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521.
Background
Risks for methicillin‐resistant Staphylococcus aureus (MRSA) among those with HIV infection have been found to vary, and the epidemiology of USA‐300 community‐acquired (CA) MRSA has not been adequately described.Methods
We conducted a retrospective review of HIV‐infected out‐patients from January 2002 to December 2007 and employed multivariate logistic regression (MLR) to identify risks for MRSA colonization or infection. Pulsed‐field gel electrophoresis (PFGE) was used to identify USA‐300 strains. Results Seventy‐two (8%) of 900 HIV‐infected patients were colonized or infected with MRSA. MLR identified antibiotic exposure within the past year [odds ratio (OR) 3.4; 95% confidence interval (CI) 1.5–7.7] and nadir CD4 count <200 cells/μL (OR 2.5; 95% CI 1.2–5.3) as risks for MRSA colonization or infection. Receipt of antiretroviral therapy (ART) within the past year was associated with decreased risk (OR 0.16; 95% CI 0.07–0.4). Eighty‐nine percent of available strains were USA‐300. MLR identified skin or soft tissue infection (SSTI) as the only predictor for infection with USA‐300 (OR 5.9; 95% CI 1.4–24.3). Conclusion Significant risks for MRSA among HIV‐infected patients were CD4 count nadir <200 cells/μL and antibiotic exposure. Only the presence of an SSTI was associated with having USA‐300, and thus the use of patient characteristics to predict those with USA‐300 was limited. In addition, ART within the previous year significantly reduced the risk of MRSA colonization or infection.522.
Objective: The aim of this study was to determine frequency and distribution of dental caries in an early medieval Avar population from Central Europe, namely Vienna.
Methods: The evaluation of caries was carried out in an anthropological sample consisting of the remains of 136 individuals and included 2215 permanent teeth. Age and sex estimations were based on dental development and on skeletal ageing methods. The presence of dental caries was determined according to clinical aspects using a dental probe.
Results: The frequency of ante mortem tooth loss in the sample was 23.8%; the total caries frequency was calculated as 14.9%. The highest caries rate was recorded in the second mandibular molar (34.6%). The most affected tooth surface was found to be the root with 12.7%, followed by the approximal surface with 8.6%, but only 7.7% of the occlusal surfaces were affected by caries.
Conclusion: This study revealed that Avars suffered from higher caries rates than most other medieval European populations, but experienced a similar dental caries distribution. Attrition of the occlusal surface resulting from a diet containing abrasive particles with accompanying posteruptive tooth movement is considered the major factor causing this premodern caries pattern. 相似文献
Methods: The evaluation of caries was carried out in an anthropological sample consisting of the remains of 136 individuals and included 2215 permanent teeth. Age and sex estimations were based on dental development and on skeletal ageing methods. The presence of dental caries was determined according to clinical aspects using a dental probe.
Results: The frequency of ante mortem tooth loss in the sample was 23.8%; the total caries frequency was calculated as 14.9%. The highest caries rate was recorded in the second mandibular molar (34.6%). The most affected tooth surface was found to be the root with 12.7%, followed by the approximal surface with 8.6%, but only 7.7% of the occlusal surfaces were affected by caries.
Conclusion: This study revealed that Avars suffered from higher caries rates than most other medieval European populations, but experienced a similar dental caries distribution. Attrition of the occlusal surface resulting from a diet containing abrasive particles with accompanying posteruptive tooth movement is considered the major factor causing this premodern caries pattern. 相似文献
523.
The neonatal period of liver development is an often overlooked phase of development. For instance, ontogeny of xenobiotic-metabolizing enzymes can markedly affect biotransformation as the liver matures. To systematically examine the ontogenic gene expression patterns of cytochrome P450 genes (P450) in mice, the gene expression profiles of 19 xenobiotic-metabolizing P450 in Cyp1 to 4 families were determined. The mRNA levels in C57BL/6 mouse livers were quantified using branched DNA technology at the following ages: gestational day 17 (2 days before birth) and postnatal days 0, 1, 3, 5, 10, 15, 20, 30, and 45. Among the 13 P450 genes expressed in mouse livers, three distinct ontogenic expression patterns were identified by cluster analysis. Genes in group 1 (Cyp3a16 as well as 3a41b in male) were expressed in the perinatal period, but they were essentially nondetectable by 30 days of age. Genes in group 2 (Cyp2e1, 3a11, and 4a10 as well as 3a41b in female) quickly increased after birth and reached maximal expression levels by day 5. Genes in group 3 (Cyp1a2, 2a4, 2b10, 2c29, 2d22, 2f2, 3a13, and 3a25) were expressed at low levels until days 10 to 15, but they markedly increased at day 20 to a high and stable level. In conclusion, the developmental expression of P450 in mouse liver can be divided into three patterns, suggesting that different mechanisms are responsible for the expression of P450 during liver maturation. 相似文献
524.
Ela WP Sedlak DL Barlaz MA Henry HF Muir DC Swackhamer DL Weber EJ Arnold RG Ferguson PL Field JA Furlong ET Giesy JP Halden RU Henry T Hites RA Hornbuckle KC Howard PH Luthy RG Meyer AK Sáez AE Vom Saal FS Vulpe CD Wiesner MR 《Environmental health perspectives》2011,119(1):6-10
Background
This commentary evolved from a workshop sponsored by the National Institute of Environmental Health Sciences titled “Superfund Contaminants: The Next Generation” held in Tucson, Arizona, in August 2009. All the authors were workshop participants.Objectives
Our aim was to initiate a dynamic, adaptable process for identifying contaminants of emerging concern (CECs) that are likely to be found in future hazardous waste sites, and to identify the gaps in primary research that cause uncertainty in determining future hazardous waste site contaminants.Discussion
Superfund-relevant CECs can be characterized by specific attributes: They are persistent, bioaccumulative, toxic, occur in large quantities, and have localized accumulation with a likelihood of exposure. Although still under development and incompletely applied, methods to quantify these attributes can assist in winnowing down the list of candidates from the universe of potential CECs. Unfortunately, significant research gaps exist in detection and quantification, environmental fate and transport, health and risk assessment, and site exploration and remediation for CECs. Addressing these gaps is prerequisite to a preventive approach to generating and managing hazardous waste sites.Conclusions
A need exists for a carefully considered and orchestrated expansion of programmatic and research efforts to identify, evaluate, and manage CECs of hazardous waste site relevance, including developing an evolving list of priority CECs, intensifying the identification and monitoring of likely sites of present or future accumulation of CECs, and implementing efforts that focus on a holistic approach to prevention. 相似文献525.
AA da Silva L Bingle PM Speight CD Bingle T Mauad LFF da Silva PA Vargas 《Oral diseases》2011,17(3):258-264
Oral Diseases (2011) 17 , 258–264 Objective: To analyse and compare the expression of Palate, Lung, and Nasal Epithelium Clone (PLUNC) proteins in salivary glands from patients with and without AIDS (control group) using autopsy material. Methods: We analysed the expression of PLUNCs using immunohistochemistry in parotid (n = 45), submandibular (n = 47) and sublingual gland (n = 37) samples of AIDS patients [30 with normal histology, 21 with mycobacteriosis, 14 with cytomegalovirus (CMV) infection, 30 with chronic non‐specific sialadenitis, and 30 HIV‐negative controls. In situ hybridization (ISH) for SPLUNC 2 in the HIV‐negative group was performed. Results: SPLUNC 1 expression was detected in the mucous acini of submandibular and sublingual glands, and SPLUNC 2 were seen in the serous cells. LPLUNC 1 expression was only positive in the salivary ducts. There was a higher expression of SPLUNC 2 in AIDS patients with CMV infection and mycobacteriosis when compared with all other groups. The intensity of staining for SPLUNC 2 was greater around the lesions than the peripheral ones. ISH for SPLUNC 2 showed perinuclear positivity in the serous cells in all HIV‐negative cases. Conclusions: SPLUNC 1 and LPLUNC 1 proteins were similarly expressed in the salivary glands of AIDS patients and non‐HIV patients. CMV infection and mycobacteriosis increase SPLUNC 2 expression in serous cells in the salivary gland of AIDS patients. 相似文献
526.
Mary-Powel Thomas BA Gabriela Ammann MPH CD Chinelo Onyebeke MPH Tanya K. Gomez MPH Samantha Lobis MPH Wenhui Li PhD Mary Huynh PhD 《分娩》2023,50(1):138-150