全文获取类型
收费全文 | 16339篇 |
免费 | 879篇 |
国内免费 | 178篇 |
专业分类
耳鼻咽喉 | 134篇 |
儿科学 | 309篇 |
妇产科学 | 151篇 |
基础医学 | 1866篇 |
口腔科学 | 256篇 |
临床医学 | 946篇 |
内科学 | 5256篇 |
皮肤病学 | 372篇 |
神经病学 | 995篇 |
特种医学 | 609篇 |
外科学 | 2769篇 |
综合类 | 64篇 |
一般理论 | 3篇 |
预防医学 | 319篇 |
眼科学 | 433篇 |
药学 | 921篇 |
中国医学 | 37篇 |
肿瘤学 | 1956篇 |
出版年
2024年 | 15篇 |
2023年 | 141篇 |
2022年 | 246篇 |
2021年 | 535篇 |
2020年 | 306篇 |
2019年 | 407篇 |
2018年 | 425篇 |
2017年 | 348篇 |
2016年 | 421篇 |
2015年 | 448篇 |
2014年 | 605篇 |
2013年 | 706篇 |
2012年 | 1205篇 |
2011年 | 1327篇 |
2010年 | 776篇 |
2009年 | 581篇 |
2008年 | 1012篇 |
2007年 | 1159篇 |
2006年 | 1077篇 |
2005年 | 1068篇 |
2004年 | 973篇 |
2003年 | 902篇 |
2002年 | 931篇 |
2001年 | 164篇 |
2000年 | 122篇 |
1999年 | 146篇 |
1998年 | 183篇 |
1997年 | 176篇 |
1996年 | 150篇 |
1995年 | 120篇 |
1994年 | 99篇 |
1993年 | 98篇 |
1992年 | 66篇 |
1991年 | 68篇 |
1990年 | 63篇 |
1989年 | 63篇 |
1988年 | 28篇 |
1987年 | 30篇 |
1986年 | 17篇 |
1985年 | 20篇 |
1984年 | 23篇 |
1983年 | 14篇 |
1982年 | 18篇 |
1981年 | 19篇 |
1980年 | 16篇 |
1979年 | 10篇 |
1977年 | 10篇 |
1976年 | 8篇 |
1975年 | 8篇 |
1971年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
A simple and rapid analysis system for single nucleotide polymorphisms (SNPs) was investigated for the FUT2 gene using the temperature gradient gel electrophoresis (TGGE) method. The 426-bp or 259-bp FUT2 fragments were amplified from heterozygous samples using primers, and the heteroduplex and homoduplex bands were detected by TGGE. The FUT2 fragments amplified from homozygous samples were denatured and re-annealed with a known sequence fragment, forming heteroduplex bands which were analyzed by TGGE. The fragment patterns of homoduplex and heteroduplex bands in TGGE were specific to the genotypes, and more specifically, the number of heteroduplex bands and the migration of the homoduplex bands corresponded to the number of nucleotide substitutions and the change in GC content due to the substitutions, respectively. Thus, the TGGE technique can act as a high-throughput method for the detection and the presumption of sequences of known and unknown SNPs in the FUT2 gene. 相似文献
993.
994.
995.
Patient-controlled Dietary Schedule Improves Clinical Outcome after Gastrectomy for Gastric Cancer 总被引:1,自引:0,他引:1
Although studies have shown that early oral feeding after abdominal surgery is feasible, the optimal dietary schedule has
not been established. This study was conducted prospectively to compare the clinical outcome of patient-controlled dietary
schedule with that of conventional dietary schedule after gastric resection for early cancer. Patients in the patient-controlled
diet (PC) group (n = 53) received a solid diet on demand; patients in the conventional regimen (CR) group (n = 50) received a solid diet from postoperative day (POD) 10. All patients underwent distal gastrectomy for early gastric
cancer. A liquid diet was tolerated by the PC group on POD 2, and a solid diet was taken on POD 6 after gastrectomy, earlier
than in the CR group. The postoperative hospital stay was 18.5 ± 5.9 days (10–40) in the PC group, versus 21.7 ± 8.8 days
(14–57) in the CR group (p = 0.02). Patients in the PC group had a higher daily oral intake of calories on POD 10 than those in the CR group (p = 0.02). Changes in body weight and serum albumin during the postoperative period and after discharge, and the incidence
of complications and variances from clinical pathways did not show significant differences between the two groups. The PC
schedule was feasible after distal gastrectomy for early gastric cancer. It improved the clinical outcome, with a shorter
postoperative hospital stay and a higher oral energy intake on early phase, compared with the CR schedule. Moreover, the PC
approach was useful for establishing the optimal dietary schedule and improving the clinical pathway. 相似文献
996.
Yoshiaki?Mihara Keiichi?KubotaEmail author Takehiko?Nemoto Kyu?Rokkaku Satoshi?Yamamoto Masatsugu?Tachibana Atsushi?Sakuma Yasuo?Ohkura Takahiro?Fujimori 《Journal of gastrointestinal surgery》2005,9(4):498-502
A 59-year-old woman underwent surgery for uterine corpus cancer in March 1998. She also underwent pylorus-preserving pancreaticoduodenectomy
with pancreaticogastrostomy for common bile duct cancer in November 1998. She was followed up at our outpatient clinic after
pylorus-preserving pancreaticoduodenectomy. In November 2002, her carcinoembryonic antigen level became elevated and abdominal
ultrasound revealed a huge tumor. Gastroscopy showed a Borrmann type 3 tumor at the anastomosis of the pancreaticogastrostomy,
and a biopsy revealed adenocarcinoma. With a diagnosis of advanced gastric cancer, she underwent total gastrectomy, splenectomy,
and residual pancreatectomy in January 2003. The pathologic .ndings revealed that the gastric cancer was separated from the
pancreas, suggesting that the cancer had developed from the stomach. The present report describes a rare case of gastric cancer
that had developed at the anastomosis of a pancreaticogastrostomy. 相似文献
997.
Maruyama N Fukuma A Ihara I Ando S Yamasaki T Moritake K 《Neurologia medico-chirurgica》2005,45(5):246-248
A rare abnormality of the A1 segment of the anterior cerebral artery (ACA) is reported. The right ACA bifurcated into two parts at the middle point of the A1 segment, and these segments did not rejoin. The superior right A1 segment connected with the left A1 and formed a single pericallosal artery. The inferior right A1, from which the right ophthalmic artery originated, had no connection with the left A1. 相似文献
998.
A 74-year-old man with chronic renal failure under hemodialysis via the left upper extremity underwent an off-pump coronary artery bypass (OPCAB). The left internal thoracic artery (LITA), which was harvested in a skeletonized manner, was anastomosed to the left anterior descending artery (LAD). Postoperatively, he complained of chest pain only during dialysis. Angiography revealed a kinking in the LITA. However, myocardial scintigraphy revealed no ischemia. One year after OPCAB, left ventriculography revealed akinesis and myocardial scintigraphy revealed no viability in the anterior wall. This suggested that the viability was lost due to graft kinking and steal phenomenon during hemodialysis. If the length of the skeletonized ITA graft is redundant, kinking of the graft rarely occurs after the chest is closed. We also suggest that to avoid the kinking of the ITA graft, fibrin glue should be used to paste the ITA graft running in a gentle curve. 相似文献
999.
Imamaki M Nakajima N Masuda M Ishida A Shimura H Miyazaki M 《Journal of cardiac surgery》2005,20(5):408-411
OBJECTIVE: Preceding selective cerebral perfusion (P-SCP) is a method whereby SCP and systemic perfusion start simultaneously, and the arch vessels are clamped. Cerebral circulation is isolated from systemic circulation to avoid cerebral embolization due to detachment of atherosclerotic material from the aorta, caused by the "sandblasting" effect of high-velocity jets of blood exiting the aortic cannula. However, neither the safety of SCP at normothermia nor the influence of extended SCP time has been sufficiently clarified. To clarify the safety of P-SCP, the comparison study of P-SCP and conventional SCP (C-SCP) was performed retrospectively. METHODS: Fifty-seven patients (C-SCP group: 29 patients; P-SCP: 28 patients) underwent surgery between 1992 and 2002. RESULTS: Nine (15.8%) in-hospital death occurred; 4 in the C-SCP group (13.8%) and 5 in the P-SCP group (17.9%) (NS). The SCP time was 136.6 +/- 68.5 minutes in the C-SCP group and 195.8 +/- 30.7 minutes in the P-SCP group (p < 0.05). One patient in each group exhibited postoperative neurological dysfunction. CONCLUSION: It may be little dangerous to initiate the SCP with normothermia. P-SCP may be useful in cases in which there is pedunculated atherosclerotic material, or mural thrombus in the ascending and arch aorta. 相似文献
1000.
Biphasic anti-osteoclastic action of intravenous alendronate therapy in multiple myeloma bone disease 总被引:1,自引:0,他引:1
Kitano M Ogata A Sekiguchi M Hamano T Sano H 《Journal of bone and mineral metabolism》2005,23(1):48-52
Multiple myeloma is a malignancy of plasma cells with osteolytic bone destruction. Bisphosphonates inhibit osteoclast activity and are widely used for the treatment of myeloma bone disease. We analyzed the changes in urinary cross-linked N-telopeptides of collagen (u-NTx) and urinary calcium (u-Ca) after bisphosphonate alendronate therapy in ten patients with myeloma bone disease. In all patients, the levels of u-Ca and u-NTx decreased within a week. After the maximum decrease of u-NTx, u-NTx started increasing in half of the patients. However, this further increase in u-NTx decreased again without any additional therapy. Disease severity and pretreatment u-NTx concentrations did not differ between patients with and without the rebound. Patients who did not have rebound had decreased bone marrow monocytes and decreased serum concentrations of interleukin 18, which is produced by monocytes. Our results suggest that impaired activity of monocytes, which are possible osteoclast precursors, is related to reduced bone destruction in multiple myeloma. 相似文献