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   897篇
  免费   59篇
  国内免费   4篇
耳鼻咽喉   9篇
儿科学   13篇
妇产科学   7篇
基础医学   111篇
口腔科学   27篇
临床医学   46篇
内科学   229篇
皮肤病学   9篇
神经病学   106篇
特种医学   29篇
外科学   174篇
综合类   1篇
预防医学   12篇
眼科学   54篇
药学   45篇
肿瘤学   88篇
  2023年   1篇
  2022年   3篇
  2021年   15篇
  2020年   10篇
  2019年   11篇
  2018年   23篇
  2017年   9篇
  2016年   18篇
  2015年   24篇
  2014年   27篇
  2013年   39篇
  2012年   82篇
  2011年   57篇
  2010年   41篇
  2009年   46篇
  2008年   62篇
  2007年   56篇
  2006年   54篇
  2005年   52篇
  2004年   52篇
  2003年   51篇
  2002年   44篇
  2001年   18篇
  2000年   19篇
  1999年   15篇
  1998年   14篇
  1997年   9篇
  1996年   5篇
  1995年   3篇
  1994年   2篇
  1993年   1篇
  1992年   12篇
  1991年   11篇
  1990年   8篇
  1989年   4篇
  1988年   8篇
  1987年   11篇
  1986年   5篇
  1985年   2篇
  1984年   6篇
  1983年   2篇
  1982年   1篇
  1981年   4篇
  1979年   6篇
  1977年   4篇
  1976年   2篇
  1975年   2篇
  1974年   5篇
  1973年   3篇
  1959年   1篇
排序方式: 共有960条查询结果,搜索用时 500 毫秒
91.
92.
This study aimed to examine the close correlation betweencomplicated febrile convulsions (CFC) and medial temporal lobe epilepsy and to delineate characteristics of temporal lobe epilepsy with CFC.Patients with temporal lobe epilepsy were divided into those with aprior episode of CFC (n=52), those with febrile convulsions other thanCFC, and those witout either (n=345). Clinical constellations, neuroimaging, drug resistance, and effects of temporal lobectomy of thethree groups were compared. A close association between CFC andtemporal lobe epilepsy was confirmed. The salient features of temporallobe epilepsy with CFC were early age at onset of habitual seizures(about 10 years), the predominance of autonomic auras, and a highincidence of MRI evidence of unilateral medial temporal sclerosis.Patients with temporal lobe epilepsy with prior CFC had an excellentoutcome after surgery, by contrast with an unfavourable response todrug therapy. The surgical results were discouraging in patients withtemporal lobe epilepsy without history of any febrile convulsions andwithout solid brain tumours. These results indicate surgicalintervention as the choice of therapy in a substantial number ofpatients with temporal lobe epilepsy with a history of CFC.

  相似文献   
93.
BACKGROUND: Renal failure (RF) is a well-recognized complication of aortic aneurysms (AA) although its incidence has been poorly documented previously. The purpose of this study is to examine the incidence of RF in patients with AA and prognosis of AA patients with RF. METHODS: Renal function, complications and prognosis of AA patients with RF were retrospectively reviewed in 350 AA patients (median age 69.8+/-10.7 years) in the International Medical Center of Japan from 1989 to 1999. RESULTS: Among 350 patients with AA, 90 patients (25.7%) had chronic renal failure (CRF) at the initiation of follow-up. The number of CRF patients increased to 117 (33.4%) at 30 months of follow-up. Forty-four out of 160 patients (27.5%) who had aortic surgery developed postoperative acute renal failure (ARF). Stepwise logistic regression analysis revealed that age (>or=65 years), hypertension and multiple aneurysms were independent risk factors for CRF, whereas dissecting aneurysms, preoperative serum creatinine (sCr) levels and duration of surgery were independent risk factors for postoperative ARF in AA patients. In the 5-year follow-up of AA patients with CRF, the mean slopes of 1/serum-creatinine did not significantly differ between conservative treatment and surgical treatment. The survival rates were 49.5% in the conservative treatment group and 67.3% in the surgical treatment group. CONCLUSION: Our data suggest that the management of renal function including blood pressure from an early stage in AA patients is important since CRF is highly prevalent in AA patients and affects their prognosis and mortality.  相似文献   
94.
BACKGROUND: Alterations of human patched (ptc) homolog have been proven to be responsible for basal cell nevus syndrome (BCNS). Mandibular cysts in heterozygous ptc knockout mouse (ptc+/- mouse) were microradiologically, histologically, immunohistochemically, and genetically examined to investigate the possible role of the ptc gene and its associates in the jaw cysts. METHODS: The mandibular bones were prepared from 63 ptc+/- mice and 6 ptc+/+ mice. Soft X-ray radiographs and histological sections were examined for detection of the presence of mandibular cysts. The mandibular cysts were immunohistochemically investigated using anti-ptc, shh, and smo antibodies. PCR analysis of loss of heterozygosity (LOH) of ptc was performed in genomic DNA from the mandibular cysts. RESULTS: Six ptc+/+ mice showed no pathologic change in any examinations. Microradiologically, ptc+/- mice did not show any apparent lesion. Mandibular cysts were often multiple, and were histologically detected in the alveolar bones or periodontal ligaments of the molars in 16 (25.4%) ptc+/- mice. The mandibular cysts were lined by thin parakeratotic stratified squamous epithelium and contained keratinized materials. Immunohistochemical examination showed sonic hedgehog (shh) protein mainly in cyst lining epithelium, and ptc and smoothened (smo) proteins in cyst lining epithelium, and surrounding fibrous connective tissue. Expression of ptc protein in the cyst lining epithelium tended to be weak as compared with incisor enamel organs and gingival stratified squamous epithelium. LOH of the ptc gene couldn't be found in lining epithelium of mandibular cysts in any ptc+/- mice. CONCLUSIONS: Ptc+/- mouse is a useful model of BCNS from the standpoint of occurrence of jaw cysts, and downregulation of ptc protein in cyst lining epithelium caused by gene targeting would be associated with formation of jaw cysts in ptc+/- mice.  相似文献   
95.
A 17-year-old female admitted for cleft palate surgery was referred for further evaluation of her cardiac condition. The patient had been diagnosed as dextrocardia at birth, without any cardiac murmurs. She has led a normal life. The apical impulse was felt at the fifth intercostal space at the right mid-clavicular line. The ECG and chest x-rays were strongly suggestive of corrected transposition of the great arteries (CTGA) with situs inversus visceralis. Findings of the two-dimensional and Dopplar echocardiograms showed CTGA with a mild morphologic tricuspid regurgitation without any other complicated cardiac anomalies. In the Japanese literature, 36 CTGA patients without associated cardiac defects have been reported. Of these, four patients revealed dextrocardia. To our knowledge, our patient is the first reported adult case without any cardiac defects, only minimal tricuspid regurgitation, situs inversus totalis and cleft palate.  相似文献   
96.
Specific heating of magnetic particles in radiofrequency (RF) capacitive hyperthermia and its hyper-thermic effect were investigated in an in vivo study. Magnetite cationic liposomes (MCLs) were injected into a rat tumor on the femur and 8 MHz-RF capacitive heating was applied to the rat under'mild heating' conditions. Although the input power of RF capacitive heating was low under the same power conditions, the MCLs-injected tumor was heated over 43°C, whereas it was only heated to 41°C in the case of the rats not injected with MCLs. A necrotic area in the tumor was observed in the heated rats. From the results of histological observation of the removed tissue, the necrotic area in the MCLs-injected tumor was wider than that in MCLs-free tumor. Complete tumor suppression was observed in 71% (5/7) of MCLs-injected rats, and the hyperthermic effect was greatly improved by the MCLs.  相似文献   
97.
Objective: The aim of the present study was to assess the usefulness of endoscopic ultrasonography (EUS) for evaluating the efficacy of neoadjuvant therapy for advanced esophageal carcinoma based on the Response Evaluation Criteria in Solid Tumors (RECIST). Patients and Methods: Sixty‐two patients with advanced esophageal carcinoma underwent surgical resection after neoadjuvant therapy. The maximal tumor thickness was measured by EUS before and after neoadjuvant therapy, and the percent reduction was compared with the pathological response. Based on the RECIST, PD‐SD (progressive disease‐stable disease) was defined as < 30% reduction of tumor thickness on EUS, PR (partial response) as ≥ 30% reduction of tumor thickness, and CR (complete response) as no detectable tumor (100%). Results: The percent reduction of the thickness of Grade 0–1, Grade 2 and Grade 3 tumor was 11.5 ± 21.0%, 48.2 ± 17.0% and 74.9 ± 21.1%, respectively. There were significant differences in the extent of reduction among the three groups. Based on the RECIST, 80% of Grade 0–1 cases, 91% of Grade 2 cases and 22% of Grade 3 cases were PD‐SD, PR, and CR according to EUS, respectively. EUS correctly identified 80% of non‐responders and 94% of responders. Conclusions: The percentage reduction of tumor thickness on EUS closely reflected the pathological evaluation. EUS evaluation based on the RECIST seems to be useful for monitoring neoadjuvant therapy in patients with esophageal carcinoma.  相似文献   
98.
Small cell lung cancer (SCLC) is a fatal malignancy due to its propensity to metastasize widely and to reoccur after chemotherapy in a drug-resistant form. While most SCLC cell lines are anchorage independent for growth, laminin induced the attachment of five of six SCLC cell lines tested (NCI-N417, NCI-H345, NCI-H146, NCI-H187, NCI-H510, and NCI-H209). NCI-N417 SCLC cells adopted a flattened morphology on laminin, and a classic SCLC cell line (NCI-H345) demonstrated a neuron-like appearance while the other SCLC cell lines except NCI-H187 cells, attached but did not spread. Adhesion to laminin was associated with increased resistance to several cytotoxic drugs. Matrigel, an extract of basement membrane proteins, greatly accelerated tumor growth when coinjected with SCLC cells in athymic mice. A synthetic peptide from the B1 chain of laminin, cyclic-YIGSR (Tyr-Ile-Gly-Ser-Arg), inhibited laminin-induced SCLC cell adhesion and migration in vitro and reduced the size of the tumors they formed when coinjected with matrigel and YIGSR. These results suggest that the interaction of SCLC cells with laminin and possibly with other basement membrane proteins can enhance their tumorigenicity and drug resistance.  相似文献   
99.
100.

Background

In trauma resuscitation with resuscitative endovascular balloon occlusion of the aorta (REBOA), urgent and accurate placement of the catheter in the resuscitation area without fluoroscopy can shorten the time from admission to REBOA, allowing rapid, temporary control of bleeding.

Discussion

The experience-based protocol in our center for ultrasound-guided REBOA in the resuscitation area without fluoroscopy is as follows: the femoral artery is punctured and a guidewire inserted; sonography is used to verify that the guidewire is in the abdominal aorta; the position of the balloon is confirmed with ultrasound after estimating the distance to the clavicle, and the pressure in the radial artery and sheath is used to monitor correct positioning; connect the pressure transducer to the catheter sheath for continuous monitoring of the blood pressure in the sheath, and inflate the balloon until the blood pressure tracing at the sheath has disappeared; check the pulse in the left radial artery, and withdraw the catheter slightly if the pulse in the radial artery is not palpable or is decreased (if this pulse is not palpable or decreased, the balloon is in the aortic arch). In this retrospective review of our REBOA protocol, between April 2012 and March 2016, 34 patients were enrolled. Two patients had complications, including dissection of the femoral artery in one and difficult percutaneous vascular access in another. Median time needed to complete the procedure was 8 min. Overall, 24 of 34 patients survived more than 24 h (72%), and overall mortality was 47%. Patients who lived more than 24 h, and then died had severe traumatic brain injury or septic shock.

Conclusions

Ultrasound-guided REBOA is presented. Monitoring the blood pressure in the left radial artery allows us to determine adequate positioning of the balloon, and the blood pressure in the catheter sheath located in the femoral artery should also be monitored to prevent aortic injuries caused by the overinflation of the balloon.  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