全文获取类型
收费全文 | 249篇 |
免费 | 2篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 4篇 |
妇产科学 | 32篇 |
基础医学 | 70篇 |
临床医学 | 20篇 |
内科学 | 34篇 |
神经病学 | 25篇 |
特种医学 | 1篇 |
外科学 | 17篇 |
综合类 | 7篇 |
预防医学 | 11篇 |
眼科学 | 1篇 |
药学 | 23篇 |
中国医学 | 1篇 |
肿瘤学 | 4篇 |
出版年
2021年 | 3篇 |
2020年 | 3篇 |
2018年 | 2篇 |
2017年 | 5篇 |
2016年 | 6篇 |
2015年 | 3篇 |
2014年 | 3篇 |
2013年 | 10篇 |
2012年 | 6篇 |
2011年 | 3篇 |
2009年 | 6篇 |
2008年 | 8篇 |
2007年 | 7篇 |
2006年 | 12篇 |
2005年 | 9篇 |
2004年 | 12篇 |
2003年 | 4篇 |
2002年 | 12篇 |
2000年 | 2篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1994年 | 2篇 |
1991年 | 3篇 |
1985年 | 2篇 |
1981年 | 2篇 |
1979年 | 2篇 |
1977年 | 2篇 |
1973年 | 4篇 |
1972年 | 5篇 |
1967年 | 2篇 |
1966年 | 4篇 |
1962年 | 2篇 |
1960年 | 2篇 |
1955年 | 2篇 |
1944年 | 2篇 |
1942年 | 4篇 |
1941年 | 2篇 |
1939年 | 4篇 |
1937年 | 2篇 |
1936年 | 2篇 |
1933年 | 4篇 |
1932年 | 2篇 |
1930年 | 2篇 |
1929年 | 5篇 |
1927年 | 5篇 |
1926年 | 5篇 |
1925年 | 6篇 |
1924年 | 2篇 |
1923年 | 9篇 |
1922年 | 7篇 |
排序方式: 共有251条查询结果,搜索用时 15 毫秒
1.
Monoclonal antibodies (Mabs) defining 14 distinct polymorphic epitopes have been produced against the class II antigens of HLA-DR3Dw3DQw2 cells. Population analysis indicates that Mab C1 is directed against the DQw2 specificity and Mab M6 against the DRw52 specificity. The remaining Mabs define epitopes shared by the class II molecules of DR3 and various other specificities. Seven DR3Dw3DQw2 haplotypes were examined and could be divided into two types based on the presence of the epitope defined by Mab M3. Analysis of DR2 and DR4 homozygous cells with these Mabs revealed several distinct patterns of epitope expression. These subdivisions were found to correlate with the cellularly defined Dw specificities. 相似文献
2.
Dipl.-Ing. Hellmuth Bayha 《Medical microbiology and immunology》1952,135(1):1-26
Ohne ZusammenfassungGekürzte Wiedergabe einer von der Fakultät für Maschinenwesen der Technischen Hochschule Karlsruhe genehmigten Dissertation.Die Arbeiten wurden durchgeführt im Tuberkulose-Forschungsinstitut Borstel (Direktor: Professor Dr. Dr. E.Freerksen).Dem Tuberkulose-Forschungsinstitut Borstel und seinem Direktor, Herrn Professor Dr. Dr. E.Freerksen, danke ich bestens, daß mir die Möglichkeit gegeben wurde, in Borstel die umfangreichen experimentellen Untersuchungen durchzuführen, die die Grundlage dieser Arbeit bilden. Ebenso danke ich den Siemens-Schuckertwerken, Erlangen, die die Arbeit dadurch förderten, daß sie Versuchsgeräte und Meßinstrumente zur Verfügung stellten.Schließlich danke ich den Herren Professor Dr. phil. P.Schulz und Professor Dr.-Ing. J.Kuprianoff, Karlsruhe, für die große Unterstützung, die sie mir als Referent bzw. Korreferent bei dem Promotionsverfahren gewährten. 相似文献
3.
Polymere ammoniumsalze aus N,N,N′,N′-tetramethylalkylendiaminen und N,N′-alkylenbis(chloracetamid)en
Long chain polymeric ammonium salts 3a–g and 4a were prepared in DMF/H2O from N,N,N′,N′-tetramethylalkylenediamines 2a and 2b and N,N′-alkylenebis(chlorocetamide)s 1a–g . Some of them can be casted to clear transparent sheets. The chlorine atoms in 1a – g are activated by the adjacent carbonyl amino group. The polymer from N,N′-tetramethylenebis(chloroacetamide) ( 1d ) and N,N,N′,N′-tetramethylhexamethylenediamine (2b) shows an intrinsic viscosity of 61 ml/g, the highest value known for polyelectrolytes so far. The intrinsic viscosity decreases with increasing numbers of CH2-groups in the monomers. The polymeric ammonium salts 3a – g and 4a give sheets from DMF solutions, which are soluble in water and stable under normal conditions. Polymers which are best suitable for the preparation of sheets show less hygroscopicity than the others, due to their structure. Intrinsic viscosities were calculated from the reduced specific viscosities measured in 0,4 M KCl but may be also determined in water by the method of Yuan et al., plotting the reduced specific viscosities as a function of 1/√c. 相似文献
4.
Mackert BM Wübbeler G Leistner S Uludag K Obrig H Villringer A Trahms L Curio G 《Neuroreport》2004,15(1):63-66
Most functional brain imaging methods detect neuronal activations indirectly through the accompanying neurovascular response. Here, we demonstrate that a novel methodological approach, the combination of DC-magnetoencephalography (DC-MEG) and near-infrared spectroscopy (NIRS), allows non-invasive assessment of the dynamics of neurovascular coupling in the human brain: detecting directly slow neuronal processes (with time constants of 30s), DC-MEG revealed, even in unaveraged recordings, sustained neuronal activations at pericentral hand cortices contralateral to repetitive finger movements; these were accompanied by the ensuing local vascular response showing similar dynamical features as quantified by simultaneously recorded NIRS. This non-invasive approach opens a new avenue for the understanding of neurovascular coupling during physiological tasks as well as in diseases involving slow neuronal depolarization shifts and alterations of blood flow, such as stroke or migraine. 相似文献
5.
Dayen C Mishellany H Hellmuth D Mayeux I Aubry P Glerant JC Auquier MA Reix T Abet D Jounieaux V 《Revue des maladies respiratoires》2001,18(5):537-540
A triad of signs constitutes Boerhaave syndrome: forceful vomiting, chest pain and subcutaneous emphysema. The syndrome results from spontaneous rupture of the oesophageal wall leading to an oeso-pleural or oeso-mediastinal fistula. Positive diagnosis is established with a water-soluble swallow, sometimes coupled with computed tomography of the thorax. Boerhaave syndrome is a surgical emergency. We report three cases of spontaneous rupture of the oesophagus and analyze the importance of emergency surgery as well as emergency treatment of the sepsis, an important prognosis factor. 相似文献
6.
7.
Julius Eduard Hellmuth Arina Corli Hitzeroth Robert Richard Bragg 《Avian pathology》2017,46(3):272-277
Infectious coryza, an upper respiratory tract disease in chickens, caused by Avibacterium paragallinarum, leads to huge economic losses. The disease is controlled through vaccination; but vaccination efficacy is dependent on correct identification of the infecting serovar, as limited cross-protection is reported amongst some serovars. Current identification methods include the heamagglutination inhibition test, which is demanding and could be subjective. To overcome this, molecular typing methods proposed are the Multiplex polymerase chain reaction (PCR) and Restriction Fragment Length Polymorphism-PCR, but low reproducibility is reported. Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR has been suggested for molecular groupings of various bacterial species. This study focuses on evaluating the ERIC-PCR as a probable method to differentiate between different Av. paragallinarum serovars by grouping with reference isolates, based on clonal relations. The ERIC-PCR was performed on 12 reference isolates and 41 field isolates originating from South Africa and South America. The data indicate that the ERIC-PCR is not ideal for the differentiation or for molecular typing of Av. paragallinarum serovars, as no correlation is drawn upon comparison of banding patterns of field isolates and reference strains. However, the results do indicate isolates from the same origin sharing unique banding patterns, indicating potential clonal relationship; but when compared to the reference isolates dominant in the specific area, no correlation could be drawn. Furthermore, although the ERIC-PCR serves a purpose in epidemiological studies, it has proved to have little application in differentiating amongst serovars of Av. paragallinarum and to group untyped field strains with known reference strains. 相似文献
8.
9.
Frank Girardi M.D. Michaela Heydarfadai M.D. Franz Koroschetz M.D. Hellmuth Pickel M.D. Raimund Winter M.D. 《Gynecologic oncology》1994,55(3)
Ninety patients with cervical intraepithelial neoplasia (CIN) were randomly assigned to loop excision (n = 38) or cold-knife conization (n = 52). All specimens were well evaluable at histology. The average width of the lesions at histology was 10.2 and 9.7 mm, respectively (ns). The average weight of the specimens was 2.6 and 5.6 g (P < 0.01) and the average depth was 9.2 and 15.8 mm (P < 0.01), respectively. The distance between the cervical resection margin and CIN was 14 mm after loop excision and 24 mm after cold-knife conizatiun (P < 0.06). The margins of the specimen were not clear of disease in 8 patients after loop excision and in 12 patients after conization (ns). Two patients after loop excision and in three patients after cold-knife conization had postoperative bleeding. The results suggest that, compared with cold-knife conization, loop excision removes less healthy tissue without reducing the chances for cure. 相似文献
10.
Synthesis and Alkylation of 10H-Pyrimido[5,4-b][1,4]benzothiazines 10H-Pyrimido[5,4-b][1,4]benzothiazines 8 were prepared by condensation of barbituric acids 5 with 2-aminothiophenol (7) in DMSO via the ylide 6 . Compound 8 was characterized as a 1,5-dihydro system similar to the thia-isoalloxazines 1b . The structures of the alkyl derivatives isolated from a complex mixture were established by UV/VIS, 1H-NMR, IR and ESR spectroscopy. They are discussed with regard to the alkylation of pyrimidobenzothiazines which carry substituents at N-10. 相似文献