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   2999篇
  免费   109篇
  国内免费   40篇
耳鼻咽喉   72篇
儿科学   133篇
妇产科学   81篇
基础医学   217篇
口腔科学   135篇
临床医学   216篇
内科学   617篇
皮肤病学   80篇
神经病学   176篇
特种医学   236篇
外科学   544篇
综合类   165篇
预防医学   81篇
眼科学   75篇
药学   167篇
  1篇
中国医学   63篇
肿瘤学   89篇
  2023年   20篇
  2022年   31篇
  2021年   76篇
  2020年   49篇
  2019年   46篇
  2018年   66篇
  2017年   59篇
  2016年   86篇
  2015年   82篇
  2014年   107篇
  2013年   140篇
  2012年   198篇
  2011年   203篇
  2010年   130篇
  2009年   119篇
  2008年   145篇
  2007年   209篇
  2006年   180篇
  2005年   187篇
  2004年   157篇
  2003年   106篇
  2002年   116篇
  2001年   49篇
  2000年   42篇
  1999年   43篇
  1998年   55篇
  1997年   46篇
  1996年   52篇
  1995年   28篇
  1994年   25篇
  1993年   30篇
  1992年   14篇
  1991年   10篇
  1990年   10篇
  1989年   28篇
  1988年   23篇
  1987年   16篇
  1986年   22篇
  1985年   19篇
  1984年   7篇
  1983年   5篇
  1982年   17篇
  1981年   10篇
  1980年   12篇
  1978年   8篇
  1977年   11篇
  1976年   9篇
  1975年   11篇
  1974年   6篇
  1972年   4篇
排序方式: 共有3148条查询结果,搜索用时 178 毫秒
991.
We aimed to establish that a bronchoscopic view can be as reliable as microbiology, and support an empirical tracheobronchial fungal infection (TBFI) treatment decision. We retrospectively studied 95 respiratory failure patients with suspected TBFI admitted to the intensive-care unit (ICU) in 2008 with sticky secretions, hyperaemic mucosa, and whitish plaques on bronchoscopic view. Patients not suspected of having TBFI were chosen as a control group (n = 151). Broncheoalveolar lavage (BAL) fluid was cultured, and biopsy samples were taken from the lesions. Biopsy samples positive for fungi were defined as ‘proven', only BAL-positive (+ fungi) cases were ‘probable TBFI', and BAL-negative (– fungi) cases were ‘possible TBFI'. BAL (+ fungi) and BAL (– fungi) in the control group were defined as ‘colonization' and ‘no TBFI', respectively. The sensitivity, specificity and positive and negative predictive values of BAL (+ fungi) were 85.1% (63/74), 81.4% (140/172), 66.3% (63/95), and 92.7% (140/151), respectively. Biopsies were performed in 78 of 95 patients, and 28 were proven TBFI with fungal elements, and 100% were BAL (+ fungi). Probable TBFI was seen in 30 of 95 patients with BAL (+ fungi), and possible TBFI (BAL(– fungi)) in 25 of 95. Among the 95 patients, microbiology revealed fungi (90.5% Candida species; 9.5% Aspergillus) in 63 (66.3%). In the controls, the colonization and no TBFI rates were 11 of 151 and 140 of 151, respectively. Observing sticky secretions, hyperaemic mucosa and whitish plaques by bronchoscopy is faster than and may be as reliable as microbiology for diagnosing TBFI. These findings are relevant for empirical antifungal therapy in suspected TBFI patients in the ICU.  相似文献   
992.

Background

This retrospective study aimed to investigate the diagnostic relation between the mean platelet volume (MPV) and supraventricular tachyarrhythmia (SVT) in patient with documented atrial tachyarrhythmia in the emergency department (ED).

Methods

Two study groups were compared; a SVT group with arrive at the ED with documented SVT (n=122) and 100 healthy adult without any palpitation symptom, arrhythmic disease, and with normal physical examination results that were brought for checkups to the cardiology polyclinic were classified as control group. Blood samples were obtained from all patients for determining the hematologic counts and MPV during first hour in ED period.

Results

In terms of the focus of the study, hemoglobin, neutrophil count, mean cell volume (MCV), red cell distribution width (RDW), platelet, white blood cell (WBC), and lymphocyte counts were similar in both group (p>0.05). MPV in the SVT group was significantly higher than in the control group (9.12±1.22 flvs 8.64±0.89 fl, p<0.001). Multivariate logistic regression analysis showed that just MPV was independent predictor of SVT in patients with palpitation in ED (odds ratio [OR] 8.497, 95% confidence interval (6.181 to 12.325), p=0.012).

Conclusion

The present study described that MPV is helpful parameter for the diagnosis of SVT in emergency department, for the first time in the literature.  相似文献   
993.

Background

The global burden of sexually transmitted infections (STIs) is a major concern to the World Health Organization (WHO).

Objective

To document STIs treated by Bapedi traditional healers and their methods of diagnoses in the Limpopo Province, South Africa.

Methods

A semi-structured questionnaire with closed and open-ended questions was used to collect data from 34 traditional healers, during a face-to-face interview.

Results

Five seemingly dissimilar STIs; gonorrhoea, chlamydia, HIV/AIDS, nta (Bapedi-terminology) and syphilis were identified as being treated by Bapedi traditional healers. With the exclusion of HIV/AIDS, all STIs are known by healers via their vernacular names. Not all of the recorded STIs are treated by all the questioned traditional healers. Generally, diagnosis of these infections was based primarily on the presentation of symptoms and certain behavioural traits; mostly unprotected sexual intercourse with multiple partners.

Conclusion

The current study concludes that Bapedi traditional healers play an important role in the treatment STIs in the Limpopo Province. Of concern is their diagnosis which is based primarily on the presentation of symptoms and behavioural traits, which are not always accurate indicators. Thus, to make their contribution to the treatment and management of STIs beneficial, they have to receive elementary training in diagnostic methods particularly for HIV/AIDS.  相似文献   
994.
Autoantibodies to glutamic acid decarboxylase are found in some rare neurological diseases. However, acute peripheral neuropathy associated with antiglutamic acid decarboxylase autoimmunity has not been reported previously. Here we report a case of a patient who presented with acute cranial and peripheral neuropathy in association with the presence of serum antiglutamic acid decarboxylase antibodies. A 13-year-old boy was admitted to our pediatric neurology clinic with diplopia due to sixth cranial nerve palsy and ascending motor weakness in all extremities. The nerve conduction studies showed bilateral motor and sensory demyelinating neuropathy. Full recovery was achieved following intravenous immunoglobulin treatment. Glutamic acid decarboxylase autoimmunity–associated neurological diseases spectrum may also include acute demyelinating peripheral neuropathy.  相似文献   
995.
996.

Objective

The aim of this study is testing the value of H-FABP in the early diagnosis of ACS alone or with routinely used biomarkers such as myoglobin, CK-MB, and cTn I in patients who admitted to emergency department (ED) with complaint of chest pain and suspected acute coronary syndrome.

Material and Methods

This prospective and cross-sectional study was performed at the Emergency Department of University hospital between June 2009 and September 2010. Patients who were admitted with chest pain within first 48 hours and suspected ACS were enrolled to the study. Blood samples were taken for CK-MB, myoglobin, cTnI and H-FABP The patients were divided into two groups (ACS and non ACS). Statistical analyse were used for relation of biomarkers with diagnosis of ACS.

Results

A 66 patients were included to the study. H-FAPB values were positive in15.2% patients. When H-FABP was added to routinely used biomarkers in the diagnosis of ACS, increasing was observed in all sensitivity, specificity, PPV and NPV values. However, this increase was not stastistically significant.

Conclusion

H-FABP did not provide any significant change in early diagnosis and exclusion of ACS diagnosis when used either alone or combination with routinely used biomarkers  相似文献   
997.
Background: In this study, levels of malondialdehyde (MDA), which is a significant product of lipid peroxidation (LPO), total oxidant status (TOS), total antioxidant capacity (TAOC), and the oxidative stress index (OSI), a novel value as a marker of periodontal disease activity, are investigated in serum and saliva from patients with chronic (CP) and generalized aggressive (GAgP) periodontitis. Methods: A total of 98 patients (33 with CP, 35 patients with GAgP, and 30 periodontally healthy controls) enrolled in the study. After clinical measurements and sample collection, the MDA level, TOS, and TAOC were measured by high‐performance liquid chromatography and a novel automatic colorimetric method. The OSI was calculated as [(TOS/TAOC) × 100]. Results: Although the salivary MDA levels and serum and salivary TOS and OSI values were significantly higher in the periodontitis groups than in the control group (P <0.05), the serum and salivary TAOC levels were significantly lower, and no significant difference in serum MDA levels was found (P >0.05). Furthermore, oxidative stress parameters were higher in the GAgP group than in the CP group (except the serum and salivary MDA levels and serum TAOC). Significant positive and negative correlations were observed between periodontal parameters and the MDA levels and TOS, TAOC, and OSI values (except serum MDA) (P <0.05). Conclusions: The present findings suggest that an increased TOS and decreased TAOC, rather than LPO, play important roles in the pathology of periodontitis and are closely associated with clinical periodontal status. Furthermore, the OSI may be a useful and practical parameter for evaluating periodontal disease activity.  相似文献   
998.
Dural arteriovenous fistulas (DAVFs) are rare lesions. The most common locations of DAVFs are cavernous, sigmoid and transverse sinuses. Anterior cranial fossa is one of the less frequent placement for DAVFs and the risk of hemorrhage in this region is increased. Reported hemorrhage risks have been ranged from 62 to 91 %, and an aggressive clinical course is more likely than a benign clinical course. A 47-year-old man was admitted to our emergency room with headache and the computed tomography revealed frontal hemorrhage. Neurological examination was normal. We applied cerebral angiography in our interventional neurology department and an anterior cranial fossa DAVFs, supplied by bilateral ophthalmic-ethmoidal arteries, was determined. DAVFs are a rare cause of intracranial hemorrhages and in the literature anterior cranial fossa DAVFs have been reported scarcely, so that we aimed to present this rare entity.  相似文献   
999.
1000.
This article describes an alternative impression technique for the fabrication of an implant-supported bar overdenture using the duplicated satisfactory interim denture as a custom tray for the implant-level impression. The primary advantage of this technique is that all the information needed for the definitive prosthesis fabrication is obtained from the interim denture and then transferred to the laboratory in a single appointment. However, this technique may be contraindicated for severely misaligned implants that require extensive reduction of the duplicated denture.  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