全文获取类型
收费全文 | 502篇 |
免费 | 47篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 5篇 |
妇产科学 | 13篇 |
基础医学 | 76篇 |
口腔科学 | 5篇 |
临床医学 | 43篇 |
内科学 | 105篇 |
皮肤病学 | 9篇 |
神经病学 | 60篇 |
特种医学 | 19篇 |
外科学 | 42篇 |
综合类 | 4篇 |
一般理论 | 1篇 |
预防医学 | 30篇 |
眼科学 | 36篇 |
药学 | 30篇 |
中国医学 | 6篇 |
肿瘤学 | 61篇 |
出版年
2023年 | 11篇 |
2022年 | 16篇 |
2021年 | 33篇 |
2020年 | 14篇 |
2019年 | 23篇 |
2018年 | 27篇 |
2017年 | 13篇 |
2016年 | 12篇 |
2015年 | 14篇 |
2014年 | 15篇 |
2013年 | 22篇 |
2012年 | 32篇 |
2011年 | 21篇 |
2010年 | 16篇 |
2009年 | 7篇 |
2008年 | 28篇 |
2007年 | 22篇 |
2006年 | 24篇 |
2005年 | 25篇 |
2004年 | 21篇 |
2003年 | 20篇 |
2002年 | 24篇 |
2001年 | 23篇 |
2000年 | 22篇 |
1999年 | 12篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 4篇 |
1995年 | 3篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 6篇 |
1991年 | 7篇 |
1990年 | 6篇 |
1989年 | 6篇 |
1988年 | 1篇 |
1987年 | 4篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1981年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有550条查询结果,搜索用时 15 毫秒
81.
P N Vuong 《Diagnostic cytopathology》1988,4(2):137-139
A case of acquired myospherulosis of the right gluteal region diagnosed by FNA cytology is reported in a woman who had received a series of intramuscular injections of petrolatum-based hormones. The lesion is characterized by inflammatory pseudocystic nodules containing saccular formations with erythrocytes or "bags of marbles." It results from a physical process similar to the emulsion phenomenon between nonresorbent oily material and plasma. This process gives rise to sequestration of blood corpuscles by oily materials and thus development of foreign body granulomas. 相似文献
82.
C R Freeman S Suissa G Shenouda T Vuong L Souhami M Pla E B Podgorsak C Pla 《Radiotherapy and oncology》1992,24(3):155-162
Between October 1981 and December 1989, 44 patients with cutaneous T-cell lymphoma (CTCL) were treated with a single field rotational total skin electron irradiation (RTSEI) technique developed in the McGill University, Department of Radiation Oncology. Only 11 (25%) of the 44 patients had received no prior treatment. Three-quarters (33/44) had advanced (T3 or T4) disease. Complete responses were seen in 32/44 (73%) of patients (91% T2, 71% T3 and 58% T4), but only 3/11 (27%) of patients with T2 disease and 3/21 (14%) of patients with T3 disease remain in continuous complete remission in the skin, after median intervals of 58 and 35 months, respectively. Median cause-specific survival for the whole group is 43 months and survival at 5 years is 38%. Survival was significantly better for patients with T2 disease than for patients with T3 disease (relative risk 4.3; 95% CI 1.4-13.2) and patients with T4 disease (relative risk 3.1; 95% CI 0.8-12.1). The RTSEI technique used at McGill has depth-dose characteristics and photon contamination similar to other commonly used TSEI techniques. It is relatively simple and provides a homogenous dose distribution over the entire skin surface in a short treatment time. Results of treatment are similar to those obtained with other techniques. For T2 disease, TSEI is an effective treatment modality with a possibility of long-term tumor control. For more advanced disease, more aggressive treatment, which may include TSEI, is necessary. 相似文献
83.
In the present study, we tested the extent to which observers use dynamic information to detect targets in natural scenes. For this purpose, we used composite stimuli in which target sequences were superimposed onto distractor sequences. We varied target visibility in the composite sequence, and the presence or absence of motion. Across four experiments, we found a dynamic advantage for target detection: Observers performed more accurately with dynamic than static target scenes. This advantage depended on the availability of target motion, irrespective of whether the target was upright or inverted in the image plane (Experiments 1-4). The magnitude of this advantage also depended on the availability of segmentation cues (Experiments 1 and 2) and on the distractors used (Experiments 2 and 4). Overall, the dynamic advantage reported extends previous work using isolated dynamic objects to more complex scenes. 相似文献
84.
D. Amat Pr J. P. Camilleri Vuong Ngoc Phat J. Bariety P. Corvol J. Menard 《Virchows Archiv : an international journal of pathology》1981,390(2):193-204
Summary The distribuation of renin in two cases of segmental renal hypoplasia was investigated by immunofluorescence and the peroxidase anti-peroxidase (PAP) method using an anti-human renin antiserum. Renin-containing cells were found only in hypoplasic segments in the vicinity of altered glomeruli and small arteries. Well-preserved renal cortex and areas of chronic atrophic pyelonephritis failed to show any demonstrable site of renin production.Whatever is the mechanism of the disease, the characterization of large numbers of renin-containing cells in the affected kidney support a role for the renin-angiotensin system stimulation in this form of hypertension. 相似文献
85.
The predictive value of apoptosis protease-activating factor 1 in rectal tumors treated with preoperative, high-dose-rate brachytherapy 总被引:3,自引:0,他引:3
BACKGROUND: The objective of this study was to assess the value of apoptosis protease-activating factor 1 (APAF-1) as a predictive marker of response in rectal tumors treated with preoperative, high-dose-rate endorectal brachytherapy. METHODS: Immunohistochemistry for APAF-1 was performed on 94 rectal tumor biopsy specimens from patients who were treated on a preoperative, high-dose-rate brachytherapy protocol. Tumors were considered positive when > 10% of tumor cells were immunoreactive. The association between APAF-1 expression and tumor response was made using the chi-square test. RESULTS: Forty-four tumors (43%) were positive for APAF-1. Thirty tumors had complete pathologic tumor regression after preoperative radiotherapy. Of these, 18 tumors were positive for APAF-1. A partial response occurred in 35 tumors. Eighteen tumors (51%) were positive for the protein. Only 8 of 29 nonresponsive tumors (28%) were immunoreactive for APAF-1. A significant association was found between complete tumor regression and positive APAF-1 status (P = 0.018). APAF-1 expression in partially responsive tumors was significantly greater than in nonresponsive tumors (P = 0.03). CONCLUSIONS: APAF-1 expression in pretreatment rectal tumor biopsy specimens may be useful as a predictive marker of response to preoperative radiotherapy in patients with rectal carcinoma. 相似文献
86.
A nematocidal agent present in a southern Australian marine sponge of the genus Echinodictyum has been isolated and identified by detailed spectroscopic analysis and total synthesis as the novel betaine (-)-echinobetaine A (6). Preliminary SAR investigations have been undertaken. 相似文献
87.
van der Ham L Wright P Van TV Doan VD Broerse JE 《Community mental health journal》2011,47(5):574-582
This explorative study assesses perceptions of mental health and help-seeking behavior among adults in Vietnam. Methods included
questionnaires (200) and focus group discussions (eight). Respondents were often unable to name specific mental illnesses.
Frequently mentioned symptoms of mental illness were talking nonsense, talking/laughing alone and wandering. Pressure/stress
and studying/thinking too much were often identified causes. Most respondents showed a preference for medical treatment options,
often in combination with family care. The results show that perceptions of mental health and help-seeking behaviour are influenced
by a lack of knowledge and a mix of traditional and modern views. 相似文献
88.
89.
Oehler C Dickinson DJ Broggini-Tenzer A Hofstetter B Hollenstein A Riesterer O Vuong V Pruschy M 《Current pharmaceutical design》2007,13(5):519-535
In current applied radiobiology, there exists a tremendous effort in basic and translational research to identify novel treatment modalities combining ionizing radiation with anticancer agents. This is mainly due to the highly improved molecular understanding of intrinsic radioresistance and the profiling of cellular stress responses to irradiation during recent years. Ionizing radiation not only damages DNA but also affects multiple cellular components that induce a multi-layered stress response. The treatment responses can be restricted to the individual cell level but might also be part of an intercellular stress communication network. Both DNA damage-induced signaling (which results in cell cycle arrest and induction of the DNA-repair machinery) and also ionizing radiation-induced signal transduction cascades, which are generated at cellular sites distant from and independent of DNA-damage, represent interesting targets for anticancer treatment modalities to sensitize for ionizing radiation. Due to the lack of molecular knowledge classic radiobiology assembled the cellular and tissue responses into four groups (4 R's of radiotherapy) which describe biological factors influencing the treatment response to fractionated radiotherapy. These classic 4 R's are Repair, Reassortment, Repopulation and Reoxygenation. With the tremendous progress in molecular oncology we now begin to understand theses factors on the molecular level. At the same time this classification may guide modern molecular radiobiologists to identify novel pharmaceuticals and antisignaling agents which can modulate the treatment response to irradiation. In this review we describe current approaches to sensitize tumor cells with novel anticancer agents along the lines of these 4 R's. 相似文献
90.
The dosimetric properties of a novel intracavitary mold applicator for 192Ir high dose rate (HDR) endorectal cancer treatment have been investigated using Monte Carlo (MC) simulations and experimental methods. The 28 cm long applicator has a flexible structure made of silicone rubber for easy passage into cavities with deep-seated tumors. It consists of eight source catheters arranged around a central cavity for shielding insertion, and is compatible for use with an endocavitary balloon. A phase space model of the HDR source has been validated for dose calculations using the GEANT4 MC code. GAFCHROMIC EBT model film was used to measure dose distributions in water around shielded and unshielded applicators with two loading configurations, and to quantify the shielding effect of a balloon injected with an iodine solution (300 mg I/mL). The film calibration procedure was performed in water using an 192Ir HDR source. Ionization chamber measurements in a Lucite phantom show that placing a tungsten rod in the applicator attenuates the dose in the shielded region by up to 85%. Inserting the shielded applicator into a water-filled balloon pushes the neighboring tissues away from the radiation source, and the resulting geometric displacement reduces the dose by up to 53%; another 8% dose reduction can be achieved when the balloon is injected with an iodine solution. All experimental results agree with the GEANT4 calculations within measurement uncertainties. 相似文献