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   2219篇
  免费   116篇
  国内免费   2篇
耳鼻咽喉   29篇
儿科学   159篇
妇产科学   64篇
基础医学   232篇
口腔科学   38篇
临床医学   194篇
内科学   318篇
皮肤病学   55篇
神经病学   158篇
特种医学   49篇
外科学   251篇
综合类   93篇
预防医学   113篇
眼科学   40篇
药学   279篇
中国医学   17篇
肿瘤学   248篇
  2023年   11篇
  2022年   37篇
  2021年   96篇
  2020年   39篇
  2019年   57篇
  2018年   61篇
  2017年   46篇
  2016年   72篇
  2015年   72篇
  2014年   90篇
  2013年   98篇
  2012年   130篇
  2011年   159篇
  2010年   73篇
  2009年   57篇
  2008年   91篇
  2007年   82篇
  2006年   84篇
  2005年   72篇
  2004年   81篇
  2003年   60篇
  2002年   58篇
  2001年   41篇
  2000年   47篇
  1999年   46篇
  1998年   18篇
  1996年   14篇
  1995年   10篇
  1994年   15篇
  1992年   29篇
  1991年   18篇
  1990年   31篇
  1989年   30篇
  1988年   35篇
  1987年   30篇
  1986年   32篇
  1985年   30篇
  1984年   25篇
  1983年   27篇
  1979年   24篇
  1977年   13篇
  1976年   9篇
  1974年   22篇
  1973年   9篇
  1972年   16篇
  1971年   17篇
  1970年   12篇
  1969年   11篇
  1968年   16篇
  1967年   15篇
排序方式: 共有2337条查询结果,搜索用时 15 毫秒
71.
72.
J Clin Hypertens (Greenwich). 2012;14:78–84. ©2012 Wiley Periodicals, Inc.The Observational Study on Cognitive Function and SBP Reduction (OSCAR) provided opportunities to examine the influence of eprosartan on trends in cognitive performance in a large population of patients with difficult‐to‐treat hypertension (DTTH). A total of 4649 patients diagnosed retrospectively with DTTH, defined as systolic/diastolic blood pressure (SBP/DBP) ≥140/90 mm Hg despite use of at least 3 antihypertensive drugs during the month preceding the baseline visit comprised the intention‐to‐treat (ITT) cohort. The patients were given eprosartan‐based antihypertension therapy (EBT; 600 mg/d). Blood pressure and cognitive function parameters included significant (P<.001) differences for DTTH vs non‐DTTH patients such as older age, body mass index, SBP and pulse pressure (PP), and lower Mini‐Mental State Examination (MMSE) score. After EBT for 6 months, SBP/DBP in DTTH was 138.8±12.2/81.9±7.4 (ΔSBP−26±15.7; ΔDBP−11.4±9.8); PP was 57.0±10.8 (ΔPP−14.5±13.8) (all P<.001 vs baseline and non‐DTTH group). A total of 2576 patients (87.4%) responded to EBT (ie, SBP <140 mm Hg and/or ΔSBP ≥15 mm Hg, or DBP <90 mm Hg and/or ΔDBP ≥10 mm Hg); 1426 DTTH patients (48.4%) achieved normalized SBP/DBP (ie, SBP <140 mm Hg and DBP <90 mm Hg). ΔPP in DTTH‐isolated systolic hypertension (ISH) was −18.0±13.3 mm Hg (P=.003 vs DTTH‐systolic‐diastolic hypertension). End‐of‐EBT mean MMSE was 27.5±3.0 (P<.001 vs baseline). Blood pressure responses after EBT coincided with stabilization/improvement of MMSE in this retrospective investigation in DTTH patients. The average improvement in MMSE in DTTH patients was similar to that in non‐DTTH patients. EBT effects on PP may be relevant to the evolution of MMSE in DTTH‐ISH patients.

The Observational Study on Cognitive Function and SBP Reduction (OSCAR) was designed to examine the safety and tolerability of once‐daily therapy with eprosartan in a very large community‐dwelling population of patients with arterial hypertension recruited in 28 countries and managed in routine primary care. This study provided opportunities to examine the influence of the angiotensin receptor blocker (ARB) eprosartan on trends in cognitive performance in a large population of patients with high blood pressure (BP).The principal findings of OSCAR have been reported previously. 1 A 6‐month period of antihypertensive therapy based on eprosartan was associated with a significant reduction in mean systolic BP (SBP) and a significant improvement in mean Mini‐Mental State Examination (MMSE) score (P<.0001 for both outcomes). In multiple linear regression, cognitive decline was demonstrated to be independently and inversely correlated with SBP reduction (odds ratio, 0.77; 95% confidence interval [CI], 0.73–0.82).The intention‐to‐treat (ITT) cohort of OSCAR comprised 25,745 adult patients with hypertension. This large number of patients enabled us to identify several large subgroups for further investigation, with the intention of adding to what are still sometimes limited epidemiologic data on specific types of patients.Recent revisions to extant European hypertension guidelines and first reports of new treatment options for this condition 2 , 3 , 4 are indications that resistant hypertension is a pressing clinical priority. Poorly controlled high BP may be a factor in cognitive decline in older patients. Observations from several thousand patients in a real‐world survey may be instructive for the better management of this condition. Accordingly, we report here our findings in a retrospectively identified cohort of almost 3000 patients from the OSCAR population classified as having difficult‐to‐treat hypertension (DTTH) at baseline.  相似文献   
73.
Purpose

To describe the demographics, clinical features, and treatment outcomes with systemic steroids in eyes presenting with post-fever retinitis (PFR) from Central India.

Methods

Single-center, retrospective analysis of 147 eyes of 98 PFR cases between 2011 and 2019.

Results

Mean age of the study cohort was 33.46?±?12.76 years, with 72 males and 26 females. The mean interval between the onset of fever and the diminution of vision was 21.10?±?13.54 days (range 0–60 days). The number of PFR cases increased over the nine years with 89 cases (90.1%) presenting during winters. Unilateral involvement was seen in 49 cases, while 49 had bilateral involvement. Clinical characteristics included: multifocal retinitis (n?=?122; 61.2%), hemorrhages (n?=?132; 89.8%), disc edema (n?=?57; 38.8%), anterior chamber reaction (n?=?28; 19%), and vitritis (n?=?103; 70.1%). Treatment included intravenous followed by oral steroids in 70 patients and oral steroids exclusively in 23; five patients denied treatment. The visual acuity improved from 1.09?±?0.52 LogMAR to 0.29?±?0.42 LogMAR (p?<?0.05).

Conclusion

There has been an increase in the prevalence of PFR cases over the last decade with clustering during the winters. Multifocal retinitis, retinal hemorrhages, and vitritis were the most common clinical findings in our series. The retinitis resolved with improvement in vision following steroid therapy in all eyes.

  相似文献   
74.
Breast carcinoma is the most common cause of carcinoma death in women. Sometimes, difficulty arises to differentiate between premalignant lesions and carcinoma by routine histopathology. Our study was done to establish the role of morphometry and immunohistochemistry to solve this problem. In this study, total 60 cases of different breast lesions were included and 10 controls were also included to compare the results with the normal findings. They were studied by hematoxylin and eosin-stained sections for morphometry and routine histological study; as well as by proliferative markers such as proliferating cell nuclear antigen and p53. Invasiveness was studied using immunohistochemical staining with 34 βE12 monoclonal antibody. Statistically significant differences were found in morphometric parameters and in expression of proliferative markers between most of them. Morphometry and immunohistochemistry help in the proper diagnosis of different breast lesions that lie in the gray zone on routine histopathology.  相似文献   
75.
76.
77.
Energy Failure     
Energy failure from mitochondrial dysfunction is proposed to be a central mechanism leading to neuronal death in a range of neurodegenerative diseases. However, energy failure has never been directly demonstrated in affected neurons in these diseases, nor has it been proved to produce degeneration in disease models. Therefore, despite considerable indirect evidence, it is not known whether energy failure truly occurs in susceptible neurons, and whether this failure is responsible for their death. This limited understanding results primarily from a lack of sensitivity and resolution of available tools and assays and the inherent limitations of in vitro model systems. Major advances in these methodologies and approaches should greatly enhance our understanding of the relationship between energy failure, neuronal dysfunction, and death, and help us to determine whether boosting bioenergetic function would be an effective therapeutic approach. Here we review the current evidence that energy failure occurs in and contributes to neurodegenerative disease, and consider new approaches that may allow us to better address this central issue. Ann Neurol 2013;74:506–516  相似文献   
78.
There is an increasing awareness for recognition of sleep disorders in India; however, there is still a huge gap in the number of people suffering from various sleep disorders, in the community versus those visiting hospital clinics for the same. Ours is a neurology services-based sleep disorders clinic, which has evolved successfully over the last decade. In this study, we aimed to evaluate the changes in referral patterns and distribution of various sleep disorders in the patients presenting to the clinic.

Materials and Methods:

This is a retrospective chart review-based study on all patients seen over an 8-year period, divided into 2 groups comprising of patients seen during the first 4 years versus those seen over the next 4 years. Only those patients who had the sleep disorder as their presenting manifestation and those who had been formally interviewed with a pre-structured questionnaire detailing about the main features of the common sleep disorders according to the ICSD-R were included. Patients, in whom the sleep disorder could be clearly attributable to another neurological or systemic disorder, were excluded. Statistical analysis was carried out to identify the differences between the two groups as regards the distribution of various sleep disorders and other clinical data.

Results:

Among 710 patients registered in the clinic, 469 were included for analysis and 222 patients formed group 1 while 247 formed group 2. The main differences observed were in the form of a clear increase in the percentage of patients with sleep-related breathing disorders, sleep-related movement disorder, and the hypersomnias on comparison of distribution over the first 4 years versus the last 4 years; while a clear decline was seen in the number of patients with insomnia and parasomnias. A 3-fold increase was observed in the number of patients in whom polysomnography was obtained.

Conclusion:

The distribution of various sleep disorders as seen in a neurology service-based sleep clinic is demonstrated in this study. Increasing referrals for sleep-disordered breathing, restless legs syndrome, and fewer referrals for insomnia and parasomnias might reflect on changing physician and patient awareness in our community.  相似文献   
79.
Malaria, a global threat to the human population, remains a challenge partly due to the fast-growing drug-resistant strains of Plasmodium species. New therapeutics acting against the pathogenic asexual and sexual stages, including liver-stage malarial infection, have now attained more attention in achieving malaria eradication efforts. In this paper, two previously identified potent antiplasmodial hydroxyethylamine (HEA) compounds were investigated for their activity against the malaria parasite''s multiple life stages. The compounds exhibited notable activity against the artemisinin-resistant strain of P. falciparum blood-stage culture with 50% inhibitory concentrations (IC50) in the low micromolar range. The compounds'' cytotoxicity on HEK293, HepG2 and Huh-7 cells exhibited selective killing activity with IC50 values > 170 μM. The in vivo efficacy was studied in mice infected with P. berghei NK65, which showed a significant reduction in the blood parasite load. Notably, the compounds were active against liver-stage infection, mainly compound 1 with an IC50 value of 1.89 μM. Mice infected with P. berghei sporozoites treated with compound 1 at 50 mg kg−1 dose had markedly reduced liver stage infection. Moreover, both compounds prevented ookinete maturation and affected the developmental progression of gametocytes. Further, systematic in silico studies suggested both the compounds have a high affinity towards plasmepsin II with favorable pharmacological properties. Overall, the findings demonstrated that HEA and piperidine possessing compounds have immense potential in treating malarial infection by acting as multistage inhibitors.

Malaria, a global threat to the human population, remains a challenge partly due to the fast-growing drug-resistant strains of Plasmodium species.  相似文献   
80.
BACKGROUND: Clinical information about bipolar disorder (BPD) in preschool-age (3-7 years old) children is extremely limited. This study examined clinical presentations, applicability of the DSM-IV diagnostic criteria, comorbidity, recovery and relapse rates, as well as some treatment strategies used in the management of BPD in preschoolers. METHODS: The charts of 26 outpatient children, ages 3-7, refereed to a child psychiatry outpatient clinic with mood and behavioral symptoms, were retrospectively reviewed. RESULTS: The majority of the patients were referred with the tentative diagnosis of ADHD but the most common diagnoses made by child and adolescent psychiatrists at the time of initial evaluation were BPD NOS (61.5%), followed by BPD I (26.9%), and mood disorder NOS (23.1%). Thirty-eight percent of the patients had one or more comorbid diagnoses. The most common presenting symptoms were irritability (84.6%) and aggression (88.5%). The most widely prescribed class of medications after diagnosis in the clinic was atypical antipsychotics and mood stabilizers. Twenty-six percent of the patients were treated with a combination of atypical antipsychotics and mood stabilizers. LIMITATIONS: Retrospective design; small sample size; lack of a comparison group. CONCLUSIONS: The course of BPD with onset in preschool years is complicated with high recovery and relapse rates. The questions of development of age-appropriate diagnostic criteria, long-term prognosis and treatment strategies used in this population require further intensive investigation.  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