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41.
42.
Relationship Between Peer Victimization and Posttraumatic Stress Among Primary School Children 下载免费PDF全文
Leib Litman Giuseppe Costantino Richard Waxman Caribel Sanabria‐Velez Von Marie Rodriguez‐Guzman Anabelle Lampon‐Velez Richard Brown Tomas Cruz 《Journal of traumatic stress》2015,28(4):348-354
Peer victimization is a common stressor experienced by children. Although peer victimization has been studied extensively, few studies have examined the potential link between peer victimization and posttraumatic stress disorder (PTSD), and no studies of which we are aware have examined this link among children in primary school. The paucity of studies examining the link between PTSD and peer victimization in primary school is surprising because peer victimization occurs more frequently and is more likely to be physical among 7‐ and 8‐year‐old children. This study assessed the relationship between peer victimization and PTSD in a sample of 358 elementary school children (ages 6–11 years). Results indicated that peer victimization accounted for 14.1% of PTSD symptom severity among boys and 10.1% among girls. Additionally, we found gender differences in the types of peer victimization that were most associated with PTSD symptom severity (d = 0.38). The long‐term developmental consequences that may be associated with peer victimization‐linked PTSD symptomatology are discussed. 相似文献
43.
R B Tesh J Lubroth H Guzman 《The American journal of tropical medicine and hygiene》1992,47(5):574-581
A series of experiments were done to study the effect of simulated summer and winter temperatures on the development of Phlebotomus perniciosus (Diptera:Psychodidae) and on the survival of Toscana virus in transovarially infected insects. Sand flies maintained at 28 degrees C developed relatively fast, with adults emerging from 40 to 55 days after initial oviposition. Similar results were obtained with insects reared at 25 degrees C. In contrast, sand flies maintained at 15 degrees C developed slowly up to the fourth larval instar; at that point, further development ceased and the insects entered diapause. Diapause could be terminated by increasing the ambient temperature to 25 degrees C. The ambient temperatures at which the immature forms were reared (15 degrees C, 25 degrees C, and 28 degrees C) had no effect on the subsequent F1 adult filial infection rates with Toscana virus (49.1%, 47.5%, and 46.5%, respectively). The results of these experiments provide a model of how Toscana virus survives the winter in endemic areas by maintenance in diapausing P. perniciosus larvae. In another experiment, venereal transmission of Toscana virus was shown from transovarially infected males to non-infected virgin females. This is the first demonstration of sexual transmission of a phlebovirus by sand flies. If venereal transmission occurs in nature, it would provide an alternative method of virus amplification in the vector population, in the absence of viremic vertebrates. 相似文献
44.
Kim R. Blasdell Hilda Guzman Steven G. Widen Cadhla Firth Thomas G. Wood Edward C. Holmes Robert B. Tesh Nikos Vasilakis Peter J. Walker 《The American journal of tropical medicine and hygiene》2015,92(2):405-410
The Le Dantec serogroup of rhabdoviruses comprises Le Dantec virus from a human with encephalitis and Keuriliba virus from rodents, each isolated in Senegal. The Kern Canyon serogroup comprises a loosely connected set of rhabdoviruses many of which have been isolated from bats, including Kern Canyon virus from California, Nkolbisson virus from Cameroon, Central African Republic, and Cote d''Ivoire, Kolente virus from Guinea, Mount Elgon bat and Fikirini viruses from Kenya, and Oita virus from Japan. Fukuoka virus isolated from mosquitoes, midges, and cattle in Japan, Barur virus from a rodent in India and Nishimuro virus from pigs in Japan have also been linked genetically or serologically to this group. Here, we analyze the genome sequences and phylogenetic relationships of this set of viruses. We show that they form three subgroups within a monophyletic group, which we propose should constitute the new genus Ledantevirus. 相似文献
45.
Tae-Hyun Yoo Christopher E. Pedigo Johanna Guzman Mayrin Correa-Medina Changli Wei Rodrigo Villarreal Alla Mitrofanova Farah Leclercq Christian Faul Jing Li Matthias Kretzler Robert G. Nelson Markku Lehto Carol Forsblom Per-Henrik Groop Jochen Reiser George William Burke Alessia Fornoni Sandra Merscher 《Journal of the American Society of Nephrology : JASN》2015,26(1):133-147
Diabetic kidney disease (DKD) is the most common cause of ESRD in the United States. Podocyte injury is an important feature of DKD that is likely to be caused by circulating factors other than glucose. Soluble urokinase plasminogen activator receptor (suPAR) is a circulating factor found to be elevated in the serum of patients with FSGS and causes podocyte αVβ3 integrin-dependent migration in vitro. Furthermore, αVβ3 integrin activation occurs in association with decreased podocyte-specific expression of acid sphingomyelinase-like phosphodiesterase 3b (SMPDL3b) in kidney biopsy specimens from patients with FSGS. However, whether suPAR-dependent αVβ3 integrin activation occurs in diseases other than FSGS and whether there is a direct link between circulating suPAR levels and SMPDL3b expression in podocytes remain to be established. Our data indicate that serum suPAR levels are also elevated in patients with DKD. However, unlike in FSGS, SMPDL3b expression was increased in glomeruli from patients with DKD and DKD sera-treated human podocytes, where it prevented αVβ3 integrin activation by its interaction with suPAR and led to increased RhoA activity, rendering podocytes more susceptible to apoptosis. In vivo, inhibition of acid sphingomyelinase reduced proteinuria in experimental DKD but not FSGS, indicating that SMPDL3b expression levels determined the podocyte injury phenotype. These observations suggest that SMPDL3b may be an important modulator of podocyte function by shifting suPAR-mediated podocyte injury from a migratory phenotype to an apoptotic phenotype and that it represents a novel therapeutic glomerular disease target. 相似文献
46.
Cotler SJ Hay N Xie H Chen ML Xu PZ Layden TJ Guzman G 《Digestive diseases and sciences》2008,53(3):844-849
Activation of the Akt-mTORC1 signaling pathway was evaluated in premalignant and hepatocellular carcinoma (HCC) lesions by
assessing the expression of pS6, an Akt effector, and PTEN, an Akt suppressor. Methods: Immunohistochemical staining for pS6 and PTEN was performed on liver tissue from 52 patients with cirrhosis, with and without
HCC. Two pathologists independently evaluated pS6 staining on a semiquantitative scale and categorized PTEN staining as present
or absent. Results: In the HCC group, pS6 staining was greatest in HCC, followed by dysplasia, and benign cirrhotic tissue (P < 0.001). pS6 staining was greater in cirrhotic tissue from patients with HCC compared to cirrhosis in patients without HCC
(P = 0.03). PTEN staining in tumor was absent in 8/33 (24%) cases. Loss of PTEN expression was more common in patients with
higher tumor stage, compared to those with stage 1 tumors (P = 0.04). Conclusion: Immunohistochemical evidence of activation of the Akt-mTORC1 pathway is associated with HCC. 相似文献
47.
Jenice Ria S. Guzman‐Clark Meika A. Fang Mary E. Sehl Laural Traylor Theodore J. Hahn 《Arthritis care & research》2007,57(1):140-146
Objective
To determine present practice for the management of glucocorticoid‐induced osteoporosis (GIOP) in veterans; to characterize provider knowledge, beliefs, and practice behaviors regarding management of GIOP; and to identify potential barriers and interventions in the management of GIOP.Methods
To characterize current management of GIOP in an academic veterans administration medical center, we conducted a retrospective chart review of 100 patients who were prescribed a 90‐day supply of prednisone. To assess clinicians' knowledge of GIOP clinical guidelines and perceptions of GIOP management, primary care clinicians and subspecialists completed a questionnaire and participated in focus groups.Results
Chart review revealed that only 32 of 100 patients receiving long‐term glucocorticoid treatment underwent bone mineral density testing, and only 32 patients were prescribed the recommended calcium supplements. Of the 23 providers who completed the questionnaire and participated in the focus groups, 4 correctly identified both the dose and duration of glucocorticoid use at which GIOP prevention measures should be instituted. Common GIOP management barriers cited by participants were lack of knowledge, having limited time during the clinic visit to address all problems, patient nonadherence, and system problems. The most commonly mentioned potential interventions were the use of computerized clinical reminders and patient education.Conclusion
Clinicians frequently do not follow recommended guidelines for the management of GIOP. Improving the management of GIOP will likely require a fundamental redesigning of care processes for this disorder in order to overcome provider, patient‐related, and system barriers. 相似文献48.
Tesh RB Guzman H da Rosa AP Vasconcelos PF Dias LB Bunnell JE Zhang H Xiao SY 《The Journal of infectious diseases》2001,183(10):1431-1436
This report describes the clinical laboratory findings in golden hamsters experimentally infected with yellow fever (YF) virus. An accompanying paper describes the pathologic findings. Following intraperitoneal inoculation of a virulent strain of YF virus, hamsters developed a high-titered viremia (up to 109/mL) lasting 5--6 days and abnormal liver function tests. YF hemagglutination-inhibiting antibodies appeared 4 or 5 days after infection, often while viremia was still present. The mortality rate in YF-infected hamsters was variable, depending on the virus strain and the age of the animals. Clinical and pathologic changes in the infected hamsters were very similar to those described in experimentally infected macaques and in fatal human cases of YF, which indicates that the golden hamster may be an excellent alternative animal model, in place of nonhuman primates, for research on the pathogenesis and treatment of YF and other viscerotropic flavivirus diseases. 相似文献
49.
Atherosclerosis and omega-3 fatty acids in the populations of a fishing village and a farming village in Japan 总被引:2,自引:0,他引:2
Yamada T Strong JP Ishii T Ueno T Koyama M Wagayama H Shimizu A Sakai T Malcom GT Guzman MA 《Atherosclerosis》2000,153(2):469-481
The effect of different dietary habits on atherosclerosis was investigated by examining the content of ordinary diets and relevant risk factors through a mass health survey on two village populations in Japan. In total, 261 inhabitants in the fishing village and 209 in the farming village were examined for body build, blood pressure, and blood chemistry. Information on smoking habits and food consumption was obtained using a semi-quantitative item-frequency questionnaire. Pulse wave velocity of the aorta, intima-media thickness of the carotid artery, and atherosclerotic plaques as obtained by ultrasonography were used as measures of atherosclerosis. All measures of atherosclerosis are lower in the fishing village than in the farming village in both men and women. There is a striking 5-8-fold difference in the number of atherosclerotic plaques (P < 0.0001) between the populations. The observed differences in atherosclerosis parallels differences in dietary habits and differences in the serum essential fatty acids. Evaluation of the omega-3 fatty acids over the combined populations reveals a negative association with the number of plaques in the common carotid while the omega-6 fatty acids shows a weak positive association with plaques. 相似文献
50.
Marco A Costa Steven Shoemaker Hideki Futamatsu Chris Klassen Dominick J Angiolillo Minh Nguyen Alan Siuciak Paul Gilmore Martin M Zenni Luis Guzman Theodore A Bass Norbert Wilke 《Journal of the American College of Cardiology》2007,50(6):514-522
OBJECTIVES: To evaluate the ability of quantitative perfusion cardiac magnetic resonance (CMR) to assess the hemodynamic significance of coronary artery disease (CAD) compared with well-established anatomic and physiologic techniques. BACKGROUND: Fractional flow reserve (FFR) is considered by many investigators to be a reliable stenosis-specific method to determine hemodynamically significant CAD. Quantitative perfusion CMR is a promising noninvasive approach to detect CAD but has yet to be validated against FFR. METHODS: This is a prospective study in patients with suspected CAD who underwent coronary angiography, FFR, and CMR assessments. The quantitative myocardial perfusion reserve (MPR) was calculated in 720 myocardial sectors (8 sectors/slice). The MPR was calculated from the ratio between stress and rest myocardial flow based on signal intensity time curves using deconvolution analysis. Stress was simulated with adenosine for both FFR and MPR. The MPR assessments were compared to FFR (n = 44 coronary segments) and quantitative coronary angiography (n = 108 segments) in the corresponding coronary territories. RESULTS: The MPR was 1.54 +/- 0.36 in segments with FFR < or =0.75 (n = 14) and 2.11 +/- 0.68 in those with FFR >0.75 (n = 30; p = 0.0054). An MPR cutoff of 2.04 was 92.9% (95% CI 77.9 to 100.0) sensitive and 56.7% (95% CI 32.8 to 80.6) specific in predicting a coronary segment with FFR < or =0.75. The MPR was 1.54 +/- 0.49 in coronary segments with > or =50% diameter stenosis (DS) (n = 47) and 2.13 +/- 0.80 in segments with <50% DS (n = 61; p < 0.001). An MPR cutoff of 2.04 was 85.1% (95% CI 71.1 to 99.2) sensitive and 49.2% (95% CI 33.6 to 64.8) specific in predicting CAD with > or =50% DS. CONCLUSIONS: Quantitative perfusion CMR is a safe noninvasive test that represents a stenosis-specific alternative to determine the hemodynamic significance of CAD. 相似文献