全文获取类型
收费全文 | 755篇 |
免费 | 75篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 54篇 |
妇产科学 | 18篇 |
基础医学 | 140篇 |
口腔科学 | 5篇 |
临床医学 | 83篇 |
内科学 | 105篇 |
皮肤病学 | 19篇 |
神经病学 | 63篇 |
特种医学 | 14篇 |
外科学 | 73篇 |
综合类 | 3篇 |
预防医学 | 60篇 |
眼科学 | 10篇 |
药学 | 51篇 |
肿瘤学 | 130篇 |
出版年
2024年 | 4篇 |
2023年 | 10篇 |
2022年 | 12篇 |
2021年 | 10篇 |
2020年 | 22篇 |
2019年 | 25篇 |
2018年 | 24篇 |
2017年 | 17篇 |
2016年 | 18篇 |
2015年 | 23篇 |
2014年 | 36篇 |
2013年 | 46篇 |
2012年 | 55篇 |
2011年 | 55篇 |
2010年 | 34篇 |
2009年 | 36篇 |
2008年 | 42篇 |
2007年 | 40篇 |
2006年 | 43篇 |
2005年 | 36篇 |
2004年 | 35篇 |
2003年 | 14篇 |
2002年 | 37篇 |
2001年 | 14篇 |
2000年 | 10篇 |
1999年 | 14篇 |
1998年 | 14篇 |
1997年 | 6篇 |
1996年 | 7篇 |
1995年 | 8篇 |
1994年 | 4篇 |
1993年 | 6篇 |
1992年 | 4篇 |
1991年 | 10篇 |
1990年 | 7篇 |
1989年 | 5篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1986年 | 8篇 |
1985年 | 4篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1982年 | 6篇 |
1981年 | 5篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 3篇 |
1977年 | 1篇 |
1976年 | 5篇 |
1973年 | 2篇 |
排序方式: 共有831条查询结果,搜索用时 15 毫秒
71.
The aim of this study was to obtain an understanding of what it means to be a hospice volunteer in a country without a tradition of hospice or palliative volunteer care services. Ten volunteers from three different hospices in Sweden were interviewed. Their narratives were interpreted with a phenomenological hermeneutic method. Three themes were disclosed: motives for becoming involved in hospices, encountering the hospice and encountering the patient. The interpretations disclose a need for the volunteer to be affirmed as a caring person and received in fellowship at the hospice. Positive encounters with a hospice are closely related to personal growth. Volunteers feel rejected if their need for meaning and for belonging to the hospice is not satisfied. This shows that hospices need to set goals in terms of volunteer support, particularly regarding existential issues following the encounter with the hospice and the patient. 相似文献
72.
Joakim Olbers Ellen Jacobson Fredrik Viberg Nils Witt Petter Ljungman Mrten Rosenqvist Jan
stergren 《Journal of clinical hypertension (Greenwich, Conn.)》2019,21(3):363-368
Direct current (DC) cardioversion is used to convert persistent atrial fibrillation (AF) to sinus rhythm (SR), but there is limited knowledge about how blood pressure (BP) is affected by conversion to SR. We sought to evaluate how BP changed in AF patients who converted to SR, compared to patients still in AF. In this retrospective registry analysis, we included a total of 487 patients, treated with DC cardioversion for persistent AF. We obtained data regarding medical history, medication, BP, and electrocardiogram the day before and 7 days after cardioversion. Systolic BP increased by 9 (±16) mm Hg (P < 0.01) and diastolic BP decreased by 3 (±9) mm Hg (P < 0.01) after conversion to SR. In the group of patients with restored SR, there was a 40% increase in the proportion of patients with a hypertensive BP level (≥140/90 mm Hg) after DC cardioversion compared to before. Patients still in AF had no significant change in BP. Systolic BP increases and diastolic BP slightly decreases when persistent AF is converted to SR. The underlying mechanisms explaining these findings are not known, but may involve either hemodynamic changes that occur when SR is restored, an underestimation of systolic BP in AF, or a combination of both. Our findings suggest that an increased attention to BP levels after a successful cardioversion is warranted. 相似文献
73.
Schauber J Bark T Jaramillo E Katouli M Sandstedt B Svenberg T 《Scandinavian journal of gastroenterology》2000,35(2):184-189
BACKGROUND: Rectal instillation of short-chain fatty acids (SCFA), important nutrients for the colorectal mucosa, has been suggested to be of therapeutic value in distal intestinal inflammation. METHODS: In this study nine patients with Hartmann-closed rectum after colectomy for acute colitis were investigated. In a double-blind crossover trial an enema containing SCFA or a placebo solution was administered twice daily for 3 weeks. Before entry into the protocol, after each treatment period, and 6 weeks after the study period the patients' symptoms were evaluated, rectal endoscopy was performed, histologic samples were scored, and microbiologic analyses were carried out. RESULTS: No significant differences in symptoms, in mucosal inflammation, in histologic scoring, or in microbiologic studies were found between SCFA and placebo periods. Unexpectedly, all but one patient entirely lacked coliform bacteria in the rectum. CONCLUSIONS: In this study SCFA enemas had no beneficial effect on inflammation in excluded rectum in patients earlier submitted to colectomy for colitis. However, a different rectal flora was detected in these patients. 相似文献
74.
Alfredsson J Stenestrand U Wallentin L Swahn E 《Heart (British Cardiac Society)》2007,93(11):1357-1362
Objective
To study gender differences in management and outcome in patients with non‐ST‐elevation acute coronary syndrome.Design, setting and patients
Cohort study of 53 781 consecutive patients (37% women) from the Register of Information and Knowledge about Swedish Heart Intensive care Admissions (RIKS‐HIA), with a diagnosis of either unstable angina pectoris or non‐ST‐elevation myocardial infarction. All patients were admitted to intensive coronary care units in Sweden, between 1998 and 2002, and followed for 1 year.Main outcome measures
Treatment intensity and in‐hospital, 30‐day and 1‐year mortality.Results
Women were older (73 vs 69 years, p<0.001) and more likely to have a history of hypertension and diabetes, but less likely to have a history of myocardial infarction or revascularisation. After adjustment, there were no major differences in acute pharmacological treatment or prophylactic medication at discharge.Revascularisation was, however, even after adjustment, performed more often in men (OR 1.15; 95% CI, 1.09 to 1.21). After adjustment, there was no significant difference in in‐hospital (OR 1.03; 95% CI, 0.94 to 1.13) or 30‐days (OR 1.07; 95% CI, 0.99 to 1.15) mortality, but at 1 year being male was associated with higher mortality (OR 1.12; 95% CI, 1.06 to 1.19).Conclusion
Although women are somewhat less intensively treated, especially regarding invasive procedures, after adjustment for differences in background characteristics, they have better long‐term outcomes than men.Since the beginning of the 1990s there have been numerous studies on gender differences in management of acute coronary syndromes (ACS). Many earlier studies,1,2,3,4,5,6,7,8 but not all,9 found that women were treated less intensively in the acute phase. In some of the studies, after adjustment for age, comorbidity and severity of the disease, most of the differences disappeared.6,7 There is also conflicting evidence on gender differences in evidence‐based treatment at discharge.1,3,5,6,8,10,11After acute myocardial infarction (AMI), a higher short‐term mortality in women is documented in several studies.2,5,6,7,12,13,14 After adjustment for age and comorbidity some difference has usually,2,5,12,13 but not always,11,14 remained. On the other hand, most studies assessing long‐term outcome have found no difference between the genders, or a better outcome in women, at least after adjustment.7,10,13,14 Earlier studies focusing on gender differences in outcome after an acute coronary syndrome have usually studied patients with AMI, including both ST‐elevation myocardial infarction and non‐ST‐elevation myocardial infarction (NSTEMI).2,5,6,7,12,13,14 However, the pathophysiology and initial management differs between these two conditions,15 as does outcome according to gender.11,16 In patients with NSTEMI or unstable angina pectoris (UAP), women seem to have an equal or better outcome, after adjustment for age and comorbidity.1,4,8,11,16,17 Studies on differences between genders, in treatment and outcome, in real life, contemporary, non‐ST‐elevation acute coronary syndrome (NSTE ACS) populations, large enough to make necessary adjustments for confounders, are lacking.The aim of this study was to assess gender differences in background characteristics, management and outcome in a real‐life intensive coronary care unit (ICCU) population, with NSTE ACS. 相似文献75.
Lisa Klasson Joakim Westberg Panagiotis Sapountzis Kristina Nslund Ylva Lutnaes Alistair C. Darby Zoe Veneti Lanming Chen Henk R. Braig Roger Garrett Kostas Bourtzis Siv G. E. Andersson 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(14):5725-5730
The obligate intracellular bacterium Wolbachia pipientis infects around 20% of all insect species. It is maternally inherited and induces reproductive alterations of insect populations by male killing, feminization, parthenogenesis, or cytoplasmic incompatibility. Here, we present the 1,445,873-bp genome of W. pipientis strain wRi that induces very strong cytoplasmic incompatibility in its natural host Drosophila simulans. A comparison with the previously sequenced genome of W. pipientis strain wMel from Drosophila melanogaster identified 35 breakpoints associated with mobile elements and repeated sequences that are stable in Drosophila lines transinfected with wRi. Additionally, 450 genes with orthologs in wRi and wMel were sequenced from the W. pipientis strain wUni, responsible for the induction of parthenogenesis in the parasitoid wasp Muscidifurax uniraptor. The comparison of these A-group Wolbachia strains uncovered the most highly recombining intracellular bacterial genomes known to date. This was manifested in a 500-fold variation in sequence divergences at synonymous sites, with different genes and gene segments supporting different strain relationships. The substitution-frequency profile resembled that of Neisseria meningitidis, which is characterized by rampant intraspecies recombination, rather than that of Rickettsia, where genes mostly diverge by nucleotide substitutions. The data further revealed diversification of ankyrin repeat genes by short tandem duplications and provided examples of horizontal gene transfer across A- and B-group strains that infect D. simulans. These results suggest that the transmission dynamics of Wolbachia and the opportunity for coinfections have created a freely recombining intracellular bacterial community with mosaic genomes. 相似文献
76.
Koskinen WJ Brøndbo K Mellin Dahlstrand H Luostarinen T Hakulinen T Leivo I Molijn A Quint WG Røysland T Munck-Wikland E Mäkitie AA Pyykkö I Dillner J Vaheri A Aaltonen LM 《Journal of cancer research and clinical oncology》2007,133(9):673-678
Purpose Human papillomavirus (HPV) has been linked to oropharyngeal carcinomas, but its role in laryngeal squamous cell carcinoma
(LSCC) is not clear. A prospective multicenter study based on known tumor-cell percentage of fresh frozen carcinoma biopsies
was established to determine the HPV prevalence. Moreover risk factors such as smoking, alcohol abuse, chronic laryngitis
and gastroesophageal reflux disease (GERD) were evaluated
Methods Fresh-frozen laryngeal cancer biopsies from 108 patients in Finland, Norway, and Sweden were investigated. Patients whose
biopsy samples contained at least 20% tumor tissue (N = 69) entered the study. HPV DNA was determined with MY09/11 and GP5+/6+ nested PCR and SPF10 PCR hybridization assay. Patients
were examined by an ENT specialist and an extensive questionnaire concerning risk factors was filled in.
Results Only three patients (4.4%) harbored HPV DNA in their carcinoma sample. Heavy alcohol drinking was associated with an increased
risk of death, advanced-stage disease, and younger age at diagnosis. Chronic laryngitis, GERD, and orogenital sex contacts
were rare. Poor oral hygiene was not associated with survival, although it correlated with heavy drinking.
Conclusion In our series HPV was not important in LSCC. Heavy drinking led to major mortality in LSCC and promoted early carcinogenesis.
This work was supported by grants from Cancer Societies of Finland, Helsinki University Hospital Research Funds, Finnish Dental
Society Apollonia, Stockholm Cancer Society and Laryngfonden, Sweden. 相似文献
77.
The role of B-cells in experimental myasthenia gravis in mice. 总被引:1,自引:0,他引:1
H B Wang H Li B He M Bakheit M Levi B Wahren A Bergl?f K Sandstedt H Link F D Shi 《Biomedicine & Pharmacotherapy》1999,53(5-6):227-233
Myasthenia gravis (MG) and experimental autoimmune myasthenia gravis (EAMG) are caused by auto-antibodies against the nicotinic acetylcholine receptor (AChR) at the postsynaptic membrane. To evaluate the extent to which the humoral immune response against AChR operates in the pathogenesis of EAMG, we immunized B-cell knockout (microMT) and wild type C57BL/6 mice with AChR in complete Freund's adjuvant. The ability of AChR-primed lymph node cells to proliferate and secrete IFN-gamma in response to AChR and its dominant peptide alpha 146-162 were intact in microMT as in wild type mice. Similar levels of mRNA for IFN-gamma, IL-4 and IL-10 in AChR-reactive lymph node cells were detected in microMT and wild type mice. However, microMT mice had no detectable anti-AChR antibodies and never developed clinical EAMG. We conclude that B-cells are critically required for the genesis of clinical EAMG, but not for AChR-specific T-cell priming. 相似文献
78.
79.
80.
Richard Torstenson Per Hartvig Bengt Lngstrm Gran Westerberg Joakim Tedroff 《Annals of neurology》1997,41(3):334-340
The effect of levodopa on L-[11C]DOPA influx rate was evaluated in patients with early and advanced Parkinson's disease (PD) by using positron emission tomography (PET). The patients were scanned both drug-free and after a subsequent therapeutic levodopa infusion. Regional analysis of striatal L-[11C]DOPA influx rate showed a correlation to the degenerative loss of nerve terminals reported at postmortem analysis in PD. Levodopa induced markedly differential effects on the striatal L-[11C]DOPA influx rate in early and advanced patients. In patients with mild PD, levodopa infusion decreased L-[11C]DOPA influx, whereas in patients with advanced PD, levodopa induced significant upregulation of L-[11C]DOPA influx. These changes were confined to the putamen and were, in both patient categories, most prominent in the dorsal part of the region. The present investigation demonstrates a marked shift in the modulatory action of levodopa with the advancement of PD and suggests the induction of positive feedback in advanced PD. These findings could help explain the less graded clinical response to levodopa in advanced PD and would thus have importance for the understanding of the pathogenesis underlying motor fluctuations. 相似文献