全文获取类型
收费全文 | 8587篇 |
免费 | 973篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 77篇 |
儿科学 | 267篇 |
妇产科学 | 189篇 |
基础医学 | 1193篇 |
口腔科学 | 276篇 |
临床医学 | 994篇 |
内科学 | 1616篇 |
皮肤病学 | 90篇 |
神经病学 | 888篇 |
特种医学 | 253篇 |
外科学 | 1186篇 |
综合类 | 321篇 |
一般理论 | 7篇 |
预防医学 | 1021篇 |
眼科学 | 270篇 |
药学 | 517篇 |
中国医学 | 3篇 |
肿瘤学 | 405篇 |
出版年
2021年 | 131篇 |
2020年 | 107篇 |
2019年 | 152篇 |
2018年 | 156篇 |
2017年 | 135篇 |
2016年 | 114篇 |
2015年 | 135篇 |
2014年 | 187篇 |
2013年 | 329篇 |
2012年 | 401篇 |
2011年 | 429篇 |
2010年 | 226篇 |
2009年 | 214篇 |
2008年 | 377篇 |
2007年 | 387篇 |
2006年 | 391篇 |
2005年 | 379篇 |
2004年 | 363篇 |
2003年 | 283篇 |
2002年 | 315篇 |
2001年 | 278篇 |
2000年 | 272篇 |
1999年 | 252篇 |
1998年 | 90篇 |
1997年 | 86篇 |
1996年 | 87篇 |
1995年 | 76篇 |
1994年 | 74篇 |
1993年 | 71篇 |
1992年 | 206篇 |
1991年 | 180篇 |
1990年 | 204篇 |
1989年 | 200篇 |
1988年 | 189篇 |
1987年 | 147篇 |
1986年 | 150篇 |
1985年 | 159篇 |
1984年 | 112篇 |
1983年 | 108篇 |
1982年 | 75篇 |
1981年 | 60篇 |
1979年 | 115篇 |
1978年 | 96篇 |
1977年 | 78篇 |
1976年 | 65篇 |
1975年 | 60篇 |
1974年 | 71篇 |
1973年 | 95篇 |
1972年 | 87篇 |
1971年 | 75篇 |
排序方式: 共有9573条查询结果,搜索用时 46 毫秒
1.
Victoria L. Parker Matthew C. Winter John A. Tidy Barry W. Hancock Julia E. Palmer Naveed Sarwar Baljeet Kaur Katie McDonald Xianne Aguiar Kamaljit Singh Nick Unsworth Imran Jabbar Allan A. Pacey Robert F. Harrison Michael J. Seckl 《International journal of cancer. Journal international du cancer》2023,152(5):986-997
Gestational trophoblastic neoplasia (GTN) patients are treated according to the eight-variable International Federation of Gynaecology and Obstetrics (FIGO) scoring system, that aims to predict first-line single-agent chemotherapy resistance. FIGO is imperfect with one-third of low-risk patients developing disease resistance to first-line single-agent chemotherapy. We aimed to generate simplified models that improve upon FIGO. Logistic regression (LR) and multilayer perceptron (MLP) modelling (n = 4191) generated six models (M1-6). M1, all eight FIGO variables (scored data); M2, all eight FIGO variables (scored and raw data); M3, nonimaging variables (scored data); M4, nonimaging variables (scored and raw data); M5, imaging variables (scored data); and M6, pretreatment hCG (raw data) + imaging variables (scored data). Performance was compared to FIGO using true and false positive rates, positive and negative predictive values, diagnostic odds ratio, receiver operating characteristic (ROC) curves, Bland-Altman calibration plots, decision curve analysis and contingency tables. M1-6 were calibrated and outperformed FIGO on true positive rate and positive predictive value. Using LR and MLP, M1, M2 and M4 generated small improvements to the ROC curve and decision curve analysis. M3, M5 and M6 matched FIGO or performed less well. Compared to FIGO, most (excluding LR M4 and MLP M5) had significant discordance in patient classification (McNemar's test P < .05); 55-112 undertreated, 46-206 overtreated. Statistical modelling yielded only small gains over FIGO performance, arising through recategorisation of treatment-resistant patients, with a significant proportion of under/overtreatment as the available data have been used a priori to allocate primary chemotherapy. Streamlining FIGO should now be the focus. 相似文献
2.
P M Doraiswamy K R Krishnan O B Boyko M M Husain G S Figiel V J Palese P R Escalona S A Shah W M McDonald W J Rockwell 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(3):351-356
1. The frequent occurrence of hypothalamo-pituitary dysfunction in patients with eating disorders as well as prior reports that nutritional and endocrine status influence pituitary morphology, led us to hypothesize that pituitary size and shape may be altered in patients with eating disorders. 2. Magnetic resonance imaging (MRI) does not use ionizing radiation and is currently one of the most feasible modalities available to study the pituitary gland in vivo. Using MRI, we have previously reported in a preliminary study that female patients with eating disorders had significantly smaller pituitary glands than controls. In addition MRI excluded any pituitary mass lesions. 3. In this report, we confirm our previous MRI findings and provide further evidence of pituitary abnormalities in an expanded sample of eating disorder patients. Preliminary data on pituitary volume estimates from MRI scans are provided for a subset of patients and controls. 相似文献
3.
Optic nerve glioma and the management of optic nerve tumours in the young. 总被引:4,自引:0,他引:4
下载免费PDF全文
![点击此处可从《The British journal of ophthalmology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Thirty-one patients presenting as orbital optic nerve glioma have been reviewed with maximum follow-up of 14 years. Sixteen of these patients have been reported on previously and further follow-up is provided. Sixteen patients had a stable clinical course with little change over a period of up to 13.5 years. Neurofibromatosis was relatively common in this group (11/16). Fifteen patients had progressive enlargement of the tumour; the incidence of neurofibromatosis in this group was low (4/15). Eleven of these patients were explored neurosurgically and the optic nerve totally excised in 10 of them. The proximal cut end was normal in six patients and the chiasm has apparently remained free of tumour in all of them. We suggest a method of management of primary optic nerve tumours, both meningiomas and gliomas, in young patients. 相似文献
4.
5.
J W McDonald E A Garofalo T Hood J C Sackellares S Gilman P E McKeever J C Troncoso M V Johnston 《Annals of neurology》1991,29(5):529-541
We examined binding to excitatory amino acid and inhibitory amino acid receptors in frozen hippocampal sections prepared from surgical specimens resected from 8 individuals with medically refractory temporal lobe epilepsy. The excitatory receptors studied included N-methyl-D-aspartate (NMDA), strychnine-insensitive glycine, phencyclidine, and quisqualate. The inhibitory receptors studied were gamma-aminobutyric acid type A (GABAA) and benzodiazepine. Excitatory and inhibitory amino acid receptor binding were differentially altered in the patients with temporal lobe epilepsy in comparison to 8 age-comparable autopsy control subjects, and changes in receptor binding were regionally selective in four areas. Binding to phencyclidine receptors associated with the NMDA channel was reduced by 35 to 70% in all regions in the hippocampi of the patients. In contrast, binding to the NMDA recognition site and its associated glycine modulatory site was elevated by 20 to 110% in the cornu ammonis (CA) 1 area and dentate gyrus of the hippocampus of the patients. Binding to these sites was unaffected in area CA4. Binding to the quisqualate-type excitatory amino acid receptor was unchanged in all regions except the stratum lacunosum moleculare CA1, where it was increased by 63%. GABAA and benzodiazepine receptor binding was reduced by 20 to 60% in CA1 and CA4, but unchanged in dentate gyrus. The data indicate that excitatory and inhibitory amino acid receptors are altered in the hippocampus of patients with temporal lobe epilepsy. 相似文献
6.
Penny H Feldman Christopher M Murtaugh Liliana E Pezzin Margaret V McDonald Timothy R Peng 《Health services research》2005,40(3):865-886
OBJECTIVE: To assess the impact and cost-effectiveness of two information-based provider reminder interventions designed to improve self-care management and outcomes of heart failure (HF) patients. DATA SOURCES/STUDY SETTING: Interview and agency administrative data on 628 home care patients with a primary diagnosis of HF. STUDY DESIGN: Patients were treated by nurses randomly assigned to usual care or one of two intervention groups. The basic intervention was an e-mail to the patient's nurse highlighting six HF-specific clinical recommendations. The augmented intervention supplemented the initial nurse reminder with additional clinician and patient resources. DATA COLLECTION: Patient interviews were conducted 45 days post admission to measure self-management behaviors, HF-specific outcomes (Kansas City Cardiomyopathy Questionnaire-KCCQ), health-related quality of life (EuroQoL), and service use. PRINCIPAL FINDINGS: Both interventions improved the mean KCCQ summary score (15.3 and 12.9 percent, respectively) relative to usual care (p< or =.05). The basic intervention also yielded a higher EuroQoL score relative to usual care (p< or =.05). In addition, the interventions had a positive impact on medication knowledge, diet, and weight monitoring. The basic intervention was more cost-effective than the augmented intervention in improving clinical outcomes. CONCLUSIONS: This study demonstrates the positive impact of targeting evidence-based computer reminders to home health nurses to improve patient self-care behaviors, knowledge, and clinical outcomes. It also advances the field's limited understanding of the cost-effectiveness of selected strategies for translating research into practice. 相似文献
7.
Ruth McDonald BA MSc PhD Stephen Harrison BSc MPhil PhD 《Health & social care in the community》2004,12(3):194-201
Recent New Labour policy for the ‘modernisation’ of Government places a good deal of emphasis on decentralisation. This emphasis is particularly marked in relation to the organisation of primary care. However, like hospitals and other National Health Service institutions, primary care trusts (PCTs) are subject to a substantial raft of centrally established performance targets and indicators, including those which contribute to the public award of between zero and three performance ‘stars’. This raises questions about the extent to which employees can exercise autonomy in the context of rigid top‐down directives. This paper presents findings from a study using participant observation and interviews to examine the impact of a training course aimed ostensibly at increasing employee autonomy in an English PCT. The suggestion is that attempts to make employees more autonomous can be seen as a strategy for increasing central control based upon the internalisation by the employees of centrally promulgated values. The attraction of such strategies is that they may be potentially more effective and less costly than alternative strategies of direct control. However, the study suggests that the outcome of attempts by such methods as programmes to increase employee autonomy may be very different from those intended. 相似文献
8.
K L McDonald 《Clinical nuclear medicine》1987,12(2):131-133
Hypervascularity and persistent uptake were demonstrated in a small bowel leiomyoma not actively bleeding at the time of Tc-99m RBC scintigraphy. The potential value of Tc-99m RBC scanning in the evaluation of benign small bowel tumors is discussed. 相似文献
9.
Use of Vicryl (polyglactin 910) mesh to limit epidural scar formation after laminectomy 总被引:1,自引:0,他引:1
A variety of substances have been used at laminectomy sites to prevent postoperative epidural scarring. Free grafts of autologous subcutaneous fat are commonly used both clinically and experimentally. The free fat grafts usually survive, but decrease in size by about 50%. Postoperatively, subcutaneous seroma has been observed with the use of fat grafts, as well as recurrent symptoms of neural compression by the graft that required additional operations. When compared to the use of free grafts after laminectomy in dogs, Vicryl mesh produced slightly more scarring, but consistently less than that observed in control animals. The Vicryl mesh was resorbed by a minimal chronic inflammatory response over about 45 days. Seven of 11 fat-grafted zones showed signs of necrosis, at times with a greater collection of inflammatory cells than that associated with the Vicryl mesh. Of the 4 fat-grafted zones that showed good survival, 2 had gross evidence of neural compression. No surgical zone treated with Vicryl mesh exhibited evidence of neural compression. In view of these results, the use of Vicryl mesh at laminectomy sites may be a safer method of limiting postoperative epidural scar formation. 相似文献
10.