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1.
Compared with results obtained in locally anesthetized, paralyzed rats, the dissociative anesthetic ketamine did not alter either the number of spontaneously active striatal neurons or the basal firing rate of striatal neurons; 90% of these cells exhibited the type I striatal neuron waveform. Chloral hydrate anesthesia suppressed both the occurrence and the firing rate of spontaneously active type I cells, but did not alter the activity of type II striatal neurons. Cortical stimulation preferentially activated type II cells in paralyzed rats and in chloral hydrate-anesthetized rats. Thus, under dissociative anesthesia it is possible to study spontaneously active type I striatal neurons. However, a method of activation such as cortical stimulation is necessary to study type II striatal neurons.  相似文献   
2.
We examined records of sedations provided by the paediatric anaesthesiology staff for 455 children (ages 1 mo-17 yr) undergoing MRI or CT scans at our institution over a twelve-month period with regard to the monitoring of adverse events: excessive sedation, agitation, vomiting, hypoxaemia, and major airway compromise. One hundred-and-thirty-one patients (29%) received chloral hydrate; 324 patients (71%) received propofol. All patients were monitored with continuous noninvasive pulse oximetry and received supplemental oxygen via nasal cannulae. Of the patients who received chloral hydrate, 64 (49%) were over one year of age; of the patients who received propofol, 318 (98%) were one year of age or older. In the chloral hydrate group, 23 patients (19%) were deemed excessively sedated and four patients (3%) were agitated; no patients in the propofol group experienced any of the adverse outcomes reviewed. Furthermore, no patients in either group had significant airway compromise and none was admitted to the hospital as a result of the sedation.  相似文献   
3.
以Fe~(3+)代替Pd-C和Raney Ni为催化剂、水合肼为供氢体、3,3′-二硝基-4,4′-二氨基二苯醚为受氢体、甲醇为溶剂,进行催化转移氢化反应,产物3,3′,4,4′-四氨基二苯醚(TADPO)质量好,得率可达80%。此外,还对反应温度、时间、以及水合肼、催化剂、溶剂用量,水合肼浓度、催化剂重复使用等影响因素进行了研究,获得了较佳工艺条件。本法制得的TADPO与均苯四甲酸二酐缩聚可制得性能良好的聚眯唑吡咙。  相似文献   
4.
A relatively nonhygroscopic crystalline form of the glycopeptide, N-acetylmuramyl-L--aminobu-tyryl-D-isoglutamine (I), containing approximately one molecule of water was prepared from amorphous material. The crystalline material, consisting of a mixture of the and anomers, exhibited better physical and chemical stability than the lyophilized amorphous material. The /-anomer ratios of I in both the crystalline and the amorphous state were approximately equal but different from that in solution.  相似文献   
5.
潘萌  蒋浩琴  周芸  郑捷 《现代免疫学》2006,26(2):98-101
为研究、比较不同佐剂对诱导小鼠产生获得性免疫应答的不同作用,以卵清白蛋白(OVA)为抗原,分别混合完全弗氏佐剂(CFA)或Al(OH)3佐剂,对C57BL/6小鼠进行常规免疫,采用流式细胞技术对细胞内细胞因子IFN-γ和IL-4进行检测;ELISA方法对特异性抗OVA抗体滴度及抗体亚型进行了检测。结果显示在免疫后CFA组产生以IFN-γ为主的细胞因子而Al(OH)3组产生以IL-4为主的细胞因子;两组中均产生特异性抗OVA IgG抗体,但CFA组以IgG2a亚型为主,而Al(OH)3组则以IgG1亚型为主,不产生IgG2a亚型抗体。实验表明,经CFA加抗原免疫后机体产生的免疫应答以Th1型细胞免疫为主,抗体类型为IgG2a;而Al(OH)3佐剂则诱导机体产生Th2型细胞免疫应答,抗体类型为IgG1。  相似文献   
6.
An oxidimetric titrant, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone in anhydrous acetic acid is used for the semimicro-determination of hydrazine hydrate, phenylhydrazine hydrochloride, isoniazid and iproniazid phosphate in pure forms as well as in some pharmaceutical preparations containing isoniazid and iproniazid phosphate. The end point was detected potentiometrically using a platinum-calomel combination electrode. The results obtained are compared statistically with those obtained by the official methods and they are in good agreement.  相似文献   
7.
微米黄连的溶出性研究   总被引:1,自引:1,他引:1  
徐丽君  陆付耳  邹欣  魏世超 《医药导报》2004,23(6):0377-0379
目的:研究黄连3种微粒的溶出性。方法:选用3因素(粒径、加水量、溶出时间)、3水平正交设计试验,用苦味酸离子对萃取法测定黄连中的季铵碱溶出量。结果:粒径6.4~57.0 μm的微粉,5 min,45倍水量溶出性能最佳,粒径<6.4 μm的微粉溶出性较差。结论:粒径6.4~57.0 μm的黄连微粉直接应用于临床具有重要意义。  相似文献   
8.
Trichloroethylene (TCE) is a prevalent occupational and environmental contaminant that has been reported to cause a variety of toxic effects. Here, we have undertaken studies to test the hypothesis that TCE exposure adversely affects sperm function and fertilization. Sperm retrieved from mice exposed to TCE (1000 ppm) by inhalation for 1 to 6 weeks were incubated in vitro with eggs isolated from superovulated female mice. The number of sperm bound per egg was significantly decreased when mice were exposed to TCE for 2 and 6 weeks but not at exposures of 1 and 4 weeks. In vivo fertilization was also determined in superovulated female mice mated with males exposed to TCE for 2 to 6 weeks. The percentages of eggs fertilized, as assessed by the presence of two pronuclei, were significantly decreased after 2 and 6 weeks of TCE exposure. A slight but insignificant decrease was observed after 4 weeks of TCE exposure. The direct effects of TCE and its metabolites, chloral hydrate (CH) and trichloroethanol (TCOH), on in vitro sperm-egg binding were also investigated. Sperm-egg binding was significantly decreased when sperm were pretreated with CH (0.1-10 microg/mL). Significantly lower levels of sperm-egg binding were also detected with TCOH (0.1-10 microg/mL), although the decreases were not as pronounced as those for CH. These results showed that TCE exposure leads to impairment of sperm fertilizing ability, which may be attributed to TCE metabolites, CH, and TCOH.  相似文献   
9.
Glycidol fatty acid esters (GEs) are found in refined edible oils. Safety concerns have been alleged due to the possible release of glycidol (G), an animal carcinogen.  相似文献   
10.
ObjectiveTo establish quality control parameters of a locally occurring medicinal plant, Malva parviflora which is utilized as folk medicine in Sialkot area in Pakistan.MethodsIn pharmacognostic studies different types of evaluations were carried out that focus on microscopic, macroscopic, fluorescence analysis and organoleptic evaluations.ResultsThe distinguishing characters of stem were the presence of parenchyma, cork cells, irregular shape calcium oxalate crystals, simple and compound starch granules and fusiform fibers with pits. Root microscopic characters were presence of simple and spherical starch granules with rounded or slit hilum, groups of lignified xylem fibers, reticulate vessels, and sieve tissues. Leaves microscopy indicated the presence of paracytic stomata, lignified fibers having pits, spiral and annular vessels, numerous sclereids while in fruit microscopy epicarp, thin walled cells endocarp, thin walled parenchyma and collenchyma of mesocarp and abundant thick walled endospermic cells containing aleurone grains and micro rosette crystals. Macroscopic study of leaves showed, 5-7 lobed reniform-shape, glabrous-surface, reticulate-venation in the leaves. Macroscopic features of roots showed type of root-taproot, surface-glabrous and stem was 1-10 dm tall simple to branched and may be prostrate or ascending. Similarly fruit was of schizocarp type.ConclusionsThis study provides the scientific data for the proper identification and establishment of standards for the use of Malva parviflora.  相似文献   
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