首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   5758篇
  免费   248篇
  国内免费   23篇
耳鼻咽喉   17篇
儿科学   107篇
妇产科学   108篇
基础医学   697篇
口腔科学   90篇
临床医学   339篇
内科学   1471篇
皮肤病学   188篇
神经病学   454篇
特种医学   139篇
外科学   1037篇
综合类   19篇
一般理论   1篇
预防医学   91篇
眼科学   76篇
药学   277篇
中国医学   18篇
肿瘤学   900篇
  2023年   53篇
  2022年   83篇
  2021年   118篇
  2020年   84篇
  2019年   94篇
  2018年   103篇
  2017年   90篇
  2016年   114篇
  2015年   110篇
  2014年   153篇
  2013年   208篇
  2012年   301篇
  2011年   426篇
  2010年   219篇
  2009年   176篇
  2008年   372篇
  2007年   399篇
  2006年   343篇
  2005年   408篇
  2004年   388篇
  2003年   366篇
  2002年   321篇
  2001年   50篇
  2000年   62篇
  1999年   87篇
  1998年   99篇
  1997年   86篇
  1996年   89篇
  1995年   77篇
  1994年   73篇
  1993年   47篇
  1992年   47篇
  1991年   47篇
  1990年   29篇
  1989年   31篇
  1988年   36篇
  1987年   18篇
  1986年   19篇
  1985年   17篇
  1984年   20篇
  1983年   12篇
  1982年   9篇
  1981年   14篇
  1980年   26篇
  1979年   15篇
  1978年   15篇
  1977年   19篇
  1976年   8篇
  1975年   13篇
  1973年   7篇
排序方式: 共有6029条查询结果,搜索用时 15 毫秒
51.
A 30-year-old female developed moyamoya syndrome after gamma knife surgery (GKS) for cerebral arteriovenous malformation (AVM), and was treated with bypass surgery. She suffered from flittering scotoma, right transient hemianopsia, and headache for 1 year. Cerebral angiography revealed a Spetzler-Martin grade III AVM located in the left occipital lobe. After staged embolization, GKS was performed with a minimum dose of 20 Gy to the periphery of the nidus at the 50% isodose level of the maximum target dose. Gradual nidus regression was achieved, and the clinical symptoms disappeared completely. However, at 30 months after GKS, the patient suffered transient ischemic attack. Cerebral angiography showed left middle cerebral artery occlusion with moyamoya vessels. The patient underwent direct and indirect bypass surgery. After surgery, the patient was free from ischemic symptoms. Chronic inflammation and long-term changes in expression of cytokines and growth factors after GKS may have triggered this case.  相似文献   
52.
At the time of diagnosis, 20% to 25% of patients with colorectal cancer already have liver metastases, the presence of which is a most important prognostic factor. A 64-year-old man was admitted to our hospital for investigation of anemia and multiple liver tumors. Examinations revealed ascending colon carcinoma with more than 40 liver metastases and 2 lung metastases. We performed right hemicolectomy with lymph node dissection, which was followed by 5-fluorouracil/leucovorin, oxaliplatin, plus bevacizumab (FOLFOX-BV). After 4 courses of chemotherapy, the lung metastases were in complete remission and the liver metastases had shrunk. We suggested the option of radical liver resection, but the patient declined initially as he had not suffered any severe side effects of FOLFOX-BV. After 23 courses of the chemotherapy, he agreed to undergo hepatectomy. We performed extended right lobectomy with partial left and caudal lobe resection. All of the macroscopic metastatic lesions were resected. Histopathologically, viable cancer cells were recognized in 7 of the 43 liver metastatic lesions. Postoperatively, FOLFOX-BV was restarted and continued for 10 months. At the time of writing, 15 months after the hepatectomy, the patient was well without evidence of recurrence of the cancer.  相似文献   
53.
Quality of life in patients with spinal osteoporosis is impaired by the decline of spinal mobility. However, the factors related to the spinal mobility in these patients are still unclear. We evaluated the possible factors affecting spinal mobility in patients with postmenopausal osteoporosis. A total of 128 postmenopausal women with osteoporosis aged over 50 years (mean, 70 years) were included in this study. The thoracic and lumbar kyphosis angles and range of motion (ROM) of the total spine were measured in the upright position and at maximum flexion/extension with a computer-assisted device. The paravertebral muscle thicknesses (PVMT) of thoracic and lumbar spine in the upright position were measured using an ultrasound unit. The number of vertebral fractures was evaluated with radiographs of the spine. Isometric back extensor strength (BES) was evaluated with a strain-gauge dynamometer. Correlations between these variables were then analyzed. Age ( r =–0.412), lumbar kyphosis angle ( r =–0.284), BES ( r =0.369), PVMT at the lumbar spine ( r =0.227) and the number of vertebral fractures ( r =–0.260) showed significant correlations with total spinal ROM ( P <0.05). However, no significant correlations were observed between the total spinal ROM and PVMT at the thoracic spine ( r =–0.069) or thoracic kyphosis angle ( r =–0.138). Multiple regression analysis revealed that the BES was the most significant contributor to the total spinal ROM. The present study suggests a possible association between BES and spinal mobility in patients with postmenopausal osteoporosis.  相似文献   
54.
Granular cell tumor of the neurohypophysis is a rare disease entity. To our knowledge, this is the first report concerning a granular cell tumor of the neurohypophysis associated with optic tract edema. A 55-year-old man underwent brain magnetic resonance imaging (MRI) for a medical check-up, and a suprasellar tumor was detected. Brain computed tomography (CT) demonstrated a well delineated, homogenous, slightly hyperdense suprasellar tumor. MRI detected a lobular tumor that was isointense on T1-weighted images, hypointense on T2-weighted images, and showed homogeneous enhancement after administration of a gadopentetate dimeglumine. T2-weighted images and fluid-attenuated inversion recovery (FLAIR) images demonstrated a hyperintense region in the optic tract. Subtotal tumor resection was performed, and histological examination confirmed the diagnosis of granular cell tumor. Postoperative MRI showed that the tumor volume was reduced and optic tract edema diminished compared with the preoperative findings. We also review the literature focusing on radiographic findings, and compare the effectiveness of MRI and CT for diagnosing granular cell tumor of the neurohypophysis.  相似文献   
55.
We report a rare case of Stanford type A acute aortic dissection associated with a distal aortic arch atherosclerotic aneurysm. A 71-year-old female was referred to us with the diagnosis of thrombosed Stanford type A acute aortic dissection, however on the nextday transesophageal echocardiography revealed the false lumen has been recanalized. In the operation, there was a distal aortic arch atherosclerotic aneurysm which was unidetified at the preoperation. It is very rare that the dissection originated from atherosclerotic aneurysm and proceeded to proximal and distal portion of the aorta.  相似文献   
56.
Objective:   To characterize the clinical outcome in a large contemporary series of Japanese patients with newly diagnosed Ta, T1 non-muscle invasive bladder cancer who underwent transurethral bladder tumor resection with or without intravesical chemotherapy or Bacillus Calmette-Guérin (BCG) therapy.
Methods:   We developed a database incorporating newly diagnosed non-muscle invasive bladder cancer data and outcomes from a Japanese bladder cancer registry between 1999 and 2001 and identified a study population of 3237 consecutive patients who had complete data based on pathological features. Median patient age was 69.9 years.
Results:   The 1-year, 3-year, and 5-year overall recurrence-free survival rates were 77.0%, 61.3%, and 52.8%, respectively. In multivariate analyses, the multiplicity of bladder tumors, tumor size greater than 3 cm, pathological stage T1, tumor grade G3, and the absence of adjuvant intravesical instillation were independent risk factors for tumor recurrence. Overall, 1710 patients (52.8%) received intravesical instillation; chemotherapy in 1314 (76.8%) and BCG treatment in 396 (23.2%). In patients treated with intravesical chemotherapy in which an anthracycline chemo-agent was used in 90.5% of the cases, multivariate analyses demonstrated that male gender, multiple bladder tumors, a tumor size greater than 3 cm, and pathological stage T1 were associated with tumor recurrence.
Conclusions:   The accumulation and analysis of data from the Japanese National Bladder Cancer Registry made it possible to determine the clinical characteristics, management trends, and survival rates for the period studied. Further study with a dataset created from longer follow-up data would be warranted to analyze tumor progression and disease survival.  相似文献   
57.
Objective:   To report our experience with post-chemotherapy nerve-sparing retroperitoneal lymph node dissection (RPLND) for advanced germ cell tumor (GCT).
Methods:   Between 1994 and 2008, 92 patients with advanced GCT underwent RPLND after multiple treatments with systemic chemotherapy at our institution. A nerve-sparing RPLND was carried out in 78 patients (84.8%; median age 32 years). Of them, 19 had a seminoma and 59 had a non-seminoma.
Results:   Lumbar splanchnic nerves controlling ejaculatory function were macroscopically preserved during RPLND. Bilateral and unilateral lumbar splanchnic nerves were preserved in 40 patients and 38 patients, respectively. Sixty-five patients could be evaluated for ejaculation. Fifty-four patients (83.1%) achieved antegrade ejaculation with a median postoperative interval of 3 months (range: 1–10 months). Twenty-eight patients (28/30: 93.3%) and 26 patients (26/35: 74.3%) undergoing bilateral and unilateral nerve-sparing RPLND had antegrade ejaculation, respectively ( P  = 0.041). Only two patients (2.6%) had mediastinal and retroperitoneal recurrences during a median follow-up of 42 months (range: 1–138 months), respectively. However, these patients were cured by chemotherapy and surgery.
Conclusions:   Post-chemotherapy nerve-sparing RPLND preserves ejaculatory function in the majority of patients with advanced GCT without increasing the risk of local recurrence.  相似文献   
58.
Although laminar screw fixation is often used at the C2 and C7 levels, only few previous case reports have presented the use of laminar screws at the C3-C6 levels. Here, we report a novel fixation method involving the use of practical laminar screws in the subaxial spine. We used laminar screws in the subaxial cervical spine in two cases to prevent vertebral artery injury and in one case to minimize exposure of the lamina. This laminar screw technique was successful in all three cases with adequate spinal rigidity, which was achieved without complications. The use of laminar screws in the subaxial cervical spine is a useful option for posterior fusion of the cervical spine.  相似文献   
59.
A prospective randomized study was conducted to evaluate the efficacy of prophylactic intravesical instillation of pirarubicin (THP) prior to transurethral resection (TUR) of superficial bladder cancer. A total of 63 patients were randomized into two groups, the THP group and the control group. In the THP group, 30 mg of THP dissolved in 50 ml saline was administered 4 times intravesically for 4 consecutive days before TUR. In the control group, no instillation was performed before TUR. The patients were followed by cystoscopy and urinary cytology every 3 months. The non-recurrence rates in the THP group and control group were 54.1% versus 37.6% at 1 year and 40.4% versus 26.8% at 2 years, respectively (P = 0.086). Time to recurrence for tumors larger than 1 cm was significantly longer in the THP group (P = 0.0137). Time to recurrence for single and grade 1+2 tumors tended to be longer in the THP group (P = 0.09, P = 0.079). No significant adverse effects were observed in any patient. Our findings suggest that intravesical THP instillation prior to TUR would be effective for patients with single, low grade lesions larger than 1 cm of superficial bladder cancer.  相似文献   
60.
Background  Prognosis of the patients with pancreatic adenocarcinoma is still poor due to a recurrence, and liver metastasis is a distant metastasis that is foreboded the short survival period. Methods  Between 1999 and 2005, 68 patients for pancreatic adenocarcinoma underwent a pancreaticoduodenectomy (n = 17), a pylorus-preserving pancreaticoduodenectomy (n = 27), distal pancreatectomy (n = 22), or total pancreatectomy (n = 2) with an extensive lymph node dissection. Results  A tumor recurrence occurred to 55 patients (13 of the liver, 21 of the local recurrence, 16 of peritoneal dissemination, three of the lymph node, and two of lung). The low tumor grade and female demonstrated a risk factor for a liver metastasis (P = 0.043, P = 0.031). A logistic regression analysis demonstrated female (P = 0.02) and low tumor grade (P = 0.04) as independent risk factors for recurrence with liver metastasis. The median survival time (MST) was 13.6 months, and MST of patients with a liver metastasis as an initial recurrent site was 13.7 months; the liver metastasis as an initial recurrent site has no impact on the MST after pancreatic resection. Conclusions  We concluded potentially supporting the hypothesis that even patients thought to be at higher risk of liver metastasis may still be given the chance of resection, considering the satisfying survival.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号