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61.
Neonatal infection caused by adenovirus type 7   总被引:2,自引:0,他引:2  
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62.
Twenty-three adult female northern bobwhite (Colinus virginianus) quail were exposed to 0, 0.01, 0.1, and 1 mM ammonium perchlorate (AP) in drinking water for 30 d. Eggs laid in all treatment groups, including control, were collected, dated, given an identification number, and weighed. On day 30 of exposure, 10 birds were euthanized by carbon dioxide asphyxiation. Gross toxicological endpoints and thyroid histology were evaluated in 10 birds. Egg production and accumulation of perchlorate in the eggs (n = 10) and liver (n = 5) were determined. Perchlorate did not affect body or organ weights significantly; however, at 1 mM, AP caused alteration of thyroid gland morphology. Perchlorate did not affect egg production, but significant accumulation was observed in the eggs and livers of exposed birds.  相似文献   
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Specimens of Mytilus galloprovincialis were placed in bow nets and immersed at 3-10 m depth in a clean coastal region (reference area), Itea, and two marine stations along Gulf of Patras, N. Peloponnesus, Greece. One site is near the estuaries of the Glafkos River, which are influenced by local industrial and urban sources (Station 1); the second site, Agios Vasilios, has no evident organic pollution but is enriched in metals, particularly zinc (Station 2). One month after immersion, digestive glands were removed from the mussels and tested for lysosomal membrane stability, metallothionein content, and translational efficiency of ribosomes. In addition, gill cells were isolated and their micronuclei content was determined. Compared with the reference samples, mussels transplanted to Gulf of Patras showed a significant increased lysosomal membrane permeability and metallothionein content, reduced polysome levels, and increased chromosomal damage in relation to the contamination burden of each sampling area. Also, runoff ribosomes from mussels transplanted to Gulf of Patras (that is, ribosomes stripped of endogenous messengers and peptidyl- or/and aminoacyl-tRNAs) were less efficient at initiating protein synthesis in an in vitro-translation system than those prepared from reference samples. The whole set of data suggests that the degree of Gulf of Patras pollution differs between different sites and depends on the proximity of urban sewage and industrial outfalls. In addition, our results emphasize the importance of protein synthesis regulation as a component of the cellular stress response.  相似文献   
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Primary osteosarcoma of the bladder is an extremely rare type of tumour, and less than 30 adequately documented cases have been registered. From a clinical and radiological point of view, it is impossible to distinguish from other types of bladder tumours, since despite the fact that calcification of the bladder wall is common in osteosarcoma, other bladder diseases exist which may also present calcification. Prior to primary bladder osteosarcoma diagnosis, it is vital to first rule out the existence of an skeletal origin. Differential diagnosis must be carried out essentially with other bone-forming tumours, such as carcinosarcoma and transitional cell carcinoma with bone metaplasia. Prognosis for bladder osteosarcoma is extremely pessimistic, as the majority of patients do not survive beyond 6 months, regardless of the treatment carried out. We present a case of bladder osteosarcoma treated by right hemi-cystectomy, which remains disease free after a follow-up period of one year.  相似文献   
65.
Enhanced short-term plasmid transfection of filtration surgery tissues   总被引:9,自引:0,他引:9  
PURPOSE: To quantify and localize plasmid transfection of filtration surgery tissues using two delivery techniques. METHODS: Full-thickness filtering procedures were performed on eyes of New Zealand albino rabbits. In 10 eyes, naked plasmid DNA in saline was either injected beneath Tenon's capsule at the filtration site or absorbed into a collagen shield that was then placed external to the sclerostomy and under the Tenon's capsule. Forty-eight hours after surgery, levels of the reporter gene, chloramphenicol acetyltransferase (CAT) were measured in samples of ocular tissues. In two additional eyes, the ss-galactosidase (ss-GAL:) reporter gene expression was localized histologically. RESULTS: Injection of plasmid DNA in saline vehicle into the filtration bleb produced readily detectable CAT activity in bleb tissue (conjunctiva, Tenon's capsule, and sclera) whereas CAT activity was nearly undetectable in samples of the cornea, iris-ciliary body, and tissues located opposite the bleb site. Delivery of the plasmid DNA into the bleb through a collagen shield increased CAT activity 30-fold over injection of plasmid in saline (2711 +/- 567 mU/mg versus 92 +/- 38 mU/mg). ss-Gal activity was imaged only in the region of the bleb, and microscopic examination showed ss-Gal activity localized to Tenon's capsule fibroblasts, with minimal ss-Gal activity observed in inflammatory cells or scleral fibroblasts. CONCLUSIONS: Transfection of filtration tissues is enhanced by absorption of naked DNA into a collagen shield. Furthermore, transfection is localized to the fibroblasts and inflammatory cells of the filtration bleb site. Gene therapy using naked plasmid DNA and a simple collagen shield delivery vehicle may be useful for regulating wound healing after glaucoma surgery.  相似文献   
66.
Unlike traditional approaches to sexuality and HIV education which can be constrained by the sensitive nature of the subject, Information Technology (IT) can be an innovative teaching tool that can be used to educate people about HIV. This is especially relevant to interventions targeting young people; the population group fond of using IT, and the same group that is more vulnerable to HIV/AIDS. Yet, there are significantly few empirical studies that rigorously evaluated computer-assisted school-based HIV/AIDS interventions in developing countries. The modest studies conducted in this area have largely been conducted in developed countries, leaving little known about the effectiveness of such interventions in low resource settings, which moreover host the majority of HIV/AIDS infections.This research addresses this gap by conducting a controlled pre-post intervention evaluation of the impacts of the World Starts With Me (WSWM), a computer-assisted HIV/AIDS intervention implemented in schools in Uganda. The research question was: did the WSWM intervention significantly influence students’ sexual behaviors, HIV/AIDS knowledge, attitudes and self-efficacy? To address this question, questionnaires were simultaneously administering to 146 students in an intervention group (the group receiving the WSWM intervention) and 146 students in a comparison group (the group who did not receive the WSWM intervention), before (February 2009) and after the intervention (December 2009).Findings indicate that the intervention significantly improved students’ HIV/AIDS knowledge, attitudes self-efficacy, sex abstinence and fidelity, but had no significant impact on condom use. The major reason for non-use of condoms was lack of knowledge about condom use which can be attributed to teachers’ failure and inabilities to demonstrate condom use in class. To address this challenge, intervention teachers should be continuously trained in skills-based and interactive sexuality education. This training will equip them with self-confidence and interactive teaching skills, including tactics for emphasizing building students’ skills through role plays and interactive assignments. In addition, the HIV interventions themselves should include interactive virtual condom use demonstrations that can be accessed by students themselves.  相似文献   
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Antibiotic-resistant pathogens are increasingly prevalent in the hospitals and community. A timely and accurate diagnosis of the infection would greatly help physicians effectively treat patients. In this research we investigate the potential of using neural networks (NN) and logistic regression (LR) approach in diagnosing methicillin-resistant Staphylococcus aureus (MRSA). Receiver-Operating Characteristic (ROC) curve and the cross-validation method are used to compare the performances of both systems. We found that NN is better than the logistic regression approach, in terms of both the discriminatory power and the robustness. With modeling flexibility inherent in its techniques, NN is effective in dealing with MRSA and other classification problems involving large numbers of variables and interaction complexity. On the other hand, logistic regression in our case is slightly inferior, offers more clarity and less perplexity. It could be a method of choice when fewer variables are involved and/or justification of the results is desired. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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