全文获取类型
收费全文 | 5235篇 |
免费 | 257篇 |
国内免费 | 169篇 |
专业分类
耳鼻咽喉 | 94篇 |
儿科学 | 37篇 |
妇产科学 | 47篇 |
基础医学 | 880篇 |
口腔科学 | 114篇 |
临床医学 | 559篇 |
内科学 | 1038篇 |
皮肤病学 | 116篇 |
神经病学 | 459篇 |
特种医学 | 320篇 |
外科学 | 725篇 |
综合类 | 32篇 |
预防医学 | 207篇 |
眼科学 | 56篇 |
药学 | 510篇 |
中国医学 | 76篇 |
肿瘤学 | 391篇 |
出版年
2024年 | 1篇 |
2023年 | 44篇 |
2022年 | 167篇 |
2021年 | 241篇 |
2020年 | 109篇 |
2019年 | 124篇 |
2018年 | 151篇 |
2017年 | 123篇 |
2016年 | 194篇 |
2015年 | 337篇 |
2014年 | 350篇 |
2013年 | 385篇 |
2012年 | 563篇 |
2011年 | 538篇 |
2010年 | 273篇 |
2009年 | 246篇 |
2008年 | 328篇 |
2007年 | 340篇 |
2006年 | 244篇 |
2005年 | 172篇 |
2004年 | 109篇 |
2003年 | 97篇 |
2002年 | 85篇 |
2001年 | 80篇 |
2000年 | 75篇 |
1999年 | 48篇 |
1998年 | 47篇 |
1997年 | 17篇 |
1996年 | 20篇 |
1995年 | 26篇 |
1994年 | 26篇 |
1993年 | 19篇 |
1992年 | 21篇 |
1991年 | 10篇 |
1990年 | 11篇 |
1989年 | 9篇 |
1988年 | 9篇 |
1987年 | 6篇 |
1986年 | 6篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1980年 | 1篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 2篇 |
排序方式: 共有5661条查询结果,搜索用时 15 毫秒
991.
BACKGROUND: The recent introduction of urea sensors for dialysis monitoring
has made possible new approaches to urea kinetic modelling. In this study
we show how the equilibrated postdialysis urea concentration (Ceq) and Kt/V
corrected for double-pool urea kinetics (Kt/Vdp) can be accurately
determined using an on-line sensor providing a continuous measure of blood
water urea. A modification of the Smye constant volume double-pool theory
led to the following equations for Ceq and Kt/Vdp [formula: see text] where
Cpre is the blood concentration measured at the start of dialysis, t is the
length of the dialysis session (in min) and S(ex) is the constant slope of
the blood urea logarithm concentration decline following development of the
intercompartmental urea concentration gradient in the first 30-60 min of
dialysis. METHODS: These equations were tested in 11 patients undergoing
165-240 min of paired filtration dialysis with continuous monitoring of
blood urea concentration. Cpre was determined as the plateau concentration
during a preliminary period of 15-20 min of slow isolated ultrafiltration.
S(ex) was accurately determined from linear regression applied to the urea
sensor data from the 80-min point to the end of dialysis. RESULTS: Ceq and
Kt/Vdp determined from the above equations compared closely to values
determined from 25-40 min of urea rebound monitoring with the urea sensor:
10.6 +/- 3.0 versus 10.8 +/- 2.7 mmol/l (mean +/- SD) for Ceq and 1.21 +/-
0.24 versus 1.18 +/- 0.20 for Kt/Vdp, compared to single-pool values of
Kt/V = 1.34 +/- 0.23. CONCLUSION: This technique may be readily programmed
into on-line urea monitors to provide current and extrapolated values of
Ceq and Kt/Vdp from about the first hour of dialysis.
相似文献
992.
JP Damsin JY Zambelli R Ma J Roume F Colonna L Hannoun 《Surgical and radiologic anatomy : SRA》1995,17(1):13-17
Summary Varus deformity of the knee is common in young children who have suffered from fulminating purpura. This study was directed at the anatomic features of the vascularisation of the upper end of the tibia that might account for such deformation. It was based on the dissection of 28 anatomic specimens prepared by injection of Indian ink into the vascular trunk. 16 specimens were diaphanised for better analysis of the intracartilaginous distribution of the vessels. The study showed that the vascularisation of the medial condyle of the tibia is poor and of terminal nature, which may explain the occurrence of ischemic growth disorders following fulminating purpura.
Etude de la vascularisation artérielle du condyle médial du tibia chez le foetus
Résumé Les déformations en varus du genou chez les jeunes enfants ayant présenté un purpura fulminans sont fréquentes. Ce travail a pour objet de rechercher les caractéristiques anatomiques de la vascularisation de l'extrémité supérieure du tibia qui peuvent expliquer ces déformations. L'étude porte sur la dissection de 28 pièces anatomiques préparées par injection de l'axe vasculaire à l'encre de Chine. Pour mieux analyser la répartition intra-cartilagineuse des vaisseaux, 16 pièces ont été diaphanisées. Cette étude montre que la vascularisation du condyle médial du tibia est pauvre, de type terminal, ce qui peut expliquer la survenue de troubles de croissance ischémiques dans les suites d'un purpura fulminans.相似文献
993.
994.
Han JY; Kim HK; Choi BG; Moon H; Hong YS; Lee KS 《Japanese journal of clinical oncology》1998,28(12):749-753
BACKGROUND: Quality of life (QOL) assessment has emerged to measure and
quantify the balance between treatment benefit and toxicity, and has a
value in predicting response and overall survival in cancer patients.
METHODS: From July 1995 to February 1997, 38 symptomatic patients with
advanced non-small cell lung cancer (NSCLC) were treated with MIP
chemotherapy (mitomycin 6 mg/m2, ifosfamide 3000 mg/m2 and cisplatin 50
mg/m2 on day 1 every 3 weeks). Patients were assessed for QOL including
physical well-being, general symptoms and lung cancer-specific symptoms, as
well as objective response. RESULTS: The overall response rate was 38.9%
(14/36, all were partial response) and the median duration of response was
3.5 months [95% confidence interval (CI) 2.0-4.0]. The median duration of
overall survival was 7 months (95% CI 5.9-8.5). The overall improvement of
QOL was 58.3% with 21 patients feeling better on treatment. The toxicity of
chemotherapy was mild, mainly nausea/vomiting and minimal alopecia. Using
multiple clinical predictors of survival (age, histology, stage,
performance status), only change of QOL emerged significantly (P = 0.0007).
CONCLUSIONS: MIP had an endurable response and low toxicity profile, and
provided good QOL. Integral QOL data in our study provided the strong
prediction of survival in advanced NSCLC. Further experienced QOL study
will provide greatly enhanced outcome data in clinical trials.
相似文献
995.
Nam Jin Cho Sang Hyun Sung Heum Sook Lee Mee Hee Jeon Young Choong Kim 《Archives of pharmacal research》1995,18(4):289-292
Icariside II, a flavonol glycoside, was isolated from the aerial part ofEpimedium koreanum Nakai by the anti-hepatotoxic activity guided fractionation technique employing CCl4-intoxicated primary cultured rat hepatocytes as an assay system. Its anti-hepatotoxic activity was evaluated by measuring activity of glutamic pyruvic transaminase released from the CCl4-in-toxicated primary cultured rat hepatocytes. Icariside II significantly reduced the activity of glutamic pyruvic transaminase released from the CCl4-intoxicated primary cultured rat hepatocytes and resulted in 78% recovery of the toxicity at the concentration of 200 μM. The antihepatotoxic activity of icariside II on the CCl4-intoxicated primary cultured rat hepatocytes was as potent as that of silybin. 相似文献
996.
Activation of NF-kappaB/Rel in angelan-stimulated macrophages. 总被引:3,自引:0,他引:3
997.
Lee SK Jeon TW Kim YB Lee ES Jeong HG Jeong TC 《Journal of applied toxicology : JAT》2007,27(4):358-367
1-Bromopropane (1-BP) is used as a cleaning agent or adhesive solvent in the workplace. In the present study, the hepatotoxic and immunotoxic effects of 1-bromopropane and its conjugation with glutathione (GSH) were investigated in female BALB/c mice. The animals were treated orally with 200, 500 and 1000 mg kg(-1) of 1-BP in corn oil for a dose response study or treated orally with 1000 mg kg(-1) of 1-BP for 6, 12, 24 and 48 h for a time course study. The hepatic and splenic contents of GSH were significantly decreased by 1-BP in a dose-dependent manner. S-propyl GSH was identified in livers following treatment with 1-BP by liquid chromatography-electrospray ionization tandem mass spectrometry. When the production of conjugates from 1-BP was investigated in livers following oral treatment with 1000 mg kg(-1) of 1-BP for 6, 12, 24 and 48 h, the GSH conjugates were detected maximally 6 h after treatment. Treatment of mice with 1-BP increased the serum activity of alanine aminotransferase dose-dependently. The oral 1-BP treatment significantly suppressed the antibody response to a T-dependent antigen and the production of splenic intracellular IL-2 in response to Con A in a dose-dependent manner. The present results suggested that 1-BP could cause hepatotoxicity and immunotoxicity as well as depletion of GSH content due to the formation of GSH conjugates. 相似文献
998.
Thiazolidinedione derivatives are potential antidiabetic drugs that bind and activate peroxisome proliferator activated receptor gamma (PPARgamma), which is a member of the nuclear hormone receptor superfamily and enhances insulin sensitivity. In an effort to develop a novel and effective thiazolidindione derivative, 5-{4-[2-(methyl-p-substituted phenylamino) ethoxy] benzyl} thiazolidine-2,4-diones 7 have been prepared by Mitsunobu reaction of the hydrophobic segment, methyl-p-substituted phenylaminoethanol 4 with hydroxybenzylthiazolidinedione 5 and their ability to activate PPARgamma and inhibit LPS-induced NO production were evaluated. 相似文献
999.
Flavone inhibits vascular contraction by decreasing phosphorylation of the myosin phosphatase target subunit 总被引:1,自引:0,他引:1
Jeon SB Kim G Kim JI Seok YM Kim SH Suk K Shin HM Lee YH Kim IK 《Clinical and experimental pharmacology & physiology》2007,34(11):1116-1120
1. Flavonoids modulate vascular tone through an endothelium-dependent or -independent mechanism. Although a few mechanisms for endothelium-independent relaxation have been suggested, such as interference with protein kinase C or cAMP or cGMP phosphodiesterase, the inhibition of Ca(2+) release from intracellular stores or Ca(2+) influx from extracellular fluids, the mode of action of flavonoids remains elusive. 2. We hypothesized that treatment with flavone inhibits vascular smooth muscle contraction by decreasing the phosphorylation of the myosin phosphatase target subunit (MYPT1). 3. Rat aortic rings were denuded of endothelium, mounted in organ baths and contracted with U46619, a thromboxane A(2) analogue. 4. Flavone dose-dependently inhibited the U46619-induced contractile response and myosin light chain (MLC(20)) phosphorylation. At 10(-7) mol/L, U46619 induced vascular contraction with the concomitant phosphorylation of MYPT1 at Thr855, but not at Thr697. Incubation with flavone (100 or 300 micromol/L) for 30 min attenuated the phosphorylation of MYPT1(Thr855), but not MYPT1(Thr697). 5. It is concluded that treatment with flavone inhibits vascular smooth muscle contraction by decreasing the phosphorylation of the MYPT1. These results suggest that flavone causes endothelium-independent relaxation through, at least in part, the inhibition of p160 Rho-associated coiled-coil-containing protein kinase (ROCK) signalling. 相似文献
1000.
This study reports an autopsy case of a 53 year-old male with rapidly progressive extra-nodal NK/T-cell lymphoma accompanied with unusual clinical and pathologic features. He was initially presented with localized swelling and tenderness in the right lower extremity and the biopsy from the calf muscle was interpreted as granulomatous myositis masquerizing lymphoma. The biopsy from erythematous skin lesion of trunk showed infiltration of medium sized atypical lymphoid cells with relatively plump cytoplasm and immunophenotype of CD30+, CD56+/- and surface CD3-, which lead to the diagnosis of CD30+ anaplastic large cell lymphoma. About 2 months later, nasal obstruction was developed and the nasal biopsy was done. After confirmation of EBV infection, he was finally diagnosed as extra-nodal NK/T-cell lymphoma with peculiar immunophenotype of CD3 dim+ and CD30+. Despite the chemotherapy, he was going rapidly downhill and died of respiratory and multi-organ failure 8 months after the onset of soft tissue lesion. At autopsy, disseminated angiocentric lymphoma was found all over the internal organs including the brain. This case emphasizes that extra-nodal NK/T-cell lymphoma should be considered as a cause of granulomatous myositis and can express CD30 positivity and CD3 weak positivity, which are unusual but rarely predominant feature of NK/T-cell lymphoma. 相似文献