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   3882篇
  免费   172篇
  国内免费   41篇
耳鼻咽喉   15篇
儿科学   112篇
妇产科学   59篇
基础医学   580篇
口腔科学   82篇
临床医学   221篇
内科学   859篇
皮肤病学   67篇
神经病学   228篇
特种医学   316篇
外科学   753篇
综合类   47篇
预防医学   136篇
眼科学   26篇
药学   204篇
中国医学   9篇
肿瘤学   381篇
  2023年   22篇
  2022年   31篇
  2021年   71篇
  2020年   53篇
  2019年   51篇
  2018年   50篇
  2017年   43篇
  2016年   63篇
  2015年   67篇
  2014年   101篇
  2013年   112篇
  2012年   186篇
  2011年   223篇
  2010年   150篇
  2009年   115篇
  2008年   200篇
  2007年   244篇
  2006年   213篇
  2005年   244篇
  2004年   247篇
  2003年   240篇
  2002年   238篇
  2001年   115篇
  2000年   119篇
  1999年   100篇
  1998年   75篇
  1997年   60篇
  1996年   48篇
  1995年   44篇
  1994年   32篇
  1993年   44篇
  1992年   66篇
  1991年   47篇
  1990年   51篇
  1989年   54篇
  1988年   41篇
  1987年   27篇
  1986年   28篇
  1985年   27篇
  1984年   24篇
  1983年   15篇
  1982年   9篇
  1981年   12篇
  1980年   9篇
  1979年   16篇
  1978年   6篇
  1973年   6篇
  1969年   8篇
  1968年   7篇
  1967年   6篇
排序方式: 共有4095条查询结果,搜索用时 15 毫秒
1.
Background: For management of bowel obstruction due to colorectal cancer, endoscopic trans‐anal decompression technique has been first reported by Lelcuk et al. in 1986 using balloon dilatation technique. Since then, various types of trans‐anal decompression tubes have been clinically used for patients suffering from left side obstructing colorectal cancer as an emergent decompressing device. At present, two types of trans‐anal ileus tube (trans‐anal decompression tube) have been available for clinical use, but they have two main problems that are late colon perforations caused by the tip of the tube and tube obstruction by stool. Methods: Analysis on three late colon perforations experienced with the use of conventional devices drew possible improvements to make a trans‐anal ileus tube less harmful. To overcome the pitfalls inherent to conventional tubes, the author has developed an improved trans‐anal ileus tube with a balloon installed at the very end of the tube (‘balloon‐tipped type’) made of silicone, measuring 1200 or 1700 mm in total length and 22 Fr in outer diameter. It has been used for 12 cases with obstructing colorectal cancer etc. and its outcomes were compared with those obtained by the use of conventional trans‐anal ileus tube. Results: No late perforations have been encountered, but tube obstruction did occur in one of 12 cases. Conclusion: The new trans‐anal ileus tube with a balloon installed at the tip of ileus tube is considered to be safer and especially effective in preventing late colon perforation and tube obstruction.  相似文献   
2.
A 69-year-old man was admitted to our kidney center with endstage renal failure. We started intermittent peritoneal dialysis immediately because of severe azotemia, hyperkalemia, and metabolic acidosis. Two weeks after admission, he developed uremic pericarditis with frequent ventricular premature contractions and supraventricular premature contractions. The intermittent peritoneal dialysis was then replaced by intensive hemodialysis, and oral administration of 300 mg/d of cibenzoline was started. Four days later, he developed thirst, weakness, and dyspnea due to respiratory muscular paralysis. We initiated respiratory support with a respirator because analysis of his blood gases revealed marked hypercapnia and hypoxia. He also developed hypoglycemia and prolonged PQ and QRS intervals on the electrocardiogram, which we believed were due to cibenzoline intoxication; we discontinued the cibenzoline immediately. All symptoms improved, and he was extubated 5 days later. After 2 months, his pericardial effusion disappeared. He now continues maintenance hemodialysis as an outpatient. We suspect that the cibenzoline induced the respiratory muscular paralysis for 2 reasons: 1) the patient experienced the respiratory muscular paralysis, at the same time he also experienced thirst, weakness, hypoglycemia, and prolonged PQ and QRS intervals on electrocardiogram, and all of these symptoms improved after the discontinuation of cibenzoline, and 2) his plasma concentration of cibenzoline became remarkably elevated, to 20 times above the standard therapeutic level. This patient's clinical course indicates that hemodialysis might be superior to intermittent peritoneal dialysis for treatment of cibenzoline intoxication.  相似文献   
3.
A left ventricular rupture due to embolic myocardial infarction is extremely rare. A 72-year-old woman developed an acute embolic myocardial infarction and mitral regurgitation due to infective endocarditis. Two days after the infarction, a left ventricular free wall rupture occurred after transesophageal echo examination. She received an epicardial patch and mitral valve replacement. Perioperatively, an intra-aortic balloon pump and long-term antibiotics were used. The postoperative course was uneventful, and she is doing well 10 months after surgery.  相似文献   
4.
5.
To elucidate the mechanisms of the intracellular signal transduction elicited with bradykinin in NG108-15 neuroblastoma x glioma hybrid cells, we examined the activation of Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) by bradykinin stimulation. When the extract of NG108-15 cells was immunoprecipitated with the affinity-purified antibody to brain CaM kinase II, a 50-kDa protein in the immunoprecipitate mainly became autophosphorylated in a Ca2+/calmodulin-dependent manner. The results suggest that the 50-kDa protein is the subunit of CaM kinase II in NG108-15 cells. The Ca2+/calmodulin-independent activity (autonomous activity) of the enzyme increased twice within 10 s by stimulation with 1 microM bradykinin in the cells. The increase in the autonomous activity of the enzyme had two phases: the transient early-peak phase and the long late-plateau phase. The former was abolished by the pretreatment of the cells with 10 mM caffeine or 20 microM BAPTA-AM, and the latter was abolished by the removal of the extracellular Ca2+ with 1 mM EGTA or by the pretreatment with 1 microM nifedipine. Stimulation of 32P-labeled NG108-15 cells with 1 microM bradykinin increased the autophosphorylation of CaM kinase II and this increase was abolished by pretreatment with caffeine or BAPTA-AM. These results suggest that CaM kinase II is activated via the inositol phospholipid signaling pathway induced with bradykinin in NG108-15 cells.  相似文献   
6.
A patient with a recurrent tumor in the trachea adjacent to the right main bronchus was treated by surgical resection 19 months after undergoing surgery for the primary cancer. The patient had previously undergone right upper lobectomy for T1N0M0 stage I squamous cell carcinoma. A carinal resection was performed which included 4 rings of the trachea, 2 rings of the righ main bronchus, and 1 ring of the left main bronchus. Reconstruction consisted of an end-to-end anastomosis of the trachea and left main bronchus, and an end-to-side anastomosis of the right and left main bronchi. The postoperative course was uneventful, and at present the patient is healthy 12 months following reoperation.  相似文献   
7.
Forty-nine pathologically proven gallbladder lesions were evaluated in 45 patients using dynamic MRI with a spoiled gradient pulse sequence (SPGR), to access the ability of this technique to differentiate benign from malignant gallbladder lesions. The studies were reviewed retrospectively. Signal intensity of the lesions were measured. Twenty-one malignant and 28 benign lesions were classified into three categories: polypoid, diffuse wall thickening, and exophytic. Early and delayed enhancement patterns were evaluated. For the polypoid masses, malignant lesions (n = 9) demonstrated early and prolonged enhancements, whereas benign lesions (n = 14) had early enhancement with subsequent washout (P < .05). For diffuse gallbladder wall thickening, malignant lesions (n = 6) demonstrated early and prolonged enhancement and benign lesions (n = 14) showed relatively slow, prolonged enhancement (P < .05). The exophytic masses (n = 6) all were malignant and demonstrated early and prolonged enhancement. Dynamic MRI can help differentiate benign from malignant gallbladder lesions.  相似文献   
8.
Late Effects of Childhood Acute Leukemia and Its Treatment   总被引:1,自引:0,他引:1  
Late effects of childhood acute leukemia and its treatment were studied in 766 patients (684 ALL, 73 ANLL, and 9 others) in Japan who had remained in remission for more than 1 year after their first complete remission. Delayed adverse sequelae involve a wide variety of organs and their functions. Short stature was present in 2.61%, obesity in 3.79%, abnormalities of growth hormone secretion in 1.5%, delayed secondary sex characteristics in 1.5% of males and 0.6% of females, motor disturbances in 1.17%, sensory disturbances in 0.91%, intellectual and learning disabilities in 2.48%, abnormal findings in routine neurologic examinations in 1.31%, EEG abnormalities in 4.30%, brain CT abnormalities in 5.09% and cardiac dysfunction in 1.07%. Various other disorders were seen in 20 patients. Many of these delayed adverse sequelae are caused by or related to central nervous system prophylaxis and systemic combination chemotherapy. The results suggest that it is needed to improve therapeutic methods through the stratification of patients by risk factors and detailed analysis of prognostic factors. Moreover it is important to render medical and psychosocial support to long-term survivors of childhood leukemia through interactions between the patient, parents and medical staff.  相似文献   
9.
A 80-year old man was referred to our hospital because of an elevation of serum amylase level. Diffuse enlargement of the pancreas was detected by abdominal computed tomography, and also diffuse narrowing of the main pancreatic duct was revealed using endoscopic retrograde cholangiopancreatography. The serum level of IgG was elevated to 3450mg/dl. Besides, on the 10th hospital day, petechia developed and the platelet level decreased to 1.5 x 10(4)/microl. The platelet-associated IgG, antiplatelet antibody and antinuclear antibody in serum were positive. The levels of serum complements were low. From all these findings the patient was diagnosed as autoimmune pancreatitis complicated with immune thrombocytopenia. The treatment with prednisolone was started, which was effective on each disease. The medication was suspended a year ago, and so far there is no data suggesting the recurrence of autoimmune pancreatitis or immune thrombocytopenia.  相似文献   
10.
The cardiac myosin light chain I (LCI) is one of the cardiac muscle structural proteins. A sensitive immunoradiometric assay kit for LCI by using LCI monoclonal antibodies is developed. We estimated LCI in the patients with Duchenne muscular dystrophy (DMD) and Kugelberg-Welander disease (KW). The results suggested that LCI has close relationships with the functional disturbances of skeletal muscles, especially disturbances of pulmonary ventilation. Therefore we studied properties and localizations of LCI in the skeletal muscles by Western blotting and immunohistochemical methods. In Western blotting method LCI monoclonal antibodies have a band of 27 KD proteins of skeletal muscles. LCI has also found to be localized in type 1 fibers in frozen sections of biopsied of human skeletal muscles. LCI was measured from 47 patients with DMD and 8 patients with KW. The average serum LCI levels in the patients with DMD were 11.79 ng/dl and its levels in the patients with KW were in the normal range (under 2.5 ng/dl). Among 12 patients receiving negative pressure chest respirator, the levels of LCI were also under 2.5 ng/dl. Serum LCI decreased with increasing age and reduced physical activity. The levels of LCI has obvious positive correlations with CK and myoglobin. These results suggested that the measurements of serum LCI are useful as one of the markers of disease severity and the determination of suitable time of using respirator.  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