全文获取类型
收费全文 | 1924篇 |
免费 | 257篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 23篇 |
儿科学 | 43篇 |
妇产科学 | 43篇 |
基础医学 | 307篇 |
口腔科学 | 19篇 |
临床医学 | 177篇 |
内科学 | 487篇 |
皮肤病学 | 32篇 |
神经病学 | 120篇 |
特种医学 | 80篇 |
外科学 | 177篇 |
综合类 | 39篇 |
预防医学 | 350篇 |
眼科学 | 50篇 |
药学 | 159篇 |
中国医学 | 2篇 |
肿瘤学 | 76篇 |
出版年
2021年 | 23篇 |
2019年 | 15篇 |
2018年 | 22篇 |
2016年 | 18篇 |
2015年 | 23篇 |
2014年 | 36篇 |
2013年 | 51篇 |
2012年 | 91篇 |
2011年 | 82篇 |
2010年 | 44篇 |
2009年 | 57篇 |
2008年 | 72篇 |
2007年 | 105篇 |
2006年 | 111篇 |
2005年 | 117篇 |
2004年 | 106篇 |
2003年 | 89篇 |
2002年 | 72篇 |
2001年 | 67篇 |
2000年 | 53篇 |
1999年 | 69篇 |
1998年 | 32篇 |
1997年 | 33篇 |
1996年 | 30篇 |
1995年 | 27篇 |
1994年 | 20篇 |
1993年 | 25篇 |
1992年 | 49篇 |
1991年 | 31篇 |
1990年 | 28篇 |
1989年 | 29篇 |
1988年 | 35篇 |
1987年 | 35篇 |
1986年 | 34篇 |
1985年 | 32篇 |
1984年 | 18篇 |
1983年 | 26篇 |
1982年 | 14篇 |
1981年 | 24篇 |
1980年 | 19篇 |
1979年 | 32篇 |
1978年 | 18篇 |
1977年 | 19篇 |
1976年 | 24篇 |
1975年 | 19篇 |
1974年 | 23篇 |
1973年 | 20篇 |
1972年 | 15篇 |
1971年 | 19篇 |
1968年 | 15篇 |
排序方式: 共有2184条查询结果,搜索用时 15 毫秒
81.
Rachel N Manongi Fortunata R Nasuwa Rose Mwangi Hugh Reyburn Anja Poulsen Clare IR Chandler 《Human resources for health》2009,7(1):50
Background
Patient, or parent/guardian, satisfaction with health care provision is important to health outcomes. Poor relationships with health workers, particularly with nursing staff, have been reported to reduce satisfaction with care in Africa. Participatory research approaches such as the Health Workers for Change initiative have been successful in improving provider-client relationships in various developing country settings, but have not yet been reported in the complex environment of hospital wards. We evaluated the HWC approach for improving the relationship between nurses and parents on a paediatric ward in a busy regional hospital in Tanzania. 相似文献82.
Hans Sanderson Brian Laird Richard Brain Christian J. Wilson Keith R. Solomon 《Ecotoxicology (London, England)》2009,18(7):838-845
Zooplankton abundance and species richness in 15 untreated 12,000 L outdoor microcosms (n = 15) were monitored over the course of 1 year to document the inherent variability and statistical detectability between replicates. Statistical power analysis were applied to derive the statistically minimal detectable difference (MDD) between replicates with default values set at; α = 0.1 and β = 0.2. Copepod abundance and species richness generally demonstrated the best detectability at 0.31 and 0.16, respectively, (n = 15); 0.59 and 0.33 (n = 3). Total zooplankton abundance and species richness had the lowest detectabilities at 0.19 and 0.14, respectively, (n = 15); 0.35 and 0.3 (n = 3). Rotifers, due to their opportunistic and rapid life traits, had the lowest single-species abundance detectabilities at 0.54 (n = 15); 0.8 (n = 3), whereas macroinvertebrate species richness had the lowest detectability at 0.43 (n = 15); 0.7 (n = 3) over 1 year. We recommend a priori calibration of the study design relative to relevant MDDs. Moreover, it is suggested to consider alternatives to statistical null hypothesis testing. 相似文献
83.
D P Maudgal D Lawrence F M Sanderson T C Northfield 《British journal of clinical pharmacology》1979,8(3):229-232
1 Pancreatic and biliary function were studied in eight patients taking oral cimetidine (1.6 g/day for 6 weeks) for endoscopically confirmed active peptic ulcer disease. 2 Postprandial jejunal tryptic activity and bile acid concentration were unchanged during cimetidine given for 1 and 6 weeks. 3 Postprandial gallbladder emptying was also unchanged. 4 Direct examination of postprandial upper jejunal aspirate for deconjugated bile acids was negative in all patients; but the more sensitive [14C]-glycocholate bile acid breath test showed a significant increase in breath 14CO2, indicating increased bacterial deconjugation of bile acids in the gastrointestinal tract. 相似文献
84.
85.
86.
87.
88.
89.
Nonrandom cytogenetic alterations in hepatocellular carcinoma from transgenic mice overexpressing c-Myc and transforming growth factor-alpha in the liver 下载免费PDF全文
Sargent LM Zhou X Keck CL Sanderson ND Zimonjic DB Popescu NC Thorgeirsson SS 《The American journal of pathology》1999,154(4):1047-1055
Identification of specific and primary chromosomal alterations during the course of neoplastic development is an essential part of defining the genetic basis of cancer. We have developed a transgenic mouse model for liver neoplasia in which chromosomal lesions associated with both the initial stages of the neoplastic process and the acquisition of malignancy can be analyzed. Here we analyze chromosomal alterations in 11 hepatocellular carcinomas from the c-myc/TGF-alpha double-transgenic mice by fluorescent in situ hybridization with whole chromosome probes, single-copy genes, and 4'-6-diamidino-2-phenylindole (DAPI-) and G-banded chromosomes and report nonrandom cytogenetic alterations associated with the tumor development. All tumors were aneuploid and exhibited nonrandom structural and numerical alterations. A balanced translocation t(5:6)(G1;F2) was identified by two-color fluorescent in situ hybridization in all tumors, and, using a genomic probe, the c-myc transgene was localized near the breakpoint on derivative chromosome der 6. Partial or complete loss of chromosome 4 was observed in all tumors with nonrandom breakage in band C2. Deletions of chromosome 1 were observed in 80% of the tumors, with the most frequent deletion at the border of bands C4 and C5. An entire copy of chromosome 7 was lost in 80% of the tumors cells. Eighty-five percent of the tumor cells had lost one copy of chromosome 12, and the most common breakpoint on chromosome 12 occurred at band D3 (28%). A copy of chromosome 14 was lost in 72%, and band 14E1 was deleted in 32% of the tumor cells. The X chromosome was lost in the majority of the tumor cells. The most frequent deletion on the X chromosome involved band F1. We have previously shown that breakages of chromosomes 1, 6, 7, and 12 were observed before the appearance of morphologically distinct neoplastic liver lesions in this transgenic mouse model. Thus breakpoints on chromosome 4, 9, 14, and X appear to be later events in this model of liver neoplasia. This is the first study to demonstrate that specific sites of chromosomal breakage observed during a period of chromosomal instability in early stages of carcinogenesis are later involved in stable rearrangements in solid tumors. The identification of the 5;6 translocation in all of the tumors has a special significance, being the first balanced translocation reported in human and mouse hepatocellular carcinoma and having the breakpoint near a tumor susceptibility gene and myc transgene site of integration. Moreover, its early occurrence indicates that this is a primary and relevant alteration to the initiation of the neoplastic process. In addition, the concordance between the breakpoints observed during the early dysplastic stage of hepatocarcinogenesis and the stable deletions of chromosomes 1, 4, 6, 7, 9, and 12 in the tumors provides evidence for preferential site of genetic changes in hepatocarcinogenesis. 相似文献
90.