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151.
丹酚酸A对大鼠半乳糖性白内障形成的抑制作用   总被引:20,自引:0,他引:20  
业已证明,丹酚酸A有较强的抗氧化和清除自由基等多方面的作用。本实验用大鼠半乳糖性白内障模型,研究局部应用丹酚酸A对白内障形成的影响。结果表明,局部用0.05%的丹酚酸A(每日滴眼两次)对白内障的形成有一定的抑制作用,使白内障形成过程减缓。而且给药组动物晶体内过氧化氢和脂质过氧化产物(MDA)含量减少,蛋白巯基和总巯基增加。体外实验表明,丹酚酸A对醛糖还原酶有一定抑制作用。以上结果提示,丹酚酸A可通过不同途径抑制白内障的形成,对糖性白内障的防治有一定意义。  相似文献   
152.
Chromotropic acid and acetylacetone methods for qualitative determination of formaldehyde were tested in parallel on 48 commercial samples, with high-performance liquid chromotography (HPLC) implemented for quantitative measure. In addition, interference with the detection of formaldehyde was investigated by analyzing 12 other aldehydes and ketones, 7 essential oils and 3 polysorbates. Throughout this comparative study, the disadvantages of the chromotropic acid method, of which 2 variants were used, were delineated and we found that the acetylacetone test proved to be a more efficient screening method for formaldehyde detection in a clinical laboratory.  相似文献   
153.
大花紫玉盘中新多氧取代环己烯类的结构鉴定   总被引:3,自引:0,他引:3  
从番荔枝科紫玉盘属植物大花紫玉盘( Uvaria grandiflora Roxb.)根茎中分得4种新的多氧取代环己烯及已知化合物zeylenol,应用波谱分析、X-射线衍射、园二色谱和 Mosher 酯制备等手段确定了全部新化合物的结构及其绝对构型,分别命名为大花紫玉盘醇A(1),B(2),E(3)和F(4)。  相似文献   
154.
Background Since 1963, the Drug Safety Unit of the Dutch Inspectorate for Health Care (DSU) holds a voluntary reporting system. Objective To analyse all reports received in the years 1974 to 1994, registered as anaphylaxis or as a diagnosis that could contain cases of anaphylaxis. Methods All reports were classified as probable or possible anaphylaxis according to previously described criteria and the causal relationship between exposure and anaphylaxis was assessed. Results Nine hundred and ninety-two reports possibly concerning anaphylaxis were received between 1974 and 1994. Fifty-six were unclassifiable. The remaining 936 reports concerned 326 men and 610 women. Three hundred and forty-five reports were classified as anaphylaxis probable, 485 as anaphylaxis possible, and 106 as anaphylaxis unlikely by previously specified criteria. Drugs frequently associated with anaphylaxis (causal relationship certain or probable) were: glafenine (326 reports classified as anaphylaxis probable or possible), combination preparations with (propy)phenazone or propyphenazone/phenacetine (39), diclofenac (30), dextran (20), ibuprofen (14), floctafenine (12), allergen extracts (12), sulfamethoxazole with trimethoprim (12), and trimethoprim (11). There is probably substantial under-reporting as well as reporting bias in these data. Furthermore, many reports were classified as possible and not as probable anaphylaxis because the temporal relationship was unknown or not reported. Conclusion Drugs that caused anaphylaxis most frequently were glafenine, NSAID and certain antibiotics. Data from a voluntary reporting system such as the DSU are valuable as an early warning system for drugs that may induce anaphylactic reactions.  相似文献   
155.
浸泡疗法是蒙古族传统医学中的一类外治疗法,包括瑟必素疗法、矿泉疗法、药浴、喷酒法等。其历史悠久,在古代文献中(汉文或蒙古文)有所记载。它的起源与发展与蒙古高原游牧文化有着密切联系。  相似文献   
156.
本文报道了一系列N-[-1(2-苯乙基-4-甲氧羰基-4-哌啶基]-N-丙酰苯胺(4-甲氧羰基芬太尼)哌啶环1位取代衍生物的合成及其镇痛活性;讨论了结构与镇痛活性之间的关系。药理试验结果表明,大部分化合物具有典型的吗啡样镇痛活性,是一类作用极强的麻醉性镇痛剂。特别是哌啶环1位β-苯环被取代乙烯基替代的化合物具有相当或接近子母体化合物的镇痛活性。其代表物1321的镇痛活性(ED_(50)=0.005mg/kg ip,小鼠,热板法)略强于4-甲氧羰基芬太尼(ED_(50)=0.0063 mg/kg)。  相似文献   
157.
158.
The rate of cellular proliferation was studied in the neoplastic cells of a malignant angioendothelioma and in its inflammatory infiltrate by means of optical radioautography after incorporation ex vivo of tritiated thymidine. One third of the normal looking, as well as the atypical, endothelial cells were engaged in the cell cycle of proliferation. This large pool has been effectively suppressed during subsequent chemotherapy which resulted in partial regression of the neoplasm. The proliferative activity of the infiltrate was higher inside the neoplasm than at its periphery.  相似文献   
159.
Samples of brain from 15 prospectively tested women over 75 years of age, living in the same institution and with a Blessed test score between 0 and 28 were studied to evaluate seven different staining techniques for counting senile plaques and neurofibrillary tangles. The methods included Bielschowsky (modified by Yamamoto & Hirano, 1986), Cross, Gallyas, Naoumenko-Feigin, silver methenamine, Bodian coupled with luxol fast blue, and thioflavine S; these techniques were performed on contiguous slides of the first temporal gyrus (Brodmann's area 22). The cost, difficulty and variability of the methods were evaluated. Modified Bielschowsky method revealed both amyloid and neurites. Cross, Bodian and Gallyas stained neurites preferentially and were more sensitive for neurofibrillary tangles than for senile plaques. Silver methenamine revealed amyloid in much the same way as thioflavine S. The highest count of senile plaques and neurofibrillary tangles was obtained with the modified Bielschowsky method. Best correlations between density of senile plaques and Blessed test score were obtained with modified Bielschowsky impregnation, silver methenamine, and Bodian and those for neurofibrillary tangles, with modified Bielschowsky, Naoumenko-Feigin, and Gallyas methods. Naoumenko-Feigin impregnation, even if fitted to the linear model, revealed very few changes (four times less than modified Bielschowsky) and appeared to be insensitive. All the techniques except Naoumenko-Feigin, were equally able to distinguish two groups of cases, i.e. those affected by Alzheimer's disease and those not affected. A multiple regression analysis indicated that the statistical relationship between the density of changes, evaluated after the modified Bielschowsky method, and the Blessed test score could not be improved by the additional use of other staining techniques. These data have direct implications for the evaluation of diagnostic criteria in Alzheimer's dementia. In this study, modified Bielschowsky impregnation was found to give the most complete picture of the lesions and, as such, could be considered a reference method. This technique is, however, expensive and difficult to perform. It stains a large number of normal structures and the recognition of the lesions is more subjective than with other selective stains. It is therefore difficult to recommend this technique for routine use. Other techniques alone, or in combination, can be recommended but the diagnostic criteria should be adapted for each of them.  相似文献   
160.
A primary tumour of the right atrium with morphological, ultrastructural and immunohistochemical features of a synovial sarcoma is described. This appeared to have arisen from a benign so-called mesothelioma of the atrio-ventricular node and had metastasized to the lungs. The histogenesis and relationship of these two tumours are discussed.  相似文献   
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