全文获取类型
收费全文 | 5776篇 |
免费 | 538篇 |
国内免费 | 30篇 |
专业分类
耳鼻咽喉 | 41篇 |
儿科学 | 181篇 |
妇产科学 | 231篇 |
基础医学 | 774篇 |
口腔科学 | 238篇 |
临床医学 | 706篇 |
内科学 | 1153篇 |
皮肤病学 | 206篇 |
神经病学 | 463篇 |
特种医学 | 160篇 |
外科学 | 573篇 |
综合类 | 133篇 |
一般理论 | 7篇 |
预防医学 | 479篇 |
眼科学 | 117篇 |
药学 | 457篇 |
中国医学 | 50篇 |
肿瘤学 | 375篇 |
出版年
2023年 | 108篇 |
2022年 | 208篇 |
2021年 | 330篇 |
2020年 | 210篇 |
2019年 | 322篇 |
2018年 | 366篇 |
2017年 | 229篇 |
2016年 | 226篇 |
2015年 | 238篇 |
2014年 | 283篇 |
2013年 | 315篇 |
2012年 | 484篇 |
2011年 | 423篇 |
2010年 | 193篇 |
2009年 | 148篇 |
2008年 | 246篇 |
2007年 | 203篇 |
2006年 | 186篇 |
2005年 | 158篇 |
2004年 | 143篇 |
2003年 | 100篇 |
2002年 | 110篇 |
2001年 | 66篇 |
2000年 | 67篇 |
1999年 | 68篇 |
1998年 | 23篇 |
1997年 | 27篇 |
1995年 | 22篇 |
1993年 | 19篇 |
1992年 | 57篇 |
1991年 | 44篇 |
1990年 | 43篇 |
1989年 | 38篇 |
1988年 | 34篇 |
1987年 | 37篇 |
1986年 | 29篇 |
1985年 | 26篇 |
1984年 | 23篇 |
1982年 | 18篇 |
1981年 | 21篇 |
1977年 | 23篇 |
1974年 | 33篇 |
1973年 | 21篇 |
1972年 | 36篇 |
1971年 | 29篇 |
1970年 | 36篇 |
1969年 | 29篇 |
1968年 | 20篇 |
1967年 | 18篇 |
1966年 | 27篇 |
排序方式: 共有6344条查询结果,搜索用时 31 毫秒
101.
Ali Akbar Velayati Parissa Farnia Mohadese Mozafari Maryam Fatemeh Sheikholeslami Mona Afraei Karahrudi Payam Tabarsi Sven Hoffner 《The American journal of tropical medicine and hygiene》2014,90(1):99-105
We determined the prevalence of rifampin-monoresistant tuberculosis (RMR-TB) in Iran. Because development of RMR-TB is not common, we also identified the major risk factors associated with RMR-TB reported from different provinces of Iran. Data for 3,020 TB patients who remained or became smear positive after two, four, six, and nine months of standard first-line chemotherapy were retrospectively analyzed. Of 3,020 patients, 1,242 patients (41.1%) were culture and DNA positive for Mycobacterium tuberculosis. Of these patients, 73 (7.4%) patients had monoresistant isolates to rifampin, which was significantly higher than that for multidrug-resistant TB (5.8%). The average rate of RMR-TB in the studied population ranged from 5% to 10%. Classical investigation showed that 33.6% of patients had either a previous or family history of TB. Molecular epidemiology methods (i.e., spoligotyping and Mycobacterium intespersed repetitive unit–variable number tandem repeat), defined transmission link in three clusters (13%). These results outline the urgent need for a comprehensive plan for detection and treatment of RMR-TB cases. 相似文献
102.
103.
Mozhgan Afkhamizadeh Maryam Sahebari Seyyed-Reza Seyyed-Hoseini 《Rheumatology international》2014,34(8):1145-1151
Rheumatoid arthritis (RA), the most prevalent autoimmune arthritis worldwide, usually presents with a circannual manner and, meanwhile, follows a circadian rhythm for symptoms like morning stiffness. Therefore, association between RA and some hormones such as melatonin (MLT) and vitamin D, whose serum values are related to body circadian rhythms or seasonal variations, has become more noticeable recently. Since some studies proposed that RA patients show altered MLT circadian rhythms, especially in concordance with symptoms, in this research, we present the correlation between MLT serum values and RA disease activity score (DAS28ESR). The current cross-sectional study was carried out on 80 volunteers (60 patients and 20 healthy controls). Fifty percent of the participants in each group were sampled in cold, and the same percentage were sampled in warm seasons at 8 a.m. Disease activity was estimated utilizing DAS28ESR. Patients with possible known confounders of MLT secretion were excluded. A commercial MLT ELISA kit was employed to measure MLT. Statistical analysis was conducted by SPSS-11 software. This study outlined higher serum values of MLT in RA patients compared with controls (P = 0.006, z = ?2.73). However, MLT did not correlate with DAS in patients (P = 0.45, r = ?0.09). GLM analysis demonstrated that DAS28ESR, age, disease duration, medications, gender, and season of sampling had no influence on serum MLT. However, newly diagnosed RA patients presented higher MLT values than established ones (P = 0.03, t = ?2.2). A cutoff point value of 23 pg/mL (63.3 % sensitivity and 90 % specificity) for MLT was computed between patients and controls. This study denoted that morning MLT serum values are higher in RA patients than in healthy volunteers. However, MLT and RA disease activity or other disease characteristics do not correlate. MLT serum values were higher in newly diagnosed RA patients than established ones. 相似文献
104.
Maryam Abbasian Mehri Delvarianzadeh Hossein Ebrahimi Farideh Khosravi Pirasteh Nourozi 《Diabetes & Metabolic Syndrome: Clinical Research & Reviews》2018,12(4):497-500
Aims
This study aimed to investigate the relationship between the total antioxidant capacity (TAC) and Malondialdehyde (MDA) with number of metabolic syndrome (Mets) components on the personnel working in Shahroud University of Medical Sciences.Methods
This cross-sectional study was conducted on 167 personnel aged 30–60 years old. ATP III criteria were used to diagnose patients with MetS. Oxidative stress indicators were measured. The data was analyzed via one-way ANOVA, and Pearson and Spearman correlation coefficients.Results
The result showed that TAC had a significant positive correlation with HDL and a significant negative correlation with abdominal obesity. In addition, there was a significant positive association between the level of MDA and age, BMI, abdominal obesity, diastolic blood pressure, triglycerides, and LDL; however, it had a negative significant correlation with HDL.Conclusions
The measurement of TAC and MDA biomarkers can increase the early diagnosis of patients at risk of developing Mets. 相似文献105.
Soliman AT Al Khalaf F Alhemaidi N Al Ali M Al Zyoud M Yakoot K 《Metabolism: clinical and experimental》2008,57(1):95-102
The objective of the study was to determine the degree of linear growth retardation of patients with vitamin D deficiency rickets at presentation and the magnitude of catch-up growth in relation to their calcium (Ca) homeostasis and hormones affecting it before and after treatment. This prospective study recorded the anthropometric data and measured the circulating 25-hydroxy vitamin D (25-OH-D), insulin-like growth factor I (IGF-I), parathyroid hormone, Ca, phosphate, and alkaline phosphatase concentrations in 46 infants and children with nutritional (vitamin D deficiency) rickets before and 6 months or more after treatment with one intramuscular injection of vitamin D3 megadose (300000 IU). Forty normal age- and sex-matched children were included as controls for the auxological data. At presentation, patients' mean age = 13.1 +/- 1.1 months, length standard deviation scores (LSDS) = -1.5 +/- 0.2, and body mass index = 16.3 +/- 0.85. They were significantly shorter and had markedly lower growth velocity standard deviation scores (GVSDS) compared with normal controls (LSDS = 0.25 +/- 0.18 and 0.31 +/- 0.22, respectively). Six months after treatment, the LSDS increased significantly in patients to -0.45 +/- 0.13, with a significantly increased GVSDS (2.76 +/- 0.45) and body mass index (16.9 +/- 0.65). They were still shorter but with significantly higher GVSDS compared with normal controls. Serum Ca and phosphate concentrations increased from 2.07 +/- 0.25 and 1.23 +/- 0.24 mmol/L, respectively, before treatment to 2.44 +/- 0.2 and 1.94 +/- 0.2 mmol/L, respectively, after treatment. Serum alkaline phosphatase and parathyroid hormone concentrations decreased from 1183 +/- 219 U/L and 294 +/- 87 pg/mL, respectively, before treatment to 334 +/- 75 U/L and 35.2 +/- 15.2 pg/mL, respectively, after treatment. The 25-OH-D level increased from 4.5 +/- 0.56 ng/mL before treatment to 44.5 +/- 3.7 ng/mL after treatment. Circulating concentrations of IGF-I increased significantly after treatment (52.2 +/- 18.9 ng/mL) vs before treatment (26.6 +/- 12.8 ng/mL). The 25-OH-D concentrations were correlated significantly with the IGF-I levels before and after treatment (r = 0.603 and r = 0.59, respectively; P < .001). The GVSDS after treatment was correlated with the increase of IGF-I and 25-OH-D levels (r = 0.325 and r= 0.314, respectively; P < .01). These data denote that the accelerated linear growth after treatment of nutritional vitamin D deficiency is mediated through activation of the growth hormone/IGF-I system and suggests an important role of vitamin D as a link between the proliferating cartilage cells of the growth plate and growth hormone/IGF-I secretion. Three different sequential stages of vitamin D deficiency can be recognized according to the clinical/radiological, biochemical, and hormonal data of patients at presentation. 相似文献
106.
Dr. Christoph Brochhausen Christoph B. Wiedenroth Dr. Maryam Ghalibafian Prof. Dr. Andreas Schwarting Dr. Jürgen Bohl Prof. C. James Kirkpatrick MD PhD DSc FRCPath FBSE 《Intensivmedizin und Notfallmedizin》2008,45(1):31-36
Heat stroke is a lifethreatening disease with high mortality, characterized by a body temperature of over 40°C and clinical symptoms of central nervous system dysfunction. However, the pathophysiological mechanisms are not fully understood. A new interesting explanation for the clinical symptoms could be a systemic inflammatory response due to barrier dysfunction in the intestine leading to endothelial damage and a syndrome of multiorgan dysfunction. We describe a 37-year-old male patient who collapsed while working in a vineyard in an environmental temperature of 32°C with a body temperature of 42.5°C. Despite intensive care treatment, he died with symptoms of shock and multiorgan dysfunction. Autopsy was performed followed by the histological evaluation of paraffin-embedded tissue. As correlates for clinical shock symptoms, shock kidneys and shock liver could be demonstrated. Furthermore, multiple microthrombi were found, together with clinically undetectable fibrinogen values. Finally, the patient died due to massive diffuse gastrointestinal bleeding and bleeding in pleural and pericardial cavities. No signs of severe edema of the central nervous system were detectable. This case supports the hypothesis that in heat stroke endothelial damage occurs with consecutive cascade of inflammatory and coagulatory reactions, which may play a critical pathophysiological role. 相似文献
107.
Rezaei N Farhoudi A Pourpak Z Aghamohammadi A Ramyar A Moin M Gharagozlou M Movahedi M Mohammadpour B Mirsaeid Ghazi B Izadyar M Mahmoudi M 《Iranian journal of allergy, asthma, and immunology》2004,3(1):37-40
Cyclic neutropenia is a rare immunodeficiency syndrome, characterized by regular periodic oscillations in the circulating neutrophil count from normal to neutropenic levels through 3 weeks period, and lasting for 3-6 days. In order to determine the clinical features of cyclic neutropenia, this study was performed. Seven patients with cyclic neutropenia (3 males and 4 females), who experienced neutropenic periods every 3 weeks (5 with severe and 2 with moderate neutropenia), were investigated in this study. They had been referred to Iranian Primary Immunodeficiency Registry during 23 years (1980-2003). The range of patients' ages was from 7 to 13 years (median 11 years). The median age at the onset of the disease was 12 months (1 month- 2 years) and the median age of diagnosis was 2 (1.5-5) years, with a median diagnosis delay of 1 year (2 months- 5 years). Neutropenia was associated with leukopenia (3 patients), anemia (3 patients), and thrombocytopenia (1 patient). Patients were asymptomatic in healthy phase, but during the episode of neutropenia suffered from aphthous ulcers, abscesses and overwhelming infections. The most commonly occurred manifestations were: otitis media (6 cases), oral ulcers (5 cases), abscesses (4 cases), pneumonia (3 cases), diarrhea (3 cases), oral candidiasis (3 cases), cutaneous infections (2 cases), and periodontitis (2 cases). One of these patients subsequently died because of recurrent infections. Unusual, persistent or severe infections should be the initiating factors to search for an immune deficiency syndrome such as cyclic neutropenia, because a delay in diagnosis may result in chronic infection, irretrievable end-organ damage or even death of the patient. 相似文献
108.
Manijheh Sabokdast Mehran Habibi-Rezaei Ali Akbar Moosavi-Movahedi Maryam Ferdousi Effat Azimzadeh-Irani Najmeh Poursasan 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2015,23(1)
Background
Diabetes mellitus is characterized jointly by hyperglycemia and hyperinsulinemia that make insulin more prone to be glycated and evolve insulin advanced glycation end products (Insulin- AGE). Here, we report the effect of beta-hydroxy butyrate (BHB) (the predominant ketone body) on the formation of insulin-AGE, insulin glycation derived liposomal lipid peroxidation and insulin-AGE toxicity in microglial cells.Methods
The inhibitory effect of BHB was monitored as a result of insulin incubation in the presence of glucose or fructose using AGE-dependent fluorescence, Tyr fluorescence as well as anilinonaphthalenesulfonate (ANS) andthioflavin T (ThT) binding, and circular dichroism (CD) investigations. To study lipid peroxidation induced by insulin glycation, thiobarbituric acid (TBA) assay and thiobarbituric acid reactive substance (TBARS) monitoring were used. The effect of insulin–AGE on microglial viability was investigated by 3-(4, 5 dimethylthiazol-2-yl)—2, 5-diphenyltetrazoliumbromide (MTT) cell assay and Annexin V/propidium iodide (PI) staining.Results
Here we are reporting the inhibitory effect of BHB on insulin glycation and generation of insulin-AGE as a possible explanation for insulin resistance. Moreover, the protective effect of BHB on consequential glycation derived liposomal lipid peroxidation as a causative event in microglial apoptosis is reported.Conclusion
The reduced insulin fibril formation, structural inertia to glycation involved conformational changes, anti-lipid peroxidation effect, and increasing microglia viability indicated the protective effect of BHB that disclose insight on the possible preventive effect of BHB on Alzheimer’s disease. 相似文献109.
Farzin Rezaei Maryam Emami Shakiba Zahed Mohammad-Javad Morabbi Mohammadhadi Farahzadi Shahin Akhondzadeh 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2015,23(1)
Background
The objective of this randomized, double-blind, placebo-controlled study was to evaluate the efficacy of sustained-release methylphenidate (MPH-SR) in treatment of methamphetamine dependence.Methods
Fifty-six individuals who met DSM-IV-TR criteria for methamphetamine dependence participated in this 10-week trial. The participants were randomly allocated into two groups and received 18 to 54 mg/day sustained-released methylphenidate or placebo for 10 weeks. Craving was evaluated by a visual analogue craving scale every week. Urinary screening test for methamphetamine was carried out each week. The Beck Depression Inventory-II (BDI-II) was used to monitor participant depressive symptoms at baseline and bi-weekly during the treatment period.Results
At the end of the trial, the MPH-SR group was less methamphetamine positive compared to the placebo group and the difference was significant (p = 0.03). By the end of the study, MPH-SR group showed significantly less craving scores compared to the placebo group [MD (95% CI) = -10.28(0.88-19.18), t(54) = 2.19, p = 0.03]. There was greater improvement in the depressive symptoms scores in the intervention group compared to the placebo group [MD (95% CI) =2.03(0.31-3.75), t (54) =2.37, p = 0.02].Conclusion
Sustained-released methylphenidate was safe and well tolerated among active methamphetamine users and significantly reduced methamphetamine use, craving and depressive symptoms.Trial registration
IRCT201202281556N38 相似文献110.
Nafise Tabasi Mahmoud Mahmoudi Maryam Rastin Hamid Reza Sadeghnia Mojtaba HosseinPour Mashhadi Shahrzad Zamani Taghizade Rabe 《Food and Agricultural Immunology》2015,26(1):138-156
Renal cell carcinoma (RCC) is the most common renal malignancy in adults and exhibits highly intrinsic and acquired resistance to standard therapeutic strategies. We sought to determine the anti-cancer activity of hydroalcoholic extract of Nigella sativa seeds (NSE) and thymoquinone (TQ). Human renal cell carcinoma (ACHN) and fibroblast L929 cell lines were treated with NSE and TQ, and cytotoxicity was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) assay. Cell death pattern was determined by annexin V and propidium iodine (PI)-staining methods. Exposure to NSE, TQ and cisplatin significantly inhibited the growth of ACHN cells and showed significant increase of early apoptotic cells. Normal cells were more resistant to NSE and TQ-induced effects. The present study demonstrates that N. sativa and TQ exert anti-proliferative and pro-apoptotic effects on ACHN cells in a concentration and time-dependent manner, which suggests their potential to be used as a new therapeutic strategy for renal cancers. 相似文献