全文获取类型
收费全文 | 29455篇 |
免费 | 2116篇 |
国内免费 | 219篇 |
专业分类
耳鼻咽喉 | 71篇 |
儿科学 | 521篇 |
妇产科学 | 387篇 |
基础医学 | 10439篇 |
口腔科学 | 692篇 |
临床医学 | 3221篇 |
内科学 | 5260篇 |
皮肤病学 | 388篇 |
神经病学 | 820篇 |
特种医学 | 513篇 |
外国民族医学 | 3篇 |
外科学 | 1611篇 |
综合类 | 628篇 |
现状与发展 | 5篇 |
预防医学 | 3557篇 |
眼科学 | 253篇 |
药学 | 1934篇 |
1篇 | |
中国医学 | 223篇 |
肿瘤学 | 1263篇 |
出版年
2023年 | 1129篇 |
2022年 | 1146篇 |
2021年 | 1412篇 |
2020年 | 1774篇 |
2019年 | 1110篇 |
2018年 | 1083篇 |
2017年 | 1217篇 |
2016年 | 1301篇 |
2015年 | 1637篇 |
2014年 | 2344篇 |
2013年 | 1900篇 |
2012年 | 1492篇 |
2011年 | 1380篇 |
2010年 | 1731篇 |
2009年 | 1557篇 |
2008年 | 850篇 |
2007年 | 846篇 |
2006年 | 701篇 |
2005年 | 603篇 |
2004年 | 526篇 |
2003年 | 472篇 |
2002年 | 490篇 |
2001年 | 458篇 |
2000年 | 402篇 |
1999年 | 423篇 |
1998年 | 496篇 |
1997年 | 330篇 |
1996年 | 400篇 |
1995年 | 144篇 |
1994年 | 146篇 |
1993年 | 99篇 |
1992年 | 154篇 |
1991年 | 147篇 |
1990年 | 128篇 |
1989年 | 138篇 |
1988年 | 125篇 |
1987年 | 98篇 |
1986年 | 81篇 |
1985年 | 120篇 |
1984年 | 149篇 |
1983年 | 110篇 |
1982年 | 100篇 |
1981年 | 84篇 |
1980年 | 73篇 |
1979年 | 80篇 |
1977年 | 63篇 |
1976年 | 67篇 |
1974年 | 62篇 |
1973年 | 71篇 |
1972年 | 60篇 |
排序方式: 共有10000条查询结果,搜索用时 218 毫秒
1.
2.
In forensic medicine, although various alcohols have been reported as indicators of decomposition in collected blood, no studies have examined short-chain fatty acids as indicators. In this study, the blood n-butyric acid concentration was quantified, and the association between n-butyric acid and decomposition was investigated to determine whether the detection of n-butyric acid could be a new indicator of decomposition. Among the forensic autopsies performed from 2016 to 2018 in our laboratory, the cases were divided into decomposed (n = 20) and non-decomposed (n = 20) groups based on macroscopic findings. Blood samples collected at the time of autopsy were derivatized with 3-nitrophenylhydrazine hydrochloride after solid-phase extraction. The n-butyric acid concentration was measured using liquid chromatography–tandem mass spectrometry. In addition, ethanol and n-propanol were measured using a gas chromatography-flame ionization detector. There was a significant difference (p < 0.01) in the concentrations of n-butyric acid between the decomposed and non-decomposed groups (0.343 ± 0.259 [0.030–0.973] and 0.003 ± 0.002 [0.001–0.007] mg/mL, respectively). In the decomposed group, n-butyric acid was detected at high concentrations, even in cases where n-propanol was low. These results suggest that n-butyric acid is more likely to be an indicator of blood decomposition than n-propanol. 相似文献
3.
《Autoimmunity reviews》2022,21(9):103143
Autoimmune diseases (AID) are increasingly prevalent conditions which comprise more than 100 distinct clinical entities that are responsible for a great disease burden worldwide. The early recognition of these diseases is key for preventing their complications and for tailoring proper management. In most cases, autoantibodies, regardless of their potential pathogenetic role, can be detected in the serum of patients with AID, helping clinicians in making a definitive diagnosis and allowing screening strategies for early -and sometimes pre-clinical- diagnosis. Despite their undoubted crucial role, in a minority of cases, patients with AID may not show any autoantibody, a condition that is referred to as seronegative AID. Suboptimal accuracy of the available laboratory tests, antibody absorption, immunosuppressive therapy, immunodeficiencies, antigen exhaustion, and immunosenescence are the main possible determinants of seronegative AID. Indeed, in seronegative AID, the diagnosis is more challenging and must rely on clinical features and on other available tests, often including histopathological evaluation and radiological diagnostic tests. In this review, we critically dissect, in a narrative fashion, the possible causes of seronegativity, as well as the diagnostic and management implications, in several AID including autoimmune gastritis, celiac disease, autoimmune liver disease, rheumatoid arthritis, autoimmune encephalitis, myasthenia gravis, Sjögren’s syndrome, antiphospholipid syndrome, and autoimmune thyroid diseases. 相似文献
4.
《Autoimmunity reviews》2022,21(8):103137
BackgroundSjögren's syndrome (SjS) is a systemic autoimmune disease characterized by lymphocytic infiltration of the salivary and lacrimal glands associated with sicca syndrome. TAFRO syndrome is a systemic inflammatory disease of unknown cause, characterized by Thrombocytopenia, Anasarca, Fever, Reticulin fibrosis, Renal dysfunction and Organomegaly, first reported in 2010 in Japanese patients. Despite their rarity, both conditions have been concurrently reported in several patients during the recent years, hence questioning the existence of shared or related features.MethodsA systematic review of the literature regarding SjS associated with TAFRO syndrome (SjS-TAFRO) was performed. The 2019 updated Masaki diagnostic criteria were used for TAFRO syndrome and SjS was considered when the diagnosis was mentioned by the authors, necessarily with either anti-Sjogren's Syndrome A (SSA) ± anti-Sjogren's Syndrome B (SSB) antibodies and/or histological evidence of focal lymphocytic sialadenitis.ResultsTen cases of SjS-TAFRO have been reported in the literature to date. Compared to SjS patients without TAFRO syndrome, these 10 SjS-TAFRO had a lower female predominance (2.3:1 vs 9:1 women to man ratio) and a higher frequency of anti-SSA antibodies (90% vs 70%). All fulfilled the three major Masaki criteria i.e., anasarca, thrombocytopenia, and systemic inflammation. Seven of them (70%) had megakaryocyte hyperplasia or reticulin fibrosis in the bone marrow. Lymph node biopsy was performed in 8 out of 10 cases (80%) and results were consistent with Castleman disease in 6 (75%). Eight of them had developed renal failure (80%) within six months. Nine of them (90%) had organomegaly, with hepatosplenomegaly in 8 cases and splenomegaly alone in 1.ConclusionThis review brings new insights regarding TAFRO syndrome and suggests it could be a severe manifestation of SjS. The identification of shared abnormal signaling pathways could help in the therapeutic management of both diseases, which face an unmet therapeutic need. 相似文献
5.
《Clinical Microbiology Newsletter》2022,44(10):91-97
The analytic process for identification of anaerobic bacteria involves direct specimen Gram stains and workup of growth in culture. Direct Gram stains help to develop the initial differential, aiding in guiding both the extent of laboratory workup and clinician decision making for patient management. Workup of anaerobic growth should involve an aerotolerance test to assess aerobic growth and to compare growth rates in anaerobic versus aerobic environments. While matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) has become a routine means of anaerobe identification for many clinical laboratories, spot biochemical tests, such as indole and catalase, should be available in every laboratory that identifies anaerobes. If MALDI-TOF MS and biochemical methods are unsuccessful at providing an identification, 16S rRNA gene PCR and/or sequencing may be performed if the information impacts clinical care. The extent of culture workup to the level of presumptive identification versus definitive identification depends upon several factors, including the specimen source, direct Gram stain results, and the presence or absence of mixed microbiota. In addition to discussing the current best practices for anaerobic culture workup, commonly encountered anaerobic organism Gram stains and culture growth are detailed. 相似文献
6.
Apoorva Challa Neeraj Mahajan Seema Sood Arti Kapil Bimal Kumar Das Vishnubhatla Sreenivas Somesh Gupta 《Indian journal of medical microbiology》2022,40(3):433-435
Treatment guidelines for management of uncomplicated gonorrhoeae have been recently modified owing to alarming upsurge in azithromycin resistance. This study investigated the prevalence and genetic determinants of gonococcal azithromycin resistance in India. Four (5.7%) of 70 gonococcal isolates were resistant to azithromycin. Of 16 isolates investigated for molecular mechanisms of resistance, 13 (81.3%) and 6 (37.5%) isolates exhibited mutations in coding and promoter regions of mtrR gene, respectively. However, ermA, ermB and ermC genes or mutations in rrl gene were absent in all isolates. Azithromycin resistance is low in India posing no immediate threat to use of dual-therapy for syndromic management. 相似文献
7.
8.
9.
《Ticks and Tick》2022,13(3):101934
Anaplasmosis is a tick-transmitted disease due to several species of the genus Anaplasma. In 2019, we demonstrated the presence of Anaplasma capra in two deer species at a zoological park in mainland France. As we suspected its presence in Corsica, we surveyed 11 geographically distant sheep or goat farms. Using molecular tools such as nested PCR targeting 16S ribosomal RNA (rRNA), citrate synthase (gltA) and heat-shock protein (groEL) genes, we detected the presence of A. capra on 5/11 farms, in 26/108 blood samples (24%), in sheep as well as in goats. Genotyping and phylogenetic analysis of A. capra revealed that isolates from Corsica island grouped closely with A. capra isolates reported in red deer and swamp deer from a zoological reserve in mainland France, as well as in roe deer from Spain, in a separate and well supported clade within A. capra clade II. This third report of the tick-borne bacterium A. capra in Europe suggests a potentially larger presence of this pathogen on the European continent, on domestic, native as well as wild ruminants, a broad host range already described in Asian countries for this species. 相似文献
10.