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   29502篇
  免费   2817篇
  国内免费   374篇
耳鼻咽喉   576篇
儿科学   5186篇
妇产科学   996篇
基础医学   1179篇
口腔科学   198篇
临床医学   2541篇
内科学   5299篇
皮肤病学   210篇
神经病学   2017篇
特种医学   512篇
外国民族医学   1篇
外科学   3559篇
综合类   2187篇
一般理论   1篇
预防医学   5149篇
眼科学   160篇
药学   1168篇
中国医学   160篇
肿瘤学   1594篇
  2024年   34篇
  2023年   672篇
  2022年   933篇
  2021年   1772篇
  2020年   1391篇
  2019年   1341篇
  2018年   1285篇
  2017年   1196篇
  2016年   1308篇
  2015年   1212篇
  2014年   1995篇
  2013年   2339篇
  2012年   1527篇
  2011年   1741篇
  2010年   1325篇
  2009年   1433篇
  2008年   1493篇
  2007年   1399篇
  2006年   1192篇
  2005年   1024篇
  2004年   881篇
  2003年   686篇
  2002年   590篇
  2001年   537篇
  2000年   422篇
  1999年   336篇
  1998年   313篇
  1997年   253篇
  1996年   218篇
  1995年   205篇
  1994年   175篇
  1993年   181篇
  1992年   156篇
  1991年   119篇
  1990年   100篇
  1989年   97篇
  1988年   120篇
  1987年   85篇
  1986年   109篇
  1985年   104篇
  1984年   81篇
  1983年   47篇
  1982年   40篇
  1981年   38篇
  1980年   28篇
  1979年   41篇
  1978年   24篇
  1976年   23篇
  1975年   17篇
  1974年   19篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
对218例女性乳癌术后进行了十年以上的随访观察。随访率为95.87%。术后总的十年生存率为54.87%。Ⅰ期为85.71%,Ⅱ期为53.09%。Ⅲ期为30.76%。阐明了术后疗效与妊娠哺乳,肿瘤部位,肿瘤大小,临床期别,淋巴结转移情况及病理类型有明显关系。讨论了手术方式对术后的影响,提示扩大根治术对Ⅰ、Ⅱ期乳癌并无明显优越性。  相似文献   
42.
We followed all consecutive hip fracture patients admitted between 2004 and 2006, identified cases in which the intention was to treat non-operative and compared their functional outcome and mortality with a similar cohort treated surgically over the same period. We recorded length of hospital stay, place of discharge, pre and post-fracture mobility and residence, 30 days and 1 year mortality, re-admission due to same fracture and delayed surgery. The group treated surgically was recruited and matched for age, gender, pre and post-fracture mobility, mental confusion and independence. 25 patients were treated non-operative. 22 patients treated surgically over the same time period matched the patient characteristics of the non-operative arm. The mean hospital stay was 13 days in both groups. There were 4 extra-capsular fractures (3 displaced) and 21 intra-capsular fractures (5 displaced) in the non-operative arm and 11 extra-capsular fractures and 9 intra-capsular fractures in the surgically treated arm. 4 patients from the non-operative treatment group underwent late surgery because of persisting hip pain 20 days-2 months after the index event (2 cannulated screws, 1 hemiarthroplasty, 1 total hip arthroplasty). 11 patients in the surgical treatment arm underwent dynamic screw fixation, 1 had cannulated screw, 1 had total hip replacement and 7 had hemiarthroplasty. 14 of the non-operative treated patients were mobile independently or with aid before fracture but only 9 patients retained their pre-fracture mobility following treatment, compared to 16 patients pre-fracture and 11 patients post-fracture after surgery. 16 patients treated non-operative were living independently prior to injury but only 7 went back to their own residence. Of the operatively treated patients 14 patients were living independently and 10 patients went back to their previous residence. 1 month and 1 year mortality in the non-operative treated group was 4/21 and 7/21 respectively compared to 1/20 and 5/20 in the operative fixation group. There was no statistically significant difference in mobility, residence or mortality between the two groups (Fisher exact test, p > 0.05). Non-operative management after hip fracture is suitable for medically unfit patients and does not result in statistically significant difference in functional outcome or mortality compared to patients treated surgically.  相似文献   
43.
Background and objective  The purpose of this study is to assess whether Chinese children with high apnea–hypopnea index (AHI) are sleepier by a modified Epworth Sleepiness Scale (ESS). Materials and methods  Records were retrospectively reviewed. We included children who were between 3 and 12 years old, admitted for overnight polysomnogram because of suspected obstructive sleep apnea syndrome (OSAS). A modified ESS was used to assess excessive daytime sleepiness (EDS) of the children. Results  One hundred ninety-two Chinese children were included. Children with high AHI, defined as AHI > 5.0, were sleepier than children with AHI less than or equal to 5. After adjustment by age, gender, and obesity, children with high AHI remained significantly sleepier. Modified ESS was significantly correlated with AHI (rho = 0.124, 95% CI = 0.004–0.281). Modified ESS score of >8 was the best cutoff point with the sensitivity and specificity of 0.29 and 0.91, respectively. The odds ratio of children with modified ESS > 10 having high AHI was 4.231 (95%CI = 1.248 to 14.338) and children with modified ESS > 8 had the highest odds ratio, 4.295(95%CI = 1.66 to 11.1), of having high AHI. Conclusion   Chinese children with high AHI appear to be sleepier than children with low AHI. Children with suspected OSAS and high modified ESS, i.e., ESS > 8, had significantly higher odds ratio of having high AHI. Increased sleepiness is a specific but not a sensitive symptom in snoring children with high AHI. Screening for EDS in snoring children may help us identify those with high AHI and prioritize the management of those children. All authors worked and the study was carried out in Kwong Wah Hospital in Hong Kong. There was no conflict of interest and no specific source of funding for the study.  相似文献   
44.
45.
目的 评价准分子激光原位角膜磨镶术(excimer laser in situ keratomileusis,LASIK)治疗儿童远视性屈光参差的疗效.方法 使用美国Summit公司的SVS Apex plus准分子激光系统及Moria公司的微型板层角膜切割系统(LSK),对8例9~14岁远视性屈光参差患者进行LASIK手术,术后进行双眼视训练和系统的弱视治疗.结果 术后裸眼视力和矫正视力明显提高,术前平均最佳矫正视力0.23,术后6个月平均最佳矫正视力0.65;屈光度明显降低,但平均仍残留 2.81D;8例患者全部建立同时视和融合功能,6例有立体视功能.结论 LASIK治疗儿童远视性屈光参差安全有效,可明显提高视力,恢复和建立双眼视功能.  相似文献   
46.
7 小儿胆石症的诊断与治疗   总被引:2,自引:0,他引:2       下载免费PDF全文
目的探讨小儿胆石症的病因、诊断及治疗方法。方法分析22例小儿胆石症的临床资料,20例行手术治疗,2例行非手术治疗。14例行胆囊切除术(其中8例行腹腔镜胆囊切除术),3例行胆总管切开取石、T管引流术,2例行胆囊切除、胆总管探查、T管引流术,1例行胆总管囊肿切除、肝总管空肠Roux-en-Y吻合术。结果18例经手术治疗后症状消失,术后1例出现胆瘘,经引流后痊愈,1例右肝管内结石残留。18例(81.8%)得到随访,4例失访。随访5个月至7年,患儿生长发育正常,3例偶有腹痛、腹胀,1例行二次胆总管切开取石术,术后恢复顺利。行非手术治疗的2例病人经保守治疗后近期症状缓解,其中1例症状反复发作。结论对有腹痛者首选B超检查,对有胆总管扩张或黄疸的患儿结合CT检查可提高正确诊断率;症状明显的胆石症应早期手术治疗;腹腔镜可作为胆囊切除的首选治疗方法。  相似文献   
47.
儿童无症状尿检异常IgA肾病的临床病理和预后分析   总被引:2,自引:0,他引:2  
目的 探讨儿童无症状尿检异常的IgA肾病的临床病理特征和预后。 方法 对54例IgA肾病儿童的临床和病理特征进行分析。根据起病时有无临床症状分为无症状尿检异常组和有症状肾炎组。组织病理学分级参照Lee氏和Katafuchi氏半定量积分法。 结果 无症状尿检异常组18例,有症状肾炎组36例。有症状肾炎组尿蛋白量(24 h)明显高于无症状尿检异常组[(2.3±2.2) g比(0.4±0.3) g,P < 0.05]。无症状尿检异常的IgA肾病儿童表现为镜下血尿者,87%有尿微量白蛋白增高。无症状尿检异常IgA肾病患儿病理表现以Lee 氏Ⅰ~Ⅱ级为主,2例表现为Lee氏Ⅳ~Ⅴ级和 5例发生Katafuchi Ⅱ~Ⅲ级肾小管间质病变。有症状肾炎组Lee氏病理分级以Ⅱ~Ⅲ级为主,两者病理分级分布差异无统计学意义(P > 0.05)。全组患儿平均随访(26.9±8.8)月后,1例病理为Lee 氏Ⅴ级患儿进入终末期肾衰竭,其余患儿Scr均无升高1倍以上。 结论 无症状尿检异常的儿童IgA肾病虽临床症状轻微,但可出现病理损害严重的病例,并影响其预后。  相似文献   
48.
BACKGROUND: Dialysis patient mortality remains high, and this high mortality may be due to many factors. In peritoneal dialysis (PD) patients, old age, co-morbid diseases, malnutrition, low residual renal function (RRF) and a high peritoneal transport rate have been shown to influence survival, but the relative importance of these factors may differ between different patient populations. Besides, centre practice patterns may differ between centres and may influence patient survival. In addition, the literature suggests that dialysis patient survival may be better in Asian than in Caucasian patients. METHODS: The influence of centre and patient characteristics on patient survival was investigated in 132 Korean and 106 Swedish incident PD patients, who underwent initial biochemical measurements and assessment of adequacy of dialysis, nutritional status, RRF and peritoneal transport characteristics. RESULTS: At the start of PD, Korean patients had a higher prevalence of diabetes, peritoneal Kt/V(urea), peritoneal creatinine clearance and peritoneal fluid removal, and lower body mass index, RRF and dialysate to plasma creatinine concentration ratio (D/P Cr) compared with Swedish patients. Significantly more patients from Korea were placed on temporary haemodialysis before PD (100 out of 132) when compared with Swedish patients (21 out of 106). During the follow-up, there was a significantly higher rate of transfer to other units in Korea and a significantly higher rate of kidney transplantation in Sweden. On Kaplan-Meier analysis, overall patient survival did not differ and relative risk for death was also not different between the two centres even after adjustment for age, diabetes, cardiovascular disease, RRF and D/P Cr. On Cox proportional hazards multivariate analysis, age, diabetes, RRF and D/P Cr were found to be independent predictors of mortality in the combined cohort of patients. While age, diabetes and D/P Cr were independent predictors of mortality in Korean patients, age and RRF independently predicted mortality in Swedish patients. CONCLUSION: Although there were significant differences in centre and patient characteristics, we were unable to confirm a survival advantage for Korean over Swedish PD patients. The results of this study suggest that the reported difference in survival between Asian and Caucasian dialysis patients may have been due, in part, to differences in centre and patient characteristics rather than to race as such. The genetic influence on patient characteristics remains, however, to be elucidated.  相似文献   
49.
围产儿死亡545例原因分析   总被引:3,自引:0,他引:3  
目的 探讨围产儿死亡原因,以提高围产期保健工作质量及降低围产儿死亡率。方法 对我院12年来围产儿死亡病历进行回顾性分析。结果 12年间围产儿死亡95例,占16.88‰,死胎64.84%,死产26.37%,新生儿死亡8.79%。围产儿死亡原因依次为早产、胎儿畸形、缺氧综合征、脐带因素、胎位异常、胎盘因素及妊娠并发症。新生儿死亡主要因早产、呼吸窘迫综合症(RDS)所致。结论 加强围产期监护,预防为主,提高产科质量,达到降低围产儿死亡率。  相似文献   
50.
There is limited information on the relationship between parental practices that specifically discourage current cigarette smoking and adolescent cessation, and how this relationship varies by age. Among 1629 adolescent smokers, self-reported receipt of parental communication not to smoke was significantly and positively associated with readiness to quit. The strength and significance of this association decreased from early to middle adolescence and was not significant in late adolescence.  相似文献   
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