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   906篇
  免费   50篇
  国内免费   1篇
耳鼻咽喉   20篇
儿科学   54篇
妇产科学   7篇
基础医学   88篇
口腔科学   8篇
临床医学   57篇
内科学   235篇
皮肤病学   15篇
神经病学   72篇
特种医学   50篇
外科学   143篇
综合类   8篇
预防医学   77篇
眼科学   5篇
药学   57篇
中国医学   1篇
肿瘤学   60篇
  2023年   6篇
  2022年   12篇
  2021年   16篇
  2020年   25篇
  2019年   11篇
  2018年   18篇
  2017年   17篇
  2016年   21篇
  2015年   14篇
  2014年   19篇
  2013年   26篇
  2012年   33篇
  2011年   30篇
  2010年   34篇
  2009年   29篇
  2008年   34篇
  2007年   46篇
  2006年   31篇
  2005年   41篇
  2004年   28篇
  2003年   35篇
  2002年   27篇
  2001年   24篇
  2000年   33篇
  1999年   24篇
  1998年   18篇
  1997年   17篇
  1996年   12篇
  1995年   6篇
  1994年   9篇
  1993年   10篇
  1992年   22篇
  1991年   23篇
  1990年   12篇
  1989年   22篇
  1988年   17篇
  1987年   13篇
  1986年   15篇
  1985年   11篇
  1984年   14篇
  1983年   10篇
  1982年   9篇
  1979年   12篇
  1978年   10篇
  1977年   4篇
  1976年   17篇
  1975年   8篇
  1973年   5篇
  1969年   5篇
  1967年   5篇
排序方式: 共有957条查询结果,搜索用时 15 毫秒
1.
2.
Several attempts have been made to enhance doxorubicin (DOXO) concentrations in tumour cells by drug conjugation with human albumin (HSA). HSA-DOXO has the drawback of causing DOXO accumulation in spleen and bone marrow, with a consequent leucopoenia not produced when lactose molecules are coupled to the carrier protein. In the present experiments we demonstrated that the effect of HSA lactosamination is not a consequence of a more rapid disappearance from the bloodstream of the lactosaminated conjugate (L-HSA-DOXO), which is rapidly internalized by the liver through the asialoglycoprotein receptor, but is due to a hindered uptake by spleen and bone marrow cells caused by the coupled lactose molecules. Experiments in vitro showed that HSA-DOXO produced an inhibition of murine macrophage proliferation not caused by L-HSA-DOXO. This result can be explained by higher amounts of the former conjugate entering in these cells and suggests macrophages as the cell type responsible for the spleen and bone marrow internalization of HSA-DOXO hindered by lactose coupling. Importantly, lactosamination of HSA did not reduce the marked uptake of HSA-DOXO by chemically induced rat hepatocellular carcinoma. L-HSA-DOXO, by avoiding DOXO accumulation in bone marrow is an attractive candidate for clinical trials against tumors which were found to actively internalize this conjugate in laboratory animals, such as hepatocellular carcinoma.  相似文献   
3.
Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
4.
OBJECTIVE: The aim of this paper was to describe our surgical technique for the treatment of nasal septal perforations. STUDY AND DESIGN: We studied 31 patients with nasal septal perforation treated with an endoscope-assisted technique, based on a bilateral dissection of monopedicled mucosal flaps from the nasal fossa floor, sutured at the edge of the perforation previously unstuck, without any graft interposed between the two mucosal layers. RESULTS: In our experience with 31 patients, the use of this technique led to the persistent closing (with follow-up for at least one year) of 96.3% of the perforations smaller than 3 cm. CONCLUSIONS: Our technique has the advantage of an endonasal approach, without any external incision, and the use of monopedicled flaps from the nasal fossa floor without any graft interposition, avoiding any other surgical procedure and morbidity in the donor site of the graft. The use of nasal endoscopy permits superior precision in all surgical steps. SIGNIFICANCE: The high success rate in perforations smaller than 3 cm seems to confirm the effectiveness of this technique.  相似文献   
5.
We report the results of magnesium sulphate (MgSO4) infusion in 10 patients with different ventricular arrhythmias: 6 torsade de pointes (2 with total A-V block, 1 with acute myocardial infarction and 3 with lengthening of the Q-Tc due to antiarrhythmic and/or diuretic treatment), 1 bidirectional ventricular tachycardia (on chronic treatment with digoxin (0.5 mg/day) and diuretics), and 3 polymorphic ventricular ectopic beats plus ventricular tachycardia runs (2 with hypertensive and 1 with ischemic cardiomyopathy). MgSO4 in normal saline was given at low rate (50 mg/min) and continued 2 hours after disappearance of arrhythmia, and the infusion was repeated at the same rate for 60-90 min twice daily for the next 3-4 days. In all patients the drug was effective and no side effects were observed. The heart rate and Q-Tc interval remained unchanged from baseline values. Serum creatinine concentration was normal. Serum Mg++, 60 minutes after the beginning of the infusion, was comparable to control values in all the patients, except 2 with hypomagnesemia. Finally, we can conclude that MgSO4 is an useful therapeutic tool for the treatment of various ventricular tachycardias.  相似文献   
6.
7.
The aim of the study was to evaluate the effectiveness of transabdominal wedge colpectomy as surgical treatment for cystocele. One hundred and sixty-three women with either first or second-degree cystocele (Beecham classification), rectocele and concomitant stress urinary incontinence or benign pelvic masses were submitted for a combined operation. Transabdominal repair of the cystocele was performed by wedge colpectomy employing two different absorbable sutures, Vicryl and PDS. The choice of suture was not random but depended on the period at which surgery was performed. Data obtained were analyzed with Student’st-test and Fisher’s exact test. The cystocele cure rate was 90.2% (110 out of 122) at 3-year follow-up and was significantly associated with the preoperative degree, being 95.5% and 76.5% in first and in second degree, respectively (P=0.003). At 1-year follow-up the cure rate was significantly associated with the type of the suture employed (P=0.01). At 2-year follow-up rectocele cure rate was 97.2% and vaginal vault prolapse appeared in 3.5% of cases. Stress urinary incontinence relapsed in 10% of patients after Burch colposuspension. After the operation 94.1% of the women declared normal coitus. In the present series wedge colpectomy was found to be effective in repairing first-degree cystocele, whereas a high incidence of relapse was observed when second-degree cystocele was present preoperatively. The suture material employed influenced the cure rate. EDITORIAL COMMENT: Wedge colpectomy of the anterior vaginal wall has been described by Weinstein and Roberts (1949), Macer (1978) and Drutz (1991) as a means of abdominally correcting anterior vaginal wall relaxation. Although the present authors did not find as high a success rate with the procedure as the previous investigators, they do show that an abdominal approach to cystocele repair is feasible. There are instances when such an approach would be advantageous to avoid repositioning for a vaginal anterior wall repair. The danger of abdominal anterior wedge colpectomy lies in the dissection of the bladder base from the underlying vaginal wall. Dissection in this area must proceed carefully to avoid trauma to the bladder, ureters and, more distally, to the urethrovesical junction. Performed carefully, with attention directed at avoiding these structures, the abdominal wedge colpectomy is a potentially useful procedure to add to the armamentarium of the urogynecologic surgeon.  相似文献   
8.
The concomitance of horseshoe kidney and abdominal aortic aneurysm is rare but represents an interesting challenge for vascular surgeons. The trouble is greater if the diagnosis is formulated intraoperatively and specially if it is an emergency operation for aortic rupture or fissuration. The surgeon's aim is to get to the aneurysm collar without damaging the kidney, the renal arteries or the urinary tract that often have an anomalous development. The authors make a review of the literature and describe three cases occurred out of 2558 prosthetic reconstructions due to abdominal aortic aneurysm.  相似文献   
9.
PURPOSETo define MR accuracy in the evaluation of the T stages of tumors of the tongue and floor of the mouth.METHODSFifty-two patients affected by squamous cell carcinoma were studied with a superconductive system at 1.5 T. The study was performed with spin-echo T1- and T2-weighted images before contrast and short spin-echo T1-weighted and gradient-echo sequences after gadopentetate dimeglumine administration. The results obtained with MR were compared with pathologic data.RESULTSGood correlation of T stages (TNM system) was obtained in 45 of 52 cases. MR did not show four superficial lesions. In one case, infiltration of the cortical bone of the mandible was not demonstrated (MR, T2; pathologic, T4), and in another the lesion was classified as T2 instead of T3, as it was pathologically. One lesion was classified as T4 on MR because of infiltration of the alveolar ridge but was classified as T2 at surgery. In 46 patients who underwent surgery, the accuracy of MR was excellent for predicting the relationship of tumor to midline and oral floor musculature. The results obtained with gadopentetate dimeglumine were better than those obtained in noncontrast studies in 32 (62%) of 53 cases.CONCLUSIONMR showed high accuracy in the study of tumors of the tongue and floor of the mouth.  相似文献   
10.
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