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51.
对自能源减速器称重过程的动态性能进行机理研究,建立了称重动态过程的数学模型,并进行了仿真计算,仿真结果与实测吻合.在此基础上分析了溜放速度、容腔及管路内油液的可压缩性对称重结果的影响.首次提出了"完全称重"、"部分称重"、"重复称重"的概念,为减速顶的设计提供新的理论依据. 相似文献
52.
PURPOSE: To investigate the pattern of dopamine-beta-hydroxylase (DBH)-containing fibers in human and monkey eyes. METHODS: DBH-containing fibers were detected by immunohistochemistry. The primary antibody used recognized DBH, the key enzyme in the conversion of dopamine to noradrenaline. RESULTS: In the anterior segment, DBH immunoreaction product was found in the peripheral corneal endothelium layer, in both the dilator and sphincter muscles of the iris, as well as in the anterior border layer of the iris. The ciliary muscle and the stroma of the ciliary processes were also zones of concentration. In the posterior segment, staining was seen around blood vessels in the choroid, in the vascular walls of the short posterior ciliary arteries and in the ciliary nerves. The retina was also immunopositive, with specific labeling in cones and rods of photoreceptors, inner and outer plexiform layers and ganglion cell layer. There was no significant difference in the distribution of DBH-related immunoreactivity in human and monkey eyes. CONCLUSIONS: The localization of DBH-related immunoreactivity is generally consistent with the known physiological roles of noradrenaline. However, an apparently high concentration of the enzyme in the anterior border layer of the iris and in retinal photoreceptors raises questions about the possible role of DBH-containing fibers in these structures. 相似文献
53.
高效液相色谱—间接光度检测法同时测定血清和尿中5种氨基苷类抗生素 总被引:11,自引:0,他引:11
目的:建立一种直接分离测定体液中庆大霉素、丁胺卡那霉素、妥布霉素、西梭霉素和乙基西梭霉素等5种氨基苷类抗生素的高效液相色谱-间接光度检测(HPLC-IPD)法。方法:在流动相中加入具有紫外检测响应的检测剂烟酰胺,用紫外检测器直接测定紫外吸收很差的上述5种药物。C18固定相,流动相为含烟酰胺05mmol·L-1、庚烷磺酸钠5mmol·L-1和磷酸005mol·L-1的甲醇-乙腈-水(27∶18∶55)混合溶液。结果:血清和尿样平均回收率均大于96%,日内和日间RSD均小于6%。并测定了肌注此类药物病人的血清和尿样品。结论:该法适于体液中氨基苷类药物检测。 相似文献
54.
The aerial parts of Artemisia mongolica afforded the eudesmane derivative ludovicin B, two coumarins, umbelliferone and esculetin, two methoxylated flavones, eupatilin and pectolinarigenin, as well as a new eudesmane sesquiterpene, 6alpha,8alpha-dihydroxyisocostic acid methyl ester. Structures were elucidated by highfield 1D and 2D NMR techniques. 相似文献
55.
From the whole plants of Euphorbia petiolata, four new ingenane-type diterpenoids, 3,20-O-diacetylingenol 5-O-(2' E,4' Z)-tetradecadienoate (1), 5,20-O-diacetylingenol 3- O-(2' E,4' Z)-tetradecadienoate (2), ingenol 3-O-(2' E,4' Z)-tetradecadienoate (3), and 5,20-O-isopropylidenylingenol 3-O-(2' E,4' Z)-tetradecadienoate (4) were isolated. Their structures were elucidated by spectroscopic methods and chemical transformations. 相似文献
56.
Eudesmanolides and Other Constituents from Artemisia argyi 总被引:10,自引:0,他引:10
The phytochemical investigation of the aerial parts of ARTEMISIA ARGYI afforded beta-sitosterol, stigmasterol, alpha-amyrin, beta-amyrin, friedelin, naringenin, quercetin, and four eudesmane derivatives, two of which were new eudesmanolides. The structures of the novel compounds were elucidated by high field NMR techniques. 相似文献
57.
头针结合现代康复治疗小儿脑瘫临床研究 总被引:12,自引:1,他引:12
目的观察头针与现代康复疗法在治疗小儿脑瘫中的协同作用.方法90例脑瘫患儿随机分为3组,Ⅰ组采用头针疗法、Ⅱ组采用现代康复疗法和Ⅲ组采用头针结合现代康复疗法,治疗前后进行日常生活能力(ADL)、运动功能评定.结果经60天治疗后,3个组ADL评分明显高于治疗前(P<0.01),Ⅲ组的ADL评分、运动功能评分明显优于Ⅰ、Ⅱ组(P<0.01),Ⅰ、Ⅱ组相比则差异无显著性意义.结论头针与现代康复疗法在治疗小儿脑瘫中有协同作用. 相似文献
58.
经皮电刺激与电针治疗纤维肌痛综合征疗效对比 总被引:9,自引:1,他引:9
目的 :对比经皮电刺激与电针治疗纤维肌痛综合征 (FS)的疗效差异。方法 :将 66例患者随机分为经皮电刺激治疗组 (A组 )、电针治疗组 (B组 )、药物对照组 (C组 )进行临床疗效的对比研究。其中A组和B组均采用以FS常见的 1 8个压痛点邻近穴位为刺激点 ,C组采用口服阿米替林为主的西药。结果 :A组及B组的有效率及痊愈显效者 6个月、1 2个月及 2 4个月随访结果同C组比较 ,其差异具有非常显著性意义 (P <0 0 1 ) ,但A组同B组比较 ,差异无显著性意义 (P >0 0 5)。结论 :经皮电刺激或电针刺激穴位治疗纤维肌痛综合征的疗效优于药物组 ,而经皮电刺激是一种无创痛且被患者乐于接受的方法 相似文献
59.
Xiaoping Duan Zhichao Zhou Shu-Fang Jia Michael Colvin Elizabeth A Lafleur Eugenie S Kleinerman 《Clinical cancer research》2004,10(2):777-783
Cyclophosphamide (CY) and its derivative ifosfamide are alkylating agents used to treat osteosarcoma (OS). The purpose of these studies was to determine whether alkylating agents affect the expression of Fas ligand (FasL) and whether interleukin 12 enhances the sensitivity of human OS cells to alkylating agents. 4-Hydroperoxycyclophosphamide (4-HC), the preactivated CY compound, and 4-hydroperoxydidechlorocloclophosphamide (4-HDC), its nonalkylating analogue, human OS LM6 cells, and a clone of cells derived by transfection with the interleukin 12 gene (LM6-#6) were used for these studies. Incubation of LM6 and LM6-#6 with 10 micro M 4-HC increased the expression of FasL mRNA (2.5- and 3.0-fold, respectively). By contrast, 4-HDC, Adriamycin (ADR), cisplatin (CDP), and methotrexate (MTX) had no effect on FasL mRNA expression. Increased FasL expression after treatment with 4-HC was also demonstrated by immunohistochemistry and flow cytometry. Drug-induced FasL was functional and mediated cell death. We examined the effect of FasL up-regulation by 4-HC on LM6 and LM6-#6 cells. Flow cytometry showed that LM6-#6 cells expressed 2.2-fold more Fas than LM6 cells. Cytotoxicity of 4-HC, 4-HDC, ADR, CDP, and MTX on LM6, LM6-neo, and LM6-#6 were quantified. Colony-forming assay revealed an IC(50) of 2.10 micro M for 4-HC in LM6-neo cells compared with 0.41 micro M in LM6-#6 cells. The IC(50) for 4-HDC, ADR, CDP, and MTX were not significantly different between the two cell lines. We concluded that the increased expression of Fas enhanced LM6-#6 sensitivity to 4-HC. These data indicate that Fas/FasL may be involved in the cytotoxic pathway of CY. Combining biological agents with chemotherapeutic agents that have complementary Fas/FasL pathway actions may offer new therapeutic alternatives. 相似文献
60.
Elizabeth A Lafleur Nadezhda V Koshkina John Stewart Shu-Fang Jia Laura L Worth Xiaoping Duan Eugenie S Kleinerman 《Clinical cancer research》2004,10(23):8114-8119
PURPOSE: The process of metastasis requires the single tumor cell that seeds the metastatic clone to complete a complex series of steps. Identifying factors responsible for these steps is essential in developing and improving targeted therapy for metastasis. Resistance to receptor-mediated cell death, such as the Fas/Fas ligand pathway, is one mechanism commonly exploited by metastatic cell populations. EXPERIMENTAL DESIGN AND RESULTS: LM7, a subline of the SAOS human osteosarcoma cell line with low Fas expression, was selected for its high metastatic potential in an experimental nude mouse model. When transfected with the full-length Fas gene (LM7-Fas), these cells expressed higher levels of Fas than the parental LM7 cells or LM7-neo control-transfected cells. These cells were also more sensitive to Fas-induced cell death than controls. When injected intravenously into nude mice, the LM7-Fas cell line produced a significantly lower incidence of tumor nodules than control cell lines. Lung weight and tumor nodule size were also decreased in those mice injected with LM7-Fas. Levels of Fas were quantified in osteosarcoma lung nodules from 17 patients. Eight samples were Fas negative, whereas the remaining 9 were only weakly positive compared with normal human liver (positive control). CONCLUSIONS: Our results demonstrate that altering Fas expression can impact the metastatic potential of osteosarcoma cells. We conclude that the increase of Fas on the surface of the LM7 osteosarcoma cells increased their sensitivity to Fas-induced cell death in the microenvironment of the lung, where Fas ligand is constitutively expressed. Thus, loss of Fas expression is one mechanism by which osteosarcoma cells may evade host resistance mechanisms in the lung, increasing metastatic potential. Fas may therefore be a new therapeutic target for osteosarcoma. 相似文献