首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2195篇
  免费   67篇
  国内免费   44篇
耳鼻咽喉   18篇
儿科学   30篇
妇产科学   44篇
基础医学   326篇
口腔科学   33篇
临床医学   126篇
内科学   411篇
皮肤病学   24篇
神经病学   272篇
特种医学   116篇
外科学   210篇
综合类   4篇
预防医学   248篇
眼科学   69篇
药学   207篇
中国医学   4篇
肿瘤学   164篇
  2023年   11篇
  2022年   20篇
  2021年   38篇
  2020年   23篇
  2019年   22篇
  2018年   35篇
  2017年   20篇
  2016年   34篇
  2015年   41篇
  2014年   63篇
  2013年   64篇
  2012年   150篇
  2011年   161篇
  2010年   87篇
  2009年   77篇
  2008年   140篇
  2007年   168篇
  2006年   153篇
  2005年   168篇
  2004年   158篇
  2003年   118篇
  2002年   140篇
  2001年   27篇
  2000年   24篇
  1999年   13篇
  1998年   46篇
  1997年   22篇
  1996年   30篇
  1995年   8篇
  1994年   17篇
  1993年   15篇
  1992年   10篇
  1991年   14篇
  1990年   10篇
  1989年   10篇
  1988年   10篇
  1987年   9篇
  1986年   9篇
  1985年   11篇
  1984年   9篇
  1983年   13篇
  1982年   8篇
  1980年   6篇
  1979年   9篇
  1978年   11篇
  1977年   6篇
  1976年   13篇
  1975年   12篇
  1974年   5篇
  1973年   6篇
排序方式: 共有2306条查询结果,搜索用时 15 毫秒
21.
OBJECTIVE: To study the possible association between orofacial herpes during pregnancy and pregnancy complications including preterm birth and low birth weight, since the results of previous studies are inconsistent. METHOD: The population-based large data set of the Hungarian Case-Control Surveillance System of Congenital Abnormalities was used; pregnancies in mothers with and without recurrent orofacial herpes were compared. RESULTS. Of 38,151 newborn infants, 572 (1.5%) had mothers with recurrent orofacial herpes during pregnancy, while 37 577 had mothers with no orofacial herpes. Pregnant women with recurrent orofacial herpes had a higher prevalence of severe nausea and vomiting, threatened preterm delivery, and placental disorders but a lower prevalence of preeclampsia. Mothers with recurrent orofacial herpes during pregnancy also had a somewhat longer (0.4 weeks) gestation (adjusted t = 2.7; p = 0.006) and an obviously lower proportion of preterm births (3.5% vs. 9.3%; adjusted POR with 95% CI = 0.42, 0.27-0.65). However, there was no significant difference in the mean birth weight and rate of low birth weight infants between the two study groups. CONCLUSION: Recurrent orofacial herpes during pregnancy is associated with a smaller proportion of preterm births.  相似文献   
22.
23.
24.
Although excessive alcohol consumption is by far the most frequent cause of recurrent acute pancreatitis (AP) cases, specific therapy is still not well established to prevent recurrence. Generally, psychological therapy (e.g., brief intervention (BI)) is the cornerstone of cessation programs; however, it is not yet widely used in everyday practice. We conducted a post-hoc analysis of a prospectively collected database. Patients suffering from alcohol-induced AP between 2016 and 2021 received 30 min BI by a physician. Patient-reported alcohol consumption, serum gamma-glutamyl-transferase (GGT) level, and mean corpuscular volume (MCV) of red blood cells were collected on admission and at the 1-month follow-up visit to monitor patients’ drinking habits. Ninety-nine patients with alcohol-induced AP were enrolled in the study (mean age: 50 ± 11, 89% male). A significant decrease was detected both in mean GGT value (294 ± 251 U/L vs. 103 ± 113 U/L, p < 0.001) and in MCV level (93.7 ± 5.3 U/L vs. 92.1 ± 5.1 U/L, p < 0.001) in patients with elevated on-admission GGT levels. Notably, 79% of the patients (78/99) reported alcohol abstinence at the 1-month control visit. Brief intervention is an effective tool to reduce alcohol consumption and to prevent recurrent AP. Longitudinal randomized clinical studies are needed to identify the adequate structure and frequency of BIs in alcohol-induced AP.  相似文献   
25.
Major advances have been made in the identification and prevention of perinatal factors that lead to long-term handicap or neurologic deficits. When the infant or child exhibits a major handicap, scrutiny of the pregnancy management often occurs in an attempt to define the causal factors. The medical goal of this inquiry is to prevent injuries and, when possible, to eliminate these factors. In the litigious sense, any deviation from optimal, ideal care or any unusual observations, such as unusual or atypical fetal heart rate patterns, are often causally linked to the adverse outcome. There are at least four categories of major fetal injury that probably occur prior to labor. An awareness of, and a diligent search for, details will no doubt clarify the legitimate origins of many so-called birth injuries. Hence the common tendency to fixate on minor deviations and/or deficiencies of labor and delivery management as causing catastrophic injuries will be successfully challenged.  相似文献   
26.
Recently, it has been suggested, that differentiated cells are more resistant to the apoptotic effect of DNA damaging agents possibly due to the decreased activity of “damage detecting/apoptosis triggering” mechanism. Previously, we have shown, that PMA pretreatment reduced etoposide-(ETO) but enhanced staurosporine- (STA) -induced apoptosis in HT58 cells. Data presented here show that the HT58 human, “mature” B-lymphoma cells exposed to PMA secrete more IgM into the supernatant indicating commitment of cells to perform differentiated function. The sensitivity of HT58 cells to ETO- or STA-induced apoptosis is influenced diversely with PMA pre- or posttreatment. Interestingly, the DNA damage (gamma radiation, bleomycin, ETO) or okadaic acic (30 nM) reduced the [PMA+STA] - induced apoptosis.  相似文献   
27.
After congenital heart defects neural tube defects (NTDs) is the second most prevalent congenital malformation among birth defects. The average rate of isolated NTDs is 1.4-2.0 per 1000 live births worldwide. The etiology of isolated (nonsyndromic) NTDs is believed to be the result of a combination of genetic predisposition and environmental factors. Over 80 genes believed to be engaged in the neurulations have been identified during the investigation and research of the mouse models. Despite exhaustive research efforts, now spanning several decades, little is known about the actual genetic mechanisms governing the primary events involved in neural tube closure (NTC).  相似文献   
28.
29.
30.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号