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1.
Choleraphage φ149 DNA is a linear double-stranded molecule 69 × 106 Da or 104 kilobase pairs (kbp). From restriction enzyme analysis, it has been concluded that the DNA is circularly permuted. There are at least three S1 nuclease-sensitive sites along the length of the molecule. These sites represent single-strand interruptions repairable by T4 DNA ligase. A physical map of the DNA has been constructed using the restriction endonucleases BamH1 and BglII.  相似文献   
2.
OBJECTIVE: Over 3% of infants born annually in the United States are from a multiple gestation pregnancy, yet there is little data published about the feeding practices of their mothers. The objectives of this study were to determine and compare the rates of breast milk feeding of mothers of multiples and mothers of singletons. METHODS: Stratified random sampling (n = 686) on the basis of plurality of pregnancy and gestational age at delivery was performed on a 1999 birth certificate database in the greater Cincinnati area. We collected information about infant feeding during the first 6 months of life using a retrospective, self-administered questionnaire and phone interview from mothers of term singletons (TS), preterm singletons (PS), term multiples (TM), and preterm multiples (PM). Data were analyzed using chi-square and logistic or multiple regression. RESULTS: We obtained feeding information from 346 mothers (n = 81 TS, 80 PS, 90 TM, and 95 PM). By 3 days postpartum, PM provided breast milk less often than all other groups: TS = 69%, PS = 66%, TM = 73%, PM = 57% (P =.035). Among mothers who initiated breast milk feeding, the geometric mean duration of at least some breast milk feeding was significantly shorter for PM than for all other groups: TS = 23 weeks, PS = 19 weeks, TM = 24 weeks, and PM = 12 weeks (P =.002). CONCLUSIONS: Further evaluation of the potential causes for the lower breast milk feeding rates among PM is needed to develop effective intervention strategies and increase the number of preterm multiple gestation infants receiving breast milk.  相似文献   
3.

Background

In India, multidrug-resistant tuberculosis (MDR-TB) patients are usually treated in hospitals. Decentralised care model, however, has been suggested as a possible alternative by the World Health Organization (WHO). In the “End TB Strategy”, the WHO highlights, as one of the key targets for 2035, that ‘no TB-affected families should face catastrophic hardship due to the tuberculosis’. Removal of financial barriers to health-care access and mitigation of catastrophic expenditures are therefore considered vital to achieve the universal health coverage (UHC) goal. Since forgoing healthcare due to the financial constraints is a known fact in India, decentralised care as an intervention choice (as against hospital-based care) might enhance equity provided it is an affordable choice. Thus, an economic evaluation was conducted, from the perspective of the national health system in India, to assess the cost-effectiveness of decentralised care compared to centralised care for MDR-TB.

Methods

This study uses a decision-analytic model with a follow-up of two years to assess the expected costs of the decentralised versus the centralised approaches for MDR-TB treatment. A published systematic review of observational studies yielded the MDR-TB treatment outcomes, which included treatment success, treatment default, treatment failure, and mortality parameters. It was observed that these parameters did not vary significantly between the two alternatives. Treatment costs included the following costs: hospital admission costs, clinic costs, visits to laboratory and MDR-TB centre, drug therapy, injections and food. Costs data of drugs, diagnosis, hospital stay and travel to public facilities, based on a simple market survey, were taken from a recently published study on MDR-TB expenditures in the Chhattisgarh state of India. Potential cost savings related to the implementation of decentralised MDR-TB care for all patients who initiated MDR-TB treatment in India were additionally estimated.

Results

Estimated average expected total treatment cost was US$ 3390.56 for the hospital-based model and US$ 1724.1 for the decentralised model for a patient treated for MDR-TB in India, generating potential savings of US$1666.50 per case, with ICER US$ 2382.68 per QALY gained. One of the primary drivers of this difference was the significantly more intensive (thus expensive) stay charges in the hospital. If the costs and treatment probabilities are extrapolated to the whole country, with 48114 MDR-TB patients initiated on treatment in 2017, decentralised care would have additional 1058 patients cured, gain additional 3824 QALYs, and avert 2165 deaths, as compared to centralised care, in India. At various scenarios of coverage rates of decentralised and centralised care the cost difference would range between 23% and 94% for the country.

Conclusion

Our study provides evidence of cost savings for MDR-TB patients if patients choose decentralised treatment in comparison to suggested hospitalisation of these patients for centralised treatment with similar outcomes. The economic evaluation presented in this study expected significant efficiency gains in choice of two treatment options and the cost savings may improve equity. In India, treatment of MDR-TB using decentralised care is expected to result in similar patient outcomes at markedly reduced public health costs compared with centralised care.  相似文献   
4.
In this paper, we developed a high-performance solid-state pH sensor using a Ce0.9Sr0.1(Zr0.53Ti0.47)O4 (CSZT) membrane through a very simple sol–gel spin-coating process. The structural properties of the CSZT membrane are correlated with its sensing characteristics. The CSZT based EIS sensor exhibited a high pH sensitivity of 92.48 mV pH−1, which is beyond the Nernst limit (59.4 mV pH−1), and good reliability in terms of a low hysteresis voltage of 1 mV and a small drift rate of 0.15 mV h−1. This behaviour is attributed to the incorporation of Sr in the CSZT sensing membrane, which promotes change in the Ce oxidation state from Ce4+ to Ce3+.

We developed a high-performance solid-state pH sensor using a Ce0.9Sr0.1(Zr0.53Ti0.47)O4 (CSZT) membrane through a very simple sol–gel spin-coating process.  相似文献   
5.
Hemodialysis vascular access is at the same time both the “Lifeline” and the “Achilles Heel” of hemodialysis. This review will initially summarize the vascular biology of dialysis vascular access dysfunction and then use this information to describe some novel and innovative ways (including advances in the process of care for vascular access) to prevent this problem.  相似文献   
6.

Background

Helicobacter pylori (H. pylori) has been etiologically linked with primary gastric lymphoma (PGL) and gastric carcinoma (GC). There are a few reports of occurrence of both diseases in the same patient with H. pylori infection.

Case presentation

We report a patient with PGL in whom the tumor regressed after surgical resection combined with eradication of H. pylori infection. However, he developed GC on follow up; this was temporally associated with recrudescence / re-infection of H. pylori. This is perhaps first report of such occurrence.

Conclusions

Possible cause and effect relationship between H. pylori infection and both PGL and GC is discussed. This case also documents a unique problem in management of PGL in tropical countries where re-infection with H. pylori is supposed to be high.
  相似文献   
7.
8.
Hemodialysis vascular access dysfunction is a major cause of morbidity and hospitalization in the hemodialysis population at a cost of over 1 billion dollars per annum. Venous stenosis and thrombosis as a result of venous neointimal hyperplasia are the major causes of hemodialysis vascular access dysfunction. Despite the magnitude of the clinical problem, there are currently no effective therapies for this condition. We believe that this could be because of an inadequate understanding of the pathogenesis of this condition. At a histological level, venous neointimal hyperplasia (both in human specimens and in a pig model) is characterized by the presence of smooth muscle cells/myofibroblasts, microvessel formation (angiogenesis), and the accumulation of extracellular matrix components, all of which could be potential targets for therapeutic intervention. In particular, polytetrafluoroethylene dialysis access grafts could be the ideal clinical model for testing out novel local therapies to block neointimal hyperplasia. The current review describes the lesion of venous neointimal hyperplasia in human samples and in a pig model and suggests possible future directions for the development of effective local therapies for this condition.  相似文献   
9.
At the round the clock entergency of the Deparment of Otorhinolaryngology, Medical College, Kolkata, different types of cases are managed everyday. The various emergency conditions encountered by us in last four years are gathered and analyzed in this study. The different problems and their modes of management are discussed here.  相似文献   
10.
PURPOSE: There are a significant number of patients with asymptomatic hormone-resistant prostate cancer who have increasing prostate-specific antigen (PSA) levels but little or no evaluable disease. The immunogenicity and minimal toxicity associated with cell-based vaccine therapy makes this approach attractive for these patients. EXPERIMENTAL DESIGN: We have evaluated a vaccine comprising monthly intradermal injection of three irradiated allogeneic prostate cell lines (8 x 10(6) cells each) over 1 year. The first two doses were supplemented with bacille Calmette-Guérin as vaccine adjuvant. Twenty-eight hormone-resistant prostate cancer patients were enrolled. Patients were assessed clinically and PSA levels were measured monthly. Radiologic scans (X-ray, computed tomography, and bone scan) were taken at baseline and at intervals throughout the treatment period. Comprehensive monthly immunologic monitoring was undertaken including proliferation studies, activation markers, cytokine protein expression, and gene copy number. This longitudinal data was analyzed through predictive modeling using artificial neural network feed-forward/back-propagation algorithms with multilayer perceptron architecture.RESULTS: Eleven of the 26 patients showed statistically significant, prolonged decreases in their PSA velocity (PSAV). None experienced any significant toxicity. Median time to disease progression was 58 weeks, compared with recent studies of other agents and historical control values of around 28 weeks. PSAV-responding patients showed a titratable T(H)1 cytokine release profile in response to restimulation with a vaccine lysate, while nonresponders showed a mixed T(H)1 and T(H)2 response. Furthermore, immunologic profile correlated with PSAV response by artificial neural network analysis. We found predictive power not only in expression of cytokines after maximal stimulation with phorbol 12-myristate 13-acetate, but also the method of analysis (qPCR measurement of IFN-gamma > qPCR measurement tumor necrosis factor-alpha > protein expression of IFN-gamma > protein expression of interleukin 2). CONCLUSIONS: Whole cell allogeneic vaccination in hormone-resistant prostate cancer is nontoxic and improves the natural history of the disease. Longitudinal changes in immunologic function in vaccinated patients may be better interpreted through predictive modeling using tools such as the artificial neural network rather than periodic "snapshot" readouts.  相似文献   
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