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   36448篇
  免费   2916篇
  国内免费   693篇
耳鼻咽喉   436篇
儿科学   2122篇
妇产科学   1301篇
基础医学   3488篇
口腔科学   430篇
临床医学   3531篇
内科学   5428篇
皮肤病学   392篇
神经病学   2708篇
特种医学   1312篇
外国民族医学   1篇
外科学   3145篇
综合类   3600篇
现状与发展   1篇
一般理论   5篇
预防医学   5842篇
眼科学   942篇
药学   2513篇
  13篇
中国医学   1061篇
肿瘤学   1786篇
  2024年   121篇
  2023年   724篇
  2022年   1445篇
  2021年   1833篇
  2020年   1498篇
  2019年   1627篇
  2018年   1466篇
  2017年   1413篇
  2016年   1299篇
  2015年   1200篇
  2014年   2317篇
  2013年   2809篇
  2012年   1846篇
  2011年   2064篇
  2010年   1656篇
  2009年   1602篇
  2008年   1711篇
  2007年   1680篇
  2006年   1342篇
  2005年   1262篇
  2004年   1040篇
  2003年   974篇
  2002年   787篇
  2001年   661篇
  2000年   525篇
  1999年   474篇
  1998年   444篇
  1997年   384篇
  1996年   315篇
  1995年   303篇
  1994年   287篇
  1993年   262篇
  1992年   232篇
  1991年   191篇
  1990年   188篇
  1989年   163篇
  1988年   147篇
  1987年   160篇
  1986年   149篇
  1985年   224篇
  1984年   201篇
  1983年   164篇
  1982年   149篇
  1981年   132篇
  1980年   123篇
  1979年   112篇
  1978年   83篇
  1977年   60篇
  1976年   49篇
  1975年   35篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
Although depression is associated to physical discomfort, meanings of the body in depression are rarely addressed in clinical research. Drawing on the concept of the lived body, this study explores depression as an embodied phenomenon. Using a hermeneutic phenomenological approach, the analysis of narrative‐based interviews with 11 depressed adults discloses a thematic structure of an embodied process of an ambiguous striving against fading. Five subthemes elicit different dimensions of this process, interpreted as disabling or enabling: feeling estranged, feeling confined, feeling burdensome, sensing life and seeking belongingness. In relation to clinical practice, we suggest that the interdisciplinary team can focus on enhancing the enabling dimensions, for example through guided physical activities to support the patient to feel more alive, capable and connected. Moreover, we suggest that the treatment process benefits from an increased awareness of the ambiguity in the patient's struggle, acknowledging both destructive and recharging elements of the withdrawing, and the perceived conflict in‐between.  相似文献   
2.
目的:对应用低分子肝素钙与奥扎格雷联合对患有脑血栓疾病的患者实施治疗的临床效果进行研究。方法整群选择在该院2012年12月—2014年12月就诊的患有脑血栓疾病的患者86例,随机分为对照组和治疗组,每组43例。采用奥扎格雷对对照组患者实施治疗;采用低分子肝素钙与奥扎格雷联合对治疗组患者实施治疗。对比神经功能缺损评分在药物治疗前后的变化幅度、脑神经功能恢复正常时间和脑血栓药物治疗计划实施总时间、脑血栓疾病药物治疗效果、用药期间的不良反应人数。结果治疗组患者神经功能缺损评分在药物治疗前后的变化幅度明显大于对照组;脑神经功能恢复正常时间(9.66±2.41)d和脑血栓药物治疗计划实施总时间(13.28±2.14)d明显短于对照组(13.62±3.47)、(17.39±3.20)d;脑血栓疾病药物治疗效果(总有效率90.6%)明显优于对照组(总有效率69.8%);用药期间的不良反应人数(1例)明显少于对照组(8例)。结论应用低分子肝素钙与奥扎格雷联合对患有脑血栓疾病的患者实施治疗的临床效果非常明显。  相似文献   
3.
This retrospective study aimed to evaluate radiation-induced pneumonitis (RIP) and a related condition that we define in this report—prolonged minimal RIP (pmRIP)—after stereotactic body radiotherapy (SBRT) for Stage I primary lung cancer in patients with chronic obstructive pulmonary disease (COPD). We assessed 136 Stage I lung cancer patients with COPD who underwent SBRT. Airflow limitation on spirometry was classified into four Global Initiative for Chronic Obstructive Lung Disease (GOLD) grades, with minor modifications: GOLD 1 (mild), GOLD 2 (moderate), GOLD 3 (severe) and GOLD 4 (very severe). On this basis, we defined two subgroups: COPD-free (COPD −) and COPD-positive (COPD +). There was no significant difference in overall survival or cause-specific–survival between these groups. Of the 136 patients, 44 (32%) had pmRIP. Multivariate analysis showed that COPD and the Brinkman index were statistically significant risk factors for the development of pmRIP. COPD and the Brinkman index were predictive factors for pmRIP, although our findings also indicate that SBRT can be tolerated in early lung cancer patients with COPD.  相似文献   
4.
5.
6.
7.
ObjectiveTo investigate the association between type 1 diabetes mellitus (T1D) and type 2 diabetes mellitus (T2D) with risk of sudden cardiac arrest (SCA).MethodsIn a prospective community-based study of SCA from February 1, 2002, through November 30, 2019, we ascertained 2771 cases age 18 years of age or older and matched them to 8313 controls based on geography, age, sex, and race/ethnicity. We used logistic regression to evaluate the independent association between diabetes, T1D, T2D, and SCA.ResultsPatients had a mean age of 64.5±15.9 years, were 33.3% female and 23.9% non-White race. Overall, 36.7% (n=1016) of cases and 23.8% (n=1981) of controls had diabetes. Among individuals with diabetes, the proportion of T1D was 6.5% (n=66) among cases and 2.0% among controls (n=40). Diabetes was associated with 1.5-times higher odds of SCA. Compared with those without diabetes, the odds ratio and 95% CI for SCA was 4.36 (95% CI, 2.81 to 6.75; P<.001) in T1D and 1.45 (95% CI, 1.30 to 1.63; P<.001) in T2D after multivariable adjustment. Among those with diabetes, the odds of having SCA were 2.41 times higher in T1D than in T2D (95% CI, 1.53 to 3.80; P<.001). Cases of SCA with T1D were more likely to have an unwitnessed arrest, less likely to receive resuscitation, and less likely to survive compared with those with T2D.ConclusionType 1 diabetes was more strongly associated with SCA compared with T2D and had less favorable outcomes following resuscitation. Diabetes type could influence the approach to risk stratification and prevention of SCA.  相似文献   
8.
Background/objectiveObstructive sleep apnea (OSA) is independently associated with dyslipidemia, a surrogate marker of atherosclerosis. Low-density lipoprotein (LDL)-cholesterol is accepted as a major independent risk factor for cardiovascular disease. However, non-high-density lipoprotein (HDL)-cholesterol is a better marker of atherogenic dyslipidemia and recommended as a target of lipid lowering therapy. We aimed to assess the prevalence of atherogenic dyslipidemia, and relationship between OSA severity and serum LDL-cholesterol and non-HDL cholesterol levels in OSA patients.MethodsWe retrospectively evaluated treatment naïve 2361 subjects admitted to the sleep laboratory of a university hospital for polysomnography. All subjects’ lipid profile including total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, and non-HDL-cholesterol were measured.ResultsOut of 2361 patients (mean age 49.6 ± 11.9 years; 68.9% male, apnea-hypopnea index 36.6 ± 28.4/h), 185 (7.8%) had no OSA and 2176 (92.2%) had OSA. Atherogenic dyslipidemia prevalence was high (57–66%) in OSA patients, and especially increased in severe OSA compared to other groups (p < 0.05). Though total and LDL-cholesterol did not differ between those with and without OSA, non-HDL-cholesterol (p = 0.020), and triglycerides (p = 0.001) were higher and HDL-cholesterol levels (p = 0.018) were lower in OSA patients than non-OSA. Non-HDL-cholesterol was significantly correlated with OSA severity (p < 0.001) and hypoxia parameters (p < 0.01), whereas LDL-cholesterol showed no correlation.ConclusionsAtherogenic dyslipidemia is highly prevalent and non-HDL-cholesterol levels are significantly increased, predominantly in severe OSA patients. Non-HDL-cholesterol but not LDL-cholesterol, is significantly correlated with OSA severity and hypoxia parameters. Therefore, it could be better to use non-HDL-cholesterol, which is a guideline recommended target of lipid therapy, as a marker of atherosclerotic cardiovascular risk in OSA patients.  相似文献   
9.
The purpose of this literature review is to investigate clinical treatment methods of total body irradiation within the context of a clinical department adopting a paediatric cohort with no existing technique. An extensive review of the literature was conducted using PubMed, Science Direct, Google Scholar, and Clinicians Knowledge Network. Articles were limited to nonhelical tomotherapy, nonparticle therapies, and those using hyperfractionated regimes. Total marrow irradiation was excluded because of national treatment and trial limitations. Of the numerous patient positioning methods present within the literature, the most comfortable and reproducible positioning methods for total body irradiation include both supine and the supine and/or prone combination. These positions increased stability and patient comfort during treatment, while also facilitating computed tomography data acquisition at the simulation stage. Ideally, dose calculations should be performed using a three-dimensional treatment planning system and quality assurance procedures that include in vivo dosimetry measurements. The available literature also suggests inhomogeneity correction factors and intensity modulation are superior to conventional open field techniques and should be implemented within developing protocols. Dynamic machine dose modulation is suggested to reduce department impact, removing the need for tissue compensators and accessory shielding devices, while providing significant improvements to treatment time and dose accuracy. Further long-term survival and intensity modulation studies are warranted, including direct comparisons of both dose modulation and treatment efficiency.  相似文献   
10.
The primary aim of this study was to evaluate the accuracy of sonographic estimation of fetal weight when performed at due date by first-line sonographers. This was a prospective study including 500 singleton pregnancies. Ultrasound examinations were performed by residents on delivery day. Estimated fetal weights (EFWs) were calculated and compared with the corresponding birth weights. The median absolute difference between EFW and birth weight was 200 g (100–330). This difference was within ±10% in 75.2% of the cases. The median absolute percentage error was 5.53% (2.70%–10.03%). Linear regression analysis revealed a good correlation between EFW and birth weight (r = 0.79, p < 0.0001). According to Bland–Altman analysis, bias was −85.06 g (95% limits of agreement: −663.33 to 494.21). In conclusion, EFWs calculated by residents were as accurate as those calculated by experienced sonographers. Nevertheless, predictive performance remains limited, with a low sensitivity in the diagnosis of macrosomia.  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