全文获取类型
收费全文 | 11330篇 |
免费 | 735篇 |
国内免费 | 34篇 |
专业分类
耳鼻咽喉 | 93篇 |
儿科学 | 356篇 |
妇产科学 | 339篇 |
基础医学 | 1556篇 |
口腔科学 | 389篇 |
临床医学 | 1681篇 |
内科学 | 1875篇 |
皮肤病学 | 167篇 |
神经病学 | 1007篇 |
特种医学 | 200篇 |
外科学 | 992篇 |
综合类 | 111篇 |
一般理论 | 10篇 |
预防医学 | 1621篇 |
眼科学 | 191篇 |
药学 | 807篇 |
1篇 | |
中国医学 | 20篇 |
肿瘤学 | 683篇 |
出版年
2023年 | 68篇 |
2022年 | 126篇 |
2021年 | 257篇 |
2020年 | 185篇 |
2019年 | 255篇 |
2018年 | 331篇 |
2017年 | 219篇 |
2016年 | 293篇 |
2015年 | 301篇 |
2014年 | 433篇 |
2013年 | 596篇 |
2012年 | 905篇 |
2011年 | 941篇 |
2010年 | 544篇 |
2009年 | 489篇 |
2008年 | 816篇 |
2007年 | 830篇 |
2006年 | 781篇 |
2005年 | 729篇 |
2004年 | 668篇 |
2003年 | 566篇 |
2002年 | 560篇 |
2001年 | 89篇 |
2000年 | 58篇 |
1999年 | 97篇 |
1998年 | 105篇 |
1997年 | 85篇 |
1996年 | 61篇 |
1995年 | 65篇 |
1994年 | 50篇 |
1993年 | 56篇 |
1992年 | 46篇 |
1991年 | 25篇 |
1990年 | 35篇 |
1989年 | 43篇 |
1988年 | 42篇 |
1987年 | 33篇 |
1986年 | 22篇 |
1985年 | 35篇 |
1984年 | 35篇 |
1983年 | 33篇 |
1982年 | 21篇 |
1981年 | 29篇 |
1980年 | 27篇 |
1979年 | 30篇 |
1978年 | 14篇 |
1977年 | 9篇 |
1976年 | 9篇 |
1974年 | 11篇 |
1972年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
71.
Regan N Theiler Angela M Caliendo Sabine Pargman B Denise Raynor Sarah Berga Melissa McPheeters Denise J Jamieson 《Journal of clinical virology》2006,37(4):313-316
BACKGROUND: Cytomegalovirus (CMV) infection, which is the most common congenitally transmitted infection, affects approximately 1% of neonates worldwide. Despite its prevalence, no convenient screening test for neonatal CMV infection has been implemented. OBJECTIVE: The purpose of this pilot study was to evaluate the feasibility and yield of screening umbilical cord blood for CMV DNA emiaby quantitative PCR. STUDY DESIGN: Umbilical cord blood was tested for CMV DNAemia using a commercial quantitative PCR assay. Maternal CMV serostatus at the time of delivery was assessed by testing for CMV IgG and IgM antibodies in serum. CONCLUSIONS: Screening for congenital CMV infection with PCR is easily incorporated into routine labor and delivery care using discarded cord blood specimens to identify neonates whose infection is otherwise undiagnosed. Among 433 infants tested, two (0.5%) had DNAemia detected in cord blood, one of whom was symptomatic, and both of whose mothers were CMV IgG positive and IgM negative. Viremic neonates identified by screening with PCR may be at high risk of developing long-term neurological complications of CMV infection and cannot reliably be identified using clinical presentation or maternal serology. Because of its convenience, cord blood CMV screening with PCR should be further investigated for incorporation into neonatal screening protocols. 相似文献
72.
Asher Y. Rosinger Samantha M. Olson Sascha R. Ellington Janice Perez-Padilla Regina M. Simeone Caitlin S. Pedati Betsy A. Schroeder Gilberto A. Santiago Freddy A. Medina Jorge L. Muoz-Jordn Laura E. Adams Romeo R. Galang Miguel Valencia-Prado Sonia Bakkour Candimar Coln Mary Goodwin Dana Meaney-Delman Jennifer S. Read Lyle R. Petersen Denise J. Jamieson Carmen C. Deseda Margaret A. Honein Brenda Rivera-García Carrie K. Shapiro-Mendoza 《Emerging infectious diseases》2021,27(5):1505
We evaluated nucleic acid amplification testing (NAAT) for Zika virus on whole-blood specimens compared with NAAT on serum and urine specimens among asymptomatic pregnant women during the 2015–2016 Puerto Rico Zika outbreak. Using NAAT, more infections were detected in serum and urine than in whole blood specimens. 相似文献
73.
Robison Valerie Bauman Brenda D’Angelo Denise V. Espinoza Lorena Thornton-Evans Gina Lin Mei 《Maternal and child health journal》2021,25(5):832-840
Maternal and Child Health Journal - To measure the association between dental and medical insurance with the receipt of dental cleaning during pregnancy. We analyzed Pregnancy Risk Assessment... 相似文献
74.
Providing Hearing Assistance to Low-Income Adults at Risk for Social Isolation: Preliminary Findings
75.
Anania Pasquale Battaglini Denise Balestrino Alberto DAndrea Alessandro Prior Alessandro Ceraudo Marco Rossi Diego Criminelli Zona Gianluigi Fiaschi Pietro 《Neurosurgical review》2021,44(3):1243-1253
Neurosurgical Review - Posterior cranial fossa tumours frequently develop hydrocephalus as first presentation in up to 80% of paediatric patients and 21.4% of adults, although it resolves after... 相似文献
76.
Marysol Luna Jason D Guss Laura S Vasquez-Bolanos Macy Castaneda Manuela Vargas Rojas Jasmin M Strong Denise A Alabi Sophie D Dornevil Jacob C Nixon Erik A Taylor Eve Donnelly Xueyan Fu M Kyla Shea Sarah L Booth Rodrigo Bicalho Christopher J Hernandez 《Journal of bone and mineral research》2021,36(9):1823-1834
Modifications to the constituents of the gut microbiome influence bone density and tissue-level strength, but the specific microbial components that influence tissue-level strength in bone are not known. Here, we selectively modify constituents of the gut microbiota using narrow-spectrum antibiotics to identify components of the microbiome associated with changes in bone mechanical and material properties. Male C57BL/6J mice (4 weeks) were divided into seven groups (n = 7–10/group) and had taxa within the gut microbiome removed through dosing with: (i) ampicillin; (ii) neomycin; (iii) vancomycin; (iv) metronidazole; (v) a cocktail of all four antibiotics together (with zero-calorie sweetener to ensure intake); (vi) zero-calorie sweetener only; or (vii) no additive (untreated) for 12 weeks. Individual antibiotics remove only some taxa from the gut, while the cocktail of all four removes almost all microbes. After accounting for differences in geometry, whole bone strength was reduced in animals with gut microbiome modified by neomycin (−28%, p = 0.002) and was increased in the group in which the gut microbiome was altered by sweetener alone (+39%, p < 0.001). Analysis of the fecal microbiota detected seven lower-ranked taxa differentially abundant in animals with impaired tissue-level strength and 14 differentially abundant taxa associated with increased tissue-level strength. Histological and serum markers of bone turnover and trabecular bone volume per tissue volume (BV/TV) did not differ among groups. These findings demonstrate that modifications to the taxonomic components of the gut microbiome have the potential to decrease or increase tissue-level strength of bone independent of bone quantity and without noticeable changes in bone turnover. © 2021 American Society for Bone and Mineral Research (ASBMR). 相似文献
77.
Tanya C. Saraiya Skye Fitzpatrick Kathryn Zumberg‐Smith Teresa Lpez‐Castro Sudie E. Back Denise A. Hien 《Journal of traumatic stress》2021,34(1):56-68
The debate around the construct validity of complex posttraumatic stress disorder (CPTSD) has begun to examine whether CPTSD diverges from posttraumatic stress disorder (PTSD) when it co‐occurs with the diagnosis of borderline personality disorder (BPD). The present study (a) examined the construct validity of CPTSD through a latent class analysis of a non–treatment‐seeking sample of young trauma‐exposed adults and (b) characterized each class in terms of trauma characteristics, social emotions (e.g., shame, guilt, blame), and interpersonal functioning. A total of 23 dichotomized survey items were chosen to represent the symptoms of PTSD, CPTSD, and BPD and administered to 197 trauma‐exposed participants. Fit statistics compared models with 2–4 latent classes. The four‐class model showed the best fit statistics and clinical interpretability. Classes included a “high PTSD+CPTSD+BPD” class, characterized by high‐level endorsement of all symptoms for the three diagnoses; a “moderate PTSD+CPTSD+BPD” class, characterized by endorsement of some symptoms across all three diagnoses; a “PTSD” class, characterized by endorsement of the ICD‐11 PTSD criteria; and a “healthy” class, characterized by low symptom endorsement overall. Pairwise comparisons showed individuals in the high PTSD+CPTSD+BPD class to have the highest levels of psychological distress, traumatic event history, adverse childhood experiences, and PTSD symptoms. Shame was the only social emotion to significantly differ between the classes, p = .002, η² = .16. The findings diverge from the literature, indicating an overlap of PTSD, CPTSD, and BPD symptoms in a non–treatment‐seeking community sample. Further, shame may be a central emotion that differentiates between presentation severities following trauma exposure. 相似文献
78.
79.
Niall Cribben Denise Gonoud Leo G. Kevin 《Anaesthesia and Intensive Care Medicine》2021,22(4):232-237
The purpose of cardiopulmonary bypass is to maintain perfusion and oxygenation of the vital organs in the absence of heart and lung function, usually to facilitate surgery on the heart, but occasionally in other situations. Although the intricacies of the modern extracorporeal circuit and the conduct of cardiopulmonary bypass are the domain of the clinical perfusion scientist (‘perfusionist’), safe surgery mandates a good understanding of some fundamentals by the anaesthetist and the surgeon. This review is aimed at the anaesthetist. First, we will systematically examine the main components of the extracorporeal circuit, travelling in the direction that blood travels, from the venous cannula to the arterial cannula. Then we will describe the process of preparing for bypass, ‘going on’, conducting a bypass run, and weaning and separation from bypass. It is crucial to have clear communication between the surgeon, perfusionist and anaesthetist. This can be difficult for the novice because a quite specific language has evolved in cardiac operating theatres to signal key events in the cardiopulmonary bypass sequence. As we go through this article, we will highlight commonly used terminology and expressions used. 相似文献
80.
Sudeshna Paul Taylor Melanson Sumit Mohan Katherine Ross-Driscoll Laura McPherson Raymond Lynch Denise Lo Stephen O. Pastan Rachel E. Patzer 《American journal of transplantation》2021,21(1):314-321
Kidney transplant program performance in the United States is commonly measured by posttransplant outcomes. Inclusion of pretransplant measures could provide a more comprehensive assessment of transplant program performance and necessary information for patient decision-making. In this study, we propose a new metric, the waitlisting rate, defined as the ratio of patients who are waitlisted in a center relative to the person-years referred for evaluation to a program. Furthermore, we standardize the waitlisting rate relative to the state average in Georgia, North Carolina, and South Carolina. The new metric was used as a proof-of-concept to assess transplant-program access compared to the existing transplant rate metric. The study cohorts were defined by linking 2017 United States Renal Data System (USRDS) data with transplant-program referral data from the Southeastern United States between January 1, 2012 and December 31, 2016. Waitlisting rate varied across the 9 Southeastern transplant programs, ranging from 10 to 22 events per 100 patient-years, whereas the program-specific waitlisting rate ratio ranged between 0.76 and 1.33. Program-specific waitlisting rate ratio was uncorrelated with the transplant rate ratio (r = −.15, 95% CI, −0.83 to 0.57). Findings warrant collection of national data on early transplant steps, such as referral, for a more comprehensive assessment of transplant program performance and pretransplant access. 相似文献