全文获取类型
收费全文 | 1428篇 |
免费 | 79篇 |
国内免费 | 17篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 56篇 |
妇产科学 | 21篇 |
基础医学 | 142篇 |
口腔科学 | 40篇 |
临床医学 | 118篇 |
内科学 | 292篇 |
皮肤病学 | 21篇 |
神经病学 | 35篇 |
特种医学 | 250篇 |
外科学 | 114篇 |
综合类 | 36篇 |
预防医学 | 42篇 |
眼科学 | 5篇 |
药学 | 128篇 |
中国医学 | 2篇 |
肿瘤学 | 215篇 |
出版年
2023年 | 5篇 |
2022年 | 8篇 |
2021年 | 28篇 |
2020年 | 18篇 |
2019年 | 11篇 |
2018年 | 17篇 |
2017年 | 19篇 |
2016年 | 18篇 |
2015年 | 26篇 |
2014年 | 27篇 |
2013年 | 37篇 |
2012年 | 38篇 |
2011年 | 40篇 |
2010年 | 46篇 |
2009年 | 47篇 |
2008年 | 46篇 |
2007年 | 39篇 |
2006年 | 47篇 |
2005年 | 42篇 |
2004年 | 36篇 |
2003年 | 54篇 |
2002年 | 46篇 |
2001年 | 28篇 |
2000年 | 39篇 |
1999年 | 43篇 |
1998年 | 57篇 |
1997年 | 63篇 |
1996年 | 50篇 |
1995年 | 32篇 |
1994年 | 44篇 |
1993年 | 33篇 |
1992年 | 23篇 |
1991年 | 27篇 |
1990年 | 21篇 |
1989年 | 43篇 |
1988年 | 32篇 |
1987年 | 35篇 |
1986年 | 38篇 |
1985年 | 30篇 |
1984年 | 31篇 |
1983年 | 19篇 |
1982年 | 16篇 |
1981年 | 29篇 |
1980年 | 12篇 |
1979年 | 8篇 |
1978年 | 17篇 |
1977年 | 12篇 |
1976年 | 12篇 |
1975年 | 11篇 |
1967年 | 5篇 |
排序方式: 共有1524条查询结果,搜索用时 15 毫秒
71.
NiX HouY KingBR TangX ReadMA SmithR NicholsonRC 《第二军医大学学报》2005,26(4):385-385
Placental CRH plays a major role in the mechanisms controlling human pregnancy and parturition. Understanding how placental CRH production is regulated is therefore of importance. Previously we have shown that placental expression of CRH peptide and mRNA are inhibited by estrogens, in contrast to the stimulatory effects of estrogen on hypothalamic CRH production. Our current study found that in placental cells cotransfected with a CRH promoter construct and an estrogen receptor-alpha expression vector results in a differential regulation whereby 17beta estradiol (E2) decreased and the putative pure estrogen antagonist, ICI 182780, 相似文献
72.
A J M Ferreri M Ponzoni G P Dognini M-Q Du C Doglioni J Radford R Dolcetti F Cavalli 《Annals of oncology》2006,17(11):1721-1722
We read with great interest the article by Grünberger etal. on the blind administration of doxycyclinein a retrospective series of 11 patients with ocular adnexallymphoma of MALT-type (OAL) [1]. Authors used this therapy onthe basis that, in the Italian experience [2], most cases ofOAL were shown to be related to chlamydial 相似文献
73.
Rosemary RC McEachan Rebecca J Lawton Cath Jackson Mark Conner Jennifer Lunt 《BMC public health》2008,8(1):326
Background
The workplace is an ideal setting for health promotion. Helping employees to be more physically active can not only improve their physical and mental health, but can also have economic benefits such as reduced sickness absence. The current paper describes the development of a three month theory-based intervention that aims to increase levels of moderate intensity physical activity amongst employees in sedentary occupations. 相似文献74.
Buser K. S.; Joss R. A.; Piquet D.; Aapro M. S.; Cavalli F.; Haefliger J. M.; Jungi W. F.; Bauer J.; Obrist R.; Brunner K. W.; Weber T.; Verity L.; Butcher M. 《Annals of oncology》1993,4(6):475-479
BACKGROUND:: The combination of cyclophosphamide, methotrexate and 5-fluorouracil(CMF) is a widely used chemotherapy regimen in breast cancerpatients. However, the control of nausea and vomiting inducedby oral CMF is a rarely examined problem. Therefore we felta randomized, placebo controlled study justified in order toimprove currently available antiemetic therapy. SUBJECTS AND METHODS:: In a randomised double-blind trial ondansetron given orally,8 mg three times a day for 15 days, was compared with placeboin 82 breast cancer patients receiving chemotherapy with CMF(cyclophosphamide 100 mg/m2 orally days 114, methotrexate40 mg/m2 i.v. days 1 and 8 and 5-fluorourcil 600 mg/m2 i.v.days 1 and 8). The patients recorded nausea and the number ofvomits and retches daily on diary cards. Forty-two patientsreceived ondansetron and 40 received placebo. RESULTS:: Significantly more patients who received ondansetron experiencedneither vomiting nor retching (emesis) compared to those receivingplacebo over a 15 day treatment period (60% vs. 35%, p = 0.027).The difference, with 95% confidence limits, was estimated as25 (4.45%). Furthermore, there was a trend in favour of ondansetronin the control of nausea. Ondansetron was well tolerated, with25 patients (59%) reporting at least 1 adverse event comparedto 18 patients (45%) receiving placebo (p = 0.191). CONCLUSION:: The results indicate that ondansetron given orally for 15 daysis safe and effective in the control of emesis induced by CMF.It is however too early to recommend ondansetron as standardantiemetic therapy for oral CMF, as the treatment of nauseaand vomiting in this setting has not been studied thoroughlyenough. prospective, randomized, double-blind trial, ondansetron and placebo, oral CMF-regimen, breast cancer 相似文献
75.
Recently, the beneficial role of steroids for acute laryngotracheobronchitis has been more clearly defined for both intubated and unintubated patients. However, corticosteroids also improve the clinical signs of airway haemangiomata. Two patients are described who illustrate how this can be a source of diagnostic confusion. 相似文献
76.
Population genetics of phenylketonuria 总被引:1,自引:0,他引:1
Phenylketonuria (PKU) is an autosomal recessive disorder caused by a large number of mutations at the phenylalanine hydroxylase (PAH) locus, most of which are strongly associated with specific RFLP or VNTR haplotypes. One of the major questions remaining in PKU research is why this apparently maladaptive disorder has been maintained at a frequency of approximately 1 in 10000 among Caucasians. A growing number of studies have provided evidence that both the relatively high frequency of PKU and the strong mutation/haplotype associations might reflect the existence of multiple founding populations for PKU. Examples of putative founding populations for PKU in both Europe and Asia will be presented. Some PAH mutations are associated with multiple haplotypes, suggesting recurrence. Evidence for and against recurrence as the mechanism responsible for the association of the R408W mutation with RFLP haplotypes 1 and 2 will be discussed. 相似文献
77.
Molecular analysis of PKU in Ireland 总被引:1,自引:0,他引:1
CA O'Neill RC Eisensmith DT Croke ER Naughten SF Cahalane SLC Woo 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S407):43-44
Classical phenylketonuria (PKU: McKusick No. 261600) is caused by mutations occurring at the phenylalanine hydroxylase (PAH) locus on chromosome 12 and has a prevalence in Ireland of 1 in 4500. We examined 304 independent alleles from 350 patients for the presence of six mutations and have characterized VNTR alleles within the minisatellite region 3' to the PAH gene in patients carrying the most prevalent mutation. R408W was the most common mutation found, with a relative frequency of 42%. All other mutations had relative frequencies of <10%. VNTR analysis showed that the R408W mutation is associated with the VNTR-8 allele in the Irish population, indicating that R408W is associated with RFLP haplotype 1. This differs from that reported from eastern Europe where R408W is associated with RFLP haplotype 2/VNTR-3; an observation which has led several groups to propose a Balto-Slavic origin for this mutation. These results support the hypothesis of a second, independent founding event for the R408W mutation on an RFLP haplotype 1 VNTR-8 chromsome background in the Irish/Celtic population. 相似文献
78.
OBJECTIVE--To determine the prevalence of behaviour disorders in low birthweight infants. DESIGN--Children of birth weight < or = 2000 g born to mothers resident in Merseyside in 1980-1 assessed using the Rutter parent and teacher behaviour questionnaires and the Conner modification of the Rutter teacher questionnaire. Children attending normal schools were assessed with controls matched for age, sex, and class in school. Children attending special schools were assessed unmatched. SUBJECTS--233 matched case-control pairs attending normal primary schools and 46 unmatched children attending special schools. SETTING--Primary and special schools. MAIN OUTCOME MEASURES--Emotional, conduct, and undifferentiated behaviour disorders and hyperactivity. RESULTS--On the parental questionnaire screen, 36% of the cases and 22% of the controls had a behaviour disorder and on the teacher questionnaire the proportions were 27% and 12% respectively. Hyperactivity was significantly more common among male cases than their controls (21% v 5.0%) but differed little among female cases and controls (9% v 7%). CONCLUSIONS--Improving neonatal survival of low birthweight infants is accompanied by a higher prevalence of behaviour disorders. The long term implications for psychiatric morbidity and other adult disease must be monitored. 相似文献
79.
Cellular uptake and cytotoxicity of solid lipid nanospheres (SLN) incorporating doxorubicin or paclitaxel 总被引:2,自引:0,他引:2
Miglietta A Cavalli R Bocca C Gabriel L Gasco MR 《International journal of pharmaceutics》2000,210(1-2):61-67
Solid Lipid Nanospheres (SLN) are colloidal therapeutic systems proposed for several administration routes and obtained by dispersing warm microemulsions in cold water. SLN as carriers of doxorubicin and paclitaxel have been previously studied. In this study, the cellular uptake of SLN and the cytotoxicity of doxorubicin and paclitaxel incorporated into SLN were investigated on two cell-lines, human promyelocytic leukemia (HL60) and human breast carcinoma (MCF-7). Cellular uptake of SLN was determined by incorporating 6-coumarin as fluorescent marker. The cellular uptake of fluorescent SLN was clearly evidenced by fluorescence microscopy. The cytotoxicity of doxorubicin incorporated in SLN was higher compared to the conventional doxorubicin solution, even at the lower concentrations. Paclitaxel in SLN was about 100-fold more effective than free paclitaxel on MCF-7 cells, while on HL60 cells a lower sensitivity was achieved with paclitaxel in SLN. Unloaded SLN had no cytotoxic effect on HL60 and MCF-7 cells. 相似文献
80.
Bertoni F Müllenbach R Broggini M Roggero E Cavalli F Cotter FE Zucca E 《Leukemia & lymphoma》2000,38(5-6):605-610
DNA amplification by polymerase chain reaction (PCR) with primers designed on the widely distributed Alu sequences allows the production of specific inter-Alu DNA-fingerprints. Amplification of tumour and matched normal DNA can show differences due to genetic alterations within the tumour genome. We applied this approach to study low-grade extranodal marginal zone B-cell lymphoma (of MALT type). After digestion with restriction enzymes, DNA samples were separately amplified by PCR with three different Alu-primers. A comparison between the fingerprint pattern from lymphoma and normal samples was made. Inter-Alu bands differing between the two samples were excised from the gel, cloned and sequenced. Nine cases of low-grade MALT-lymphomas have been analysed, giving seventeen different bands between tumour and normal. DNA sequence analysis showed identities for three of them with sequences available at the GenBank. The methodology of Alu-PCR to detect DNA-based abnormalities, in addition or combination with RNA-based methods, is a powerful tool to identify candidate regions frequently altered in tumours. With the increased available genomic sequences through the Human Genome Project, there will be an increasing probability of picking up perfect homologies with these sequences using cloned differential Alu-PCR bands in BLAST searches through genome databases. 相似文献