全文获取类型
收费全文 | 319篇 |
免费 | 16篇 |
国内免费 | 13篇 |
专业分类
儿科学 | 34篇 |
妇产科学 | 3篇 |
基础医学 | 41篇 |
口腔科学 | 12篇 |
临床医学 | 33篇 |
内科学 | 54篇 |
皮肤病学 | 7篇 |
神经病学 | 7篇 |
特种医学 | 93篇 |
外科学 | 9篇 |
综合类 | 4篇 |
预防医学 | 8篇 |
眼科学 | 10篇 |
药学 | 13篇 |
肿瘤学 | 20篇 |
出版年
2022年 | 2篇 |
2021年 | 3篇 |
2020年 | 1篇 |
2019年 | 2篇 |
2018年 | 3篇 |
2017年 | 3篇 |
2016年 | 3篇 |
2015年 | 12篇 |
2014年 | 5篇 |
2013年 | 9篇 |
2012年 | 8篇 |
2011年 | 1篇 |
2010年 | 13篇 |
2009年 | 10篇 |
2008年 | 5篇 |
2007年 | 10篇 |
2006年 | 6篇 |
2005年 | 3篇 |
2004年 | 4篇 |
2003年 | 4篇 |
2002年 | 6篇 |
2001年 | 2篇 |
2000年 | 18篇 |
1999年 | 3篇 |
1998年 | 25篇 |
1997年 | 39篇 |
1996年 | 27篇 |
1995年 | 18篇 |
1994年 | 14篇 |
1993年 | 6篇 |
1992年 | 4篇 |
1991年 | 1篇 |
1990年 | 4篇 |
1989年 | 11篇 |
1988年 | 10篇 |
1987年 | 1篇 |
1986年 | 5篇 |
1985年 | 5篇 |
1984年 | 2篇 |
1983年 | 10篇 |
1982年 | 5篇 |
1981年 | 3篇 |
1980年 | 5篇 |
1978年 | 2篇 |
1977年 | 7篇 |
1976年 | 4篇 |
1975年 | 3篇 |
1973年 | 1篇 |
排序方式: 共有348条查询结果,搜索用时 0 毫秒
121.
Suprasellar lesions: evaluation with MR imaging 总被引:2,自引:0,他引:2
The authors retrospectively evaluated the characteristics on magnetic resonance (MR) images of 59 suprasellar lesions and compared them with computed tomography (CT) scans in 55 of the cases in which CT was performed. A diverse number of lesions were included: 17 pituitary adenomas; eight optic or hypothalamic gliomas; six craniopharyngiomas; six vascular anomalies; four lesions with extension into the suprasellar space; three metastases; two each of meningioma, hamartoma, germinoma, sarcoid granuloma, and teratoma; and one each of lymphoma, optic tract hematoma, cerebrospinal fluid-borne metastasis, pituitary hyperplasia, and sphenoid sinus mucocele. MR enabled characterization of lesions containing hemorrhage, fat, flowing blood, mucus, and cyst and allowed more specific diagnoses than CT in 6% of cases. MR was equivalent to CT in allowing lesions to be detected and in 20% of cases more accurately defined altered perisellar anatomy. Vascular abnormalities can be better evaluated with MR, and use of angiography can be avoided in some cases. 相似文献
122.
A variation of temporal recursive filtering for intravenous and intra-arterial digital subtraction angiography (DSA) is described. It results in a dynamic tomographic DSA display that may improve intravenous DSA performance by removing the confusion introduced by vessel overlap and reducing the severity of motion artifacts. A conventional circular tomographic apparatus was modified by the addition of a 23-cm image intensifier-television chain and made to run continuously at one revolution each 1.5 seconds. The video output was processed by the recursive filter in a two-step process resulting in a dynamic tomographic display of arterial opacification. Theory and results of initial animal studies are presented. 相似文献
123.
Results of percutaneous transluminal angioplasty 总被引:2,自引:0,他引:2
Percutaneous transluminal angioplasty (Dotter technique) was used in 2,942 cases of iliofemoral atheromatous disease. Results varied with the characteristics of the obstructing lesion (length and location) and the clinical stage of ischemia (claudication, rest pain, gangrene). Based on the foregoing, angioplasty is done either as the preferred primary treatment or for the relief of clinically advanced disease in patients unsuitable for high risk surgery. Success is favored by the use of aggregation inhibitors and single-use Teflon or balloon catheters; complications are few. 相似文献
124.
125.
Rhabdomyosarcomas in the head and neck: MR imaging evaluation 总被引:2,自引:0,他引:2
126.
Romero FI; Amengual O; Atsumi T; Khamashta MA; Tinahones FJ; Hughes GR 《Rheumatology (Oxford, England)》1998,37(8):883-888
The prevalence and clinical significance of antibodies against beta2-
glycoprotein I (anti-beta2GPI) and antibodies against oxidized low- density
lipoprotein (anti-ox-LDL) were evaluated as potential indicators of
arterial disease in patients with systemic lupus erythematosus (SLE) and
SLE with secondary antiphospholipid syndrome (APS). IgG anti-beta2GPI and
IgG anti-ox-LDL were measured by enzyme- linked immunosorbent assay (ELISA)
in serum samples from 118 patients with SLE, including 40 with secondary
APS. IgG anti-beta2GPI were positive in 17% (20/118) of SLE patients. The
presence and titres of IgG anti-beta2GPI were strongly associated with a
history of arterial thrombosis. Haemolytic anaemia was also significantly
associated with the presence of IgG anti-beta2GPI. The prevalence of IgG
anti-ox-LDL was 53% (63/118), but there was no association with arterial
thrombosis. No correlation between the values of anti-ox-LDL and those of
anti-beta2GPI was found. These results suggest that IgG anti- beta2GPI
could be a marker for arterial thrombosis in SLE patients, while IgG
anti-ox-LDL were not associated with arterial disease in this group of
lupus patients.
相似文献
127.
Martin?N?MwangiEmail author Sumi?Maskey Pauline?EA?Andang’o Noel?K?Shinali Johanna?M?Roth Laura?Trijsburg Alice?M?Mwangi Han?Zuilhof Barend?van Lagen Huub?FJ?Savelkoul Ay?e?Y?Demir Hans?Verhoef 《BMC medicine》2014,12(1):229
Background
Iron-deficient erythropoiesis results in excess formation of zinc protoporphyrin (ZPP), which can be measured instantly and at low assay cost using portable haematofluorometers. ZPP is used as a screening marker of iron deficiency in individual pregnant women and children, but also to assess population iron status in combination with haemoglobin concentration. We examined associations between ZPP and disorders that are common in Africa. In addition, we assessed the diagnostic utility of ZPP (measured in whole blood and erythrocytes), alone or in combination with haemoglobin concentration, in detecting iron deficiency (plasma ferritin concentration <15 μg/L).Methods
Single blood samples were collected from a population sample of 470 rural Kenyan women with singleton pregnancies, gestational age 13 to 23 weeks, and haemoglobin concentration ≥90 g/L. We used linear regression analysis to assess associations between ZPP and iron markers (including anaemia), factors known or suspected to be associated with iron status, inflammation markers (plasma concentrations of C-reactive protein and α 1-acid glycoprotein), infections (Plasmodium infection, HIV infection), and other disorders (α +-thalassaemia, plasma concentrations of total bilirubin, and lactate dehydrogenase). Subsequently, in those without inflammation, Plasmodium infection, or HIV infection, we used logistic discriminant analysis and examined receiver operating characteristics curves with corresponding area-under-the-curve to assess diagnostic performance of ZPP, alone and in combination with haemoglobin concentration.Results
Individually, whole blood ZPP, erythrocyte ZPP, and erythrocyte protoporphyrin had limited ability to discriminate between women with and without iron deficiency. Combining each of these markers with haemoglobin concentration had no additional diagnostic value. Conventional cut off points for whole blood ZPP (>70 μmol/mol haem) resulted in gross overestimates of the prevalence of iron deficiency.Conclusions
Erythrocyte ZPP has limited value to rule out iron deficiency when used for screening in conditions with a low prevalence (e.g., 10%). ZPP is of unreliable diagnostic utility when discriminating between pregnant women with and without iron deficiency. Based on these findings, guidelines on the use of ZPP to assess iron status in individuals or populations of pregnant women need review.Trial registration
NCT01308112 (2 March 2011).128.
129.
WM HUI J HO BW CHEN C-H CHO FJ BRANICKI SK LAM 《Journal of gastroenterology and hepatology》1997,12(1):7-12
We compared the effects of misoprostol, omeprazole and methylcellulose (control) on gastric mucosal injury induced by nicotine and/or ethanol. The results demonstrate that misoprostol and omeprazole each significantly reduce macroscopic injury and deep injury at a microscopic level (P < 0.05) induced by nicotine alone, ethanol alone or a combination of ethanol and nicotine. Misoprostol and omeprazole each reduced the leakage of fluorescein isothiocyanate-albumin into the interstitium in the gastric mucosa. Misoprostol and omeprazole are each effective in preventing injury induced by nicotine and ethanol and vascular factors are involved. 相似文献
130.
This study describes the use of radiologic methods in the identification of 256 bodies after the crash of an airliner in Gander, Newfoundland. Two hundred thirty-one (90%) of the victims were identified positively with dental and/or fingerprint comparisons. Radiologic data confirmed identification in 29 of these victims. Seventeen bodies without dental or fingerprint identification were presumptively identified with a variety of data, which included radiologic characteristics in four cases. Eight bodies were identified with an exclusion matrix. Radiologic input was critical in two of these. The procedures described provide practical information for radiologists in a mass casualty disaster investigation. 相似文献