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91.
目的 :探索白细胞介素 6 (interleukin 6 ,IL 6 )增强乳腺癌细胞表达乳腺癌抗原 (CA15 3)和癌胚抗原 (CEA)的作用。方法 :将含IL 6蛋白编码顺序1176bpcDNA插入Pci neo哺乳动物表达载体。将重组载体转染MCF 7乳腺癌细胞 ,采用ELASA方法测定细胞培养上清液内IL 6浓度 ,用MEIA(microp articalenzymeimmunoassay)方法测定上清液中肿瘤相关抗原CA15 3、CEA和CA12 5。结果 :含有外源IL 6基因的MCF 7细胞分泌IL 6浓度 (338.5±2 2 .6pg·10 -6细胞 )明显高于父本没有含外源基因的MCF 7细胞 (2 5 .4± 4 .6pg·10 -6细胞 )和仅含空载体Pci neo的MCF 7细胞 (19.6± 3.0pg·10 -6细胞 ) (P<0 .0 1)。细胞培养d 3后 ,带外源IL 6基因的MCF 7细胞培养上清液中CA15 3和CA12 5水平 (分别为 14 .9± 2 .3和 38.8± 5 .1μg·10 -6细胞 )明显高于父本 (分别为 6 .6± 1.5和 10 .0± 1.6 μg·10 -6细胞 )和空载体Pci neo的MCF 7细胞 (分别为 3.4±0 .7和 14 .6± 2 .2 μg·10 -6细胞 ,P <0 .0 5 )。而转染IL 6基因没有明显改变CEA表达 (P >0 .0 5 )。结论 :IL 6具有诱导肿瘤相关抗原的表达和增强肿瘤细胞的免疫原性的作用 ,提示IL 6可能增强机体对肿瘤的免疫反应性。  相似文献   
92.
股内侧肌穿支皮瓣的解剖学基础与膝周创伤修复   总被引:4,自引:0,他引:4  
目的:探讨股内侧肌穿支皮瓣的解剖学特征,为临床膝周软组织缺损的修复提供一种新的术式。方法:实验于2005-01/10在解放军南京军区福州总医院军区临床解剖学研究中心实验室完成。30侧动脉内灌注红色乳胶的成人下肢标本由南京军区福州总医院军区临床解剖学研究中心提供。30侧成人下肢标本,以收肌结节、髌骨中点、腹股沟韧带中点为观测标志,重点解剖观测股内侧肌肌支的起源、走行、分支、分布及其远端吻合情况。一侧新鲜标本上,摹拟术式设计。结果:在股三角尖部自股动脉恒定发出的股内侧肌支,入肌门后在肌内沿肌束行向外下方,直至髌旁并与髌周动脉环相吻合。沿途除发出肌支营养股内侧肌外,还发出1~3支(77%为1支)、外径0.5~0.9mm肌皮穿支垂直穿过股内侧肌达深筋膜,并浅出至股内侧肌表面皮肤。皮瓣切取面积可达8.5cm×15.0cm。结论:可形成的以股内侧肌肌支-穿支逆行皮瓣转位可修复膝部软组织缺损。  相似文献   
93.

Background  

The effectiveness of collaborative care for patients with major depressive disorder in primary care has been established. Assessing its cost-effectiveness is important for deciding on implementation. This review therefore evaluates the cost-effectiveness of collaborative care for major depressive disorder in primary care.  相似文献   
94.
研究阿司匹林锌的化学合成方法。方法:以阿司匹林和硫酸锌为原料,经两步反应合成阿司匹林锌。结果得到的样品经IR、NMR、MS等波谱分析及元素分析、热分析证明该化合物为阿司匹林锌。总收率为80%。结论该合成方法收率稳定,合成周期短,合成路线完全可行。  相似文献   
95.
Background Elective radiation of lower neck is controversial for nasopharyngeal carcinoma (NPC) without lymph node metastasis (N0 disease).Tumor volume is an important prognostic indicator.The objectiv...  相似文献   
96.

Background

Preoperative radiotherapy of the pelvic abdomen presents with complications mostly affecting the small bowel. The aim of this study was to define the features of early radiation-induced injury on small bowel.

Methods

54 mice were divided into two groups (36 irradiated and 18 sham irradiated). Animals were placed on a special frame and (in the radiated group) the exteriorized segment of ileum was subjected to a single absorbed dose of 19 or 38 Gy radiation using 6 MV high energy photons. Specimens were collected for histology, immunohistochemistry (IHC) and ELISA analysis after 2, 24 and 48 hours. Venous blood was collected for systemic leucocyte count in a Burker chamber.

Results

Histology demonstrated progressive infiltration of inflammatory cells with cryptitis and increased apoptosis. MIP-2 (macrophage inflammatory protein) concentration was significantly increased in irradiated animals up to 48 hours. No significant differences were observed in IL-10 (interleukin) and TNF-α (tumour necrosis factor) levels. IHC with CD45 showed a significant increase at 2 hours of infiltrating leucocytes and lymphocytes after irradiation followed by progressive decrease with time. Caspase-3 expression increased significantly in a dose dependent trend in both irradiated groups up to 48 hours.

Conclusion

Acute small bowel injury caused by local irradiation is characterised by increased apoptosis of crypt epithelial cells and by lymphocyte infiltration of the underlying tissue. The severity of histological changes tends to be dose dependent and may affect the course of tissue damage.  相似文献   
97.
Bone tumors: magnetic resonance imaging versus computed tomography   总被引:7,自引:0,他引:7  
The magnetic resonance (MR) imaging characteristics of bone tumors are described and the clinical utility of MR imaging in patient evaluation is reported. Fifty-two patients with skeletal lesions were examined with a Picker MR imager (0.15-T resistive magnet). Twenty-five patients had primary malignancies, seven had benign bone neoplasms, 15 had skeletal metastases, and five had neoplasm simulators. Forty-five patients had CT scans available for comparison. For demonstrating the extent of tumor in marrow, MR was superior to CT in 33% of cases, about equal to CT in 64%, and inferior to CT in 2%. For delineating the extent of tumor in soft tissue, MR was superior to CT in 38% of cases and about equal to CT in 62%. CT was superior in all cases for demonstrating calcific deposits and pathologic fractures. In four patients with metal prostheses or surgical clips, MR was superior to CT in documenting recurrent tumor because of artifactual degradation of the CT image. Direct sagittal and coronal images from MR permit accurate assessment of the relationship of tumor to adjacent normal structures, including the physis, joints, and neurovascular structures. MR is useful in the evaluation of bone tumors: it is of greatest value in evaluations of the peripheral skeleton, the medullary canal, soft tissues, and postoperative tumor recurrence. With a 0.15-T magnet, MR is less useful in the evaluation of the axial skeleton and cortical bone.  相似文献   
98.
99.
Orexin receptor antagonism represents a novel approach for the treatment of insomnia that directly targets sleep/wake regulation. Several such compounds have entered into clinical development, including the dual orexin receptor antagonists, suvorexant and almorexant. In this study, we have used equilibrium and kinetic binding studies with the orexin-2 (OX2) selective antagonist radioligand, [3H]-EMPA, to profile several orexin receptor antagonists. Furthermore, selected compounds were studied in cell-based assays of inositol phosphate accumulation and ERK-1/2 phosphorylation in CHO cells stably expressing the OX2 receptor that employ different agonist incubation times (30 and 5 min, respectively). EMPA, suvorexant, almorexant and TCS-OX-29 all bind to the OX2 receptor with moderate to high affinity (pKI values ≥ 7.5), whereas the primarily OX1 selective antagonists SB-334867 and SB-408124 displayed low affinity (pKI values ca. 6). Competition kinetic analysis showed that the compounds displayed a range of dissociation rates from very fast (TCS-OX2-29, koff = 0.22 min−1) to very slow (almorexant, koff = 0.005 min−1). Notably, there was a clear correlation between association rate and affinity. In the cell-based assays, fast-offset antagonists EMPA and TCS-OX2-29 displayed surmountable antagonism of orexin-A agonist activity. However, both suvorexant and particularly almorexant cause concentration-dependent depression in the maximal orexin-A response, a profile that is more evident with a shorter agonist incubation time. Analysis according to a hemi-equilibrium model suggests that antagonist dissociation is slower in a cellular system than in membrane binding; under these conditions, almorexant effectively acts as a pseudo-irreversible antagonist.Linked ArticlesThis article is part of a themed section on Orexin Receptors. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-2  相似文献   
100.
The objective of this study was to set up a superovulation protocol in adult cyclic rats by using recombinant human follicle stimulating hormone (rhFSH; Org32489). Good results were obtained by treatment with decreasing doses of rhFSH (2.5 to 0.5 IU) during the dioestrus period. The number of corpora lutea (CL) found in rats treated with this protocol was 43.5 +/- 3.4; this is more than three times the number in saline-treated control rats (13.0 +/- 0.4). Fertilization of oocytes after superovulation was as good as after normal ovulation in terms of number of 2-cell stage embryos found 2 days after mating. The absolute number of implantations was twice the number observed in saline-treated control rats (23.3 +/- 1.8 versus 10.6 +/- 0.5); therefore the number of implantations per CL was lower in superovulated rats. The serum concentrations of luteinizing hormone (LH), endogenous FSH and oestradiol-17beta were decreased during rhFSH treatment, while the inhibin serum concentration was increased. The progesterone serum concentration was increased on the days of pro-oestrus and oestrus after treatment. No difference was observed in the testosterone serum concentration. Pretreatment with 10 IU rhFSH at oestrus before giving the decreasing doses of rhFSH during dioestrus reduced the ovulatory response. Finally, treatment with a constant low dose of rhFSH instead of a decreasing dose of rhFSH did not result in spontaneous ovulation. However, ovulation induction by means of a human chorionic gonadotrophin bolus resulted in superovulation in six out of eight rats. It is concluded that superovulation in cyclic rats can be achieved using rhFSH treatment. However, it was found that the type of rhFSH regimen was very important to achieve appropriate stimulation. The optimal protocol was treatment with decreasing doses of rhFSH during dioestrus. The oocytes retrieved could be fertilized as well as oocytes of saline-treated control rats. The results also indicate that treatment with higher doses of rhFSH might induce a desensitization for FSH and LH.   相似文献   
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