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   118249篇
  免费   11568篇
  国内免费   9021篇
耳鼻咽喉   992篇
儿科学   1098篇
妇产科学   1157篇
基础医学   13950篇
口腔科学   1959篇
临床医学   15968篇
内科学   17701篇
皮肤病学   1214篇
神经病学   6279篇
特种医学   4312篇
外国民族医学   78篇
外科学   12183篇
综合类   20942篇
现状与发展   40篇
一般理论   6篇
预防医学   7991篇
眼科学   3369篇
药学   12307篇
  96篇
中国医学   7321篇
肿瘤学   9875篇
  2024年   1468篇
  2023年   2049篇
  2022年   5035篇
  2021年   6413篇
  2020年   4914篇
  2019年   4080篇
  2018年   4204篇
  2017年   3749篇
  2016年   3605篇
  2015年   5448篇
  2014年   6662篇
  2013年   5854篇
  2012年   8533篇
  2011年   9408篇
  2010年   5927篇
  2009年   4677篇
  2008年   6045篇
  2007年   5985篇
  2006年   5793篇
  2005年   5864篇
  2004年   3810篇
  2003年   3491篇
  2002年   3005篇
  2001年   2662篇
  2000年   2808篇
  1999年   3000篇
  1998年   1998篇
  1997年   2017篇
  1996年   1550篇
  1995年   1472篇
  1994年   1270篇
  1993年   792篇
  1992年   987篇
  1991年   794篇
  1990年   666篇
  1989年   626篇
  1988年   520篇
  1987年   458篇
  1986年   399篇
  1985年   298篇
  1984年   137篇
  1983年   116篇
  1982年   68篇
  1981年   73篇
  1980年   47篇
  1979年   54篇
  1977年   2篇
  1974年   2篇
  1965年   2篇
  1963年   1篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.

Purpose

To evaluate the quality of life (QoL) and social support among family caregivers of a family member with a mental illness and to identify factors associated with the QoL.

Methods

This is a cross-sectional study, where participants were recruited and independently interviewed using a questionnaire, consisting of demographic characteristics, the Medical Outcome Survey SF-36 form, and social support rating scales. Multiple stepwise regression analysis was used to analyse the factors related to QoL.

Results

181 family caregivers were recruited in Shandong province, China. On a composite QoL score, family caregivers perceived that their QoL was poor (68.3), especially in the aspects of role-physical (61.3), role-emotional (57.6) and mental health (63.0). We also found family caregivers received low social support, especially in objective support and utilization of social support. Patient's illness state, care time, financial burden and objective support were significantly correlated to caregivers' QoL in the physical component score (PCS). Patient's illness state, patient's marital status, family monthly income, caregiver's knowledge about the illness, caregivers coordinating caring, life and work, subjective support received and utility of support were significantly associated with caregivers' QoL in the mental component score (MCS).

Conclusions

Social support had a significant correlation with caregivers' QoL. Caregivers should be encouraged to request assistance from other family members and friends in providing care, especially when caregivers are unemployed or long-time carers. Mental health education campaigns and helping families to maintain and enhance a supportive social network may provide useful means to improve caregivers' QoL.  相似文献   
2.
3.
Objective To analyze the pathological characteristics and prognostic factors of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). Methods A retrospective analysis of AAV patients with renal biopsy results admitted to Kidney Disease Center of the First Affiliated Hospital from January 2004 to February 2017 was performed. The patients were divided into 4 types according to Berden classification, and their clinical, pathological characteristics and prognosis were compared. The survival curves of each type of patients were plotted by Kaplan-Meier method, and the difference of survival curves was compared using Log-rank test. With entering the maintenance dialysis as the endpoint, Cox regression was used to analyze the prognostic factors. Results A total of 175 patients with AAV, including 59 cases (33.7%) of focal type, 39 cases (22.3%) of crescent type, 32 cases (18.3%) of sclerosis type, 45 cases (25.7%) of mixed type. The basal serum creatinine levels in crescent type group and sclerosis type group were significantly higher than those in the focal type group or mixed type group (all P<0.05), and loop necrosis rate in sclerosis type group was significantly lower than chat in the focal type group or crescent type group (both P<0.05). The median follow-up period was 11.8 (0.5-86.7) months. The event-free survival rates were 83.1%, 77.8%, 64.1% and 50.0% in the focal type, mixed type, crescent type and sclerotic type groups (Log-rank χ2=11.537, P=0.009). Cox regression analysis showed higher parathyroid hormone (HR=1.013, 95%CI 1.007-1.019, P<0.001), glomerular sclerosis ≥50% (HR=10.532, 95%CI 2.903-38.203, P<0.001) were independent risk factors for AAV patients entering maintenance dialysis, and higher estimated glomerular filtration rate (HR=0.943, 95%CI 0.896-0.993, P=0.025) was protective factor. Conclusion The prognosis of AAV renal damage is worsened according to focal, mixed, crescent and sclerosis types. Lower estimated glomerular filtration rate, higher parathyroid hormone and glomerular sclerosis ≥50% are independent risk factors for AAV patients entering maintenance dialysis.  相似文献   
4.
Axonal regeneration plays an important role in functional recovery after nervous system damage. However, after axonal injury in mammals, regeneration is often poor. The deletion of Krüppel-like factor-4 (Klf4) has been shown to promote axonal regeneration in retinal ganglion cells. However, the effects of Klf4 deletion on the corticospinal tract and peripheral nervous system are unknown. In this study, using a mouse model of sciatic nerve injury, we show that the expression of Klf4 in dorsal root ganglion sensory neurons was significantly reduced after peripheral axotomy, suggesting that the regeneration of the sciatic nerve is associated with Klf4. In vitro, dorsal root ganglion sensory neurons with Klf4 knockout exhibited significantly enhanced axonal regeneration. Furthermore, the regeneration of the sciatic nerve was enhanced in vivo following Klf4 knockout. Finally, AAV-Cre virus was used to knockout the Klf4 gene in the cortex. The deletion of Klf4 enhanced regeneration of the corticospinal tract in mice with spinal cord injury. Together, our findings suggest that regulating KLF4 activity in neurons is a potential strategy for promoting axonal regeneration and functional recovery after nervous system injury. This study was approved by the Animal Ethics Committee at Soochow University, China (approval No. SUDA20200316A01).

Chinese Library Classification No.R456; R741; Q344+.14  相似文献   
5.
目的总结分析胃癌D2根治术后发生大出血的原因及治疗方法并探讨其对生存预后的影响。方法回顾性分析广东省中医院2012年1月至2016年3月258例行胃癌D2根治术患者的临床资料,根据术后是否发生大出血分为出血组和非出血组。结果14例患者(5.4%)术后发生大出血;吻合口出血、十二指肠残端瘘或破裂是出血的主要原因;二次手术和胃镜止血是主要治疗措施。两组的短期总生存期有统计学意义(1年:P=0.017,3年:P=0.011)。结论吻合口出血、十二指肠残端瘘或破裂是胃癌D2根治术后出血的主要原因,及时诊断和治疗能有效降低病死率。胃癌D2根治术后大出血会降低患者的短期总生存期。  相似文献   
6.
Objective To investigate the predictive value of nutritional and fluid status measured by bioelectrical impedance methods for the prognosis of acute kidney injury (AKI) patients undergoing continuous renal replacement therapy (CRRT). Methods Patients with severe AKI received CRRT in the First Affiliated Hospital of Nanjing Medical University from September 2016 to September 2018 were enrolled, and divided into death group and survival group according to 28-day survival. Cox regression was used to analyze the association between 28-day survival and lean tissue index (LTI), fat tissue index (FTI), the ratio of extracellular water (ECW) and body cell mass (BCM) (ECW/BCM), and overhydration (OH), respectively. Results A total of 156 patients were included, including 101 males and 55 females. The age was (62.7±15.4) years, with sequential organ failure assessment (SOFA) score of 9.9±3.9. The 28-day mortality rate was 46.2%. The pre-CRRT OH values in the 28-day survival group and death group were 2.95(1.80, 5.50) L and 4.20(2.95, 5.70) L(P=0.016), and ECW/BCM values were 1.00(0.76, 1.18) and 1.07(0.88, 1.25) (P=0.033), respectively. Univariate Cox regression analysis showed that pre-CRRT high OH values (HR=1.08, 95%CI 1.00-1.17, P=0.040) and high ECW/BCM values (HR=3.02, 95%CI 1.46-6.22, P=0.003) were associated with 28-day death. The changes of OH values (HR=0.83, 95%CI 0.72-0.95, P=0.008) and ECW/BCM values (HR=6.79, 95%CI 1.72-26.82, P=0.006) between pre-CRRT and the 7th day after CRRT initiation were significantly associated with 28-day mortality in patients who survived 7 days after CRRT initiation. After adjusting for age, gender, and SOFA scores, multivariate Cox regression analysis showed that the high OH value (HR=1.16, 95%CI 1.06-1.27, P=0.002) and the high ECW/BCM value (HR=2.80, 95%CI 1.30-6.06, P=0.003) before CRRT, the change of OH value (HR=0.82, 95%CI 0.72-0.95, P=0.008) and ECW/BCM value (HR=2.79, 95%CI 1.30-5.98, P=0.009) between the 7th day after CRRT initiation and pre-CRRT, were independently associated with 28-day death, while LTI (HR=0.93, 95%CI 0.86-1.02, P=0.113) and FTI (HR=0.98, 95%CI 0.92-1.04, P=0.475) before CRRT were uncorrelated with 28-day death. Conclusions In bioelectrical impedance analysis, the high OH value and high ECW/BCM value before CRRT are associated with 28-day mortality in patients with AKI, while the nutritional indicators LTI and FTI before CRRT are not significantly related. The correction of fluid overload by CRRT within 7 days may reduce the risk of 28-day mortality.  相似文献   
7.
8.
目的探讨腹腔镜内环结扎术治疗儿童复发性腹股沟斜疝的优势及手术经验。 方法选择2013年1月至2018年1月,广州市妇女儿童医疗中心收治的34例复发性腹股沟斜疝患儿为研究对象。回顾性分析其临床病例资料。根据本次入院采取的手术治疗方式,将其分为腹腔镜组(n=19,采用腹腔镜内环结扎术)和开放手术组(n=15,采用疝囊高位结扎术)。采用独立样本t检验及χ2检验,对2组患儿一般临床资料、术中及术后情况等,进行统计学分析。本研究符合2013年修订的《世界医学协会赫尔辛基宣言》要求,所有患儿监护人均于术前签署手术治疗知情同意书。 结果①开放手术组患儿术后,3例出现阴囊血肿,1例出现医源性隐睾。2组患儿术后均未发生伤口感染、睾丸萎缩、阴囊积液及再次复发等其他并发症。②2组患儿中,男性患儿所占比例、月龄及初次手术为腹腔镜手术所占比例比较,差异均无统计学意义(P>0.05)。腹腔镜组患儿的手术时间、术中出血量、住院时间及术后并发症发生率分别为(30.0±10.7) min、(1.0±0.3) mL、(1.2±0.4) d、0,均显著短于或少于开放手术组的(44.7±24.5) min、(2.3±1.3) mL、(3.3±1.0) d、26.7%;其住院费用为(7 547±820)元,则显著高于开放手术组的(5 488±1 218)元,并且差异均有统计学意义(t=-2.347、P=0.044,t=-3.859、P=0.002,t=-8.171、P<0.001,P=0.029,t=5.580、P<0.001)。 结论腹腔镜内环结扎术治疗儿童复发性腹股沟斜疝,具有安全有效、术中情况良好、术后并发症少等优势,但住院费用相对偏高。  相似文献   
9.
目的分析乙型肝炎(乙肝)病毒(Hepatitis B virus,HBV)高载量孕妇孕期HBV脱氧核糖核酸(HBV desoxyribonucleic acid,HBV-DNA)水平和HBVe抗原(HBV e antigen,HBeAg)阳性率以及孕期抗病毒治疗结合标准阻断措施对其所生婴儿母婴传播阻断失败率的影响。方法通过医院信息系统收集HBV-DNA高载量(≥2×10^6IU/mL)孕妇血清学检测结果、抗病毒药物使用等信息,描述HBV-DNA载量和HBeAg阳性率;对HBV-DNA高载量孕妇所生婴儿进行乙肝疫苗(Hepatitis B vaccine,HepB)和乙肝免疫球蛋白(Hepatitis B immunoglobulin,HBIG)联合免疫,在完成第3剂HepB后7月龄-2岁对乙肝表面抗原和HBV-DNA进行随访检测,分析母婴传播阻断失败率。结果共纳入1822名HBV-DNA高载量孕妇,接受、未接受抗病毒治疗分别占75.19%、24.81%。孕妇妊娠期、分娩前HBV-DNA≥1.0×10^8IU/mL比例分别为68.10%(933/1370)、0.15%(2/1370)(χ^2=2692.27,P<0.0001)。接受抗病毒治疗组妊娠期、分娩前HBeAg阳性率分别为96.53%(1001/1037)、96.16%(1251/1301)(χ^2=0.23,P=0.635),未接受抗病毒治疗组妊娠期、分娩前HBeAg阳性率分别为97.70%(298/305)、96.98%(417/430)(χ^2=0.36,P=0.550)。两组HepB和HBIG联合免疫后母婴传播阻断失败率分别为0.42%(3/714)、6.67%(14/210)(χ^2=31.69,P<0.0001)。结论孕妇HBV-DNA高载量以≥1.0×10^8IU/mL为主,孕期抗病毒治疗可显著降低孕妇HBV-DNA载量,结合HepB和HBIG联合免疫可显著降低其所生婴儿HBV母婴传播阻断失败率。  相似文献   
10.
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