全文获取类型
收费全文 | 18044篇 |
免费 | 809篇 |
国内免费 | 60篇 |
专业分类
耳鼻咽喉 | 238篇 |
儿科学 | 314篇 |
妇产科学 | 240篇 |
基础医学 | 2590篇 |
口腔科学 | 591篇 |
临床医学 | 1074篇 |
内科学 | 4652篇 |
皮肤病学 | 276篇 |
神经病学 | 1185篇 |
特种医学 | 881篇 |
外科学 | 2797篇 |
综合类 | 86篇 |
一般理论 | 1篇 |
预防医学 | 567篇 |
眼科学 | 342篇 |
药学 | 1177篇 |
中国医学 | 41篇 |
肿瘤学 | 1861篇 |
出版年
2023年 | 85篇 |
2022年 | 175篇 |
2021年 | 310篇 |
2020年 | 185篇 |
2019年 | 239篇 |
2018年 | 265篇 |
2017年 | 228篇 |
2016年 | 291篇 |
2015年 | 301篇 |
2014年 | 426篇 |
2013年 | 544篇 |
2012年 | 910篇 |
2011年 | 987篇 |
2010年 | 528篇 |
2009年 | 489篇 |
2008年 | 872篇 |
2007年 | 985篇 |
2006年 | 1018篇 |
2005年 | 985篇 |
2004年 | 948篇 |
2003年 | 947篇 |
2002年 | 924篇 |
2001年 | 490篇 |
2000年 | 531篇 |
1999年 | 491篇 |
1998年 | 288篇 |
1997年 | 224篇 |
1996年 | 186篇 |
1995年 | 151篇 |
1994年 | 145篇 |
1993年 | 158篇 |
1992年 | 370篇 |
1991年 | 352篇 |
1990年 | 302篇 |
1989年 | 279篇 |
1988年 | 266篇 |
1987年 | 247篇 |
1986年 | 199篇 |
1985年 | 188篇 |
1984年 | 152篇 |
1983年 | 129篇 |
1981年 | 65篇 |
1979年 | 81篇 |
1978年 | 68篇 |
1977年 | 64篇 |
1975年 | 78篇 |
1973年 | 64篇 |
1972年 | 69篇 |
1968年 | 75篇 |
1967年 | 74篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
BACKGROUND: Based on epidemiological studies of prevalence, sensitization as well as pollen survey, it is presumed that airborne Japanese cedar pollen (JCP) and cypress (JCyP) have increased progressively for past 40 years. However, because of their large yearly variations, accurate objective and scientific study is required to confirm if it is true or not. METHODS: We analyzed the time trends of JCP and JCy separately in 11 districts throughout Japan where have records of continuous past survey from 1986 to 2005, by regression analysis using net pollen count and their 3 and 5 running means. RESULTS: When significant slope of regression line (regression coefficient) is assumed as p < 0.05 and R2 (coefficient of determination) >0.4, significant increase in airborne pollen was revealed in the use of 5 point running mean (6 districts of total 11 in JCP and 5 in JCyP) but not net count or 3 point running mean because of correction of statistic error due to large yearly variations. This study suggested that our method used for analysis of a recent increase in airborne JCP and JCyP was useful and scientific. 相似文献
33.
34.
Usefulness of magnetic motor evoked potentials in the surgical treatment of hemiplegic patients with intractable epilepsy. 总被引:2,自引:0,他引:2
Tohru Kamida Hiroshi Baba Kenji Ono Masato Yonekura Minoru Fujiki Hidenori Kobayashi 《Seizure》2003,12(6):373-378
Five hemiplegic patients with intractable epilepsy were studied with transcranial magnetic stimulation (TMS) before and after various surgical treatments. These patients had unilateral widespread cerebral lesions acquired at various times, including congenital, infantile and childhood injury. Motor evoked potentials (MEPs) of the abductor pollicis brevis (APB) muscles were simultaneously recorded on both sides following TMS of the motor cortex in the respective hemisphere using a figure-8 or circular coil. In all patients with congenital disease, the abolition of motor function in the affected hemisphere was estimated by magnetic MEPs, and the hemiplegia did not deteriorate after functional hemispherectomy (HS) was performed in two of them. In two patients with acquired disease, HS was not performed because it was shown by magnetic maps that the motor function in the affected hemisphere remained. Furthermore, it was shown by electric MEPs using subdural electrodes that a patient who had had encephalitis in early childhood had a reorganised motor area in the parietal cortex of the affected hemisphere. The present findings indicate that magnetic MEPs are a very useful non-invasive method of assessing whether the motor area in the affected hemisphere can be resected in hemiplegic patients with intractable epilepsy. 相似文献
35.
Ryosuke Murakami Torn Otani Katsumi Nakanishi Yoshiyuki Fudemoto Hideki Ishikawa Tomohiko Hiyama Hideaki Tsukuma Isaburo Fujimoto Nobuo Miki Akira Oshima 《Cancer science》1992,83(2):141-145
In order to estimate the diagnostic validity of chemical fecal occult blood tests, i.e. orthotolidine (Shionogi A) and guajac (Shionogi B) slides for detecting cancers of the esophagus, stomach and colorectum, the authors followed up all the examinees (n=3,449) of comprehensive medical check-ups at the Center for Adult Diseases, Osaka, by means of record linkage to the Osaka Cancer Registry's files. Then, diagnostic validity was calculated based on the results of two years' follow-up. Sensitivity for the respective cancers was 20.0%, 11.8% and 62.5% for Shionogi A, and 20.0%, 5.9% and 43.8% for Shionogi B slides. Likelihood ratio for the respective cancers was 1.4, 0.8 and 4.5 for Shionogi A, and 3.3, 1.0 and 7.5 for Shionogi B. Specificity was analogous among the three cancer sites, being 86% for Shionogi A and 94% for Shionogi B. These results suggest that the diagnostic validity of chemical occult blood tests for detecting cancers of the esophagus and the stomach is very poor, and therefore imply that close examinations of these sites for screening positives is unnecessary in mass screenings for colorectal cancer. 相似文献
36.
Fumio Yamauchi Yoshihiro Takebayashi Takaya Abe Toshinari Muramatsu Rika Murakami Masaki Ohtsuka Masayuki Endoh Yasuo Nomoto Hideto Sakai Miho Hida 《Clinical and experimental nephrology》1997,1(3):243-246
A 52-year-old woman who had had 6 months of chemotherapy using mitomycin C and cisplatin for cervical cancer presented with
hemolytic uremic syndrome. Conventional plasmapheresis using whole-plasma fraction was ineffective. However, plasmapheresis
using the cryosupernatant fraction dramatically improved symptoms of hemolytic anemia and thrombocytopenia in this case. The
activity of factor VIII in the cryosupernatant fraction of plasma as a replacement fluid decreased after removal of cryoprecipitate,
indicating effective removal of von Willebrand factor. The pathogenesis of her hemolytic uremic syndrome may have been associated
with von Willebrand factor multimers contained in the cryoprecipitate of plasma. Similar use of the cryosupernatant fraction
of plasma could not be found in other reports of cases of hemolytic uremic syndrome. Plasmapheresis using the cryosupernatant
fraction of plasma may improve refractory hemolytic uremic syndrome. 相似文献
37.
Hiroyuki Yamashita MD Katsuhiko Kawakami Eiichirou Murakami Syoji Kuroki 《Surgery today》1990,20(2):229-233
A rare case of primary linitis plastica carcinoma of the colon seen in a 44 year old Japanese man is described herein. The
patient had a complete obstruction of the descending colon and was treated with a loop colostomy followed shortly afterward
by a left hemicolectomy. At the time of the second operation, the entire thickness of the colonic wall was found to be infiltrated
by cancer cells, however, the other intraabdominal organs were free of cancerous involvement. The histopathological diagnosis
made at this time was primary linitis plastica carcinoma of the descending colon. Nine months later, the patient developed
an intestinal obstruction and relaparotomy revealed diffuse peritoneal dissemination. Two years after the first operation,
upper GI films and a gastrofiberscopic examination revealed gastric involvement. The patient died 28 months after his initial
operation, and autopsy revealed widespread metastases in the peritoneal surface, paraaortic lymph nodes, small intestine,
remaining colon and stomach. 相似文献
38.
C Yajima N Sugai K Hanaoka K Numata K Yamamoto Y Kushida S Murakami H Yamamura 《Masui. The Japanese journal of anesthesiology》1990,39(7):882-889
The pharmacokinetics of pipecuronium bromide was studied in 9 male patients (ASA class 1-2, 20-65 years of age). Following a single intravenous dose of pipecuronium 0.08 mg.kg-1, plasma levels were measured by capillary gas chromatography. Plasma concentration-time curves were evaluated by fitting the data to a bi-exponential equation. The pharmacokinetic parameters of pipecuronium were compared with those of pancuronium (0.08 mg.kg-1) and vecuronium (0.08 mg.kg-1) previously obtained under the same anesthesia (66% N2O, 33% O2 and 1% halothane). With pipecuronium, following pharmacokinetic parameters were obtained; distribution half-life; T1/2 alpha = 3.9 +/- 0.7 min (mean +/- SEM), elimination half-life; T1/2 beta = 102 +/- 12 min, volume of the central compartment; V1 = 95 +/- 13 ml.kg-1, volume of distribution at steady state; Vdss = 264 +/- 41 ml.kg-1, clearance; Cl = 1.8 +/- 0.2 ml.min-1.kg-1. Microconstants of two-compartment open models (k12, k21, k10) were also calculated. Using Mann-Whitney's U-test, these parameters of pipecuronium were compared with those of pancuronium (n = 3) and vecuronium (n = 4). V1 and Vdss of pipecuronium were significantly larger than those of pancuronium (V1; 38 +/- 12 ml.kg-1 and Vdss; 120 +/- 4 ml.kg-1) (both P less than 0.10). Reflecting the larger central volume of pipecuronium, pipecuronium tended to have a larger clearance than that of pancuroniumu (Cl; 1.1 +/- 0.2 ml.min-1.kg-1).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
39.
Akihiko Usui Fumihiko Murakami Hideki Ooshima Yasuhiro Tomita Katsuhiko Yoshida Michiaki Hibi Mitsuo Kawamura Mitsuya Muras 《Artificial organs》1997,21(7):772-778
Abstract: Cardiopulmonary support (CPS) requires durability of the oxygenator. The life span of the oxygenator is affected by various clinical factors, including patient condition, perfusion condition, and equipment usage. Predictors for the durability of oxygenators were evaluated clinically in this study. Thirty-two patients, who had undergone CPS during the last 3 years in our institute were assigned to this study. Fifty oxygenators had been used (Capiox SX in 19, CB Maxima in 23, and AL-6000 in 8). Significant predictors for the durability of oxygenators were evaluated by nonparametric survival analysis and proportional hazards regression analysis. Univariate regression analysis revealed 6 significant predictors for the life span of oxygenators. These were the oxygenator type, type of centrifugal pump, acidosis with blood pH less than 7.35, base excess less than -5, blood glutamic-oxaloacetic transaminase (GOT) levels greater than 1,000 IU, and blood lactate dehydrogenase (LDH) levels greater than 3,000 IU. After multivariate analysis, there remained only 2 significant predictors. An oxygenator used with a noncoated CPS system (Capiox SX with Capiox EBS) proved to have a significantly shorter life span than one used with a heparin-coated system (CB Maxima or AL-6000 with CB BP-80) (hazards ratio, 3.588, p = 0.0065). Patient conditions, which revealed acidosis with less than -5 of base excess, significantly shortened the life of the oxygenator (hazards ratio, 3.595, p = 0.0188). 相似文献
40.
Kazuya Tamai MD PhD Minoru Yamato MD PhD 《Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.]》1997,6(6):534
We studied 16 patients (18 shoulders) with frozen shoulders, 8 patients with subacromial impingement syndrome, and 3 healthy volunteers with dynamic magnetic resonance imaging enhanced with gadolinium diethylenetriaminepentaacetic acid. After intravenous contrast was administered, gradient-recalled echo images were obtained in the oblique coronal plane every 11 to 13 seconds for a total period of 4 to 5 minutes. The signal intensity was measured at the periphery of the glenohumeral joint and in the subacromial bursa. The coefficient of enhancement (percent signal increase per second) in the frozen shoulders was 1.33±0.43 (mean ± SD) for the glenohumeral joint and 0.89±0.47 for the subacromial bursa. These values were far greater than those in subacromial impingement syndrome or in the control group, indicating increased blood flow to the synovium in the frozen shoulders. No previous reports have shown a clinical measure related to the pathophysiology of this disease. 相似文献