全文获取类型
收费全文 | 1133098篇 |
免费 | 76022篇 |
国内免费 | 3105篇 |
专业分类
耳鼻咽喉 | 15811篇 |
儿科学 | 35701篇 |
妇产科学 | 30634篇 |
基础医学 | 160749篇 |
口腔科学 | 30613篇 |
临床医学 | 101250篇 |
内科学 | 214464篇 |
皮肤病学 | 25449篇 |
神经病学 | 85004篇 |
特种医学 | 45331篇 |
外国民族医学 | 207篇 |
外科学 | 170715篇 |
综合类 | 25737篇 |
现状与发展 | 8篇 |
一般理论 | 274篇 |
预防医学 | 77858篇 |
眼科学 | 25831篇 |
药学 | 91020篇 |
28篇 | |
中国医学 | 4441篇 |
肿瘤学 | 71100篇 |
出版年
2021年 | 9625篇 |
2019年 | 9291篇 |
2018年 | 13175篇 |
2017年 | 10342篇 |
2016年 | 11578篇 |
2015年 | 13482篇 |
2014年 | 18025篇 |
2013年 | 25428篇 |
2012年 | 35099篇 |
2011年 | 36711篇 |
2010年 | 21798篇 |
2009年 | 20300篇 |
2008年 | 33286篇 |
2007年 | 35378篇 |
2006年 | 35862篇 |
2005年 | 33941篇 |
2004年 | 32366篇 |
2003年 | 31077篇 |
2002年 | 29726篇 |
2001年 | 61429篇 |
2000年 | 62641篇 |
1999年 | 51924篇 |
1998年 | 12933篇 |
1997年 | 11404篇 |
1996年 | 11384篇 |
1995年 | 10648篇 |
1994年 | 9649篇 |
1993年 | 9065篇 |
1992年 | 38295篇 |
1991年 | 36691篇 |
1990年 | 36141篇 |
1989年 | 34627篇 |
1988年 | 31176篇 |
1987年 | 30313篇 |
1986年 | 28486篇 |
1985年 | 26684篇 |
1984年 | 19361篇 |
1983年 | 16271篇 |
1982年 | 8913篇 |
1979年 | 17195篇 |
1978年 | 11537篇 |
1977年 | 10312篇 |
1976年 | 8924篇 |
1975年 | 10151篇 |
1974年 | 11732篇 |
1973年 | 11343篇 |
1972年 | 10819篇 |
1971年 | 10154篇 |
1970年 | 9296篇 |
1969年 | 8967篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
Abstract: Background: Few studies have examined in depth the labor progression of multiparas to determine if there is any additional impact of being parous beyond the first birth. The objective of this study was to determine the effect of parity on labor progression in contemporary obstetric practice. Methods: Our sample consisted of all low‐risk women who delivered a term, live‐born infant from January 2002 to March 2004 at a single institution in Delaware, United States (n = 5,589). The median duration of labor by each centimeter of cervical dilation was computed for parity = 0 (n = 2,645); parity = 1 (n = 1,839); parity = 2 (n = 750); and parity = 3 + (n = 355). Results: Multiparas had a significantly faster labor progression from 4 to 10 cm (293, 300, and 313 min, respectively, for parity = 1, parity = 2, and parity = 3 +), compared with nulliparas (383 min for parity = 0), as well as a shorter second stage of labor. However, no significant differences were found in duration of the active phase or the second stage of labor among multiparas. Conclusions: Additional childbearing appears to have no effect of on the progression of labor among multiparous subgroups. The difference in duration of the active phase between nulliparas and multiparas is substantially smaller in a contemporary population. (BIRTH 33:1 March 2006) 相似文献
63.
Elhaji Youssef A.; Stoica Ileana; Dennis Sheldon; Purisima Enrico O.; Lumbroso Rose; Beitel Lenore K.; Trifiro Mark A. 《Human molecular genetics》2006,15(9):1561
Human Molecular Genetics (2006) 15, 921931; 相似文献
64.
PURPOSE: Concern over stigma as a consequence of genetic testing has grown in response to the recent increase in genetic research and testing resulting from the Human Genome Project. However, whether a genetic or hereditary basis necessarily confers a stigma to a condition remains unexamined. METHODS: We performed a qualitative interview study with 86 individuals with one of four conditions: deafness or hearing loss, breast cancer, sickle cell disease, and cystic fibrosis. The first two groups were divided approximately between people who ascribed their conditions to a genetic or hereditary cause and those who did not. RESULTS: Respondents interpreted genetic or hereditary causes and nongenetic causes in a variety of ways. Subjects with breast cancer reported the most consistently negative interpretation of genetic cause. This response concerned future ill health, not an enduring sense of stigma. Deaf and hard of hearing subjects provided the most consistently positive comments about a genetic or hereditary basis to their condition, casting familial hearing loss as a vital component of group and individual identity. Respondents with sickle cell disease and cystic fibrosis offered similar and positive interpretations of the genetic cause of their condition insofar as it meant their conditions were not contagious. CONCLUSIONS: Although some subjects report feeling stigmatized as a result of their condition, this stigmatization is not uniformly associated with the condition's cause, genetic or otherwise. Instead, stigma emerges from a variety of sources in the context of the lived experience of a particular condition. 相似文献
65.
Matthew J Matasar Ellen K Ritchie Nathan Consedine Carol Magai Alfred I Neugut 《European journal of cancer prevention》2006,15(4):367-370
Despite significant improvements in the prognosis of acute promyelocytic leukemia brought about by therapeutic advances, understanding of the epidemiology of acute promyelocytic leukemia remains limited. Earlier reports have suggested that Hispanics may have an increased incidence of acute promyelocytic leukemia, but no systematic analysis of national data has yet been reported. We performed a retrospective cohort study, using data from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute from 1992-2001 in order to compare leukemia incidence rates as a function of race and ethnicity. We identified 709 cases of acute promyelocytic leukemia and analyzed incidence rates by race and sex. Hispanics were not found to have greater lifetime incidence rates than whites, with an incidence relative rate (IRR) of 0.86 that of whites (P=0.17). The age distribution among Hispanics was significantly different from non-Hispanic whites, with greater incidence rates for children ages 1-19 years (IRR=1.9, P=0.02) and adult ages 20-44 years (IRR=1.6, P=0.004). Blacks had lower lifetime incidence rates than non-Hispanic whites (IRR=0.75, P=0.04), Hispanics (IRR=0.64, P=0.007), and Asians (IRR=0.67, P=0.03). Asians did not differ from non-Hispanic whites in lifetime or age-specific incidence rates. These results indicate that while US Hispanics do not have greater lifetime incidence rates of acute promyelocytic leukemia, blacks have lower incidence rates of acute promyelocytic leukemia than Hispanics, non-Hispanic whites, and Asians. 相似文献
66.
Abstract: Background: Identification of risk drinking in expectant fathers may be helpful as an important part of efforts to minimize maternal alcohol use, and as an opportunity to inform them about a problematic practice during a critical developmental stage for the couple. The purpose of this study was to evaluate the T‐ACE screening questionnaire, which asks about t olerance to alcohol, being a nnoyed by other's comments about drinking, attempts to c ut down, and having a drink first thing in the morning (“ e ye‐opener”), in the male partners of pregnant women who themselves were T‐ACE positive. Methods: Two hundred fifty‐four male partners were asked to complete the T‐ACE embedded in a health survey, the Alcohol Use Disorders Identification Test (AUDIT), and other questions about their alcohol use in the past 30 days when their pregnant partners had a median gestation of 11.5 weeks (T1). After delivery, male partners again completed the T‐ACE and quantity‐frequency questions (T2). The predictive ability of the T‐ACE and AUDIT was compared, using risk drinking (>4 drinks/day or >14 drinks/week) as the criterion standard. Results: A substantial minority of male partners had risk drinking, 31 percent at T1 and 25 percent at T2. Although the AUDIT was better than the T‐ACE as an independent predictor of risk drinking, the latter was most accurate when the tolerance threshold exceeded 2 drinks, the same established for pregnant women. The sensitivity (T1 = 84.6%, T2 = 82.8%) and specificity (T1 = 43.8%, T2 = 51.1%) of the T‐ACE at this threshold compared favorably with those of the AUDIT at the standard cut point of 8. Conclusions: The T‐ACE may be a practical way for clinicians to identify risk drinking in both pregnant women and expectant fathers. (BIRTH 33:2 June 2006) 相似文献
67.
J?rg Müller Klaus Seppi Nadia Stefanova Werner Poewe Irene Litvan Gregor K Wenning 《Movement disorders》2002,17(5):1041-1045
The frequency and pathophysiology of freezing of gait (FoG) in atypical parkinsonism is unknown. We analysed the frequency of FoG in postmortem-confirmed atypical parkinsonian disorders (APD) comprising corticobasal degeneration (CBD), dementia with Lewy bodies (DLB), multiple system atrophy (MSA), and progressive supranuclear palsy (PSP). Sixty-six patients with pathologically confirmed APD (CBD, n = 13; DLB, n = 14; MSA, n = 15; PSP, n = 24) formed the basis for a multicenter clinicopathological study. Clinical features at first and last clinical visit were abstracted from patient records on standardized forms following strict instructions. At the first visit (median 36 months after symptom onset), 24% of APD had FoG (CBD, 8%; DLB, 21%; PSP, 25%; MSA, 40%). Logistic regression analysis showed a significant association of FoG and urinary incontinence (P = 0.04) at first visit. At last visit, 47% of APD had FoG (CBD, 25%; PSP, 53%; DLB, 54%; MSA, 54%). Clinicopathological correlation based on routine postmortem examination failed to identify a consistent neuropathological substrate of FoG. This study demonstrates that (1) FoG is common in APD, and (2) urinary incontinence is significantly associated with FoG in these disorders. Whether FoG and urinary incontinence share similar neuropathological substrates remains to be determined by future studies. 相似文献
68.
69.
We report our experience of eight cases of isolated full thickness burns of the penis. Early excision of burns of the penile shaft and repair with a preputial flap or mesh split skin graft produces excellent results, with a reduction in complications and an early re-establishment of sexual function. Conservative treatment of burns of the glans, on the other hand, is appropriate and results in minimal scarring. 相似文献
70.