全文获取类型
收费全文 | 4068篇 |
免费 | 270篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 25篇 |
儿科学 | 106篇 |
妇产科学 | 76篇 |
基础医学 | 555篇 |
口腔科学 | 76篇 |
临床医学 | 423篇 |
内科学 | 945篇 |
皮肤病学 | 57篇 |
神经病学 | 518篇 |
特种医学 | 62篇 |
外国民族医学 | 1篇 |
外科学 | 420篇 |
综合类 | 38篇 |
一般理论 | 1篇 |
预防医学 | 380篇 |
眼科学 | 41篇 |
药学 | 264篇 |
中国医学 | 6篇 |
肿瘤学 | 358篇 |
出版年
2023年 | 40篇 |
2022年 | 88篇 |
2021年 | 163篇 |
2020年 | 94篇 |
2019年 | 129篇 |
2018年 | 141篇 |
2017年 | 95篇 |
2016年 | 117篇 |
2015年 | 122篇 |
2014年 | 191篇 |
2013年 | 197篇 |
2012年 | 330篇 |
2011年 | 332篇 |
2010年 | 159篇 |
2009年 | 178篇 |
2008年 | 231篇 |
2007年 | 253篇 |
2006年 | 249篇 |
2005年 | 187篇 |
2004年 | 196篇 |
2003年 | 202篇 |
2002年 | 177篇 |
2001年 | 26篇 |
2000年 | 32篇 |
1999年 | 30篇 |
1998年 | 27篇 |
1997年 | 28篇 |
1996年 | 20篇 |
1995年 | 18篇 |
1994年 | 19篇 |
1993年 | 17篇 |
1992年 | 12篇 |
1991年 | 12篇 |
1990年 | 9篇 |
1989年 | 8篇 |
1988年 | 13篇 |
1987年 | 16篇 |
1986年 | 10篇 |
1985年 | 15篇 |
1984年 | 13篇 |
1983年 | 9篇 |
1982年 | 8篇 |
1981年 | 11篇 |
1979年 | 9篇 |
1977年 | 9篇 |
1976年 | 7篇 |
1974年 | 10篇 |
1969年 | 14篇 |
1968年 | 13篇 |
1967年 | 9篇 |
排序方式: 共有4352条查询结果,搜索用时 406 毫秒
31.
32.
33.
Nora Franceschini Kari E North Jeffrey B Kopp Louise McKenzie Cheryl Winkler 《Genetics in medicine》2006,8(2):63-75
Nephrotic syndrome, characterized by edema, proteinuria, hyperlipidemia and low serum albumin, is a manifestation of kidney disease involving the glomeruli. Nephrotic syndrome may be caused by primary kidney disease such as focal segmental glomerulosclerosis. Mutations in the podocin gene, NPHS2, have been shown in familial and sporadic forms of steroid-resistant nephrotic syndrome, including focal segmental glomerulosclerosis. Podocin is an integral membrane protein located at the slit diaphragm of the glomerular permeability barrier. Complete information is lacking for the population frequency of some NPHS2 variants for all racial and ethnic groups. The most frequently reported variant, R229Q, is more common among European-derived populations than African-derived populations. We calculated crude odds ratios and 95% confidence intervals of childhood nephrotic syndrome and focal segmental glomerulosclerosis associated with R229Q heterozygosity using data from five studies. The R229Q variant is not associated with focal segmental glomerulosclerosis in the US population of African descent. In contrast, the R229Q variant is associated with a trend toward increased focal segmental glomerulosclerosis risk in European-derived populations, with an estimated increased risk of 20-40%. Our insight into the association between NPHS2 variants and nephrotic disease is hampered by the limitations of the existing studies, including small numbers of affected individuals and suboptimal control groups. Nevertheless, the available data suggest that large epidemiological case-control studies to examine the association between NPHS2 variants and nephrotic syndrome are warranted. 相似文献
34.
Pravin C. Singhal Mohan Pamarthi Robin Shah Dev Chandra Nora Gibbons 《Inflammation》1994,18(3):293-299
Focal glomerulosclerosis is the predominant glomerular lesion in heroin addicts. We studied whether morphine, a metabolite of heroin, could directly affect the formation of superoxide by glomerular mesangial cells. Mesangial cells preincubated with morphine (10–8 M) showed a higher (P<0.001) production of superoxide when compared to control cells (control) 401±21 vs. morphine 610±41 nM/mg protein/h). This effect of morphine on mesangial cells was dose dependent. Naloxone, an opiate antagonist, attenuated morphine-induced formation of Superoxide by mesangial cells [control, 317±4; morphine (10–8 M), 573±9; and naloxone (10–8 M) + morphine (10–8 M), 333±6 nM/mg protein/h]. We conclude that morphine enhances formation of superoxide by mesangial cells and this effect of morphine seems to be mediated through opiate receptors. Since superoxide has been demonstrated to cause mesangiolysis, we propose that morphine may be playing a role in the induction of mesangial injury in patients with opiate abuse.This work was supported by National Institute of Health Grant R01-DA-06753. 相似文献
35.
The induction of autoimmunity by viruses has been hypothesized to occur by a number of mechanisms. Coxsackievirus B4 (CB4) induces hyperglycemia in SJL mice resembling diabetes in humans. While virus is effectively cleared within 2 weeks, hyperglycemia does not appear until about 8-12 weeks postinfection at a time when replicative virus is no longer detectable. In SJL mice, reinfection with CB4 enhanced the development of hyperglycemia. As predicted, the immune system responded more rapidly to the second infection and virus was cleared more swiftly. However, while infiltrating T cells were found within the pancreas, depletion of the CD4 T cell population prior to secondary infection or use of CD8 knock-out mice had no effect on the development of virus-mediated hyperglycemia. In conclusion, enhanced hyperglycemia induced by CB4 occurs independent of the T cell response. 相似文献
36.
Jacqueline K Trupiano Kim R Geisinger Mark C Willingham Paul Manders Nora Zbieranski Doug Case Edward A Levine 《Modern pathology》2004,17(4):476-481
Diffuse malignant mesothelioma of the peritoneum is a rare diagnosis. Despite many histopathologic similarities between peritoneal and pleural tumors, clinical and prognostic features may be quite different. There is a paucity of data evaluating molecular features of peritoneal mesotheliomas. Therefore, we compared the results of a battery of immunohistochemical markers, some with therapeutic implications, in patients with primary peritoneal or pleural mesotheliomas. We examined 24 peritoneal and nine pleural malignant mesotheliomas with a battery of immunohistochemical markers (cytokeratin AE1/3, calretinin, c-kit/CD117, desmin, epidermal growth factor receptor (EGFR), estrogen receptors (ER), progesterone receptors (PR), MIB-1, and cleaved caspase-3) in an attempt to distinguish any differences in this tumor arising in these two distinct locations. The results indicate that the only marker to show a significant difference in its staining pattern between these two sites was EGFR (P=0.0004). In all, 92% (22/24) of peritoneal tumors demonstrated 3+ or 4+ immunoreactivity with EGFR, opposed to only 33% (3/9) pleural tumors. There was no significant difference in immunoreactivity between the pleural and peritoneal tumors with c-kit, ER, PR, cleaved caspase 3, calretinin, and desmin. There was a trend toward increased cytokeratin (P=0.07) and MIB-1 (P=0.08) expression in the peritoneal group. There was no significant difference in age, sex, or histologic subtype between the two locations. In conclusion, despite similarities between peritoneal and pleural mesothelioma, there are differences between this neoplasm arising in these two sites. The EGFR expression is more pronounced in peritoneal tumors compared to pleural tumors. The increased expression of EGFR in the peritoneal lesions may be of clinical significance with the recent emergence of epidermal growth factor receptor-targeted therapies. 相似文献
37.
38.
Characteristics of very poor outcome schizophrenia 总被引:2,自引:0,他引:2
R S Keefe R C Mohs M F Losonczy M Davidson J M Silverman K S Kendler T B Horvath R Nora K L Davis 《The American journal of psychiatry》1987,144(7):889-895
The authors compared 21 "Kraepelinian" schizophrenic patients who had been ill and dependent on others for the past 5 years with 76 chronic schizophrenic patients in remission or with exacerbations requiring hospitalization. The Kraepelinian patients met the criteria for schizophrenia by more diagnostic systems than the exacerbated patients, were less responsive to haloperidol, had more severe negative symptoms, and had similarly severe positive symptoms. They had cerebral ventricles that were more asymmetrical and a greater family history of schizophrenia spectrum disorders than the other chronic patients. These data suggest that patients with 5 years of illness and complete dependency on others may represent a subgroup of schizophrenia. 相似文献
39.
40.
Joanna Paladino Suzanne Mitchell Namita Mohta Joshua R. Lakin Nora Downey Erik K. Fromme Sue Gullo Evan Benjamin Justin J. Sanders 《Joint Commission journal on quality and patient safety / Joint Commission Resources》2021,47(2):127-136
The COVID-19 pandemic has exposed the medical and social vulnerability of an unprecedented number of people. Consequently, there has never been a more important time for clinicians to engage patients in advance care planning (ACP) discussions about their goals, values, and preferences in the event of critical illness. An evidence-based communication tool—the Serious Illness Conversation Guide—was adapted to address COVID-related ACP challenges using a user-centered design process: convening relevant experts to propose initial guide adaptations; soliciting feedback from key clinical stakeholders from multiple disciplines and geographic regions; and iteratively testing language with patient actors. With feedback focused on sharing risk about COVID-19–related critical illness, recommendations for treatment decisions, and use of person-centered language, the team also developed conversation guides for inpatient and outpatient use. These tools consist of open-ended questions to elicit perception of risk, goals, and care preferences in the event of critical illness, and language to convey prognostic uncertainty. To support use of these tools, publicly available implementation materials were also developed for clinicians to effectively engage high-risk patients and overcome challenges related to the changed communication context, including video demonstrations, telehealth communication tips, and step-by-step approaches to identifying high-risk patients and documenting conversation findings in the electronic health record. Well-designed communication tools and implementation strategies can equip clinicians to foster connection with patients and promote shared decision making. Although not an antidote to this crisis, such high-quality ACP may be one of the most powerful tools we have to prevent or ameliorate suffering due to COVID-19. 相似文献