全文获取类型
收费全文 | 4518篇 |
免费 | 234篇 |
国内免费 | 55篇 |
专业分类
耳鼻咽喉 | 43篇 |
儿科学 | 189篇 |
妇产科学 | 55篇 |
基础医学 | 555篇 |
口腔科学 | 40篇 |
临床医学 | 242篇 |
内科学 | 1490篇 |
皮肤病学 | 56篇 |
神经病学 | 356篇 |
特种医学 | 116篇 |
外科学 | 634篇 |
综合类 | 8篇 |
预防医学 | 77篇 |
眼科学 | 89篇 |
药学 | 256篇 |
中国医学 | 3篇 |
肿瘤学 | 598篇 |
出版年
2024年 | 3篇 |
2023年 | 30篇 |
2022年 | 69篇 |
2021年 | 116篇 |
2020年 | 70篇 |
2019年 | 90篇 |
2018年 | 101篇 |
2017年 | 104篇 |
2016年 | 123篇 |
2015年 | 108篇 |
2014年 | 127篇 |
2013年 | 189篇 |
2012年 | 288篇 |
2011年 | 362篇 |
2010年 | 209篇 |
2009年 | 170篇 |
2008年 | 287篇 |
2007年 | 299篇 |
2006年 | 319篇 |
2005年 | 330篇 |
2004年 | 308篇 |
2003年 | 287篇 |
2002年 | 260篇 |
2001年 | 49篇 |
2000年 | 35篇 |
1999年 | 53篇 |
1998年 | 56篇 |
1997年 | 49篇 |
1996年 | 37篇 |
1995年 | 36篇 |
1994年 | 50篇 |
1993年 | 51篇 |
1992年 | 23篇 |
1991年 | 25篇 |
1990年 | 13篇 |
1989年 | 10篇 |
1988年 | 8篇 |
1987年 | 8篇 |
1986年 | 11篇 |
1985年 | 2篇 |
1984年 | 5篇 |
1982年 | 9篇 |
1981年 | 7篇 |
1980年 | 6篇 |
1979年 | 3篇 |
1976年 | 1篇 |
1975年 | 4篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1969年 | 1篇 |
排序方式: 共有4807条查询结果,搜索用时 15 毫秒
11.
Atsushi Hirayama Hiroyuki Miyakawa Toshihiro Suga Tatsuya Nagakawa Takahiro Matsunaga Keiya Okamura Hirokazu Oohashi Tomonori Anpo Takashi Hasegawa 《Digestive endoscopy》2006,18(2):147-150
Recently, a self‐expandable metallic stent has been recognized for treatment of malignant duodenal stenosis. But the complications by stenting are important problems even now. In the present study, we report our new method of duodenal stenting by using of double‐balloon enteroscopy considered safe and effective. 相似文献
12.
Kazuo Kitagawa Masayasu Matsumoto Keisuke Kuwabara Masafumi Tagaya Toshiho Ohtsuki Ryuji Hata Hirokazu Ueda Nobou Handa Kazufumi Kimura Takenobu Kamada 《Brain research》1991,561(2)
We investigated the effects of mild and non-lethal ischemic insult on neuronal death following subsequent lethal ischemic stress in various brain regions, using a gerbil model of bilateral cerebral ischemia. Single 10-min ischemia consistently caused neuronal damage in the hippocampal CA1, CA2, CA3 and CA4, layer III/IV of the cerebral cortex, dorsolateral part of the caudoputamen and ventrolateral part of the thalamus. On the other hand, in double ischemia groups, 2-min ischemic insult 2 days before 10-min ischemia exhibited significant protection in the CA1 and CA3 of the hippocampus, the cerebral cortex, the caudoputamen and the thalamus. Five-min ischemic insult 2 days before 10-min ischemia also showed protective effect in the same areas as those of 2-min ischemia except for the CA1 region of the hippocampus, while 1-min ischemic insult exhibited no protective effect in any brain regions. In the immunoblot analysis, both 2- and 5-min ischemia caused increased synthesis of heat shock protein 72 (HSP 72) in the hippocampus, but 1-min ischemia did not. The present study demonstrated that the ‘ischemic tolerance’ phenomenon was widely found in the brain and also suggested that ischemic treatment severe enough to cause HSP 72 synthesis might be needed for induction of ‘ischemic tolerance’. 相似文献
13.
Kunihiko Sasai Takashi Adachi Kouki Togano Ei Wakabayashi Hiroyuki Ohnari Hirokazu Iida 《The spine journal》2006,6(4):464-467
BACKGROUND CONTEXT: There is no report in the literature of two-level disc herniation in the cervical and thoracic spine presenting with spastic paresis/paralysis exclusively in the bilateral lower extremities. PURPOSE: To identify the clinical characteristics of specific myelopathy resulting from C6-C7 disc herniation through a case with spastic paresis in the lower extremities without upper extremities symptoms due to separate disc herniation in the cervical and thoracic spine, which was surgically removed in two stages. STUDY DESIGN/SETTING: A case report. METHODS: A 48-year-old man developed a gait disturbance as well as weakness and numbness in the lower extremities. Thoracic magnetic resonance imaging (MRI) showed a T11-T12 disc herniation, which was removed under the surgical microscope through a minimally invasive posterior approach. He improved, but 2 months after surgery developed recurrent numbness and spasticity. On this occasion, no evidence of recurrence of the thoracic disc herniation could be identified, but cervical MRI demonstrated a compressed spinal cord at the C6-C7 level. The patient had no neurological findings in the upper extremities. The herniated disc at C6-C7 was removed under the surgical microscope with laminoplasty. RESULTS: The symptoms gradually improved after surgery. At the present time, 2 years and 9 months after the initial operation, the patient had a stable gait and was able to work. CONCLUSIONS: Our experience suggests that in the diagnosis of patients with spastic paresis and sensory disturbances in the lower extremities, spinal cord compression should be explored by imaging studies not only in the thoracic spine but also in the cervical spine, especially at the C6-C7 level, even if the symptoms and abnormal neurological findings are absent in the upper extremities. 相似文献
14.
Video-EEG Analysis of Drop Seizures in Myoclonic Astatic Epilepsy of Early Childhood (Doose Syndrome) 总被引:3,自引:0,他引:3
We studied 36 drop seizures in 5 patients with myoclonic astatic epilepsy of early childhood (MAEE) with simultaneous split-screen video recording and polygraph. Sixteen were falling attacks and 20 were either less severe attacks exhibiting only deep head nodding or seizures equivalent to drop attacks in terms of ictal pattern but recorded in the supine position. All seizures except those that occurred in patients in the supine position showed sudden momentary head dropping or collapse of the whole body downward. Recovery to the preictal position was observed in 0.3-1 s. As a result of carefully repeated observations, the 36 seizures were classified as myoclonic flexor type in 9, myoclonic atonic type in 2, and atonic type, with and without transient preceding symptoms in the remaining 25. The MF seizure was characterized by sudden forward flexion of the head and trunk as well as both arms, which caused the patient to fall. In the myoclonic atonic seizure, patients showed brief myoclonic flexor spasms, immediately followed by atonic falling. The AT seizure showed abrupt atonic falling, with and without transient preceding facial expression change and/or twitching of extremities. The ictal EEGs of all 36 seizures exhibited generalized bilaterally synchronous single or multiple spike(s) and wave discharges. Atonic drop attacks appear to be a common cause of ictal epileptic falling in MAEE. 相似文献
15.
Ivana Kawikova Hirokazu Arakawa Maud Petersson Claes-Gran Lfdahl Bengt-Eric Skoogh Jan Ltvall 《European journal of pharmacology》1995,280(3):293-299
The aim of this study was to evaluate the role of thromboxane A2 in bradykinin-induced airflow obstruction in guinea pig in vivo. Airway insufflation pressure (Pi) was measured to assess airflow obstruction and the thromboxane B2 (a stable metabolite of thromboxane A2) concentration in bronchoalvelolar lavage fluid was determined by radioimmunoassay. The animals were pretreated with propranolol (1 mg/kg i.v.) and suxamethonium (5 mg i.v.) prior to bradykinin administration. Bradykinin instillation into the trachea (300 nmol) induced a Pi increase (47.5 ± 8.3 cm H2O versus 23.8 ± 1.5 in sham) and significant thromboxane B2 release into bronchoalveolar lavage fluid (79 ± 19 pg/ml versus 19 ± 6 in sham). A thromboxane synthase inhibitor (OKY-046, 30 mg/kg i.v.; ((E-E)-3-[p(1H-imidazole-1-yl-methyl) phenyl]-2-propenoic acid hydrochloride mono-hydrate)) or a thromboxane A2 receptor antagonist (ICI192,605, 0.5 mg/kg i.v.; (4-(Z)-6-(2-o-chloro-phenyl-4-o-hydroxyphenyl-1,3-dioxan-cis-5-yl)hexenoic acid)) reduced the Pi increase evoked by bradykinin (38.7 ± 3.8 and 40.6 ± 3.8 cm H2O, respectively). OKY-046 abolished the thromboxane B2 release. A platelet-activating factor receptor antagonist, WEB2086 (1 mg/kg i.v.; (3-[4-(chlorophenyl)-9-methyl-6H-thienol [3,2-f][1,2,4]trizolo-[4,3-a][1,4] diazepin-2-yl]1-4-(4-morpholinyl)-1-propanon) did not significantly affect any measured parameter. We conclude that, in guinea pigs, bradykinin-induced airway effects are associated with a local thromboxane A2 release. 相似文献
16.
Yuka Takakura Hiroyuki Murai Hirokazu Furuya Hirofumi Ochi Jun-ichi Kira 《Clinical neurology》2005,45(5):346-350
A 74-year-old woman suffered from progressive muscle atrophy and weakness of her arms since she was seventy two years old. Before referral to our department, she was diagnosed as having cervical spondylotic myeloradiculopathy and received spinal fusion. Though spinal decompression was successful, muscle weakness of her upper limbs were progressive even after the surgery. On admission, neurological examinations revealed marked atrophy and weakness of her bilateral upper limbs with absent deep tendon reflexes showing man-in-the-barrel syndrome. Her lower extremities had normal muscle strength, but fasciculations were seen in her all four limbs. Electrophysiologically, motor nerve conduction velocity was almost normal but the amplitude was remarkably decreased, conduction block was not detected, and electromyography showed neurogenic patterns on her all extremities. Spinal progressive musclar atrophy (SPMA) accompanied with Sj?gren's syndrome was the likely diagnosis. Because 50 kDa anti-neuronal antibodies were found in her serum, we assumed that anterior horn cells were impaired by an autoimmune mechanism. Thus we treated her with corticosteroid pulse therapy, plasma exchange (PE) and intravenous immunoglobulin infusion therapy (IVIG). Although steroid pulse therapy only had a minimal effect, PE and IVIG promoted a remarkable improvement on her weakness, and the effect lasted for about three months. This is the first case of SPMA with Sj?gren's syndrome which showed good response to PE and IVIG in the early course of the disease. We considered that some SPMA-like motor neuron syndrome accompanied with autoimmune features may require immunomodulating therapies. 相似文献
17.
18.
The distinction between Burkitt lymphoma and diffuse large B-Cell lymphoma with c-myc rearrangement. 总被引:2,自引:0,他引:2
Naoya Nakamura Hirokazu Nakamine Jun-Ichi Tamaru Shigeo Nakamura Tadashi Yoshino Kouichi Ohshima Masafumi Abe 《Modern pathology》2002,15(7):771-776
To compare immunophenotypic and molecular features between Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) with c-myc rearrangements (c-mycR DLBCL), we analyzed 18 cases of B-cell non-Hodgkin's lymphoma with c-mycR that were confirmed by chromosomal and/or Southern blotting analyses. The cases were histologically classified into 10 BLs and five DLBCLs. The remaining three cases could not be classified because of suboptimal quality of the surgical materials. BLs were from five adults and five children, whereas all DLBCLs were from adults. BLs were positive for CD20 (10/10 cases examined), CD10 (9/10), Bcl-2 (1/9), and Bcl-6 (10/10), whereas they were negative for CD3 (0/10) and EBV (0/8), by Epstein-Barr virus (EBV) EBER-1 RNA in situ hybridization. c-MycR DLBCLs were positive for CD20 (5/5), CD10 (2/5), Bcl-2 (3/4), and Bcl-6 (4/4), whereas none of them were positive for CD3 and EBV. A mean of MIB-1 index (MIB-1+ cells/neoplastic cells, %) of BLs (98.1%) was higher than that of c-mycR DLBCLs (66.3%; P <.0001). Somatic mutation of immunoglobulin heavy-chain gene variable region (VH gene) in BLs (four cases) ranged from 0.7 to 4.9% with an average value of 2.3%, whereas those in DLBCLs (three cases) from 8.2 to 32.0% with an average value of 17.0%. It is, therefore, concluded that a growth fraction of nearly 100%, as well as a monotonous proliferation of medium-sized cells and c-myc(R), should be of value in the diagnosis of BL, which is probably different from c-myc(R) DLBCL. In addition, CD10+, Bcl-2-, and low frequency of mutation of the VH gene could be helpful for the histologic distinction of BL from (c-mycR) DLBCL. 相似文献
19.
Transcription factor Ets-1 mediates ischemia- and vascular endothelial growth factor-dependent retinal neovascularization 总被引:10,自引:0,他引:10
下载免费PDF全文
![点击此处可从《The American journal of pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
20.
Hiraoka S Takeuchi N Bian Y Nakahara H Kogo M Dunussi-Joannopoulos K Wolf S Ono S Fujiwara H 《International immunology》2005,17(8):1071-1079
The B7/CD28 co-stimulatory pathway plays a critical role in T cell activation and differentiation. Our previous study demonstrated that administration of B7.2-Ig fusion proteins to tumor-bearing mice elicits IL-4-dependent, CD8+ T cell-mediated tumor regression. Here, we investigated whether B7.2-Ig stimulation of tumor-sensitized CD8+ CTL precursors during in vitro antigen re-sensitization actually results in their differentiation into mature CTLs and if so, whether such a process depends on IL-4 signals. Splenocytes from tumor-sensitized (tumor-bearing or tumor-immunized) mice exhibited low levels of anti-tumor CTL responses upon culturing alone, but induced strikingly enhanced CTL responses when stimulated in vitro with B7.2-Ig fusion proteins. Because CTLs were not generated from normal splenocytes even by B7.2-Ig stimulation, the expression of the B7.2-Ig effect required the in vivo tumor sensitization of CD8+ CTL precursors. Administration of anti-CD4 or anti-CD40 ligand (CD40L) to mice before tumor sensitization resulted in almost complete inhibition of CTL responses generated in the subsequent culture containing B7.2-Ig. In contrast, anti-IL-4 did not influence in vivo tumor sensitization required for CTL induction. However, B7.2-Ig stimulation of tumor-sensitized splenocytes enhanced IL-4 production and neutralization of this IL-4 with anti-IL-4 potently down-regulated CTL responses. These results indicate that B7.2-Ig enhances IL-4-dependent differentiation of anti-tumor CD8+ CTL precursors that can be sensitized in vivo depending on collaboration with CD4+ T cells involving CD40L function. 相似文献