels previously reported.  相似文献   
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Current MR meal markers may interfere with gastric motility and secretion restricting the use of MRI in the measurement of gastric physiology. We therefore evaluated Gd-DOTA as a liquid phase marker, in vitro by determining dissociation, and adherence to the solids, and in vivo by simultaneous MRI (0.35 T scanner, multiple T1-weighted sections of the upper abdomen) and double indicator (perfusion marker PEG 4000, meal marker 99mTc-DTPA) measurements of emptying and secretion, following ingestion of 500 ml 10% glucose. In vitro Gd-DOTA was stable at a pH > 2 with < 2% dissociation at 24 h during incubation with HCI. Dissociation during incubation with HCI was linearly dependent on H+ concentration (0.77 < pH < 2.02). Less Gd-DOTA was absorbed onto the solid phase than 99mTc-DTPA (25% cf 36%). in vivo Gd-DOTA marked gastric contents provided strong positive contrast. Similar emptying curves were observed with both MRI and double-indicator techniques (r = 0.987, P < 0.001). Gd-DOTA has the potential to be a useful liquid phase contrast agent in MR studies on gastric function.  相似文献   
35.
功能性便秘患儿胃肠传输时间的测定   总被引:1,自引:0,他引:1  
目的 :采用不透X线标志物测定功能性便秘患儿和正常儿童全胃肠传输时间口 盲传输时间 ,结肠传输时间及分段结肠传输时间的正常值 .方法 :通过口服不透X线标志物 ,用X线拍片法分别于 12 ,2 4和 4 8h摄腹部平片 ,测定 6 8名正常儿童全胃肠传输时间 (totalgastrointestinaltransittime,TGITT)、口 盲时间 (mouth intestinetransittime ,M ITT)和结肠传输时间 (colonictransittime ,CTT) .结果 :正常儿童及FC患儿的 5 0 %全胃肠、口 盲、全结肠传输时间分别为 (2 3.6± 1.6 )h ,(9.9± 1.4 )h ,(14 .8± 1.8)和 (80 .4± 2 .1)h ,(2 0 .7± 0 .6 )h ,(5 9.9± 2 .3)h .节段性结肠传输时间包括 :右半结肠传输时间 (rightcolonictransittime,RCTT) ;左半结肠传输时间 (leftcolonictransittime ,LCTT)和直肠乙状结肠传输时间 (rectosigmoidcolonictransittime,RSTT)分别为 (7.3± 1.1)h ,(3.4± 0 .8)h ,(4 .1± 1.2 )和 (2 0 .3± 1.2 )h ,(12 .8± 1.7)h ,(2 6 .8± 1.4 )h .结论 :正常儿童胃肠传输时间与正常成人和功能性便秘患儿比较有显著差异 (P <0 .0 1) .胃肠传输时间测定可了解全胃肠及各段的动力情况 ,对功能性便秘的诊断及评估治疗效果有实用意义  相似文献   
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T cells are known to develop a critical role in the pathogenesis of atopic dermatitis (AD) and bronchial asthma. T cells involved in AD express the skin homing receptor CLA, but no lung homing receptor has been identified in bronchial asthma. We compared different cell markers and the cytokine production in T cells from children with AD or bronchial asthma. We studied the involvement of CLA+ and CLA- T-cell subpopulations in these diseases. We studied 20 children with acute AD lesions, 15 with mild persistent asthma, and 15 non-atopic controls. All patients were sensitized to house dust mite (DP) and evaluated during the acute phase. Total and specific IgE were measured by immunoassay and the expression of different cell markers and the cytokine production was analyzed by flow cytometry in peripheral blood mononuclear cells. Total IgE was significantly higher in AD children and IgE to DP in the asthmatic children. There was a significant increase in CD25+ CD4+ cells in asthmatic children and in HLA-DR+ CD4+ and HLA-DR+ CD8+ cells in AD. In the CD4+ subsets, there was an increase in IL-13, IL-5 and TNF-alpha in AD compared to controls, a decrease in IFN-gamma in asthmatic children compared to controls, and an increase in IL-13, IL5, IL2, TNF-alpha, and IFN-gamma in the AD compared to asthmatic children. Changes in cytokine production were mainly detected in CLA+ cells in AD and in CLA- cells in asthma. Differences exist in total and specific IgE, activation markers, and cytokine patterns between AD children and children with asthma, with the former expressing a Th2 pattern whereas in asthmatic children we only detected a decrease in IFN-gamma. Moreover, the subpopulations (CLA+ vs. CLA-) expressing these changes were different, indicating that the underlying mechanisms in the two diseases are not exactly the same.  相似文献   
38.
目的 探讨部分肿瘤相关分子标志物免疫组织化学的表达与结直肠癌淋巴结转移的相关性.方法 应用免疫组织化学技术检测65例结直肠癌手术标本Ki-67、p53的表达情况,对照手术所见和手术标本的病理检查结果 ,研究这些肿瘤相关分子标志物与肿瘤的生物学特性如浸润和淋巴结转移等的关系.结果 65例结直肠癌手术标本Ki-67、p53免疫组织化学的表达与肿瘤肠壁浸润深度无明显相关性(P>0.05).Ki-67的表达及Ki-67标记指数的表达与淋巴结转移及Dukes分期有明显的相关性(P<0.01);p53标记指数的表达与淋巴结转移有相关性(P<0.05),与Dukes分期有明显的相关性(P<0.01).结论 作为反应细胞增殖活性的肿瘤相关分子标志物Ki-67,其免疫组织化学的表达程度可间接反映结直肠癌淋巴结转移状况,可能成为反映淋巴结转移的一个标志物.  相似文献   
39.
Background: Recently it has been suggested that the bronchospasm and hyperresponsiveness phenomena observed in asthma are secondary to the actions of the eosinophils; the purpose of this study was to evaluate the relationship between the peripheral number of eosinophils and various markers of disease activity in a group of asthmatics examined in childhood (mean age 10 years) and early adulthood (mean age 21 years). Methods: The relationship between eosinophil count and pulmonary function (FEV1), respiratory symptoms, bronchial responsiveness to histamine and diurnal variation in peak expiratory flow rate (PEF) was studied in 70 subjects with bronchial asthma, of whom 24 had intrinsic and 46 extrinsic asthma. Self-reported symptoms of asthma were graded on a scale from 0 to 5, where 0 = no symptoms within the preceding 12 months and 5 = daily including nocturnal symptoms, and histamine responsiveness was analysed by means of the dose-response slope (DRS). Results: In both childhood and adulthood, a direct correlation was found between blood eosinophil count and symptom score (r= 0.69, P< 0.001 and r= 0.58, P < 0.001, respectively), whereas inverse correlations were observed between number of eosinophils and FEV, % predicted (r= .0.75, P < 0.001 and r= 0.80, P < 0.001. respectively). Furthermore, in adulthood, eosinophil count was found to be significantly correlated to hisiamine responsiveness (log DRS) (r= 0.65, P < 0.001) and diurnal PEF variation (r= 0.81, P < 0.001); these correlations were also noted after dividing the subjects into intrinsic and extrinic asthmatics. In both groups of subjects a significant inverse correlation was also found between histamine responsiveness and pre challenge FEV1% predicted. The eosinophil count in childhood was weakly correlated to the symptom score in adulthood (r= 0.29, P < 0.02). Conlusions: This study showed a relationship between eosinophil count and seventy of asthmatic symptoms, level of pulmonary function, histamine responsiveness and diurnal variation in PEF in both intrinsic and extrinsic asthma; suggesting that the peripheral eosinophil count reflects asthmatic activity, and possibly the degree of inflammation in the airways, in both children and adults. Furthermore, a low number of eosinophils in childhood might be related to a relatively favourable prognosis with regard to symptoms of asthma in early adulthood.  相似文献   
40.
The clinical, radiological, and pathological features in 10 cases of ganglioglioma are described. The clinical data were derived from the patients' medical records, including a review of the age, sex, details of the presenting symptoms, radiological imagings, surgical intervention, and the clinical outcome. Age ranged from 1 to 66 years (mean 29); there were five males and five females. The tumors were located in the fronto-medial, bifrontal, temporal, temporo-basal, temporo-parieto-occipital, and parietal lobes; the 3rd ventricle; the cervicothoracic spinal cord; and the conus medullaris. The presenting symptoms were focal seizures, headaches, hemiparesis, paraparesis, and tetraparesis. In four patients, gross total resection was achieved and in the remaining six patients only subtotal resection was possible. Tumor recurrence occurred in three patients, 1 year, 14 months, and 2 years after the first operation. The histopathologic appearance of gangliogliomas showed a broad variation of the neuronal, glial, and stromal component. Studying proliferation characteristics, labeling for Ki-67 ranged from 0 to 13.7% (mean 4.1) and for PCNA from 0 to 32.1% (mean 20.4). Due to their favorable prognosis, early recognition and correct diagnosis are important in order to avoid progressive neurological deficits and unnecessary aggressive therapy. The application of immunohistochemistry for both neuronal (synaptophysin, NSE, NFP) and astrocytic (GFAP) cell markers, as well as proliferation markers, are recommended in the diagnostic setting for gangliogliomas. The treatment of choice is total surgical resection. The role of radio- and chemotherapy is still controversial.  相似文献   
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