全文获取类型
收费全文 | 11328篇 |
免费 | 672篇 |
国内免费 | 84篇 |
专业分类
耳鼻咽喉 | 293篇 |
儿科学 | 365篇 |
妇产科学 | 258篇 |
基础医学 | 1475篇 |
口腔科学 | 363篇 |
临床医学 | 876篇 |
内科学 | 2207篇 |
皮肤病学 | 377篇 |
神经病学 | 749篇 |
特种医学 | 730篇 |
外科学 | 1807篇 |
综合类 | 56篇 |
预防医学 | 674篇 |
眼科学 | 308篇 |
药学 | 691篇 |
中国医学 | 72篇 |
肿瘤学 | 783篇 |
出版年
2023年 | 115篇 |
2022年 | 195篇 |
2021年 | 387篇 |
2020年 | 258篇 |
2019年 | 345篇 |
2018年 | 399篇 |
2017年 | 347篇 |
2016年 | 493篇 |
2015年 | 524篇 |
2014年 | 524篇 |
2013年 | 639篇 |
2012年 | 799篇 |
2011年 | 666篇 |
2010年 | 519篇 |
2009年 | 363篇 |
2008年 | 533篇 |
2007年 | 484篇 |
2006年 | 478篇 |
2005年 | 440篇 |
2004年 | 399篇 |
2003年 | 308篇 |
2002年 | 284篇 |
2001年 | 211篇 |
2000年 | 200篇 |
1999年 | 217篇 |
1998年 | 132篇 |
1997年 | 103篇 |
1996年 | 73篇 |
1995年 | 46篇 |
1994年 | 52篇 |
1993年 | 57篇 |
1992年 | 57篇 |
1991年 | 72篇 |
1990年 | 47篇 |
1989年 | 66篇 |
1988年 | 58篇 |
1987年 | 49篇 |
1986年 | 45篇 |
1985年 | 42篇 |
1984年 | 35篇 |
1983年 | 39篇 |
1982年 | 38篇 |
1981年 | 45篇 |
1979年 | 40篇 |
1978年 | 34篇 |
1975年 | 37篇 |
1974年 | 35篇 |
1973年 | 35篇 |
1932年 | 35篇 |
1930年 | 31篇 |
排序方式: 共有10000条查询结果,搜索用时 24 毫秒
31.
K. Bonatz A. Weiss R. Hehlmann H. -P. Aßmus M. Heine 《Journal of molecular medicine (Berlin, Germany)》1991,69(18):853-856
Summary A 40-year-old, HIV-infected female patient received antibiotic treatment for a urinary tract infection. After the initial success of therapy and a symptom-free period, she developed pneumonia with septic shock and adult respiratory distress syndrome (ARDS). In spite of intensive care and respirator therapy with positive end-expiratory pressure (PEEP), she died of infectious toxic shock. Autopsy findings showed relapsing, gramnegative, bacterial pneumonia (morphologically compatible with Klebsiella pneumonia) and secondary, invasive aspergillosis. The pathogenesis and epidemiology of these unusual complications of AIDS are discussed.Abbreviations AIDS
acquired immunodeficiency syndrome
- ARDS
adult respiratory distress syndrome
- CDC
Centers for Disease Control
- HIV
human immunodeficiency virus
- PEEP
positive end-expiratory pressure 相似文献
32.
Z. Bircan M. Soran I. Yildirim M. Doĝan A. Şahin A. Bilici M. Danaci 《International urology and nephrology》1997,29(3):357-361
Radius, ulna, short bones (RUS), carpal (CARP) bone age (BA), tibial corticodiaphyseal (C/D) ratio and trabecular aspect were
assessed in 19 children with steroid dependent nephrotic syndrome and 15 age matched healthy children. Both RUS and CARP BA
were significantly lower than in the controls. Trabecular aspect and tibial C/D ratio did not show any statistical significance.
There was a positive correlation between HSDS and RUS BA delay (r=−0.476, p<0.05); CARP BA delay and RUS BA delay (r=0.563,
p<0.01) and RUS BA and CARP BA (r=0.891, p<0.001). In conclusion, RUS and CARP BA are both retarded and positively correlated
in steroid dependent nephrotic children. 相似文献
33.
Summary A rapid and quantitative method for the determination of benzodiazepines using high-performance liquid chromatography (HPLC)
with diode-array detection (DAD) is reported. The drugs were extracted from serum, blood or post-mortem blood using C18 extraction columns. Brotizolam was used as internal standard. Experiments with spiked serum/blood samples resulted in recoveries
between 75% and 94% for all investigated benzodiazepines. Excellent linearity was obtained over the concentration range 5–1500
ng benzodiazepine/ml. The limit of detection was approximately 2 ng/ml. The detection of low therapeutic serum levels of highly
potent benzodiazepines is also possible.
相似文献
34.
Hypoxic pulmonary vasoconstriction (HPV) was first described by von Euler and Liljestrand in 1946 and is still the only known vascular feedback control mechanism in the lung. This technique results in a redistribution of blood flow away from poorly ventilated areas into better ventilated regions, thus reducing shunt. HPV functions as a local mechanism that acts in response to alveolar hypoxia but in the smallest areas of the lung, making it an important mechanism in all situations where ventilation perfusion mismatch occurs. To be effective, HPV needs normal pulmonary areas into which blood flow can be diverted. This explains why the efficacy of the treatment depends on the area that is vasoconstricted. The effect on PaO2 is maximal when the amount of the hypoxic lung ist 30–70%. If the area in vasoconstriction is small, the influence on PaO2 is negligible. On the other hand, when most of the lung is hypoxic, there is no significant normoxic region to which the hypoxic region can divert flow. In that case it does not matter, in terms of PaO2, whether the hypoxic region has active hypoxic pulmonary vasoconstriction or not. In this situation HPV becomes a rather detrimental mechanism, because it causes an increase in pulmonary arterial pressure. At some stage a turning point, where the gain in PaO2 is lost due to an increase in right ventricular afterload, inducing a decrease in CO. The reaction is diminished by exogenous manipulations, drugs (inhalation anesthetics, direct vasodilators), endotoxin, very low PaO2 values, vasodilating mediators and changes in the acid-base balance. Acidosis and alcalosis inhibit HPV. Factors like spontaneous or mechanical ventilation, PEEP, open or closed chest, and the type of hypoxia (atelectasis or nitrogen) have no influence on HPV. The small arteries, those less than 500?μm in diameter, were identified as the location of the hypoxic constriction. Pulmonary vascular smooth muscle cells in pure culture undergo reversible and repeated hypoxic constriction. Examination of a histological lung section emphasizes that the small arteries are closely surrounded by alveoli gas on the outside and by mixed venous blood on the inside. Thus, the response is believed to be accounted for by each smooth muscle cell in the pulmonary arterial wall responding proportionally to the local oxygen tension in its vicinity and depending on alveolar as well as mixed venous oxygen pressure. The biochemical intracellular mechanism remains unknown. 相似文献
35.
Ahmet Terzioglu Ferruh Bingul Do?an Tuncali Firdevs Sahin Gürcan Aslan 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》2004,38(5):317-319
We describe a woman with osseous destruction and rupture of the extensor tendon as a result of sarcoidosis in the left third finger with no evidence of systemic involvement. The tendon was repaired and she was successfully treated with prednisone. 相似文献
36.
Zusammenfassung Medikamente – insbesondere solche mit zentralnervöser Wirkung – können einerseits die Fahrsicherheit einschränken, andererseits kann durch eine Arzneimitteltherapie eine krankheitsbedingt eingeschränkte Fahrsicherheit gebessert bzw. eine Fahreignung wiederhergestellt werden. Für die verschiedenen verkehrsmedizinisch bedeutsamen Arzneimittelgruppen werden im Folgenden die relevanten Leistungseinbußen dargestellt. Die dem Arzt im Zusammenhang mit einer Arzneimitteltherapie obliegenden umfangreichen Beratungs- und Hinweispflichten für seinen Patienten werden ebenfalls vorgestellt. 相似文献
37.
38.
K. Q. Do P. L. Herrling P. Streit M. Cuénod 《Journal of neural transmission (Vienna, Austria : 1996)》1988,72(3):185-190
Summary Sulfur containing amino acids such as homocysteic acid (HCA), cysteinsulfinic acid, homocysteinsulfinic acid are released by depolarization of slices from various rat brain regions in a Ca++-dependent manner. L-HCA excites caudate neurons through their N-methyl-D-aspartic acid (NMDA) receptor and potentiates their cortically evoked excitatory postsynaptic potentials.35S-methionine can label the releasable pool of HCA, and thus appears as a precursor of HCA. Thus HCA is a transmitter candidate which acts predominantly on the NMDA receptor. 相似文献
39.
S. Doğru-Abbasoğlu G. Aykaç-Toker H. A. Hanagasi H. Gürvit M. Emre M. Uysal 《Neurological sciences》2007,28(1):31-34
Abstract Alzheimer's disease (AD) is defined pathologically by the presence of β-amyloid plaques, neurofibrillary tangles and extensive
neuronal loss. Evidence indicates that increased DNA damage may contribute to neuronal loss in AD. Recently, it has been shown
that in AD neurons have a reduced capacity for some types of DNA repair. Polymorphisms in DNA repair genes may be associated
with differences in repair efficiency of DNA damage. Variants of several DNA repair genes, including the base excision repair
gene XRCC1, have been described previously. We hypothesised that Arg194Trp polymorphism of XRCC1 gene may contribute to genetic susceptibility for AD. In order to test this hypothesis, we investigated
Arg194Trp polymorphism at the XRCC1 gene in the DNA samples of 98 patients with AD and 95 healthy subjects. The frequency of the Trp allele was more pronounced among cases (11.2%) compared with controls (5.8%). On combining the homozygous and heterozygous
variants of each codon, the variants seemed to be at twofold risk of AD, although the risk estimates were not statistically
significant (OR=1.95, 95% CI 0.88–4.34, p=0.09). In addition, the 194Trp allele revealed a borderline significance (OR=2.05, 95% CI 0.96–4.37, p=0.056). According to our results, it may be speculated that the polymorphic variants of XRCC1 codon 194 have a role in the
development of AD. 相似文献
40.
Prof. Dr. D. Karch G. Groß-Selbeck J. Pietz H.-G. Schlack 《Monatsschrift für Kinderheilkunde》2005,153(8):782-785
The goal of Castillo-Morales’ orofacial therapy is to improve the coordination of oral motor functions in cooperation with other body systems. The processes involved in sucking, biting, chewing and swallowing are stimulated by specific techniques of sensory stimulation such as touching, stroking, stretching, exerting pressure or the vibration of mimic and tongue-bone musculature, as well as massage of the gums and palate or the application of technical apparatus. Sufficient head and posture control is fundamental and must be the first goal. Successful therapy, especially for ICP-children, has been documented in progress reports and case studies. As yet, however, there is no evidence of specific effects on eating and speech functions. Therefore, the therapy can be recommended only in order to achieve specific goals and for a limited time, being aware of the risk of overstimulation. 相似文献