全文获取类型
收费全文 | 3898篇 |
免费 | 511篇 |
国内免费 | 256篇 |
专业分类
耳鼻咽喉 | 55篇 |
儿科学 | 37篇 |
妇产科学 | 57篇 |
基础医学 | 237篇 |
口腔科学 | 26篇 |
临床医学 | 447篇 |
内科学 | 410篇 |
皮肤病学 | 50篇 |
神经病学 | 209篇 |
特种医学 | 87篇 |
外国民族医学 | 3篇 |
外科学 | 384篇 |
综合类 | 854篇 |
预防医学 | 241篇 |
眼科学 | 140篇 |
药学 | 417篇 |
1篇 | |
中国医学 | 678篇 |
肿瘤学 | 332篇 |
出版年
2024年 | 47篇 |
2023年 | 253篇 |
2022年 | 397篇 |
2021年 | 396篇 |
2020年 | 436篇 |
2019年 | 176篇 |
2018年 | 158篇 |
2017年 | 156篇 |
2016年 | 126篇 |
2015年 | 147篇 |
2014年 | 347篇 |
2013年 | 334篇 |
2012年 | 336篇 |
2011年 | 319篇 |
2010年 | 246篇 |
2009年 | 196篇 |
2008年 | 105篇 |
2007年 | 113篇 |
2006年 | 82篇 |
2005年 | 32篇 |
2004年 | 23篇 |
2003年 | 24篇 |
2002年 | 23篇 |
2001年 | 25篇 |
2000年 | 13篇 |
1999年 | 13篇 |
1998年 | 20篇 |
1997年 | 16篇 |
1996年 | 14篇 |
1995年 | 9篇 |
1994年 | 1篇 |
1993年 | 8篇 |
1992年 | 10篇 |
1991年 | 6篇 |
1990年 | 11篇 |
1989年 | 8篇 |
1988年 | 10篇 |
1987年 | 6篇 |
1986年 | 5篇 |
1985年 | 1篇 |
1984年 | 6篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有4665条查询结果,搜索用时 15 毫秒
51.
52.
In recent years, deep learning as a state-of-the-art machine learning technique has made great success in histopathological image classification. However, most of deep learning approaches rely heavily on the substantial task-specific annotations, which require experienced pathologists’ manual labelling. As a result, they are laborious and time-consuming, and many unlabeled pathological images are difficult to use without experts’ annotations. To mitigate the requirement for data annotation, we propose a self-supervised Deep Adaptive Regularized Clustering (DARC) framework to pre-train a neural network. DARC iteratively clusters the learned representations and utilizes the cluster assignments as pseudo-labels to learn the parameters of the network. To learn feasible representations and encourage the representations to become more discriminative, we design an objective function combining a network loss with a clustering loss using an adaptive regularization function, which is updated adaptively throughout the training process to learn feasible representations. The proposed DARC is evaluated on three public datasets, including NCT-CRC-HE-100K, PCam and LC25000. Compared to the strategy of training from scratch, fine-tuning using the pre-trained weights of DARC can obviously boost the accuracy of neural networks on histopathological classification. The accuracy of using the network trained using DARC pre-trained weights with only 10% labeled data is already comparable to the network trained from scratch with 100% training data. The network using DARC pre-trained weights achieves the fastest convergence speed on the downstream classification task. Moreover, visualization through t-distributed stochastic neighbor embedding (t-SNE) shows that the learned representations are generalizable and discriminative. 相似文献
53.
目的鼻咽癌作为我国南部地区常见的恶性肿瘤,对人类健康及生命带来了极大的危害,鼻咽癌的病理及解剖特性决定了其以放射治疗为主的治疗方法,鼻咽癌的分期与患者的预后密切相关,因此早期干预可以极大地提高患者的远期生存率,而寻找合适的筛查手段对鼻咽癌的早期发现至关重要,基于此,本文对鼻咽癌的早期筛查的研究新进展作一综述。 相似文献
54.
Antiretroviral therapy improves neurocognitive impairment in people living with HIV? A meta-analysis
《国际护理科学(英文)》2020,7(2):238-247
ObjectivesAlthough effective antiretroviral therapy (ART) has been used for more than two decades, HIV-associated neurocognitive disorder remains prevalent. Thus, whether ART can improve neurocognitive impairment is controversial. This review aims to explore the effects of ART on cognitive impairment in people living with HIV (PLWH).MethodsA systematic literature search was conducted in eight databases (PubMed, Embase, Web of Science, Cochrane Library, CNKI, VIP, China Biology Medicine disc, and WanFang) to identify studies that compare cognitive function between study groups who are administered and not administered ART. We searched for articles published up to April 2019. Article evaluation and data extraction were independently conducted by two reviewers.ResultsSixteen articles (6,694 participants)—14 cross-sectional studies and 2 cohort studies—were included in this meta-analysis. The cross-sectional studies demonstrated that ART group did not perform better than the non-ART group (OR = 1.16; 95% CI, 1.03–1.30). However, the cohort studies reported a significant improvement in cognitive function at three months (OR = 4.01; 95% CI, 2.35–6.85) and six months (OR = 9.24; 95% CI, 1.71–49.96) after ART initiation compared with the baseline data. No significant cognitive improvement was found in participants younger than 55 years old, but the two cross-sectional studies showed that ART may improve cognitive function in PLWH under 65 years old with poor physical condition and immune status.ConclusionsART could improve cognitive function in PLWH with poor physical condition and immune status, but it does not considerably improve cognition in the entire PLWH population. 相似文献
55.
《Neuro-Chirurgie》2022,68(6):e75-e83
BackgroundHydrocephalus is a frequent neurological condition, commonly treated by ventriculoperitoneal shunting (VPS), a neurosurgical procedure with significant risk of infection. Some severely brain-injured hydrocephalic patients with swallowing dysfunction may require percutaneous endoscopic gastrostomy (PEG). There are few data on the safety of PEG in patients with VPS, with contradictory results reported.ObjectiveThe aim of this systematic review and meta-analysis was to determine the rate of VPS infection in the setting of PEG.MethodsSix databases were searched for the period January 1990 to June 2022. Only original articles reporting the rate of shunt infection in the setting of PEG in adults were included. Random-effects meta-analysis was used to assess the rate of infection.ResultsFifteen of the 1,703 identified articles were selected, reporting 701 internal cerebrospinal fluid shunts, with 63 infections. The pooled rate of infection in patients with both PEG and VPS was 7.41% (95% CI [3.67–14.38]). There was a significantly higher risk of VPS infection in the PEG group vs. the control group with VPS without PEG: relative risk (RR) = 2.33 (95% CI [1.11–4.89]). On the other hand, the risk of infection was the same whether the PEG was placed before or after the VPS surgery: RR = 1.05 (95% CI [0.57–1.92]).ConclusionGastrostomy tube placement is a significant risk factor for VPS infection. However, onset of infection was not related to the sequence of or interval between VPS and PEG.Trial registrationThis meta-analysis is registered in https://www.crd.york.ac.uk/PROSPERO/, PROSPERO ID: CRDCRD42022326774. 相似文献
56.
《The journal of sexual medicine》2014,11(12):3102-3111
IntroductionSexual dysfunction has only recently been recognized as a highly prevalent side effect of adjuvant aromatase inhibitor (AI) therapy for breast cancer.AimsA cross‐sectional survey using standardized measures of female sexual function was designed to provide a detailed view of sexual problems during the first 2 years of adjuvant AI therapy and secondarily to examine whether sexual dysfunction leads to nonadherence to this therapy.MethodsQuestionnaires were mailed to all 296 women in a breast oncology registry who had been prescribed a first‐time AI for localized breast cancer 18–24 months previously.Main Outcome MeasuresItems assessed medication adherence, demographic, and medical information. Scales included the Female Sexual Function Index, the Menopausal Sexual Interest Questionnaire, the Female Sexual Distress Scale‐Revised, the Breast Cancer Prevention Trial Eight Symptom Scale to assess menopausal symptoms, and the Merck Adherence Estimator®.ResultsQuestionnaires were returned by 129 of 296 eligible women (43.6%). Respondents were 81% non‐Hispanic white with a mean age of 63 and 48% had at least a college degree. Only 15.5% were nonadherent. Ninety‐three percent of women scored as dysfunctional on the Female Sexual Function Index, and 75% of dysfunctional women were distressed about sexual problems. Although only 52% of women were sexually active when starting their AI, 79% of this group developed a new sexual problem. Fifty‐two percent took action to resolve it, including 24% who stopped partner sex, 13% who changed hormone therapies, and 6% who began a vaginal estrogen. Scores on the Adherence Estimator (beliefs about efficacy, value, and cost of medication) were significantly associated with adherence (P = 0.0301) but sexual function was not.ConclusionsThe great majority of women taking AIs have sexual dysfunction that is distressing and difficult to resolve. Most continue their AI therapy, but a large minority cease sexual activity. Schover LR, Baum GP, Fuson LA, Brewster A, and Melhem‐Bertrandt A. Sexual problems during the first 2 years of adjuvant treatment with aromatase inhibitors. J Sex Med 2014;11:3102–3111. 相似文献
58.
《Clinical Lymphoma, Myeloma & Leukemia》2014,14(1):43-49
BackgroundElevated levels of serum ferritin have been documented to be an adverse prognostic factor in patients with hematologic malignancies undergoing hematopoietic stem cell transplantation. The purpose of this study was to estimate the correlation between elevated levels of serum ferritin and survival outcomes in patients with non-Hodgkin lymphoma (NHL).Patients and MethodsA total of 267 patients who were newly diagnosed with NHL and who received chemotherapy between September 1999 and April 2012 were retrospectively analyzed.ResultsIn multivariate analysis, other chemotherapy regimens excluding CHOP-like chemotherapy regimens (cyclophosphamide, adriamycin, vincristine, prednisolone) and RCHOP (rituximab plus CHOP), a high level of β2-microglobulin, a high-intermediate/high risk according to the international prognostic index (IPI), and elevated levels of serum ferritin were all significant independent prognostic factors for 5-year progression-free survival rates. RCHOP and other chemotherapy regimens, a high level of β2-microglobulin, a high-intermediate/high IPI risk, and high levels of serum ferritin were significant independent prognostic factors for 5-year overall survival rates.ConclusionElevated levels of serum ferritin of 500 ng/mL or more as well as the use of chemotherapy regimens besides CHOP-like or RCHOP, a high-intermediate/high risk IPI, and a high level of beta2-microglobulin in NHL may be an important marker for predicting poor survival outcomes. 相似文献
59.
ObjectiveEpilepsy is a chronic disease with an increased risk of stigma. The aim of this study was to investigate the efficacy of a scale developed by the authors to determine the level of stigma in Turkish patients with epilepsy and their relatives.MethodsIn this pilot study, two scales were developed, one consisting of 32 questions for the patients and one of 20 questions for the patients' relatives. Initially, a total of 30 patients with epilepsy and 30 relatives of the patients were included. The Cronbach's alpha coefficient was calculated in a reliability analysis of validity applying the scales to 302 patients and 201 relatives of the patients. The Pearson correlation coefficient was used for the reliability analysis of the test-retest. The t-test was used in paired series, and factor analysis was conducted. The correlation between the clinical and demographical data and the stigma scores was evaluated.ResultsThe scales were applied to participants twice under the same conditions in one-week interval. In the test-retest analysis, the internal consistency of the scales was high and reliable. In the analysis of the patients, the Cronbach's alpha value of the scale was found to be 0.915. In the factor analysis, the questions were grouped into five factors including social isolation, discrimination, insufficiency, false beliefs, and stigma resistance. The factors with the highest contribution to the stigma level were social isolation and discrimination. In the stigma scores, a significant correlation was found between the age of the patient, frequency of seizures, education status, level of income, and the amount of antiepileptic drugs used. In the analysis of the patients' relatives, the Cronbach's alpha value of the scale was found to be 0.892. In the factor analysis, the questions were classified as discrimination, prejudgments, and false beliefs. The factor which most contributed to the stigma level was discrimination. A significant correlation was found in the stigma scores between sex, education status, marital status, and income distribution.ConclusionAccording to our study results, it is clearly seen that both patients and their relatives suffer from epilepsy-associated stigma. Patients with epilepsy and their relatives are faced with discrimination in society, resulting in social isolation. We, therefore, believe that both patients and their relatives should be informed in detail about discrimination to overcome this challenge. 相似文献
60.