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   4234篇
  免费   211篇
  国内免费   28篇
耳鼻咽喉   20篇
儿科学   98篇
妇产科学   91篇
基础医学   575篇
口腔科学   48篇
临床医学   276篇
内科学   1021篇
皮肤病学   53篇
神经病学   461篇
特种医学   101篇
外科学   482篇
综合类   18篇
预防医学   257篇
眼科学   34篇
药学   286篇
中国医学   10篇
肿瘤学   642篇
  2024年   10篇
  2023年   30篇
  2022年   66篇
  2021年   106篇
  2020年   64篇
  2019年   69篇
  2018年   118篇
  2017年   86篇
  2016年   93篇
  2015年   120篇
  2014年   146篇
  2013年   196篇
  2012年   298篇
  2011年   284篇
  2010年   156篇
  2009年   171篇
  2008年   308篇
  2007年   282篇
  2006年   274篇
  2005年   241篇
  2004年   260篇
  2003年   200篇
  2002年   181篇
  2001年   73篇
  2000年   73篇
  1999年   71篇
  1998年   49篇
  1997年   48篇
  1996年   44篇
  1995年   30篇
  1994年   32篇
  1993年   31篇
  1992年   35篇
  1991年   28篇
  1990年   28篇
  1989年   24篇
  1988年   21篇
  1987年   20篇
  1986年   27篇
  1985年   14篇
  1984年   18篇
  1983年   11篇
  1982年   5篇
  1981年   3篇
  1980年   5篇
  1979年   8篇
  1978年   5篇
  1977年   3篇
  1976年   3篇
  1885年   1篇
排序方式: 共有4473条查询结果,搜索用时 15 毫秒
1.
Biliopancreatic diversion is a very effective method for weight reduction. In some instances it is too effective and needs to be revised.  相似文献   
2.
Forty consecutive adult patients under the age of 50 with acute non-lymphoblastic leukemia (ANLL) in first complete remission, underwent autologous bone marrow transplantation (ABMT) between March 1984 and April 1990. The conditioning regimen employed included cyclophosphamide and total body irradiation, followed by the administration of unpurged ABMT. The median time from diagnosis to transplant was 7 months (3-15 months), and the median time from complete remission to ABMT was 4 months (range 3-9 months). Twenty-two (51%) patients remain in complete remission 6-81 months (median 24 months) after ABMT.

The causes of death were, recurrent leukemia (11 patients), parenchymal toxicities such as acute respiratory distress syndrome and veno-occlusive disease (3 patients), hemorrhage (2 patients) and infection (2 patients). Eleven patients relapsed after 3-12 months (median 5 months). This study has produced survival data comparable to those of other institutions employing TBI for either allo or autotransplants.  相似文献   
3.
Summary 4-amino-1-hydroxybutylidene-1,1-bis-phosphonate (AHButBP) was given intravenously (2.5–25 mg/day for 4 days) to 14 patients with Paget's disease of bone, five of whom had been treated with dichloromethylidene bisphosphonate (Cl2MBP) 32 months earlier. In the nine patients who had not been treated previously with bisphosphonates, the short course of AHButBP induced a suppression of serum alkaline phosphatase and urinary hydroxyproline values down to 30% of initial values. The biochemical suppression of the disease was sustained for 2–18 months and the time to relapse did correlate to the logarithm of the dose (P<0.001). In the five patients previously treated for Paget's disease, an apparent resistence to treatment with AHButBP was observed. However, in these patients both serum alkaline phosphatase and urinary hydroxyproline fell to or even below the nadir values which had previously been achieved with Cl2MBP, irrespective of the degree of relapse. Thus the degree of suppression of Paget's disease of bone, achievable after treatment with bisphosphonates, seems to be constant for each patient, such that normal levels of serum alkaline phosphatase and urinary hydroxyproline cannot usually be attained in patients with extremely active disease.  相似文献   
4.
The aim of this work is to correlate the net kidney uptake of99mTc-aprotinin (TcA) in 103 subjects with separate effective renal plasma flow (ERPF) and some blood chemistry parameters at 90, 180, and 360 min postinjection both in the normal and diseased kidney. Correlations found with separate ERPFs are highly significant at any time (P < 0.001). However, although the slope of the regression line is steeper at 180 min,r tends to deteriorate slightly with time postinjection and a higher intercept on they axis: this pattern is more pronounced if diseased kidneys are considered separately. The following are probably related to the renal handling of TcA: (1) Early scans better reflect blood flow to the kidney, while later scans are more related to the metabolism/excretion tubular mechanisms; (2) correlations found with urea, creatinine, urea clearance, and creatinine clearance are highly significant at any time; (3) in 20 additional patients with diseased kidneys, renal uptake measurements done 360 min postinjection first with TcA and then with DMSA showed better correlations with ERPF employing TcA. Our results indicate that TcA is a feasible indicator of split renal function even at 90 min postinjection when a scan is easily carried out on an outpatient basis.This paper was in part presented at the European Nuclear Medicine Congress, August 14–17, 1984, Helsinki, Finland  相似文献   
5.
The temporal changes in childhood and adolescent cancer survival in Sweden 1960-1984 were analyzed. Complete follow-up through 1986 of 6,262 patients younger than 20 years at diagnosis revealed that the overall 5-year survival rates increased from 36.1 to 65.7% in males and from 43.6 to 73.6% in females. The temporal trends differed markedly between age groups and tumour sites and types. Over the study period, 5-years, survival for testicular cancer increased from 46.9 to 87.2%, kidney cancer, predominantly Wilms' tumour from 35.5 to 77.1% (with a higher rate of 89.1% in 1975-1979), Hodgkin's disease from 61.2 to 91.9%, non-Hodgkin's lymphoma from 32.5 to 76.6%, and all leukemias from 8.9 to 58.7%. Only a moderate improvement was noted for tumours of the bone, muscle and connective tissue, and survival rates for tumours of the nervous system remained largely unchanged. Our data reflect the remarkable therapeutic improvements that have occurred for cancer in the young and indicate that these improvements have rapidly become available in Sweden.  相似文献   
6.
A number of designations--for example excision, wide excision, lumpectomy, tylectomy, extended tylectomy, partial mastectomy, tumorectomy, segmental resection and quadrantectomy--have been applied to operative procedures aimed at treating mammary carcinoma with preservation of the breast. None of them, however, has been explicitly linked to a defined surgical technique and there is no consensus about the terminology. We propose a simple classification system for breast-conserving procedures, which can facilitate the communication between surgeons and the interpretation and exchange of scientific data. We also describe a strictly defined and locally radical partial mastectomy--a sector resection--which has been used at several centres in Sweden for more than 5 years with a favourable outcome so far in terms of local tumour control and the cosmetic result.  相似文献   
7.
Water suppressed proton nuclear magnetic resonance (1H NMR) spectroscopy of human plasma has been described as successful in detection of malignancy. We designed a prospective study to test the hypothesis that in vitro NMR spectroscopy has a high sensitivity for detecting early breast cancer. One hundred and thirty-five women were referred for breast biopsy due to abnormal mammograms. One hundred of these were recruited through a population-based mammography screening project. Sixty-nine of 135 women were found to have breast cancer and their average line width of the methyl and methylene resonance in the plasma were compared to those women who had a benign or normal histopathology in the biopsy and to the line width for 100 healthy subjects from the same population. The mean line width at a half-height of the methyl and methylene resonances of the serum lipoprotein lipids in the NMR spectrum did not differ appreciably between the groups. The line width correlated highly with the serum triglycerides, but correction for the level of triglycerides did not improve the diagnostic accuracy of the line width. Receiver-operating characteristic analysis revealed a sensitivity of 61% and a false positive rate of 43% at the most beneficial cut-off of line width (39.7 Hz). In vitro NMR spectroscopy in our hands was thus not a useful diagnostic tool in patients with early breast cancer.  相似文献   
8.
Recent years have witnessed increased antipsychotic treatment of children despite limited long‐term safety data in children. In this study, motor side effects associated with the use of antipsychotic drugs in children were examined in a sample of pediatric psychiatric patients. Child and adolescent psychiatric patients receiving antipsychotics (most were on atypicals) for 6 months or longer (n = 118) were compared with antipsychotic‐naïve patients (n = 80) with similar age, sex ratio, and diagnoses. Only 19% of patients on antipsychotics had ever experienced psychotic symptoms. Eleven children (9%) on antipsychotics exhibited dyskinesia, when compared with 0 in the naïve group (P = 0.003, Fisher's exact test). Nine of 62 African–American children (15%) on antipsychotics exhibited dyskinesia, when compared with only 4% (2 of 52) of European–American children (P = 0.003, Fisher's exact test). Children treated with antipsychotic drugs might experience a significant risk of dyskinesia even when treated only with atypical antipsychotics. Ethnicity might also be a risk factor for dyskinesia in children. Side‐effect profile of the atypical antipsychotic drugs in children may be much different than that in adults. © 2007 Movement Disorder Society  相似文献   
9.
The aim of this study was to image the extra domain B (ED-B) of fibronectin, an angiogenesis-related target, in solid tumors using small-animal PET. Toward this aim, an ED-B fibronectin-binding human antibody derivative (L19-SIP) was labeled with (76)Br via an enzymatic approach. Biodistribution and imaging studies were performed in human teratoma-bearing mice for up to 48 h after injection. METHODS: L19-SIP was labeled with (76)Br using bromoperoxidase/H(2)O(2). The stability of the labeled antibody was tested both in vitro and in vivo. Biodistribution and small-animal imaging studies (PET and CT) were performed in F9-bearing 129/sv mice (n = 3 or 4). RESULTS: The enzymatic radiobromination approach afforded the labeled antibody in high yield (>55%) under mild reaction conditions. (76)Br-L19-SIP stability in mouse serum proved to be similar to that of the (125)I-labeled analog (>80% of intact material at 48 h after injection). Fast and specific in vivo targeting was obtained in tumors and other organs expressing ED-B fibronectin (i.e., ovaries and uterus). However, slow renal clearance and persistent activity predominately in blood and stomach suggests partial (76)Br-L19-SIP debromination in vivo. This debromination was confirmed in a metabolism study in normal mice. The F9 tumors were clearly imaged by small-animal PET at each considered time point, starting at 5 h up to 48 h after injection. CONCLUSION: (76)Br-L19-SIP specifically accumulated at the target site, enabling detailed small-animal PET of tumor neovasculature. Therefore, targeting the angiogenesis-associated expression of ED-B fibronectin can be a valuable tool for tumor detection using molecular imaging with PET.  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