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   671篇
  免费   49篇
  国内免费   4篇
耳鼻咽喉   9篇
儿科学   10篇
妇产科学   7篇
基础医学   66篇
口腔科学   5篇
临床医学   68篇
内科学   171篇
皮肤病学   4篇
神经病学   29篇
特种医学   17篇
外科学   131篇
综合类   28篇
预防医学   60篇
眼科学   4篇
药学   65篇
中国医学   5篇
肿瘤学   45篇
  2024年   1篇
  2023年   6篇
  2022年   16篇
  2021年   39篇
  2020年   22篇
  2019年   23篇
  2018年   36篇
  2017年   14篇
  2016年   17篇
  2015年   22篇
  2014年   32篇
  2013年   27篇
  2012年   49篇
  2011年   53篇
  2010年   39篇
  2009年   25篇
  2008年   31篇
  2007年   39篇
  2006年   23篇
  2005年   32篇
  2004年   32篇
  2003年   30篇
  2002年   21篇
  2001年   7篇
  2000年   8篇
  1999年   10篇
  1998年   6篇
  1997年   6篇
  1996年   2篇
  1995年   7篇
  1994年   3篇
  1993年   1篇
  1992年   4篇
  1991年   6篇
  1990年   1篇
  1989年   6篇
  1988年   4篇
  1987年   5篇
  1986年   4篇
  1985年   1篇
  1984年   2篇
  1983年   2篇
  1982年   2篇
  1981年   1篇
  1980年   1篇
  1979年   1篇
  1978年   1篇
  1977年   2篇
  1975年   1篇
  1974年   1篇
排序方式: 共有724条查询结果,搜索用时 10 毫秒
101.
This study aimed to investigate the possible protective effects of aliskiren against doxorubicin (DXR)‐induced cardiorenal injury and to identify the mechanisms involved. Intraperitoneal administration of DXR (15 mg/kg, body weight, as a single dose) caused significant induction in the levels of angiotensin I, caspase‐3, lactate dehydrogenase (LDH), lipid peroxidation malondialdehyde (MDA), urea, and creatinine. Concomitant decline in the levels of albumin and total protein in plasma, reduction in reduced glutathione (GSH), and antiperoxidative enzyme superoxide dismutase (SOD) levels followed by ultrastructural alterations in the myocardial and renal tissues were also observed. Oral administration of aliskiren (100 mg/kg, for a period of 14 days) significantly prevented all these DXR‐induced adverse effects and maintained the rats near to normal status. However, telmisartan (10 mg/kg) pretreatment has shown slight protection in DXR‐induced renal injury as evidenced by broadening of podocyte foot process and narrowing of slit pore diameter. The results of aliskiren were compared with telmisartan which was used as reference in this study. These results suggested that aliskiren has protective effects against acute model of DXR‐induced cardiotoxicity and nephrotoxicity, implying that plasma renin activity plays a role in DXR‐induced cardio‐renal injury.  相似文献   
102.
Objectives: The aim of this study was to assess the safety and probability of adverse events associated with the use of 75 mg pregabalin post hemodialysis (pHD) among patients with UP. Methods: A cross-sectional study done among the hemodialysis patients suffering from uremic pruritus (UP) Aljaber Kidney Center (AJKC), Al-Ahsa, Eastern Province, Saudi Arabia. Assessment for the safety profile of pregabalin was done using Naranjo’s algorithm. A predictive model was developed using binary multiple logistic regression to explore association of patients’ demographics and risk factors with the occurrence of AEs. Throughout statistical significance level was considered significant at 0.05. Key findings: Assessment of safety of pregabalin revealed that somnolence and dizziness were the two frequent adverse events followed by constipation, weight gain and edema. However, it was noticed that female patients aged less than 50 years were found to be at a higher risk in comparison with men. Moreover, those patients having one comorbid complication (i.e. hypertension or diabetes mellitus alone) were at a higher risk of somnolence, weight gain and dry mouth. Conclusion: Naranjo’s quantification for the possibility and probability of adverse events reflect that all the events were probable. Age, gender and comorbid medical conditions are some of the factors that might have clinical association with the occurrence of the AEs.  相似文献   
103.
Objective: To determine the perceived risk of developing cancer in a suburban community in Malaysia. Methods:A cross sectional study using a simple random sampling was conducted among residents aged 18 years old and above(n=520) who had never been diagnosed with cancer, in selected households in a suburban area of Pahang state inMalaysia. The study instruments were a validated questionnaire on risk perception, an automatic blood pressure monitor,a weighing scale and a measuring tape. Data were analyzed using IBM SPSS Statistics for Windows, Version 20.0 andthe p value was taken at p they were at risk cancer, whilst the perceived severity was 41.3 percent. Multivariable analysis showed a significantassociation only for a family history of cancer (adjusted OR of 4.80; 95% CI = 1.45-15.82) (p=0.010) among thispopulation. Conclusion: The perceived risk of developing cancer in the selected suburban community of Pahang state inMalaysia is low as compared to that for other non-communicable diseases in this country, whilst the perceived severitywas higher than for other diseases. Thus, considering the importance of correct perceptions for behavioral changes,more health education and promotion is needed to make the community better aware of the actual threat of cancer.  相似文献   
104.
The distribution of nitric oxide producing neurones in the medulla oblongata of the cat was investigated using nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase histochemistry, and nitric oxide synthase (NOS) immunohistochemistry. The pattern of staining obtained with both methods was found to be similar. Strongly diaphorase and NOS reactive neurones were present in the paramedian and lateral tegmental fields, including the regions occupied by the Al/C1 catecholamine cell groups, the nucleus ambiguus and lateral reticular nucleus, and in a number of sensory nuclei including the nucleus of the tractus solitarius and the dorsal column nuclei. The extent of co-localization of NADPH-diaphorase with a number of neuropeptides and neurotransmitters was investigated by combining NADPH-diaphorase histochemistry with immunocytochernisty for neuropeptide Y, somatostatin, glutamate, cholecystokinin and tyrosine hydroxylase. NADPH-diaphorase reaction product was observed in neurones immunoreactive for glutamate and somatostatin. These double-labelled cells were found in the paramedian region, lateral reticular field, the nucleus prepositus hypoglossi and in the rostral nucleus of the tractus solitarius. In the rostral ventrolateral medulla NADPH-diaphorase/somatostatin immunoreactive cells were found in the paragigantocellular nucleus. NADPHdiaphorase/glutamate immunoreactive cells overlapped the nucleus ambiguus, the lateral reticular nucleus and the A1/C1 catecholaminergic cell groups. In addition, a few NADPH-diaphorase/glutamate immunoreactive cells were found in the paraolivary area and gigantocellular tegmental field, in the external cuneate and infratrigerninal nuclei. The functional implications of the co-localization of nitric oxide with these neurotransmitters in areas of the medulla concerned with cardiovascular regulation is discussed.  相似文献   
105.
To reveal neurones in the cat medulla oblongata involved in carotid baroreceptor/chemoreceptor reflexes, the distribution of c-Fos oncoprotein immunoreactivity was studied following electrical stimulation of the right carotid sinus nerve. The neurochemistry of the activated neurones was investigated using antisera to tyrosine hydroxylase, neuropeptide Y, somatostatin, and glutamate. Nitric oxide containing neurones were identified using antiserum to nitric oxide synthase (NOS) and by the histochemical localization of nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase. Following sinus nerve stimulation numerous c-Fos-IR cells were detected both ipsilaterally and contralaterally in the nucleus tractus solitarii, the area postrema and throughout the ventrolateral medulla. Dual labelling studies revealed that 3.3% of c-Fos- immunoreactive cells in the nucleus tractus solitarii were also immunoreactive for tyrosine hydroxylase. The double labelled cells were scattered within the medial and ventrolateral subnuclei, predominantly rostral to obex. A higher proportion (10.3%) of c-Fos-IR cells in the ventrolateral medulla also showed tyrosine hydroxylase immunoreactivity. Caudal to obex, these were scattered in the reticular formation between the spinal trigeminal nucleus and the lateral reticular nucleus, while more rostrally they were found within the lateral reticular nucleus, the nucleus ambiguus and the lateral tegmental field. Cells expressing c-fos and reactive for glutamate, neuropeptide Y or NADPH-diaphorase (or NOS) were only rarely seen, and co-localization of c-Fos and somatostatin immunoreactivities was not seen. These results suggest that of the neurones forming pathways within the medulla activated on carotid sinus nerve stimulation, presumably mediating baro- and chemoreceptor reflexes, relatively few utilize catecholamines, glutamate, neuropeptide Y or nitric oxide as their transmitter substance.  相似文献   
106.
Pharmaceutical Research - Chemotherapy for glioblastoma multiforme (GBM) remains ineffective due to insufficient penetration of therapeutic agents across the blood–brain barrier (BBB) and...  相似文献   
107.
108.
Esophageal leiomyoma (EL) is rare but still the most common benign tumor of the esophagus. Extra-mucosal enucleation (EME) is the treatment of choice. Many recent reports have favored esophageal resection for giant Esophageal leiomyomas (ELs). The consequence of esophageal resection is well known and it would be radical to consider it as a preferred treatment for giant EL since most of them are still benign. We share case series of five giant ELs managed by EME, avoiding a mucosal breach and hence avoiding potentially morbid esophageal resections.  相似文献   
109.
110.
Aims: The aim of this study was to evaluate the left ventricular (LV) diastolic dysfunction in rheumatoid arthritis (RA) patients without clinically evident cardiovascular manifestations and to estimate whether there is any correlation between RA disease severity and disability and LV diastolic dysfunction. Methods: The study was a cross‐sectional study involving 53 patients (47 female and 6 male) with RA without clinically evident heart disease and 53 healthy subjects (47 female and 6 male) who served as a control group. Both groups were matched for age and sex. Echocardiographic and Doppler studies were conducted in all patients with RA and control subjects. Results: Of 17 cardiac parameters assessed, only two were abnormal. None of the specific cardiac diastolic dysfunction parameters were significantly different in RA patients compared to the control group. There was no significant correlation between diastolic function values in RA patients and value of Disease Activity Score 28 (DAS‐28) and value of Health Assessment Questionnaires Disability Index (HAQDI). Atrial (A) wave velocity was greater in RA patients compared to the control group (0.71 [0.58–0.83] vs. 0.61 [0.51–0.71]; P < 0.04). However, interventricular relaxation time (IVRT) ([73.08 ± 9.92 vs. 70.74 ± 9.02], P = 0.207), lower E/A ratio (1.27 [1.02–1.56] vs. 1.42 [1.20–1.68], P = 0.102), diastolic dysfunction parameters according to Redfield Classification (25 [47.2%] vs. 27 [50.9%] P = 0.56), diastolic dysfunction using E/A (P = 0.321) and tissue doppler imaging (E/E′) (P = 0.148) were not different. Conclusion: Prevalence of diastolic dysfunction in the rheumatoid arthritis group (47.2%) was not different from controls (50.9%). LV diastolic function had no significant correlation with RA disease severity and duration of disease.  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