全文获取类型
收费全文 | 35091篇 |
免费 | 2236篇 |
国内免费 | 102篇 |
专业分类
耳鼻咽喉 | 499篇 |
儿科学 | 874篇 |
妇产科学 | 491篇 |
基础医学 | 4207篇 |
口腔科学 | 456篇 |
临床医学 | 3782篇 |
内科学 | 7167篇 |
皮肤病学 | 446篇 |
神经病学 | 3059篇 |
特种医学 | 1414篇 |
外科学 | 5907篇 |
综合类 | 392篇 |
一般理论 | 40篇 |
预防医学 | 3175篇 |
眼科学 | 529篇 |
药学 | 2613篇 |
中国医学 | 36篇 |
肿瘤学 | 2342篇 |
出版年
2024年 | 27篇 |
2023年 | 250篇 |
2022年 | 478篇 |
2021年 | 1095篇 |
2020年 | 644篇 |
2019年 | 992篇 |
2018年 | 1189篇 |
2017年 | 828篇 |
2016年 | 831篇 |
2015年 | 997篇 |
2014年 | 1500篇 |
2013年 | 1977篇 |
2012年 | 2838篇 |
2011年 | 2905篇 |
2010年 | 1532篇 |
2009年 | 1416篇 |
2008年 | 2441篇 |
2007年 | 2365篇 |
2006年 | 2194篇 |
2005年 | 2230篇 |
2004年 | 2087篇 |
2003年 | 1859篇 |
2002年 | 1724篇 |
2001年 | 214篇 |
2000年 | 190篇 |
1999年 | 234篇 |
1998年 | 322篇 |
1997年 | 243篇 |
1996年 | 239篇 |
1995年 | 170篇 |
1994年 | 170篇 |
1993年 | 143篇 |
1992年 | 117篇 |
1991年 | 99篇 |
1990年 | 90篇 |
1989年 | 81篇 |
1988年 | 82篇 |
1987年 | 57篇 |
1986年 | 44篇 |
1985年 | 51篇 |
1984年 | 66篇 |
1983年 | 66篇 |
1982年 | 76篇 |
1981年 | 47篇 |
1980年 | 38篇 |
1979年 | 24篇 |
1978年 | 21篇 |
1977年 | 22篇 |
1975年 | 16篇 |
1974年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
Kevin L. Billups 《Current Sexual Health Reports》2004,1(4):137-141
Erectile dysfunction (ED) is often not considered in the same context as such traditional cardiovascular conditions as hypertension,
dyslipidemia, diabetes, or ischemic heart disease. The detection of ED might be one of the most powerful tools to help manage
cardiovascular disease in men. Clinical research suggests that the penile vascular bed is a sensitive indicator of early systemic
endothelial cell or smooth muscle dysfunction. ED could be one of the initial signs of oxidative stress that occurs before
the development of the structural, occlusive cardiovascular disease. ED is becoming a barometer of overall global cardiovascular
risk and should be viewed in this context rather than as “just a problem with the penis.” Asking men about ED as part of the
review of systems is an effective means of practicing preventive vascular medicine. 相似文献
83.
Kevin Roy Forward 《The Canadian Journal of Infectious Diseases & Medical Microbiology》1992,3(1):19-22
Branhamella catarrhalis is being isolated with increasing frequency from patients with symptoms and signs of respiratory tract infection. Records of 77 patients were reviewed to define the spectrum of respiratory illness and to compare clinical and laboratory features with those of respiratory infection due to Haemophilus influenzae. Both B catarrhalis and H influenzae caused respiratory infection predominantly in elderly males with underlying heart or lung disease. There were no clinical or laboratory features aside from sputum Gram stain and culture which differentiated the two groups. Although fewer than one-half of each group received antibiotics, no patient developed progressive respiratory disease. 相似文献
84.
Kevin M Kernek Matteo Brunelli Thomas M Ulbright John N Eble Guido Martignoni Shaobo Zhang Helen Michael Oscar W Cummings Liang Cheng 《Modern pathology》2004,17(11):1309-1313
The over-representation of chromosome 12p sequences is crucial for the development of invasive testicular germ cell tumors. Testicular cancer patients may have metastatic tumors of diverse histologic types, including adenocarcinoma, undifferentiated carcinoma, sarcoma, or other malignancies that lack features of germ cell tumors. We sought to investigate the possible germ cell origin of such tumors using interphase fluorescence in situ hybridization. In all, 10 metastatic malignant somatic-type tumors from patients with histories of testicular cancer, as well as one malignant somatic-type tumor from a patient with primary mediastinal germ cell tumor were studied and included: adenocarcinoma (five cases), poorly differentiated carcinoma (one), sarcoma (four), and neuroendocrine carcinoma (one). The tumors were analyzed using fluorescence in situ hybridization using 12p spectrum green and 12 centromeric spectrum orange probes in paraffin sections. The patients ranged in age from 27 to 55 years (mean, 43). Colon and lung cancers from patients without germ cell tumors were used as controls. Adequate signals were observed in all tumors. Gain of chromosome 12p was seen in six tumors. None of the control tumors showed 12p amplification. Fluorescence in situ hybridization for 12p amplification in routinely processed surgical specimens is a useful adjuvant diagnostic tool in confirming the germ cell origin of metastatic tumors having the histologic appearance of somatic-type neoplasms. 相似文献
85.
Wilfrid No?l Raby Patricia A Modica Robyn J Wolintz Kevin Murtaugh 《Journal of ocular pharmacology and therapeutics》2006,22(1):68-75
A case is presented in which a woman diagnosed with a longstanding history of idiopathic intracranial hypertension reported improvement of frontal headaches, photophobia, transient blindness, enlarged blind spots, and tinnitus after smoking marijuana. All these symptoms and signs were associated with increased intracranial pressure (220-425 mm of water). Treatment with dronabinol at a dose of 10 mg twice a day, then reduced to 5 mg twice a day, relieved all of her symptoms. Previously noted papilledema and enlargement of blind spots also resolved, and this, in the absence of psychoactive effect or weight gain. 相似文献
86.
Student near-peer co-tutors in PBL groups 总被引:1,自引:0,他引:1
87.
Kevin J. Donly DDS MS 《Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]》2005,17(6):380-380
The popularity of vital tooth whitening has increased significantly over the past two decades. Professionally supervised "in-office" and "at-home" tooth whitening methods have been documented in the literature with evidence of safety and effectiveness. Although the literature includes considerable information about vital tooth whitening in adults, minimal information is available concerning vital tooth whitening in children and adolescents.
The need to provide vital tooth whitening for children might be infrequent owing to the natural whiteness of children's teeth. However, there are circumstances when tooth whitening can be desirable for children, such as fluorosis discoloration, generalized tooth darkening, post-traumatic injury discoloration, and postorthodontic tooth discoloration.
Few well-controlled clinical trials evaluating the safety and effectiveness of vital tooth whitening in children are available in the literature, Furthermore, these published clinical trials were carried out by the same principal investigator. This review examines these trials and offers recommendations accordingly. 相似文献
The need to provide vital tooth whitening for children might be infrequent owing to the natural whiteness of children's teeth. However, there are circumstances when tooth whitening can be desirable for children, such as fluorosis discoloration, generalized tooth darkening, post-traumatic injury discoloration, and postorthodontic tooth discoloration.
Few well-controlled clinical trials evaluating the safety and effectiveness of vital tooth whitening in children are available in the literature, Furthermore, these published clinical trials were carried out by the same principal investigator. This review examines these trials and offers recommendations accordingly. 相似文献
88.
Mary M. Klote Lawrence Y. Agodoa Kevin Abbott 《American journal of transplantation》2004,4(9):1523-1528
The incidence, risk factors, and prognosis for Mycobacterium tuberculosis (MTB) infection have not been reported in a national population of renal transplant recipients. We performed a retrospective cohort study of 15,870 Medicare patients who received renal transplants from January 1, 1998 to July 31, 2000. Cox regression analysis derived adjusted hazard ratios (AHR) for factors associated with a diagnosis of MTB infection (by Medicare Institutional Claims) and the association of MTB infection with survival. There were 66 renal transplant recipients diagnosed with tuberculosis infection after transplant (2.5 cases per 1000 person years at risk, with some falling off of cases over time). The most common diagnosis was pulmonary TB (41 cases). In Cox regression analysis, only systemic lupus erythematosus (SLE) was independently associated with TB. Mortality after TB was diagnosed was 23% at 1 year, which was significantly higher than in renal transplant recipients without TB (AHR, 4.13, 95% CI, 2.21, 7.71, p < 0.001). Although uncommon, MTB infection is associated with a substantially increased risk of mortality after renal transplantation. High-risk groups, particularly those with SLE prior to transplant, might benefit from intensified screening. 相似文献
89.
Stomach rupture can occur as a consequence of the expansion of compressed air during rapid ascent after diving. We present
the case of a middle-aged woman who suffered a gastric tear from surfacing too quickly after diving, and discuss the diagnosis
and management of such patients by reviewing previously reported similar events. Gastric barotrauma should be suspected in
divers who complain of abdominal pain, even in the absence of frank signs of peritoneal irritation. Although pneumoperitoneum
is always present in these patients, it can also occur as a consequence of pulmonary barotrauma, making gastroscopy or radiological
contrast studies, or both, essential for a definitive diagnosis. Surgical repair represents the treatment of choice for an
active full-thickness tear and, if associated with arterial gas embolism or decompression sickness, should ideally be performed
in a center where a category I (intensive care-capable) hyperbaric unit is available.
Received: March 18, 2002 / Accepted: September 3, 2002
Reprint requests to: L.V. Titu 相似文献
90.