全文获取类型
收费全文 | 19370篇 |
免费 | 909篇 |
国内免费 | 143篇 |
专业分类
耳鼻咽喉 | 201篇 |
儿科学 | 388篇 |
妇产科学 | 156篇 |
基础医学 | 2624篇 |
口腔科学 | 449篇 |
临床医学 | 1248篇 |
内科学 | 5044篇 |
皮肤病学 | 372篇 |
神经病学 | 1771篇 |
特种医学 | 730篇 |
外科学 | 3094篇 |
综合类 | 83篇 |
预防医学 | 545篇 |
眼科学 | 429篇 |
药学 | 1206篇 |
中国医学 | 45篇 |
肿瘤学 | 2037篇 |
出版年
2023年 | 132篇 |
2022年 | 246篇 |
2021年 | 433篇 |
2020年 | 223篇 |
2019年 | 350篇 |
2018年 | 440篇 |
2017年 | 361篇 |
2016年 | 452篇 |
2015年 | 465篇 |
2014年 | 578篇 |
2013年 | 726篇 |
2012年 | 1219篇 |
2011年 | 1374篇 |
2010年 | 739篇 |
2009年 | 619篇 |
2008年 | 1189篇 |
2007年 | 1338篇 |
2006年 | 1256篇 |
2005年 | 1386篇 |
2004年 | 1318篇 |
2003年 | 1304篇 |
2002年 | 1215篇 |
2001年 | 232篇 |
2000年 | 198篇 |
1999年 | 249篇 |
1998年 | 285篇 |
1997年 | 220篇 |
1996年 | 189篇 |
1995年 | 193篇 |
1994年 | 150篇 |
1993年 | 142篇 |
1992年 | 124篇 |
1991年 | 129篇 |
1990年 | 105篇 |
1989年 | 95篇 |
1988年 | 90篇 |
1987年 | 67篇 |
1986年 | 75篇 |
1985年 | 60篇 |
1984年 | 57篇 |
1983年 | 43篇 |
1982年 | 40篇 |
1981年 | 42篇 |
1980年 | 38篇 |
1979年 | 39篇 |
1978年 | 27篇 |
1976年 | 18篇 |
1975年 | 20篇 |
1974年 | 13篇 |
1969年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 12 毫秒
11.
Hisao Komatsu Junko Nogaya Masaaki Ueki Satoshi Yokono Kenji Ogli 《Clinical and experimental pharmacology & physiology》1994,21(6):495-499
1. We previously reported that volatile anaesthetics produce incidences of a transient opisthotonus in mice, a sign of CNS stimulation. This study was performed to investigate mechanisms by which enflurane-induced opisthotonus (EIO) occurs. 2. The effects of pretreatment of N-methyl-d-aspartate (NMDA) antagonists dizocilpine (MK-801; DIZ) and ketamine (KET), GABAA antagonists picrotoxin (PIC), pentylenetetrazol (PTZ) and glycine antagonist strychnine (STR) on the incidence of EIO were determined. Prior to exposure to 2.0% enflurane in air, male ddN mice were given intraperitoneal injections of 0.2 mL saline (control), 0.5–5.0 mg/kg DIZ, 20–80 mg/kg KET, 2.9 mg/kg PIC, 40.0 mg/kg PTZ and 0.75 mg/kg STR. After the injection, the behavioural state of the mice was observed for 20 min (the pre-enflurane period). During the exposure to enflurane the time for immobilization, that is, anaesthetic induction time (IT), and the incidence of EIO were measured. 3. Dizocilpine (1.0–5.0 mg/kg) and KET (80 mg/kg) significantly (P<0.01) reduced both the incidence of EIO and IT in a dose-dependent manner. During the pre-enflurane period DIZ produced incidences (5–40%) of transient seizures in a dose-dependent manner, while KET did not induce them at all. The two GABAa antagonists had no detectable effect on the EIO. Strychnine significantly enhanced the EIO. These CNS stimulants resulted in a 3–10% incidence of transient seizure and/or opisthotonus during the pre-enflurane period, but there was no correlation between DIZ-induced seizure and EIO. 4. These results suggest that the EIO is mediated by the NMDA and the STR-sensitive glycine receptors, but not the GABAA receptor. We speculate that DIZ acts on the NMDA-receptor and/or disrupts the balance between the inhibitory and the excitatory systems. 相似文献
12.
Yoshitaka Hirooka Yoshikuni Kimura Masatsugu Nozoe Yoji Sagara Koji Ito Kenji Sunagawa 《Hypertension research》2006,29(1):49-56
Amlodipine is a dihydropyridine calcium channel blocker that is widely used for the treatment of hypertensive patients and has an antioxidant effect on vessels in vitro. The aim of the present study was to examine whether treatment with amlodipine reduced oxidative stress in the brains of stroke-prone spontaneously hypertensive rats (SHRSP). The animals received amlodipine, nicardipine or hydralazine for 30 days in their drinking water. Levels of thiobarbituric acid-reactive substances (TBARS) in the brain (cortex, cerebellum, hypothalamus, and brainstem) were measured before and after each treatment. Systolic blood pressure decreased to similar levels in the amlodipine-, nicardipine-, and hydralazine-treated groups. Urinary norepinephrine excretion was significantly reduced in SHRSP after treatment with amlodipine, but not with nicardipine or hydralazine. Levels of TBARS in the cortex, cerebellum, hypothalamus, and brainstem were significantly higher in SHRSP than in Wistar-Kyoto rats (WKY), and were reduced in amlodipine-treated, but not in nicardipine- or hydralazine-treated, SHRSP. Electron spin resonance spectroscopy revealed increased levels of reactive oxygen species in the brains of SHRSP, which were reduced by treatment with amlodipine. Intracisternal infusion of amlodipine also reduced systolic blood pressure, urinary norepinephrine excretion, and the levels of TBARS in the brain. These results suggested that oxidative stress in the brain was enhanced in SHRSP compared with WKY rats. In addition, antihypertensive treatment with amlodipine reduced oxidative stress in all areas of the brain examined and decreased blood pressure without a reflex increase in sympathetic nerve activity in SHRSP. 相似文献
13.
Toyohiro Kagawa Fumiko Fukunari Tomoko Shiraishi Miwako Yamasaki Takahiro Ichihara Yuka Kihara Ryousuke Zeze Kentaro Nogami Kenji Yuasa 《Oral Radiology》2006,22(2):47-51
Objectives To develop a simple image viewer that utilizes image files in general-purpose formats that are written from the original 3DX
volume data.
Methods We used FLASH MX2004 for Macintosh to develop a simple image viewer. In developing the software for the simple image viewer,
we decided that the viewer should provide the following features: (1) be available to both Windows OS and Mac OS, (2) allow
interlocking of the 3D images, (3) display image enlargement, and (4) allow distance measurements. The accuracy of the distance
measurements was evaluated.
Results The procedure was as follows: (1) write 3D images in jpeg format to a folder on i-VIEW; (2) place the folder containing the
3D images into the directory of the simple image viewer software on a PC; (3) start the software and open the window to input
the folder name containing the 3D images; and (4) display the 3D images. Our viewer had features such as image enlargement,
interlocking 3D images, drawing, and distance measurements. No significant differences were shown between the measurements
made by our simple viewer and the actual values of the images in any direction.
Conclusions Our image-viewing software for 3DX is beneficial for clinical use. 相似文献
14.
Kenji Tsukada Shigeru Kobayashi Tatsuya Gotoh Naoki Asakage Masayuki Sekine Morio Sasaki Eiji Miyazaki Takahisa Suzuki Toshio Yamada Shu Hirai Shigetaka Yamazaki 《Digestive endoscopy》2006,18(1):55-58
A case of early gastric carcinoma accompanied by Dieulafoy ulcer is presented. The patient, a 26‐year‐old female, visited our emergency room with chief complaints of massive hematemesis and tarry stool. The initial endoscopic examination revealed a superficial depressed lesion with a faded color accompanied by a tiny ulcer with converging folds at the anterior wall of the middle gastric body. Although no active bleeding vessel was found at that time, the patient was admitted to our hospital for further check‐ups and treatment. On the 6th hospital day, she developed massive hematemesis resulting in shock. Urgent endoscopy, this time, disclosed an exposed bleeding vessel at the small ulcer floor previously mentioned, and endoscopic hemostasis was achieved. Since, however, a biopsy at initial examination from the surrounding depressed area proved carcinoma, a partial distal gastrectomy was subsequently carried out. Histological examination of the resected specimen confirmed the diagnosis of carcinoma limited to the mucosa and submucosa along with findings consistent with Dieulafoy ulcer. This is a rare case of combination of early cancer and Dieulafoy ulcer particularly in such a young patient. A review of the literature is also presented. 相似文献
15.
Ryo Hattori MD Tateki Kubo MD Kenji Yano MD PhD Atsushi Tanemura MD Yuji Yamaguchi MD PhD Satoshi Itami MD PhD Ko Hosokawa MD PhD 《Dermatologic surgery》2003,29(10):1071-1072
BACKGROUND: Nevus lipomatosus cutaneous superficialis (NLCS) is a relatively rare condition. Although NLCS can affect any region of the entire body, no case of NLCS in the clitoris has ever been reported. OBJECTIVE: To report a case of NLCS of the clitoris that presented manifestations that were similar to female pseudohermaphrodism. METHODS: This is a case report and review of the literature. RESULTS: A congenital, soft, skin-colored lesion of the clitoris in a 1-year-old girl resembled female pseudohermaphrodism. It was resected, and the histologic diagnosis was NLCS. Postoperatively, there was no subsequent change in the lesion during the 3-year follow-up period. CONCLUSION: We reported a case of congenital solitary NLCS of the clitoris. Although NLCS might be a relatively rare condition, we should consider it in the differential diagnosis of female pseudohermaphrodism. 相似文献
16.
Tetsuhiko Nagao Seizo Sadoshima Takao Ishitsuka Kenji Kusuda Osamu Shiokawa Setsuro Lbayashi Masatoshi Fujishima 《Clinical and experimental pharmacology & physiology》1992,19(7):489-493
1. The effects of acute bilateral superior cervical ganglionectomy on cerebral blood flow and metabolism were investigated in stroke-prone spontaneously hypertensive rats (SHRsp), before and during cerebral ischaemia. 2. The resting cerebral blood flow was comparable between the control and denervated animals. 3. There was no significant difference in cerebral blood flow or concentration of tissue energy metabolites (adenosine triphosphate [ATP], lactate and pyruvate) between the sham-operated control and denervated animals during ischaemia. 4. The results suggest that sympathetic innervation of cerebral vessels originating from superior cervical ganglia may not play a major role in the progression of cerebral ischaemia in SHRsp. 相似文献
17.
Makoto Kamada Kenji Ohsaka Susumu Nagamine Hidemitsu Kakihata 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2003,51(10):552-556
Acute aortic dissection complicated with acute myocardial infarction (AMI) is the most fatal situation. We experienced the
successful treatment for acute type A aortic dissection complicated with inferior AMI following aortic valve replacement (AVR).
A 60-year-old man had had AVR for aortic regurgitation. Sixteen months after the AVR, he had a sudden onset of severe chest
pain with complete atrioventricular block. Immediately, temporary pacing and cardiac catheterization were conducted, showing
the occlusion of the right coronary artery due to acute type A aortic dissection. On his way to our hospital, direct current
shock was conducted 3 times for ventricular fibrillation. We replaced the ascending aorta combined with coronary artery bypass
grafting and the postoperative course was uneventful. The key to treat acute aortic dissection complicated with AMI is early
accurate diagnosis, prompt temporary pacing for bradycardia, defibrillation for lethal arrhythmia and insertion of a perfusion
catheter if possible. These preoperative hemodynamic stabilization gives us the chance to save these patients. 相似文献
18.
Kenji Yoshimi Masatoshi Takeda Tsuyoshi Nishimura Takashi Kudo Yu Nakamura Kunitoshi Tada Nobuyoshi Iwata 《Brain research》1991,560(1-2):149-158
Changes in MAP2 and clathrin immunoreactivity were studied in gerbil hippocampus after transient cerebral ischemia. MAP2 immuno-reactivity decreased significantly by 1 h in the subiculum-CA1 and CA2 areas which correspond to reactive change, while no decrease was observed in CA1 until day 4. Before the initiation of delayed neuronal death, MAP2 immunoreactivity was not changed in CA1. On the other hand clathrin immunoreactivity increased in the pyramidal cell layer of CA1 by 3 h after ischemia and remained high for 2 days. Clathrin immunoreactivity in the pyramidal cell layer of CA1 diminished after delayed neuronal death. The transient change of clathrin was noted especially in CA1 in the period prior to delayed neuronal death. These results imply an abnormal change in clathrin turnover after ischemia, which may participate in the pathogenesis of delayed neuronal death. 相似文献
19.
Hideyuki Iwai Ryuji Koike Jun Ogawa Takahiko Sugihara Hiroyuki Hagiyama Kenji Nagasaka Yoshinori Nonomura Junko Nishio Toshihiro Nanki Rieko Tsubata Hitoshi Kohsaka Tetsuo Kubota Nobuyuki Miyasaka 《Nihon Rinshō Men'eki Gakkai kaishi》2002,25(3):270-276
A 36-year-old man was admitted to a hospital with complaints of fever, polyarthralgia and dyspnea. Erythema was observed on his face, extensor surface of the fingers and extremities, and a chest X-ray revealed massive bilateral pleural effusion. He had no sign of myopathy at this point. Pleural fluid was proved to be exudative and contained extremely high levels of hyaluronic acid. He was also complicated with interstitial pneumonitis and was given a pulse therapy with methyl prednisolone followed by daily administration of 55 mg prednisolone (PSL). Twenty days after the commencement of the therapy, pleural effusion decreased but muscle weakness gradually appeared, accompanied by elevation of myogenic enzymes. Myogenic changes on electromyogram, and irregularity of the muscle fibers with slight inflammatory cell infiltrates in a biopsy specimen were demonstrated. He was transferred to our hospital, and a diagnosis of dermatomyositis was made. Later, pleural effusion waxed and waned depending on the dosage of PSL, but no other causative disorder was demonstrated by extensive examinations. This case indicates that the pleuritis could be one of the vasculitic manifestations of dermatomyositis. 相似文献
20.
Haruo Nagayama Kounosuke Tsuchiyama Kenji Yamada Jotaro Akiyoshi 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(6):735-744
1. In our series of experiments the role of serotonin in human depression was studied by using animal models of depression.
2. The results of these studies support the hypothesis that some types of human depression may be primarily due to an excessive transmission of serotonin at the synapse. 相似文献