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1.
生物活性陶瓷与细胞外基质骨形成对Ca、P、ALP影响   总被引:2,自引:0,他引:2  
目的:通过钙(Ca)、磷(P)及碱性磷酸酶(ALP)评价,探讨生物活性陶瓷及细胞外基质与骨细胞相互作用机理,为骨替代材料成骨效应提供依据。方法:选用多种材料进行蒸馏水及血浆接触,体外成骨细胞培养及体内骨诱导试验。采用原子吸收,钼蓝比色及速率法分析化学性能,血浆、细胞冻溶液及组织匀浆中Ca、P、ALP的变化规律。结果:材料组体内、外接触Ca、P、ALP值高于对照组。细胞外基质复合材料组高于相应的非复合材料组。TGF-β1加材料高于BMP复合材料组,而不同材料有所不同,TCP材料高于其它材料。结论:生物活性陶瓷材料均有不同程度的Ca、P离子释放,细胞外基质及Ca、P离子可提高成骨细胞活性,异位骨形成及ALP活性。  相似文献   
2.
本研究采用亚急性汞中毒肾损害的大鼠模型,探讨了汞中毒时血、肾和尿中碱性磷酸酶(ALP)活性的变化关系。结果表明,大鼠肾匀浆中 ALP活性明显低于对照组,尿 ALP活性则显著增加。ALP 活性降低的部位在肾近曲小管。体外实验未发现氯化汞对肾、尿ALP 具有直接抑制作用或激活作用。尿中ALP 活性的增高是汞引起的肾小管上皮细胞损伤所致。它可作为汞中毒肾损害的一个观察指标。  相似文献   
3.
We have established hybridoma lines which secrete mouse monoclonal antibodies (Mabs) to human pituitary growth hormone, hGH. Using indirect competitive ELISA and indirect passive hemagglutination inhibition twelve different Mabs were characterized with regard to cross-reactivity with the hGH-related hormones, human chorionic somatomammotropin, hCS, and human prolactin, hPRL. The reactivity of these Mabs with pituitary hGH was compared to that with either bacterially-produced methionyl-hGH or to that of reduced and S-carboxymethylated hGH, which has an altered conformation. None of the Mabs reacted with hPRL. Four did not react with hCS whereas the others showed varying degree of cross-reactivity with hCS. All Mabs reacted more weakly with reduced and S-carboxymethylated hGH than with the native form of the hormone, which was not seen with conventional rabbit antisera to hGH. Thus in the case of hGH the Mabs are superior to conventional antisera in revealing small conformational differences. However the pituitary and bacterially-derived methionyl-hGH were indistinguishable as determined by the 12 Mabs.  相似文献   
4.
目的:观察五倍子水提取物对内毒素(LPS)所致人牙周膜细胞(PDLC)活性降低、超微结构损伤、在牙骨质片表面附着减少、以及碱性磷酸酶(ALP)活性降低的影响,探讨五倍子水提取物对PDLC的保护作用.方法:采用细胞培养技术、3H-TdR掺入法、细胞计数法、透射与扫描电子显微镜技术、酶联免疫技术观察五倍子水提取物对PDLC的保护作用.结果:培养液中加入100μg/mL LPS时,PDLC活性和ALP活性受到明显抑制,超微结构损伤,细胞在牙骨质片表面附着减少.加入五倍子水提取物溶液后,对LPS抑制PDLC活性和ALP活性,以及超微结构损伤、牙骨质片表面附着减少有拮抗作用,该作用随五倍子水提取物浓度增加而增加,到10μg/mL时,达到峰值.结论:五倍子水提取物对PDLC具有保护作用,有望成为防治牙周病的药物.  相似文献   
5.
Octacalcium phosphate (OCP), a type of bioactive ceramics, may be associated with dentine, tooth apatite, and especially bone generation, and promotes wound healing after fracture. Recently, commercial bone grafting products containing a large amount of OCP material have been released because OCP can be synthesized in large quantities. It is reported to increase cell proliferation, but the interaction between OCP and cell signaling pathways is still unclear. In this study, first, we demonstrated OCP mediated cell signaling pathways with only purified OCP materials. OCP regulated P38, JNK (c-Jun N-terminal kinase), Src, and AKT (protein kinase B) signaling pathways. OCP crystals appeared in the characteristic ribbon shape but varied by several tens of micrometers in size. The X-ray diffraction pattern was the same as previously reported. We studied two concentrations of OCP (10 mg/ml and 20 mg/ml) to understand whether the effect of OCP on cell signaling pathways is dose dependent. We confirmed that OCP treatment affected cell proliferation and alkaline phosphatase and disrupted Src phosphorylation but did not change the total protein level. P38 phosphorylation was activated with OCP treatment and inhibited by SB203580, but P38 total protein level did not change. OCP inhibited JNK phosphorylation signaling, whereas PD98509 inhibited JNK phosphorylation with or without OCP. Interestingly, the AKT total level decreased after OCP treatment, but AKT phosphorylation increased considerably. Our results demonstrate that OCP materials modulate cell signaling pathways and increase cell proliferation.  相似文献   
6.
Caco-2细胞模型验证指标的选择与评判   总被引:4,自引:0,他引:4       下载免费PDF全文
 目的建立Caco-2细胞模型并探讨验证该模型指标的选择与评判。方法在所建立的Caco-2单层细胞模型上,通过测定跨上皮细胞膜电阻(TEER),比较膜两侧碱性磷酸酶(ALP)活性,计算几种公认的标记物在单层模型转运参数等对Caco-2细胞单层可靠性进行评价。结果TEER在细胞单层形成过程中稳定增长,膜两侧培养液中ALP活性差异逐步加大,细胞旁及跨细胞转运标记物均呈现可预见的低或高表观渗透系数(Papp)值,P-gp标准底物非索非那定双侧转运流出率(ER)大于2。结论建立的Caco-2细胞模型在完整性、细胞极性、通透性以及P-gp表达等方面均符合胃肠吸收化合物机制研究的要求。  相似文献   
7.

Ethnopharmacological relevance

Velvet antlers (VA) have been claimed for centuries to have numerous medical benefits including strengthen bones. To investigate and compare the anti-osteoporotic activities from different sections of VA.

Materials and methods

Fresh VA prepared from farmed sika deers (Cervus nippon) was divided into upper (VAU), middle (VAM), and basal (VAB) sections. The chemical constituents and anti-osteoporotic effect of different sections from VA were evaluated using ovariectomized rats.

Results

Levels of water-soluble extracts, diluted alcoholic extract, amino acids, testosterone, insulin-like growth factor (IGF)-1and testosterone plus estradiol significantly differed among the different sections. Levels of these constituents were significantly higher in the upper section than in the basal section. Moreover, levels of testosterone and IGF-1 of the VAM were also significantly higher than those of the VAB. Calcium level increased downward from the tip with statistical significance. The strength of vertebrae increased in all VA-treated groups compared to the control, but only treatment with VAU and VAM increased the strength of the femur and the microarchitecure of the trabecular bone. Alkaline phosphatase levels of VAU- and VAM-treated groups significantly decreased, but osteocalcin did not significantly change. Moreover, VAU and VAM dose-dependently increased proliferation and mineralization of MC3T3-E1 cells.

Conclusion

Our study provides strong evidence for the regional differences in the effectiveness of velvet antler in treating osteoporosis. However, further studies are needed to elucidate the bioactive chemical constituents associated with the anti-osteoporotic effects of velvet antler.  相似文献   
8.

Ethnopharmacological relevance

Long-term excess alcohol exposure leads to alcoholic liver disease (ALD)—a global health problem without effective therapeutic approach. ALD is increasingly considered as a complex and multifaceted pathological process, involving oxidative stress, inflammation and excessive fatty acid synthesis. Over the past decade, herbal medicines have attracted much attention as potential therapeutic agents in the prevention and treatment of ALD, due to their multiple targets and less toxic side effects. Several herbs, such as Cnidium monnieri (L.) Cusson (Apiaceae), Curcuma longa L. (Zingiberaceae) and Pueraria lobata (Willd.) Ohwi (Leguminosae), etc., have been shown to be quite effective and are being widely used in China today for the treatment of ALD when used alone or in combination.

Aim of the review

To review current available knowledge on herbal medicines used to prevent or treat ALD and their underlying mechanisms.

Materials and methods

We used the pre-set searching syntax and inclusion criteria to retrieve available published literature from PUBMED and Web of Science databases, all herbal medicines and their active compounds tested on ALD induced by both acute and chronic alcohol ingestion were included.

Results

A total of 40 experimental studies involving 34 herbal medicines and (or) active compounds were retrieved and reviewed. We found that all reported extracts and individual compounds from herbal medicines/natural plants could be beneficial to ALD, which might be attributed to regulate multiple critical targets involved in the pathways of oxidation, inflammation and lipid metabolism.

Conclusions

Screening chemical candidate from herbal medicine might be a promising approach to drug discovery for the prevention or treatment of ALD. However, further studies remain to be done on the systematic assessment of herbal medicines against ALD and the underlying mechanisms, as well as their quality control studies.  相似文献   
9.
The present study was designed to investigate whether Erythrina variegata L. (EV), which belongs to the leguminous family, exerted any beneficial effects on bone in ovariectomized rats. Daily oral administration of the EV extract at 300 and 600 mg/kg for 14 weeks to rats prevented the OVX-induced increase in the serum OCN, ALP, and urinary DPD levels. Histomorphometric analysis of the proximal end of the tibia showed that the EV extract prevented the estrogen deficiency-induced decrease in trabecular thickness and trabecular area, as well as restoring the increase in trabecular separation in a dose-dependent manner. Moreover, the EV extract improved the energy absorption and stiffness of the mid-shaft of the rat femur. Thus, the present study clearly demonstrated that EV could suppress the high rate of bone turnover induced by estrogen deficiency, inhibit bone loss and improve the biomechanical properties of bone in the OVX rats.  相似文献   
10.
李翠萍  黄霞  李焱  朱颖飞 《河南中医》2007,27(12):25-27
目的:探讨更年乐水丸治疗摘除卵巢所致雌性大鼠骨质疏松的作用机理。方法:选用55只3月龄SD雌性大鼠随机分为假手术组、模型对照组、阳性对照组、更年乐水丸低剂量组、更年乐水丸高剂量组。后4组摘除双侧卵巢,于造模后第2天开始中药灌胃,连续45 d,处死动物后,取动物左侧股骨,测定骨密度;测定血清E2、PTH、IL-6、Alp、Acp的水平。结果:更年乐水丸能增加大鼠骨密度及提高血清E2水平,降低Alp、Acp、PTH、IL-6含量。结论:更年乐水丸可改变绝经后早期骨代谢高转换状态。  相似文献   
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