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31.
32.
Surveillance cultures and duration of carriage of multidrug-resistant Acinetobacter baumannii 下载免费PDF全文
Marchaim D Navon-Venezia S Schwartz D Tarabeia J Fefer I Schwaber MJ Carmeli Y 《Journal of clinical microbiology》2007,45(5):1551-1555
Isolating carriers of multidrug-resistant (MDR) Acinetobacter baumannii is the main measure to prevent its spread. Identification of carriers accompanied by contact precautions is essential. We aimed to determine the appropriate surveillance sampling sites and the duration of carriage of MDR A. baumannii. We studied prospectively two groups of patients from whom MDR A. baumannii was previously isolated: (i) those with recent clinical isolation (or=6 months). Screening for carriage was conducted from six sites: nostrils, pharynx, skin, rectum, wounds, and endotracheal aspirates. Strains recovered concurrently from different sites were genotyped using pulsed-field gel electrophoresis. Twelve of 22 with recent clinical isolation of MDR A. baumannii had >or=1 positive screening culture, resulting in a sensitivity of 55% when six body sites were sampled. Sensitivities of single sites ranged from 13.5% to 29%. Among 30 patients with remote clinical isolation, screening cultures were positive in 5 (17%), with a mean duration of 17.5 months from the last clinical culture. Remote carriers had positive screening cultures from the skin and pharynx but not from nose, rectum, wounds, or endotracheal aspirates. Eleven strains from five patients were genotyped. In all but one case, isolates from different sites in a given patient were clonal. Current methodology is suboptimal to detect MDR A. baumannii carriage. The sensitivity of surveillance cultures is low, even when six different body sites are sampled. The proportion of individuals with previous MDR A. baumannii isolation who remain carriers for prolonged periods is substantial. These data should be considered when designing measures to limit the spread of MDR A. baumannii. 相似文献
33.
Yahya Khosravi Ahmad Salimi Jalal Pourahmad 《Xenobiotica; the fate of foreign compounds in biological systems》2018,48(8):860-866
1. Today, diamond nanoparticles have several industrial applications. Nano diamond (ND) as a carbon allotrope diffuses in the air easily during producing and processing procedures.2. In this study, we investigated sub-acute exposed to ND at the exposure chamber in mice. The animals were divided into two groups (control and exposed group to ND at the concentration of 3?µg/m3 for 3?h/day, 5?days/week for 30?days) in a whole-body inhalation chamber.3. Our results showed that exposure to ND induced the hematological and biochemical changes. The target organs for ND were the lungs, brain and heart in the mice, respectively. Also, ND increased reactive oxygen species (ROS) generation, lipid peroxidation (LPO), the collapse of mitochondrial membrane potential (MMP), decreased a level of reduced glutathione (GSH) and finally increased a level of glutathione disulfide (GSSG) in lung, brain and heart tissues. Our results suggest that exposure to ND can induce oxidative stress in the tissue mentioned.4. These results suggest that exposure of researchers and workers with diamond nanoparticles probably increase a risk of respiratory, cardiovascular and cerebral disorders through oxidative stress. However, good ventilation, appropriate personal protective equipment and using of anti-oxidant compounds in daily diet of worker are suggested. 相似文献
34.
Mohammad Mahdi Majzoobi Seyyed Hamid Hashemi Mojgan Mamani Fariba Keramat Jalal Poorolajal Hamid Reza Ghasemi Basir 《International journal of antimicrobial agents》2018,51(3):365-369
Brucellosis is associated with a high recurrence rate and requires more than one course of standard treatment; therefore, more research is required to find more effective treatments that lead to prompt recovery, and reduce the relapse of disease. This single-blind, randomized study was designed to evaluate the effect of the standard treatment for brucellosis in combination with hydroxychloroquine.A total of 177 patients with acute brucellosis were randomly assigned to one of two treatment groups: doxycycline-streptomycin (DS) and doxycycline-streptomycin-hydroxychloroquine (DSH). Clinical symptoms and signs, serological tests, and side effects of therapy were compared between the two groups during the treatment course and at three and six months after the end of drug therapy. Of the 177 patients, with a mean age of 40.5?±?16.9 years, 66.1% were males. The mean duration of clinical signs prior to admission was 43.4?±?41.1 days. Appropriate clinical responses, relapse, treatment failure, and adverse drug reactions were seen in 98.9%, 1.2%, 0.0%, and 12.6% of patients, respectively, in the DSH group vs. 86.7%, 11.6%, 2.3%, and 19.8% of patients, respectively, in the DS group. There were significant differences in clinical response and relapse rates between the two groups. The addition of hydroxychloroquine to a doxycycline-streptomycin regimen appears to increase the efficacy of treatment, accelerate improvement of clinical symptoms, and significantly reduce the rate of relapse of brucellosis. 相似文献
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36.
Charles F. McTiernan Penelope Morel Leslie T. Cooper Navin Rajagopalan Vinay Thohan Mark Zucker John Boehmer Biykem Bozkurt Paul Mather John Thornton Jalal K. Ghali Karen Hanley-Yanez James Fett Indrani Halder Dennis M. McNamara 《Journal of cardiac failure》2018,24(1):33-42
Objective
The aim of this work was to evaluate the hypothesis that the distribution of circulating immune cell subsets, or their activation state, is significantly different between peripartum cardiomyopathy (PPCM) and healthy postpartum (HP) women.Background
PPCM is a major cause of maternal morbidity and mortality, and an immune-mediated etiology has been hypothesized. Cellular immunity, altered in pregnancy and the peripartum period, has been proposed to play a role in PPCM pathogenesis.Methods
The Investigation of Pregnancy-Associated Cardiomyopathy (IPAC) study enrolled 100 women presenting with a left ventricular ejection fraction of <0.45 within 2 months of delivery. Peripheral T-cell subsets, natural killer (NK) cells, and cellular activation markers were assessed by flow cytometry in PPCM women early (<6 wk), 2 months, and 6 months postpartum and compared with those of HP women and women with non–pregnancy-associated recent-onset cardiomyopathy (ROCM).Results
Entry NK cell levels (CD3–CD56+CD16+; reported as % of CD3– cells) were significantly (P?<?.0003) reduced in PPCM (6.6?±?4.9% of CD3– cells) compared to HP (11.9?±?5%). Of T-cell subtypes, CD3+CD4–CD8–CD38+ cells differed significantly (P?<?.004) between PPCM (24.5?±?12.5% of CD3+CD4–CD8– cells) and HP (12.5?±?6.4%). PPCM patients demonstrated a rapid recovery of NK and CD3+CD4–CD8–CD38+ cell levels. However, black women had a delayed recovery of NK cells. A similar reduction of NK cells was observed in women with ROCM.Conclusions
Compared with HP control women, early postpartum PPCM women show significantly reduced NK cells, and higher CD3+CD4–CD8–CD38+ cells, which both normalize over time postpartum. The mechanistic role of NK cells and “double negative” (CD4–CD8–) T regulatory cells in PPCM requires further investigation. 相似文献37.
Perfluorooctanoic acid (PFOA) is an octanoic acid and is found in wildlife and humans. We have investigated mitochondrial toxicity in isolated mitochondria from, placenta, brain, liver, and heart after oral exposure with PFOA in mice during gestational days (7‐15). Histopathological examination and mitochondrial toxicity parameters were assayed. Results indicated that PFOA decreased the weight of the fetus and placenta, the length of the fetus and the diameter of the placenta, dead fetuses and dead macerated fetuses in treated mice with 25 mg/kg. Histopathological examination showed that PFOA induced pathological abnormalities in liver, brain, heart, and placenta. Also, PFOA induced mitochondria toxicity in brain, liver, heart of mouse fetus. Our results indicate that PFOA up to 20 mg/kg exposure adversely affect embryofetal/developmental because for mitochondria dysfunction. These results suggested that mitochondrial dysfunction induced by PFOA in liver, heart, and brain lead to developmental toxicity and abnormality in tissues. 相似文献
38.
Objective:
Enterobacter cowanii is a genus of common gram-negative, facultatively anaerobic, rod-shaped, non-spore-forming bacterium of the Enterobacteriaceae family. This organism can be potentially a powdered infant milk formula-borne opportunistic pathogen. The aim of this study was to isolate and identify E. cowanii from consumed powdered infant formula milk (PIF) in intensive care units (NICU) and to determine antimicrobial susceptibility patterns of this bacterium.
Methods:
E. cowanii was isolated according to FDA method in 125 samples of PIF milk purchased from drug stores between Jun 2011 and March 2012. For final confirmation, biochemical tests embedded in API-20E system were used. The drug susceptibility test was performed using the disc diffusion method according to CLSI recommendations.
Findings
: Out of the 125 PIF samples investigated, 4 (3.2%) samples were positive for E. cowanii. All four isolates from PIF samples were uniformly susceptible to imipenem, meropenem, ceftazidime, ciprofloxacin, and colistin. Fifty percent of isolates were resistant to ampicillin, amoxicillin, and cotrimoxazole
Conclusion: Analysis of the results indicated that complementary studies are necessary to clarify the possible role of E. cowanii as a food contaminant, in common NICU infections and high risk groups including persons with underlying disease and immunocompromised individuals.Key Words: Powdered Infant Formula Milk; Neonatal Intensive Care Unit; E. Cowanii; Antimicrobial Susceptibility 相似文献
39.
40.
Jack L. Spurbeck Alan R. Zinsmeister Kevin J. Meyer Syed M. Jalal 《American journal of medical genetics. Part A》1996,61(4):387-393
Consistency of optimum chromosome spreading during harvest of cytogenetic specimens remains a major concern. We have tested the idea that a precise control of the drying rate (the time with which metaphase cells dry), as fixed cell suspension is placed on a slide or an in situ culture in last fixation, may be the answer. Amniocyte and lymphocyte cultures were allowed to dry at defined combinations of relative humidity (RH) and temperature (T) in a modified Thermotron environmental control unit. We were able to demonstrate, based on 2,250 amniocytes and 1,650 lymphocytes, that the metaphase area after drying was a function of RH and T for both in situ and non-in situ culture systems. As the RH and T increase, the metaphase area increases until a threshold is reached. Also, as RH increases, the slide drying time increases. Data obtained using a response surface regression, proportional hazards regression analysis and slide drying time studies are consistent with our model of chromosome spreading. Optimum metaphase areas can be achieved at various combinations of RH and T. We propose that the use of an environmental control unit is a practical way of achieving optimum chromosome spreading routinely and in a highly consistent manner. © 1996 Wiley-Liss, Inc. 相似文献