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1.
张旭东  郭树忠 《医学争鸣》2005,26(18):1716-1718
CTLA4-Ig是一种融合免疫球蛋白,可以选择性地阻断CD28与B7的信号传导通路,导致T细胞免疫失能,诱导对特异性抗原的免疫耐受. 本文介绍了其生物学特性、免疫诱导耐受机制及在异体移植方面的研究进展和局限性,其在异体移植方面展示了良好的应用前景.  相似文献   
2.
A 73-year-old woman was studied after admission for anteriorwall ST-segment elevation myocardial infarction. Transthoracicechocardiography (GE Vingmed, Vivid 7, Horten, Norway)  相似文献   
3.
反相高效液相色谱法测定牛黄类中成药中胆汁酸的含量   总被引:7,自引:0,他引:7  
倪坤仪  王建  陈健  郁建  屠树滋 《药学学报》1994,29(8):624-633
反相高效液相色谱法测定牛黄类中成药中胆汁酸的含量倪坤仪,王建,陈健,郁建,屠树滋(中国药科大学210009)含牛黄的中成药种类很多,在医疗中具有广泛的用途。中药牛黄中主要成分为胆汁酸和胆红素。本文主要研究用HPLC法测定牛黄以及含牛黄中成药中胆汁酸的...  相似文献   
4.
新生儿和儿童乙肝免疫   总被引:3,自引:1,他引:2  
自1991年WHO提出将乙型肝炎病毒(HBV)疫苗纳入新生儿计划免疫以来,绝大多数国家新生儿HBV疫苗接种覆盖率平均在90%以上,婴儿HBV疫苗接种覆盖率为85%-99%.我国HBsAg携带率从10.19%下降到0.2%-3.2%.不同地区新生儿和儿童全程接种率、首针及时接种率、免疫覆盖率差异较大.对不同新生儿和儿童HB免疫尚需注意的问题如HBV疫苗接种程序和接种剂量,早产、低体质量儿的免疫接种,HBsAg阳性母亲子女的免疫接种和母乳喂养,抗-HBs保护时间和加强免疫问题.  相似文献   
5.
INTRODUCTION: Broncholithiasis is often seen after chronic granulomatous diseases such as tuberculosis and hystoplasmosis and leads to a wide spectrum of signs and symptoms; including hemoptysis which often needs surgical management. The goal of this study is evaluation of surgery in patients with tuberculous broncholithiasis who present with hemoptysis. MATERIALS AND METHODS: In this study all patients with tuberculous broncholithiasis had been operated on between 1991 and 2005, followed up at least 6 months and at most 9 years, and studied relating to age, sex, clinical symptoms, diagnostic methods, type of surgical treatment, complications and mortality. RESULTS: Overall 5 patients have been studied (male:female=2:3, mean=31 years); 2 with severe and 3 mild to moderate and recurring hemoptysis, lesion at left in 80% and at right in 1, in 3 patients some degree of bronchiectasia was seen, in 4 the lesion was visible in bronchoscopy and endoscopic removal of the lesion failed in all. Three of patients underwent pulmonary resections and in 2 broncholithotomy has been done. In follow-up, patients treated with pulmonary resection have had no subsequent problems, but in patients treated with broncholithotomy due to occurring late bronchiectasia, re-operation and pulmonary resection was inavoidable. There was no mortality. CONCLUSION: Regarding the dangers of hemoptysis and excellent results of surgery and possible occurance of late bronchiectasia after broncholithotomy, the results of our study show that pulmonary resection distal to the lesion and as the retention of lung of parenchyma is preferable. Broncholithotomy should be done only in patients in whom pulmonary resection is not technically possible. Because of the very low occurance of this complication complete studies are needed.  相似文献   
6.
Lipoteichoic acids (LTA), cell wall components of gram-positive bacteria, have been reported to induce various inflammatory mediators and to play a key role in gram-positive-microbe-mediated septic shock. In a large number of these studies, investigators used commercially available LTA purified from a variety of gram-positive bacteria, including Staphylococcus aureus, Bacillus subtilis, and Streptococcus sanguis. We report here that, although these commercially available LTA could be readily shown to stimulate production of nitric oxide (NO) in RAW 264.7 mouse macrophages, the activity was dramatically inhibited by polymyxin B, a relatively specific inhibitor of endotoxin biological activity. One-step purification of the commercially available S. aureus LTA using hydrophobic interaction chromatography resulted in two well-separated peak fractions, one highly enriched for LTA and a second highly enriched for endotoxin. The LTA-enriched fractions did not induce production of NO in RAW 264.7 macrophages, although they caused a dose-dependent induction of NO in the presence of low concentrations of gamma interferon (IFN-gamma) (which by itself induced little NO), regardless of the presence of polymyxin B. In contrast, the endotoxin-enriched fractions by themselves inhibited in high levels of NO in RAW 264.7 macrophages but activity was almost completely inhibited in the presence of polymyxin B. Consistent with these findings, our data also indicate that commercial LTA preparations from S. aureus, B. subtilis, and S. sanguis were not able to induce NO from lipopolysaccharide-hyporesponsive C3H/HeJ mouse peritoneal macrophages, but in the presence of IFN-gamma, these LTA preparations were able to induce relatively high levels of NO from C3H/HeJ macrophages. These results indicate that commercially available LTA can contain contaminating and potentially significant levels of endotoxin that can be expected to contribute to the putative macrophage-stimulating effects of LTA as assessed by NO production. The fact that the purified LTA, by itself, was not able to induce significant levels of NO secretion in RAW 264.7 macrophages supports the conclusion that caution in attributing high-level biological activity to this microbial cell wall constituent should be exercised.  相似文献   
7.
Summary The venous architecture in donor flaps was observed in 17 fresh cadavers by injection of latex or ink into the vessels or by making corrosion-cast specimens. The pattern of the veins resembles that of the arteries, with the difference that there is another set of venous trunks which do not accompany the arteries. Because these trunks are of larger caliber, they are the main drainage route for flaps. There are three types of drainage based on the anatomical architecture: 1) the superficial trunk is the main drainage path; 2) the deep trunk is the main path; 3) both superficial and deep veins are involved. These morphological considerations are the basis for selection of veins for anastomosis in microsurgery. The axial veins in temporal, frontal and facial flaps on the dorsum of the hand and the foot usually loosely accompany the axial arteries. The characteristics of these vascular pedicules should be studied in transplant operation.
Bases anatomiques du drainage veineux des lambeaux cutanés libres
Résumé Le drainage veineux des lambeaux cutanés libres a été étudié sur 17 cadavres frais par injection de latex ou d'encre dans les vaisseaux, ou en réalisant des moulages par injection-corrosion. La distribution des veines ressemble à celle des artères à la différence près qu'il existe des troncs veineux qui n'accompagnent pas les artères. Ces troncs ont un calibre plus important et représentent une voie de drainage principale pour les lambeaux. On peut individualiser trois types de drainages basés sur l'architecture veineuse : 1. Le tronc superficiel est la principale voie de drainage ; 2. le tronc profond est la principale voie; 3. les veines superficielles et profondes sont impliquées simultanément. Ces considérations morphologiques sont les bases de la sélection des axes veineux pour les anastomoses en micro-chirurgie. Les veines axiales au niveau temporal, frontal et facial et pour les lambeaux de la face dorsale de la main et du pied sont habituellement relativement éloignées du trajet artériel. Les caractéristiques de ces pédicules veineux doivent être précisées pour la réalisation des lambeaux.
  相似文献   
8.
9.
Solitary fibrous tumours are infrequent neoplasms based in the pleura that are predominantly benign with malignant pathology and behaviour described in 10–36% of cases. Extrathoracic solitary fibrous tumours (ESFTs) have been considered separately to their intrathoracic counterparts and comprise a third of all solitary fibrous tumours. The extrathoracic location was identified as an adverse prognostic factor for local recurrence but not for metastatic disease. So far, there have not been any reports of solitary fibrous tumours demonstrating caval infiltration. We present a case of a benign ESFT infiltrating into the perirenal inferior vena cava. Together with extrauterine leiomyomas, ESFTs should also be considered as a differential diagnosis for the rare benign lesions invading the inferior vena cava.  相似文献   
10.
Due to the extreme pore volume and valuable surface area, zeolitic imidazole frameworks (ZIFs) are promising vehicles that enhance the delivery of therapeutic agents to tissues. Furthermore, these nanoporous materials have high stability in the pH and temperature of the surrounding healthy cells (37 °C and pH = 7) and an exotic potential to deform in carcinogenic environment (T > 37 °C and pH ∼ 5.5), which make them perfect smart drug delivery vehicle candidates. In this work, a series of molecular dynamics (MD) and metadynamics simulations have been performed to gain molecular insight into the mechanisms involved in the process of co-loading of doxorubicin (DOX) and EpiGalloCatechin-3 Gallate (EGCG) on ZIF-8, which form a smart drug delivery system (SDDS). The obtained results revealed that DOX was adsorbed on the carrier mostly through electrostatic interactions (Ecoul = ∼−1200 kJ mol−1, Etot = −1700 kJ mol−1), and EGCG was stacked on ZIF-8 mainly via van der Waals interactions (EL-J = ∼−600 kJ mol−1, Etot = ∼−1200 kJ mol−1). It is worth mentioning that the drug–drug L-J interactions (EL-J = ∼500 kJ mol−1) were also important in the co-loading process. The insertion of DOX and EGCG as additive agents to the initial ZIF-8/EGCG and ZIF-8/DOX systems led to the enhancement of the drug–carrier pair interactions to about ∼−2300 kJ mol−1 and ∼−2000 kJ mol−1, respectively. This finding implied that the drug–drug interactions had a complementary role in the development of SDDS via ZIF-8. From the metadynamics simulation, it was found that the geometry of the drugs is a determining factor in an efficient co-loading SDDS.

Adsorption free energy of a molecule depends on where and how the molecule meets ZIF-8 surface.  相似文献   
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