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   19354篇
  免费   979篇
  国内免费   90篇
耳鼻咽喉   88篇
儿科学   269篇
妇产科学   228篇
基础医学   2517篇
口腔科学   527篇
临床医学   1316篇
内科学   4572篇
皮肤病学   268篇
神经病学   1687篇
特种医学   977篇
外科学   3903篇
综合类   73篇
预防医学   489篇
眼科学   360篇
药学   1459篇
中国医学   46篇
肿瘤学   1644篇
  2022年   156篇
  2021年   369篇
  2020年   160篇
  2019年   246篇
  2018年   362篇
  2017年   274篇
  2016年   304篇
  2015年   307篇
  2014年   416篇
  2013年   544篇
  2012年   825篇
  2011年   940篇
  2010年   485篇
  2009年   424篇
  2008年   771篇
  2007年   908篇
  2006年   935篇
  2005年   888篇
  2004年   823篇
  2003年   802篇
  2002年   803篇
  2001年   776篇
  2000年   789篇
  1999年   725篇
  1998年   237篇
  1997年   201篇
  1996年   162篇
  1995年   136篇
  1994年   131篇
  1993年   145篇
  1992年   524篇
  1991年   464篇
  1990年   435篇
  1989年   430篇
  1988年   416篇
  1987年   356篇
  1986年   355篇
  1985年   356篇
  1984年   200篇
  1983年   165篇
  1982年   83篇
  1981年   81篇
  1979年   169篇
  1978年   124篇
  1977年   91篇
  1974年   124篇
  1973年   113篇
  1972年   81篇
  1970年   83篇
  1969年   101篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
11.
In lung cancer patients, hypercalcemia is a fairly common metabolic problem associated with malignancy. However, the occurrence of hypercalcemia in lung cancer patients means an ominous prognostic sign. As hypercalcemia often causes early death, quick diagnosis and treatment for hypercalcemia are required. A 69-year-old woman was admitted to our hospital with anorexia caused by hypercalcemia. On admission, serum level of PTH was elevated and PTHrP was normal. From the results of CT findings and transbronchial lung biopsy, the cause of the hypercalcemia was determined as lung cancer incidentally complicated with primary hyperparathyroidism. First, serum calcium level was returned to normal through hydration with saline and bisphosphonates. Next, left hemithyroidectomy for primary hyperparathyroidism was performed. Histologically, the tumor was diagnosed as parathyroid adenoma. Fifteen days later, left lower lobectomy for primary lung cancer was performed under a video-assisted thoracoscopic approach. Histologically, the tumor was diagnosed as a moderately differentiated adenocarcinoma. Four years and three months after the operation, the patient is alive and well with no sign of recurrence. When a lung cancer patient is complicated with hypercalcemia, we need to consider that primary hyperparathyroidism is a possible cause of the hypercalcemia.  相似文献   
12.
We report a case of mediastinal liposarcoma, recurrent after 20 years. A 58-year-old man who presented with dyspnea on exertion was found to have a large mediastinal tumor in chest computed tomography (CT), and he was referred to our hospital. He had undergone an extirpation of a mediastinal liposarcoma about 20 years earlier, and we suspected its recurrence. Because the tumor was very large, it was removed in two stages. Histologically it was diagnosed as a recurrence of the previous well-differentiated liposarcoma. Although liposarcoma is one of the most common soft-tissue sarcomas in adults, a mediastinal liposarcoma is rare. Because the recurrence rate is very high, it is necessary to follow up carefully over a long term.  相似文献   
13.
BACKGROUND: Although many histopathologic factors in squamous cell carcinoma of the tongue predict the prognosis, the major predictive factors have not been identified clearly. This study analyzed the prognostic value of the histologic grade at the deep invasive front of tongue squamous cell carcinoma. METHODS: The clinicopathologic features of 124 consecutive patients seen between January 1985 and December 1999 with previously untreated squamous cell carcinoma of the tongue were reviewed. Their mean age was 58.5 years (range: 23-90) and the male-female ratio was 1.8: 1 (79 men and 45 women). There were 41, 40, 30, and 13 cases at stage I to stage IV, respectively. The clinicopathologic factors, especially the histologic grade at the deep invasive front (invasive front grade, IFG), were analyzed to determine factors predicting prognosis. RESULTS: The 5-year disease-free survival rate of the patients treated with curative aim only was 66.7%. Clinicopathologic factors significantly associated with the prognosis were T classification, tumor size, stage classification, tumor depth, macroscopic appearance, cervical lymph node metastasis (nodal metastasis), microvascular invasion, and IFG. In a multivariate analysis, patients with tumor depth >/=4 mm, IFG >/=8 points, and nodal metastasis had a reduced disease-free survival and IFG >/=11 points had a predictive value for nodal metastasis (odds ratio: 7.34; P = 0.0019). CONCLUSION: This study found that a high IFG malignancy score had a high prognostic value for squamous cell carcinoma of the tongue.  相似文献   
14.
The effects of halothane (0.2%, 0.5%, and 1.0%) on the spinal dorsal horn wide dynamic range (WDR) neuronal activity was studied in either spinal cord intact or spinal transected cats. Extracellular activity was recorded in the dorsal horn from single WDR neurons responding to noxious and non-noxious stimuli applied to the cutaneous receptive fields on the left hind foot pads of intact or decerebrate, spinal cord transected (L 1-2) cats. When 10 micrograms of bradykinin was injected into the femoral artery ipsilateral to the recording site as the noxious test stimulus in the spinal cat, all of 7 WDR neurons gave excitatory responses which were not depressed by 0.2% and 0.5% halothane but were depressed significantly by 1.0%. On the other hand, when the injection of 10 micrograms of bradykinin into the femoral artery ipsilateral to the recording site was used in the intact cat, 7 of 14 WDR neurons (50%) gave excitatory responses, which were not depressed by 0.2% halothane but were significantly depressed by 0.5% and 1.0% halothane, and 7 of 14 WDR neurons (50%) gave inhibitory responses, which were significantly depressed by 0.2%, 0.5%, and 1.0% halothane. We have found that halothane reduces the excitation as well as the inhibition of dorsal horn WDR neuronal activity induced by bradykinin injection.  相似文献   
15.
AIMS: A rare case of the insulin autoimmune syndrome (IAS) accompanied by insulin receptor anomaly is reported. METHODS: Antibodies to insulin and insulin receptor were determined in the patient with severe hypoglycaemia before and after the treatment with prednisolone. RESULTS: Titers of antibody to insulin and insulin receptors were 73.0% and 41.5%, respectively. Drug-induced lymphocyte stimulation tests were all negative for the suspicious drugs. Her HLA-DR was DRB1*0403/04051. Following steroid therapy, the formation of antibodies was suppressed and alleviated her symptoms. Scatchard analysis yielded findings specific to polyclonal antibodies. CONCLUSIONS: The changes in autoantibodies resulted in alleviation of the hypoglycemic symptoms as a result of steroid therapy.  相似文献   
16.
A 44-year-old women developed marked myopathy one year earlier, when she was treated with intravenous prednisolone for acute severe exacerbation of ulcerative colitis. When she was admitted to our hospital for another severe exacerbation, intravenous cyclosporine A was administered as monotherapy because she could not tolerate corticosteroid. The treatment was successful and she obtained complete remission. Cyclosporine A monotherapy is considered to be a valuable alternative to proctocolectomy for severe ulcerative colitis patients who cannot tolerate corticosteroid.  相似文献   
17.
We describe a case of 41-year-old Japanese man with Crohn's ileocolitis and cytomegalovirus infection, confirmed by histology of ileal ulcers. Although his colonoscopic and radiological features resembled those of intestinal tuberculosis, granulomas of typical Crohn's disease were evident on histology of biopsy specimens taken from the duodenum and colon. The lesions remain unchanged even after 1.5 years by oral administration of salazosulphapyridine 3g daily.  相似文献   
18.
OBJECTIVE: It is well described that unilateral pelviureteric junction obstruction (PUJO) is a benign condition, because the dilatation resolves spontaneously and the function does not decrease in most of the kidneys. However, there is exceptional PUJO that requires emergent treatment in neonatal periods. The aim of this article is to report the urological emergency and management in neonates with PUJO. MATERIALS AND METHODS: Nine children (seven boys and two girls) with PUJO who underwent neonatal emergent treatment during the last 13 years were reviewed. Renal function was evaluated according to decay curve of serum creatinine (SCr) levels corresponding to gestational age (GA) at delivery. Physical examination, ultrasonographic monitoring, and chest and abdominal plain radiographs were repeated in each neonate. RESULTS: Eight patients were detected prenatally. In five patients, multicystic dysplastic kidney (MCDK) was demonstrated on the contralateral side. Three patients underwent percutaneous puncture of fetal hydronephrosis. Decrease of amniotic fluid was evident in three fetuses. Indications for emergent treatment included mass effect from hydronephrosis in three patients, renal dysfunction in five, and severe urinary tract infection in one. During neonatal periods, a percutaneous nephrostomy tube was placed in seven, and open nephrostomy in one with anorectal malformation. Repeated punctures of the dilated renal pelvis were done in one patient. Renal function after pyeloplasty was stable in eight patients, while it was moderately decreased in one who was associated with oligohydramnios in utero. CONCLUSION: Indications for emergent treatment in neonates with PUJO included mass effect from giant hydronephrosis, renal dysfunction and severe urinary tract infection. At birth, respiratory and circulatory conditions must first be stabilized. In neonates with hydronephrosis of the solitary kidney or severe bilateral PUJO, serial SCr should be monitored to evaluate renal function. Decrease of amniotic fluid suggested renal functional compromise that would not recover after urological management.  相似文献   
19.
OBJECTIVES: We reviewed the results of surgical treatment for children with ureterocele, especially addressing the importance of the lower urinary tract reconstruction. METHODS: We present medical records of 91 children with ureterocele (31 with the intravesical type, and 60 with the ectopic type) treated during the last 14 years. As the initial treatment, we carried out transurethral incision of the ureterocele (TUI). In patients with persistent reflux, breakthrough urinary tract infection (UTI), or signs of bladder outlet obstruction due to a collapsed cele wall, we recommended that patients undergo lower urinary tract reconstruction irrespective of the renal function involved in ureterocele. The average follow-up period was 5 years (ranging 1 year and 6 months to 14 years). RESULTS: Transurethral incision of the ureterocele was carried out as the initial treatment on 68 patients (75%). A total of 34 patients (21 intravesical [68%] and 13 ectopic [22%]) were followed medically after TUI alone. Reconstruction of the lower urinary tract was carried out in 59 patients (65%). Nephroureterectomy combined with bladder level reconstruction was carried out in four children with single system and non-functioning kidney. Follow-up voiding cystourethrography showed that only one girl had reflux, which disappeared after the first follow-up examination. Postoperative UTI occurred in 12 patients (20%) with ectopic ureterocele. Voiding dysfunction was suspected in eight patients. CONCLUSION: We believe that the primary objective for patients with ureterocele, especially of the ectopic type, is to reconstruct the original pathology of the lower urinary tract that may give rise to reflux, obstruction, or abnormalities of urination. Although surgery at the bladder level can be challenging, the lower urinary tract reconstruction successfully corrects the vesicoureteral reflux and bladder outlet pathology under a cosmetically acceptable incision.  相似文献   
20.
The case of a 75-year-old man with three synchronous carcinomas of the lung (large cell carcinoma, adenocarcinoma, and small cell carcinoma) is reported. This is the eighth well-documented case report in the literature; however, our case is the first to be reported with the newly described histological combination.  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