全文获取类型
收费全文 | 19710篇 |
免费 | 973篇 |
国内免费 | 118篇 |
专业分类
耳鼻咽喉 | 121篇 |
儿科学 | 364篇 |
妇产科学 | 178篇 |
基础医学 | 2561篇 |
口腔科学 | 268篇 |
临床医学 | 1292篇 |
内科学 | 5035篇 |
皮肤病学 | 326篇 |
神经病学 | 1275篇 |
特种医学 | 799篇 |
外科学 | 3766篇 |
综合类 | 52篇 |
预防医学 | 545篇 |
眼科学 | 470篇 |
药学 | 1533篇 |
中国医学 | 58篇 |
肿瘤学 | 2158篇 |
出版年
2023年 | 101篇 |
2022年 | 230篇 |
2021年 | 394篇 |
2020年 | 205篇 |
2019年 | 290篇 |
2018年 | 383篇 |
2017年 | 297篇 |
2016年 | 359篇 |
2015年 | 431篇 |
2014年 | 529篇 |
2013年 | 612篇 |
2012年 | 975篇 |
2011年 | 1107篇 |
2010年 | 611篇 |
2009年 | 492篇 |
2008年 | 988篇 |
2007年 | 1055篇 |
2006年 | 1053篇 |
2005年 | 1092篇 |
2004年 | 1110篇 |
2003年 | 1066篇 |
2002年 | 1094篇 |
2001年 | 411篇 |
2000年 | 446篇 |
1999年 | 468篇 |
1998年 | 243篇 |
1997年 | 194篇 |
1996年 | 207篇 |
1995年 | 166篇 |
1994年 | 175篇 |
1993年 | 185篇 |
1992年 | 390篇 |
1991年 | 365篇 |
1990年 | 308篇 |
1989年 | 348篇 |
1988年 | 301篇 |
1987年 | 282篇 |
1986年 | 262篇 |
1985年 | 249篇 |
1984年 | 166篇 |
1983年 | 138篇 |
1982年 | 66篇 |
1979年 | 126篇 |
1978年 | 94篇 |
1977年 | 63篇 |
1975年 | 67篇 |
1974年 | 62篇 |
1973年 | 53篇 |
1972年 | 52篇 |
1969年 | 55篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Jun Maeda Mitsunori Ohta Hirohisa Hirabayashi Hikaru Matsuda 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(4):196-198
We present a case of lung cancer that showed false positive accumulation in an 18F fluorodeoxyglucose positron emission tomography (FDG-PET) scan following induction chemotherapy for suspected metastasis
and progression of malignancy. A 66-year-old man was diagnosed with squamous cell carcinoma in the lung, classified as clinical
stage IIIA (T2N2M0), and underwent induction chemotherapy. An FDG-PET scan prior to chemotherapy demonstrated accumulation
only in the tumor, whereas following treatment it revealed a strong accumulation not only in the tumor, but also in the supraclavicular
lymph nodes, which indicated lymph node metastasis. The patient underwent a biopsy of the right supraclavicular lymph node
and mediastinoscopy, after which all dissected lymph nodes showed sarcoid reactions and no tumor cells were found pathologically.
We concluded that when evaluating the effect of induction chemotherapy for malignancy, a sarcoid reaction might lead to the
false positive accumulation of FDG. 相似文献
82.
Takashi Ishimori Satoru Nakano Yasutane Mori Reiko Seo Taro Togami Tetsuya Masada Toshiaki Kusuhara Motoomi Ohkawa Seigo Nagao Yuichi Yamashita Satoshi Sugiura 《Magnetic resonance in medical sciences》2007,6(4):225-229
PURPOSE: We assessed the feasibility of utilizing three-dimensional (3D) phase sensitive inversion recovery (IR) images for preoperatively determining deep brain stimulator position. METHODS: We measured geometric distortion with a grid phantom and evaluated images of 3 volunteers to determine optimum imaging parameters for 3D phase sensitive IR. RESULTS: Geometric distortion measured less than 1.0%. Respective inversion and recovery times, which provided high T(1) contrast between the subthalamic nucleus and adjacent tissue, were 200 and 4000 ms. In studies of 3 volunteers and 2 patients, the subthalamic nucleus was clearly depicted in 3D phase sensitive IR images. The measured coordinates of the subthalamic nucleus agreed well with those calculated by conventional estimation from midpoint of the anterior and posterior commissure. CONCLUSION: Three-dimensional phase sensitive inversion recovery was useful in visualizing the subthalamic nucleus for effective deep brain stimulation. 相似文献
83.
Kenji Yamao Atsushi Irisawa Hiroyuki Inoue Koji Matsuda Mitsuhiro Kida Shomei Ryozawa Yoshiki Hirooka Teruo Kozu 《Digestive endoscopy》2007,19(Z1):S180-S205
Standard imaging techniques using a curved linear array echoendocope are summarized to facilitate the attainment of expertise in endoscopic ultrasonography and endoscopic ultrasound‐guided fine needle aspiration, and to promote the widespread use of this diagnostic and therapeutic tool. Typical images of the mediastinal organs, the bilio‐pancreatic systems and neighboring organs by scanning from the esophagus, stomach, duodenal bulb, and descending portion of the duodenum, are shown in a sequential manner. The basic techniques of endoscopic ultrasound‐guided fine needle aspiration are also presented. 相似文献
84.
Wakana Goto Hidehiro Oku Takashi Okuno Tetsuya Sugiyama Tsunehiko Ikeda 《Journal of ocular pharmacology and therapeutics》2003,19(1):63-73
We investigated whether topical instillation of an alpha(1)-adrenergic blocker would improve an insufficient blood supply in the optic nerve head (ONH) and visual function, in rabbits. The effect of systemic NOS inhibition on visual-evoked potentials (VEPs) and hemodynamics in ONH were determined. VEPs were recorded before and every 15 min during a 120-min observation period after an intravenous injection of 50 mg/kg N(G)-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase (NOS) inhibitor. Capillary blood flow in ONH was evaluated by the laser speckle method throughout the same period. Then, we investigated the effect of topical instillation of a recently developed alpha(1) adrenergic blocker, bunazosin hydrochloride (0.01%), 60 min prior to the intravenous L-NAME (50 mg/kg) on the changes by NOS inhibition. The VEP amplitudes were reduced by L-NAME (10, 20, and 50 mg/kg) in a dose-dependent manner, while the VEP implicit time was unchanged, and no significant changes were detected in the electroretinogram. The reductions in ONH capillary blood flow and VEP amplitudes caused by L-NAME (50 mg/kg) were significantly suppressed by an instillation of bunazosin hydrochloride. These results indicate that blocking alpha(1)-adrenergic receptors may ameliorate the impairments in blood flow and retinal function caused by NOS inhibition. The enhancement of basal vascular tone due to deprivation of continuous NO production may be diminished by this alpha(1)-adrenergic blocker. 相似文献
85.
N Yoshimura T Asada H Matsuda H Nohara T Higami M Nishiwaki N Mukohara M Chibana K Ogawa 《Kyobu geka. The Japanese journal of thoracic surgery》1990,43(2):157-159
A 17-year-old male patient with Marfan syndrome was admitted due to recurrent bilateral pneumothorax which had recurred totally 11 times during the past 3 years. For the treatment of obstinately continuing right pneumothorax resection of bullae in combination with pleuropexy using OK 432 was effective. Two months thereafter Bentall operation with a composite graft consisting of a woven Dacron tube and a Bj?rk-Shiley 27 mm aortic valve prosthesis was performed for his anuloartic ectasia. Left pneumothorax recurred 2 weeks after Bentall operation. But it was treated successfully with OK 432 injection into the left pleural cavity. Now, he is doing well as a student. 相似文献
86.
M Kubo T Odani S Nakamura S Tokumaru H Matsuda 《Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan》1992,112(7):489-495
The antitumor activity of kefir (YK-1), a fermented milk product in Caucasus, was investigated. YK-1 at oral doses of 100 or 500 mg/kg inhibited the proliferation of solid tumor of Ehrlich ascites carcinoma transplanted subcutaneously in mice. YK-1 did not show an inhibitory effect on the ear swelling induced contact dermatitis caused by picryl chloride (PC-CD). However, YK-1 inhibited the immunosuppression in Ehrlich carcinoma-bearing mice and with the frozen and dried ascites of the tumor-bearing mice containing immunosuppressive substances (EC-sup) in PC-CD-induced mice. And also, YK-1 activated the immunosuppressive activity of spleen cells of mouse treated with EC-sup. These results suggest that YK-1 may have antitumor activity against Ehrlich carcinoma and activate the immunosuppression with it. 相似文献
87.
Hajime Kazamatsuri M.D. Tetsuya Hirose M.D. Osamu Kanno M.D. Nobumasa Kato M.D. Hiromoto Yasuda 《Psychiatry and clinical neurosciences》1994,48(4):869-879
Abstract: Two autopsied female sibling cases of sudanophilic leukodystrophy are reported. Case A and case B were the second and third of seven siblings, and a sister and a brother died from severe progressive neurological disease with similar symptoms. Consanguineous marriages were noted in the family of both cases through the past three generations. Case A gradually developed intellectual deterioration and tetraplegia at the age of 29, progressed to akinetic mutism within one year and thereafter survived for 14 years. Neuropathologically, a severe atrophy and degeneration were noted in the white matter of the whole cerebrum, sparing the subcortical U-fibers. Myelin and axons were severely damaged with peripheral astrocytic gliosis. Case B developed similar clinical symptoms at the age of 20 and survived for 7 years in the state of akinetic mutism. Similar postmortem findings as those of case A were found in the white matter of the cerebrum with formation of sudanophilic breakdown products and with thick fibrillary gliosis. The pyramidal tract was completely degenerated. There was no accumulation of abnormal lipid in the brains of both cases. 相似文献
88.
89.
Yasunori Utsunomiya Toshiyuki Imasawa Aya Abe Keita Hirano Tetsuya Kawamura Ryuji Nagasawa Tetsuya Mitarai Naoki Maruyama Osamu Sakai 《Clinical and experimental nephrology》1997,1(2):83-91
Background The purpose of this study was to examine the effects of bacterial suporantigens, which can derange the immune response and
contribute to the renal lesions of immunoglobulin A (lgA) nephropathy.
Methods Twenty-five micrograms of a bacterial superantigen, staphylococcal enterotoxin B (SEB), was injected into IgA nephropathy-prone
ddY mice intrathymically when they reached 6 weeks of age. Evaluation included measurement of albumin excretion in urine,
immunoglobulin concentration, and lymphokine production in vitro, as well as analysis of T-cell receptor expression in splenic
T-cell subsets and examination of renal histology by light and fluorescence microscopy.
Results At 40 weeks of age, the serum level of IgA in these mice was substantially increased and the number of Vβ8+ CD4+splenic T-cells was significantly decreased compared with measurements in untreated controls. Both control and SEB-treated
mice excreted less than 30 μg/mL of urinary albumin. In mice given SEB, the amount of interleukin 2 (IL-2) and tumor necrosis
factor-α (T helper 1 [Th1]-type cytokines) produced by the in vitro-stimulated lymphocytes significantly decreased. whereas
that of interleukin 4 (IL-4) and interleukin 6 (IL-6) (Th2-type cytokines) markedly increased compared with measurements in
control mice. At 40 weeks of age, mice given SEB showed marked glomerular hypercellularity and enhanced glomerular C3 deposition
by renal histology, compared with control mice.
Conclusion These results suggest that bacterial superantigen SEB may modify glomerular lesions through activating Th2 cells, while inducing
deletion of Th1 cells in this experimental model. 相似文献
90.