全文获取类型
收费全文 | 8641篇 |
免费 | 427篇 |
国内免费 | 48篇 |
专业分类
耳鼻咽喉 | 117篇 |
儿科学 | 195篇 |
妇产科学 | 73篇 |
基础医学 | 952篇 |
口腔科学 | 288篇 |
临床医学 | 532篇 |
内科学 | 2103篇 |
皮肤病学 | 168篇 |
神经病学 | 666篇 |
特种医学 | 264篇 |
外科学 | 1688篇 |
综合类 | 26篇 |
一般理论 | 1篇 |
预防医学 | 191篇 |
眼科学 | 141篇 |
药学 | 498篇 |
中国医学 | 15篇 |
肿瘤学 | 1198篇 |
出版年
2023年 | 60篇 |
2022年 | 131篇 |
2021年 | 223篇 |
2020年 | 126篇 |
2019年 | 166篇 |
2018年 | 189篇 |
2017年 | 150篇 |
2016年 | 201篇 |
2015年 | 176篇 |
2014年 | 260篇 |
2013年 | 289篇 |
2012年 | 437篇 |
2011年 | 471篇 |
2010年 | 306篇 |
2009年 | 240篇 |
2008年 | 391篇 |
2007年 | 393篇 |
2006年 | 358篇 |
2005年 | 386篇 |
2004年 | 382篇 |
2003年 | 329篇 |
2002年 | 355篇 |
2001年 | 221篇 |
2000年 | 256篇 |
1999年 | 225篇 |
1998年 | 117篇 |
1997年 | 98篇 |
1996年 | 76篇 |
1995年 | 69篇 |
1994年 | 68篇 |
1993年 | 63篇 |
1992年 | 184篇 |
1991年 | 151篇 |
1990年 | 160篇 |
1989年 | 189篇 |
1988年 | 156篇 |
1987年 | 150篇 |
1986年 | 132篇 |
1985年 | 103篇 |
1984年 | 76篇 |
1983年 | 69篇 |
1982年 | 32篇 |
1980年 | 36篇 |
1979年 | 62篇 |
1978年 | 43篇 |
1977年 | 41篇 |
1973年 | 28篇 |
1972年 | 41篇 |
1971年 | 33篇 |
1969年 | 29篇 |
排序方式: 共有9116条查询结果,搜索用时 15 毫秒
1.
Shingo Hashimoto Masaki Katsurada Rie Muramatsu Kumiko Asai Kenichiro Tanaka Kensuke Hayashi Yoshiaki Kibe Koichiro Nakajima Yukiko Hattori Hiromitsu Iwata Jun-etsu Mizoe Hiroyuki Ogino Yuta Shibamoto 《Practical radiation oncology》2019,9(2):e149-e155
Purpose
Suppression of respiratory movement of the liver would be desirable for high-precision radiation therapy for liver tumors. We aimed to investigate the effect of our original device-free compressed shell fixation method and breathing instruction on suppression of respiratory movement. The characteristics of liver motion based on the movement of a fiducial marker were also analyzed.Methods and Materials
First, respiratory amplitudes of the liver with the device-free compressed shell were analyzed from the data of 146 patients. The effect of this shell fixing method on liver movement was evaluated. Second, as another cohort study with 166 patients, interfractional internal motion of the liver for patients fixed in the shell was calculated using the fiducial marker coordinate data of images for position setting before daily irradiation. Third, in another 12 patients, intrafractional internal motion was calculated from the fiducial marker coordinate data using x-ray images before and after irradiation.Results
The median respiratory movement without the shell, after fixing with the shell, and after instructing on the breathing method with the shell was 14.2 (interquartile range, 10.7-19.8), 11.5 (8.6-17.5), and 10.4 mm (7.3-15.8), respectively. Systematic and random errors of interfractional internal motion were all ≤2 mm in the left-right and anteroposterior directions and 3.7 and 3.0 mm, respectively, in the craniocaudal direction. Systematic and random errors of intrafractional internal motion were all ≤1.3 mm in the left-right and anteroposterior directions and 0.8 and 2.4 mm, respectively, in the craniocaudal direction.Conclusions
The device-free compressed shell fixation method was effective in suppressing the respiratory movement of the liver. Irradiation position matching using the fiducial marker can correct the interfractional internal motion on each day, which would contribute to the reduction of the margin to be given around the target. 相似文献2.
Kensuke Kudou Hiroshi Saeki Yuichiro Nakashima Shun Sasaki Tomoko Jogo Kosuke Hirose Qingjiang Hu Yasuo Tsuda Koichi Kimura Ryota Nakanishi Nobuhide Kubo Koji Ando Eiji Oki Tetsuo Ikeda Yoshihiko Maehara 《American journal of surgery》2019,217(4):757-763
Background
There were few studies assessed the postoperative sarcopenia in patients with cancers. The objective of present study was to assess whether postoperative development of sarcopenia could predict a poor prognosis in patients with adenocarcinoma of esophagogastric junction, (AEG) and upper gastric cancer (UGC).Methods
Patients with AEG and UGC who were judged as non-sarcopenic before surgery were reassessed the presence of postoperative development of sarcopenia 6 months after surgery. Patients were divided into the development group or non-development group, and clinicopathological factors and prognosis between these two groups were analyzed.Results
The 5-year overall survival rates were significantly poorer in the development group than non-development group (68.0% vs. 92.6%, P?=?0.0118). Multivariate analyses showed that postoperative development of sarcopenia was an independent prognostic factor for poor overall survival (P?=?0.0237).Conclusions
Postoperative development of sarcopenia was associated with a poor prognosis in patients with AEG and UGC. 相似文献3.
4.
Akihiko Bo Shinichi Imura Hironori Omori Yasuhiro Okumura Masao Ando Hisatoshi Baba Patrick White Al Zarnowski 《Journal of orthopaedic science》1997,2(5):301-312
The fit and fill of the femoral canal are critical to the success of cementless femoral stems in total hip arthroplasty. It
is difficult for conventional stems to provide a good fit and fill for the femora of patients with secondary osteoarthritis.
Based on measurements of 100 femora of these patients, we designed two types of Fukui Medical School (FMS) stems with a proximal
lateral flare that differed in the medial radius. We compared the fit and fill of the FMS stems with those of four conventional
stems, using computer simulation. The mean proximal fit and total fit of the FMS stems were 46% and 53% respectively, a significant
improvement compared with the other stems examined. The mean fill of FMS stems was 82% at the lower end of the lesser trochanter
and 84% at the upper end of the isthmus, values that were significantly higher than those of the other stems. Since September
1995, we have implanted FMS stems in 15 hips with secondary osteoarthritis. Radiographic evaluations showed that the canal
fill of the FMS stems was significantly greater in the proximal femur compared with other stems previously inserted at our
department.
A summary of this paper was presented at the 9th Symposium on Computer-Assisted Radiology; June 1995, Berlin, and at the 8th
International Symposium on Technology in Arthroplasty; September 1995, Puerto Rico. 相似文献
5.
Multicentricity of hepatocellular carcinoma (HCC) is considered, especially in patients with liver cirrhosis. This paper describes an operative case of a male patient with probable multicentric development of HCC in precirrhotic fibrosis. The main tumors inside the capsule were completely necrotic due to transarterial embolization (TAE). Histologic examination disclosed discrete tiny nodules of HCC that were not detected grossly. They showed highly differentiated trabecular arrangements: Edmondson I. A scirrhous type was noted in the center of the tumors. At the borders of the tumors the carcinoma cells exhibited replacing growth patterns and it was thought that they developed multicentrically. Partial resection must be performed as extensively as possible in a case such as the present one. 相似文献
6.
7.
Definition of carcinoma of the gastric cardia 总被引:8,自引:0,他引:8
A. Misumi M.D. A. Murakami K. Harada K. Baba M. Akagi 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1989,374(4):221-226
Summary This study concerns the definition of carcinoma of the gastric cardia. The topography of the esophagogastric mucosal junction (mucosal EGJ) was investigated with an endoscope in 182 patients who were free of hiatal hernias, ulcers, and neoplasms in the esophagus and stomach. The relationship between the EGJ and the cardiac gland area was then examined histologically in 56 resected specimens containing intact EGJs and cardia gland areas. Furthermore the cancerous center was determined; the shortest distance between the cancerous center and the EGJ and the amount of esophageal invasion were measured in 102 resected carcinomas located close to the junction; the carcinomas contained the EGJ and were good enough for pathohistological examination. The EGJ was located 0.5–1.0 cm proximal to the His angle (the gastric cardia) in radiological and endoscopic examinations. Histologically the cardiac gland area was found to straddle the EGJ at a range of about 1 cm proximal and 2 cm distal to the junction. Among the upper stomach carcinomas, most of the tumors (87.5%) whose center was located within 2 cm from the EGJ invaded the esophagus. In conclusion, carcinoma of the gastric cardia is defined as a lesion with its center located within 1 cm proximal and 2 cm distal to the EGJ.
Definition des Kardiacarcinoms
Zusammenfassung Diese Untersuchung befaßt sich mit der Definition von Carcinomen der Kardia. An 182 Patienten, die weder Hiatushernien, Ulcera noch Neoplasien des Oesophagus bzw. des Magens aufwiesen, wurde die Lage des Übergangs von der Oesophagus- zur Magenmucosa (esophagogastric mucosal junction, EGJ) endoskopisch untersucht. Dann wurde die Beziehung zwischen EGJ und dem Drüsengebiet der Kardia histologisch anhand von 56 Resektaten mit intaktem EGJ und Kardiadrüsenzone untersucht. Außerdem wurde an 102 resezierten Carcinomen mit Sitz in der Nähe des gastrooesophagealen Übergangs die kürzeste Ent fernung zwischen Carcinomzentrum und EGJ und das Ausmaß der Oesophagusinfiltration bestimmt; die Proben schlossen den EGJ ein und konnten pathohistologisch beurteilt werden. Bei der radiologischen und endoskopischen Untersuchung fand sind der EGJ 0,5–1,0 cm vom His-Winkel entfernt. Die histologische Untersuchung zeigte, daß die Kardiadrüsenzone sich vom EGJ etwa 1 cm nach proximal und 2 cm nach distal erstreckt. Die meisten Tumoren des oberen Magens (87,5%), deren Zentrum innerhalb von 2 cm vom EGJ entfernt lag, infiltrierten in den Oesophagus. Ein Kardiacarcinom ist demzufolge als Läsion zu definieren, deren Zentrum innerhalb von 1 cm proximal und 2 cm distal des EGJ liegt.相似文献
8.
The role of intracellular Zn2+ in the translocation of protein kinase C from cytosol to membrane fractions was examined by the [3H]phorbol 12,13-dibutyrate (PDBu) binding method in guinea pig cerebral synaptoneurosomes. N-methyl-d-aspartate (NMDA, 100 μM) and calcium ionophore A23187 (0.3–30 μM) decreased the binding activity in the cytosol with a concomitant increase in the membrane fractions. Pretreatment of synaptoneurosomes with a heavy metal chelator, N,N,N′,N′-tetrakis-(2-pyridylmethyl)ethylenediamine (TPEN), inhibited the NMDA- and A23187-induced changes of the distribution of [3H]PDBu binding sites in cytosol and membrane fractions. The inhibitory effect of TPEN was negated by a preincubation of TPEN with equimolar Zn2+ but not by that with Ca2+. The addition of 500 μM Zn2+ to the lysate of synaptoneurosomes induced an increase of [3H]PDBu binding activity in the membrane fraction with a concomitant decrease in the cytosol fraction, as did 100 μM Ca2+. Low concentrations of Zn2+ (10 μM), which alone had no effect on the distribution of the binding, significantly enhanced the effect of 10 μM Ca2+ in the lysate. Under those conditions TPEN inhibited the Zn2+-potentiated Ca2+-dependent changes in the binding. These results suggest that intracellular Zn2+ is essential for the agonist-induced translocation of protein kinase C in guinea pig synaptoneurosomes. 相似文献
9.
The identification of atypical testicular germ cells is often difficult by by routine histologic examination. By immunohistochemical detection of placental alkaline phosphatase (PLAP) and by periodic acid Schiff staining of glycogen, atypical germ cells were easily identified in testicular samples. Forty-one fetal and adult testes were used for a preliminary study, and 121 testes from infants and adults with either cryptorchidism or germ cell tumors were studied for the presence of atypical germ cells. Two types of clear germ cells were differentiated histochemically, and one with PLAP-positive cell surfaces and glycogen-rich cytoplasm was considered to be atypical. The alkaline phosphatase of atypical germ cells appeared to be similar to that found in a few germ cells of early fetal testes. The atypical germ cells seemed to be multi-potential malignant cells capable of developing not only into seminoma but also into other germ cell tumors. Only in yolk sac tumor of infants were the atypical germ cells absent from tumor-adjacent seminiferous tubules. 相似文献
10.
M Tatsuta H Iishi M Baba A Nakaizumi H Uehara H Taniguchi 《International journal of cancer. Journal international du cancer》1991,47(1):54-59
The effects of sulpiride on cysteamine inhibition of gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and on the BUdR labelling index of gastric mucosa were investigated in inbred Wistar rats. After 25 weeks of oral treatment with MNNG, rats received one of the following alternate-day injections: cysteamine (2 doses), cysteamine (2 doses) plus sulpiride or sulpiride. At week 52, prolonged administration of cysteamine significantly reduced the incidence of adenocarcinomas of the glandular stomach. Cysteamine at low dose had no effect on the incidence of gastric cancers, but a combination of low-dose cysteamine and sulpiride caused a significantly greater reduction in the incidence of gastric cancers. Administration of sulpiride alone had no influence on gastric carcinogenesis. The labelling index of the antral mucosa was significantly lower in rats treated with high but not low doses of cysteamine. However, a combination of low-dose cysteamine and sulpiride significantly decreased the labelling index of the antral mucosa. Our findings indicate that cysteamine suppressed gastric carcinogenesis and that sulpiride enhanced this inhibition. Because sulpiride is a dopamine antagonist, these findings also indicate that dopamine may play an important role in cysteamine inhibition of gastric carcinogenesis. 相似文献