全文获取类型
收费全文 | 12425篇 |
免费 | 681篇 |
国内免费 | 111篇 |
专业分类
耳鼻咽喉 | 121篇 |
儿科学 | 230篇 |
妇产科学 | 137篇 |
基础医学 | 1455篇 |
口腔科学 | 211篇 |
临床医学 | 849篇 |
内科学 | 3619篇 |
皮肤病学 | 223篇 |
神经病学 | 778篇 |
特种医学 | 358篇 |
外科学 | 2260篇 |
综合类 | 72篇 |
预防医学 | 325篇 |
眼科学 | 215篇 |
药学 | 801篇 |
中国医学 | 34篇 |
肿瘤学 | 1529篇 |
出版年
2023年 | 112篇 |
2022年 | 221篇 |
2021年 | 385篇 |
2020年 | 223篇 |
2019年 | 301篇 |
2018年 | 395篇 |
2017年 | 237篇 |
2016年 | 369篇 |
2015年 | 376篇 |
2014年 | 450篇 |
2013年 | 505篇 |
2012年 | 908篇 |
2011年 | 952篇 |
2010年 | 512篇 |
2009年 | 420篇 |
2008年 | 741篇 |
2007年 | 833篇 |
2006年 | 752篇 |
2005年 | 757篇 |
2004年 | 693篇 |
2003年 | 590篇 |
2002年 | 641篇 |
2001年 | 160篇 |
2000年 | 146篇 |
1999年 | 146篇 |
1998年 | 133篇 |
1997年 | 117篇 |
1996年 | 101篇 |
1995年 | 85篇 |
1994年 | 88篇 |
1993年 | 67篇 |
1992年 | 80篇 |
1991年 | 85篇 |
1990年 | 48篇 |
1989年 | 50篇 |
1988年 | 61篇 |
1987年 | 51篇 |
1986年 | 51篇 |
1985年 | 58篇 |
1984年 | 38篇 |
1983年 | 42篇 |
1982年 | 16篇 |
1981年 | 33篇 |
1980年 | 20篇 |
1979年 | 22篇 |
1978年 | 13篇 |
1977年 | 20篇 |
1976年 | 13篇 |
1974年 | 13篇 |
1971年 | 13篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Calcification and osteopontin localization in the peritoneum of patients on long-term continuous ambulatory peritoneal dialysis therapy. 总被引:3,自引:0,他引:3
Yuichi Nakazato Yasuyoshi Yamaji Naoki Oshima Matsuhiko Hayashi Takao Saruta 《Nephrology, dialysis, transplantation》2002,17(7):1293-1303
BACKGROUND: Peritoneal calcification is an uncommon complication of continuous ambulatory peritoneal dialysis (CAPD), which is mainly observed in patients on long-term therapy. Although some asymptomatic patients must have microscopic calcification in their peritoneum, little information on this topic has been published. Recent studies have revealed active participation of adhesive/chemotactic protein osteopontin (OPN) in dystrophic calcification. METHODS: Peritoneal tissue was obtained by biopsy or at autopsy from 18 CAPD patients (median duration, 122 months), 5 control haemodialysis (HD) patients, and 3 pre-CAPD patients. The distribution of calcium deposits and OPN protein was determined by von Kossa staining and immunohistochemistry, respectively. Smooth muscle cells and macrophages were identified with anti-alpha smooth muscle actin (alpha-SMA) and anti-CD68 antibodies. RESULTS: Calcium deposits with various configurations were observed in specimens from 12 of the 18 CAPD patients. They included massive calcification facing the peritoneal cavity, scattered granular or crystalloid deposits in the submesothelial stroma, and oval-shaped deposits formed within hyalinized vasa. Most were present in highly sclerosed areas and accompanied by extracellular OPN precipitation. Cytoplasmic OPN was detected in infiltrating leukocytes, granulation tissue cells, fibroblast-like cells and mast cells. Computerized tomography examination also detected peritoneal calcification in seven of the CAPD patients. No calcium deposits or OPN staining was detected in control specimens. CONCLUSIONS:The results of our study suggest that microscopic peritoneal calcification is frequent in patients on CAPD for more than 10 years. Myofibroblast infiltration, OPN expression, calcium deposition, and associated OPN precipitation seem to be components of the peritoneal changes in such patients. 相似文献
92.
Shimokawa T Minato N Yamada N Takeda Y Hisamatsu Y Itoh M 《The Annals of thoracic surgery》2002,74(6):408-2100
BACKGROUND: Use of an aortic partial clamp for proximal anastomosis during off-pump coronary artery bypass is known to increase the risk of fatal complications. The purpose of this study was to assess the management of the ascending aorta evaluated with epiaortic ultrasonography during off-pump coronary artery bypass. METHODS: Intraoperative ultrasonography of the ascending aorta with a 10-MHz probe was performed consecutively in 155 patients undergoing off-pump coronary artery bypass between August 1999 and July 2001. The findings from ultrasonography, surgical modifications, and operative results were analyzed. RESULTS: In 54 patients (34.8%), epiaortic ultrasonography showed atherosclerotic findings in the anterior side of the ascending aorta (group A). The remaining 101 patients had either normal findings or atherosclerotic findings in only the posterior side (group NA). A proximal anastomosis to the aorta was preoperatively planned in 117 patients (group A, 42; group NA, 75). In group A, a graft modification without clamping was implemented in 29 patients (24.8% of 117 patients), whereas the clamp site was modified to a different segment in 13 patients (11.1% of 117 patients). In all 75 patients in group NA, partial clamping was used in the standard fashion. There were no cerebral infarctions or operative deaths related to partial clamping. However, aortic dissection occurred in 1 patient in group NA. CONCLUSIONS: In 35% of patients undergoing off-pump coronary artery bypass, epiaortic ultrasonography identified atherosclerotic findings in the anterior wall of the ascending aorta. This study suggests that revascularization without aortic manipulation during off-pump coronary artery bypass is indicated in as many as 25% of patients. 相似文献
93.
Taichi Tsuji Yukihiro Matsuyama Manabu Goto Yu Yimin Koji Sato Yukiharu Hasegawa Naoki Ishiguro 《Journal of orthopaedic science》2002,7(5):519-523
Low back pain is an enormous clinical and public health problem. When we use spinal instrumentation, measurements of spinal
and leg alignment in the standing position are thought to be important. Knee joint pain has also become an enormous clinical
problem in the increasing elderly population. However, the correlation between spinal alignment, particularly sacral inclination,
and knee joint pain is not clear. We examined the correlation between lumbar lordosis, sacral inclination, and patellofemoral
joint pain in elderly subjects. Three hundred and ninety-nine people aged 50–85 years were examined. Clinical findings and
physical status were determined. Measurements and determination of total lordosis from L1 to S1 and sacral inclination were
made from standing radiographs. The knee joints were evaluated by using the standing knee flexion angle, radiographs, and
the patellofemoral (PF) joint grinding test. Thirty-nine percent of subjects were excluded because they had definite osteo-arthritis
at the femorotibial joints. Fifty-eight percent of the subjects had felt low back pain within the previous 3 months, and 16%
of the subjects complained of PF joint grinding pain. Sixteen percent of the subjects showed knee flexion when standing. There
was a significant difference in sacral inclination between the groups with and without PF joint grinding pain (P < 0.01). Sacral inclination was approximately 5° less in the knee flexion group. A correlation between sacral inclination
and PF joint pain is defined, and its prevalence in the elderly is reported. We speculate that this phenomenon is caused by
changing of lumbar alignment. In addition, we think this is a new pathological concept that we call the knee – spine syndrome.
Received: July 23, 2001 / Accepted: May 2, 2002 相似文献
94.
Eisuke Arai Yoshihiro Nishida Satoshi Tsukushi Hideshi Sugiura Naoki Ishiguro 《Clinical orthopaedics and related research》2010,468(5):1384-1389
Granular cell tumors are uncommon but typically histologically benign neoplasms that occasionally behave as malignant tumors.
Differentiation of benign granular cell tumors from malignant counterparts with radiographic and/or histologic analysis is
crucial for physicians. We retrospectively studied five cases of intramuscular granular cell tumors arising in the lower extremities.
All tumors had been histologically diagnosed as benign and were resected with a wide surgical margin. The minimum followup
was 1 year (mean, 45 months; range, 12–119 months) after surgery. Four patients had no local recurrence or distant metastasis
(at a minimum of 18 months followup), whereas one patient with lymph node metastasis had a recurrence and distant metastasis
3 months after surgery resulting in death. Intramuscular granular cell tumors can be diagnosed based on their characteristic
MRI features, such as peripheral high intensity on T2-weighed images, and histologic evaluation. The histologic criteria described
by Fanburg-Smith et al. can differentiate malignant granular cell tumors from benign tumors. A wide resection seems suitable
for most granular cell tumors in the extremities. 相似文献
95.
Osteoprotegerin (OPG) inhibits interaction of the receptor-activator of nuclear factor-kappaB (RANK) ligand (RANKL) with its receptor RANK, which is expressed on osteoclasts. OPG appeared to accelerate vascular calcification in vitro by the inhibition of vascular osteoclast-like cells. On the contrary, early-onset arterial calcification was observed in OPG-deficient mice. We measured the coronary artery calcification score (CACS) and abdominal aortic calcification score (AAoCS) by multi-detector computed tomography in 30 pre-dialysis CKD patients (eGFR 20 mL/min on average). Biomarkers were measured, including serum OPG, soluble RANKL (sRANKL) and tartrate-resistant acid phosphatase (TRACP) -5b (the biomarker of osteoclasts independent of renal function). The median values of CACS and AAoCS were 54.4 and 1,088 Agatston units (AU), respectively. Serum OPG was increased and serum sRANKL was decreased. In a multivariate logistic regression analysis using CACS > or = 100 AU as the outcome variable, CACS was found to be positively correlated with serum corrected Ca x iP product and serum OPG, though it was not correlated with serum TRACP-5b. ROC curve analysis showed that the serum OPG cutoff value predicting CACS > or = 100 AU was 5.2 pmol/L (624 pg/mL). In a stepwise regression analysis, log (AAoCS + 1) was positively correlated with serum OPG alone, but it was not correlated with age, eGFR, serum albumin and bone alkaline phosphatase (BAP). No correlation was found between serum OPG and serum TRACP-5b. In conclusion, vascular calcification in pre-dialysis CKD patients was correlated with an increase in OPG, but was independent of serum TRACP-5b. The decrease in serum sRANKL may have been caused by the increase in OPG production. 相似文献
96.
Naoki Ishii Noriyuki Horiki Toshiyuki Itoh Masataka Maruyama Michitaka Matsuda Takeshi Setoyama Shoko Suzuki Shino Uchida Masayo Uemura Yusuke Iizuka Katsuyuki Fukuda Koyu Suzuki Yoshiyuki Fujita 《Surgical endoscopy》2010,24(6):1413-1419
Background
Rectal carcinoid tumors 10 mm in diameter or smaller located within the submucosal layer can be cured by local excision including endoscopic treatment. But complete resection of these tumors with endoscopic polypectomy is difficult. This study aimed to evaluate the usefulness of endoscopic submucosal dissection (ESD) and endoscopic ultrasonography (EUS) for the treatment of rectal carcinoid tumors.Methods
In this study, 22 rectal carcinoid tumors in 21 patients were evaluated with EUS and treated using ESD from January 2004 to December 2008.Results
The mean size of the resected tumors was 6.1 mm (range, 2.0–10 mm) on histopathologic evaluations. When the sizes of the tumors shown by EUS and histopathologic evaluation were compared, the mean values were not significantly different. All the tumors were located within the submucosal layer, and the accuracy of the preoperative depth determination with EUS was 100% (22/22). The mean duration of the ESD procedure was 37 min (range, 20–71 min). The overall rate of en bloc resection with ESD was 100% (22/22). Although postoperative bleeding occurred in two cases (9%), both cases were successfully managed by endoscopic hemostasis. No perforation or recurrence was observed during the mean follow-up period of 30 months (range, 7–66 months).Conclusions
Endoscopic submucosal dissection and preoperative assessment with EUS are effective for treating rectal carcinoid tumors and enabling en bloc resection. 相似文献97.
Naoki Ishii Toshiyuki Itoh Noriyuki Horiki Michitaka Matsuda Takeshi Setoyama Shoko Suzuki Masayo Uemura Yusuke Iizuka Katsuyuki Fukuda Koyu Suzuki Yoshiyuki Fujita 《Surgical endoscopy》2010,24(8):1941-1947
Background
Large superficial neoplasias of the ileocecal region pose an increased degree of complexity for endoscopic resection. This study aimed to evaluate the safety and efficacy of endoscopic submucosal dissection (ESD) for large superficial colorectal neoplasias including ileocecal lesions.Methods
A total of 33 superficial colorectal neoplasias, including eight neoplasias in the ileocecal region, were treated with ESD from December 2005 to April 2009. Therapeutic efficacy, complications, and follow-up results were retrospectively evaluated among three groups: ileocecal region, colon, and rectum.Results
The mean size of all resected neoplasias was 35 ± 15 mm (range, 20–80 mm) and that of all resected specimens was 41 ± 15 mm (range, 23–82 mm). The mean procedural time was 121 ± 90 min (range, 22–420 min). The difference in mean values among the three groups was not significant. The overall rate of en bloc resection was 91% (30/33). Histopathologically, both the lateral and vertical margins in the specimens resected en bloc tested negative (30/30). The rate for en bloc resection in the ileocecal region did not differ significantly from that for the other two groups (p = 0.20 compared with the rate for the colon and p = 0.12 compared with the rate for the rectum). Complications such as perforation and postoperative bleeding did not occur in the ileocecal group. No recurrence was observed in any cases during the mean follow-up period of 20 ± 12 months (range, 4–44 months).Conclusions
The ESD approach is safe and effective for treating large superficial neoplasias of the ileocecal region such as other colorectal neoplasias. 相似文献98.
Naoki Ishii Shino Uchida Toshiyuki Itoh Noriyuki Horiki Michitaka Matsuda Takeshi Setoyama Shoko Suzuki Masayo Uemura Yusuke Iizuka Katsuyuki Fukuda Koyu Suzuki Yoshiyuki Fujita 《Surgical endoscopy》2010,24(9):2110-2119
Background
Safety and efficacy of endoscopic submucosal dissection (ESD) for esophageal neoplasias have not been adequately investigated in elderly patients. This study was designed to evaluate the safety and efficacy of ESD for esophageal neoplasias in elderly patients.Methods
Fifty-three superficial esophageal neoplasias treated with ESD using a combination of small-caliber-tip transparent hood and flex knife from May 2006 to June 2009 were divided into elderly group (aged 70 years or older: 25 lesions in 23 patients) and nonelderly group (younger than aged 70 years: 28 lesions in 25 patients). Therapeutic efficacy, complications, and follow-up results were evaluated retrospectively.Results
The history of cerebral infarction or cardiopulmonary disease and the usage of antiplatelet agents or anticoagulants were significantly higher in elderly group (p 0.0050 and p 0.0013, respectively). Median procedural times in the elderly group and the nonelderly group were 93 ± 53 (range, 42–235) min and 95 ± 55 (range, 40–230) min (p 0.73), respectively. Median sizes of the neoplasias and the resected specimens were 14 ± 11 (range, 5–45) mm and 15 ± 17 (range, 5–83) mm (p 0.56), and 35 ± 12 (range, 18–60) mm and 38 ± 17 (range, 18–90) mm (p 0.38), respectively. En bloc resection rate was 100% in each group. Body temperature and white blood cell counts of the next day after ESD were significantly higher in the nonelderly group than in the elderly group (p 0.0087 and p 0.0043, respectively). There were no complications, such as postoperative bleeding or perforation, in each group. The median follow-up period of 23 ± 10 (range, 4–35) months in the elderly group revealed no local or distant metastasis.Conclusions
ESD with a combination of small-caliber-tip transparent hood and flex knife is a safe and effective treatment for superficial esophageal neoplasia in elderly and nonelderly patients. 相似文献99.
Suzuki Y Sugiyama N Okamoto A Yamamoto H Hatakeyama S Yoneyama T Hasimoto Y Koie T Kamimura N Ohyama C 《Hinyokika kiyo. Acta urologica Japonica》2010,56(10):581-583
A 62-year-old man presented with a giant tumor in the pelvic cavity that was incidentally revealed by abdominal ultrasonography. Abdominal magnetic resonance imaging showed the heterogenous tumor in the pelvis with cystic components. The tumor was 10.8 × 10.5 × 11.7 cm in diameter and adhered to the sacral wall. The tumor was extirpated following diagnosis as a benign neurogenic tumor by needle biopsy. The pelvic cavity was occupied by the tumor rigidly adhered to the sacrum. The histopathological diagnosis of the specimen was benign schwannoma, type Antoni A. 相似文献
100.
Uchino H Asano T Nakayama N Kuroda S Houkin K 《No shinkei geka. Neurological surgery》2011,39(1):59-63
The authors present the case of a 61-year-old male with a de novo fusiform vertebral artery aneurysm, probably due to non-traumatic dissection. He underwent flow diversion therapy, using a double overlapping technique, because the origin of the contralateral vertebral artery was stenotic. Placement of two stents resulted in marked reduction of blood flow in the aneurysm. Postoperative course was uneventful. Follow-up 3D-CT angiography revealed a patent blood flow in the stent and a gradual progression of intra-aneurysmal thrombosis. Flow diversion therapy can potentially obliterate the complicated cerebral aneurysm with the preservation of blood flow in the parent artery, and would be one of the important therapeutic options in patients with complicated aneurysms in which conventional strategies such as neck clipping, endovascular coiling and parent artery occlusion are not feasible or contraindicated. 相似文献