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1.
BACKGROUND: Scleroderma renal crisis is one of the most life threatening complications of scleroderma. Enteric hyperoxaluria complicates extensive disease or resection of the small intestine in the presence of an intact colon, and is associated with calcium oxalate nephrolithiasis. This cause of renal failure may be underestimated and should be considered in all patients with malabsorption and renal failure. CASE REPORT: A 78 year old woman with systemic sclerosis affecting the bowel developed acute renal failure caused by oxalate nephropathy. RESULTS: The patient's renal failure improved on an oxalate free diet.  相似文献   
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3.

Background

Elephantorrhiza elephantina (Ee) and Pentanisia prunelloides (Pp) are two medicinal plants which are widely used to remedy various ailments including diarrhoea, dysentery, inflammation, fever, rheumatism, heartburn, tuberculosis, haemorrhoids, skin diseases, perforated peptic ulcers and sore joints in southern Africa (South Africa, Swaziland, Botswana and Zimbabwe). The following study was conducted to explore the in vitro cytotoxicity, antioxidant properties and phytochemical profile of the two medicinal plants.

Materials and Methods

The cytotoxicity of the aqueous and methanol extracts and fractions of both species was studied using the brine shrimp lethality tests (BST) for the first time.

Results

The results demonstrated that the lethality (LC50) for crude extracts for both plants ranged between 1.8 and 5.8 ppm and was relatively greater than that for the methanol, ethyl acetate and chloroform fractions of the extracts which ranged between 2.1 ppm and 27 ppm. This suggested that crude extracts were more potent than their respective fractions, further explaining that the different fractions of phytochemicals in these plant species work jointly (in synergy) to exert their therapeutic efficacy. Both aqueous and methanol extracts of the two medicinal plants demonstrated a high degree of antioxidant capacity against the DPPH radical with the Duh and Yen inhibition percentage ranging between 4.5% and 72%. Phytochemical studies of the rhizome extracts showed that the major compounds present include flavonoids, tannins, anthocyanidins, anthraquinones, triterpenoids (oleanolic acid), the steroidal saponin Diosgenin, the sugars, rhamnose, glucuronic acid, Arabinose and hexoses.

Conclusion

This is the first report of the detection and isolation of diosgenin and oleanolic acid from the rhizome extracts of Ee and Pp. All structures were determined using spectroscopic/spectrometric techniques (1H NMR and 13C and LC-ESI-MS) and by comparison with literature data.  相似文献   
4.
Regulatory CD4+CD25+Foxp3+ T cells (Tregs) play an important role in the induction of allospecific tolerance. However tolerance in solid organ transplantation by mere transfer of Tregs has been difficult. Besides this the stability of the differentiation phenotype of Tregs has recently been questioned. We therefore aimed in generating large numbers of stable allospecific Tregs from naïve T cells by retroviral transduction with Foxp3. These were tested in an immunogenic skin transplantation model (C57BL/6→BALB/c). We established a system of transduction of mouse T cells with ecotropic retroviruses expressing Foxp3 and Thy1.1 as a surface marker to follow up transduced T cells. Alloantigen‐specific Tregs were generated by stimulating naïve recipient CD4+ T cells with irradiated donor splenocytes. CD25+ and/or CD69+ allospecific recipient CD4+ T cells were isolated and transduced with Foxp3. Alloantigen‐specific Foxp3 T cells (iTregs) showed high expression for the Treg markers Foxp3, CTLA4 and GITR. They could suppress a MLR in an alloantigen‐specific manner. Furthermore, they could be expanded up to 18 fold in vitro while maintaining their Treg phenotype and expression of lymph node homing markers like CCR7 and CD62L. iTregs prevented skin graft rejection without the need for chronic immunosuppression and recipients showed systemic allospecific allotolerance. Alloantigen‐specific Tregs were far more potent than polyspecific Tregs. Mechanisms of tolerance were graft specific homing, expansion and long‐term persistence of Tregs within the graft (>100 days, 90% of intragraft Tregs were alloantigen‐specific). In fact, tolerance could be transferred with re‐transplantation of the tolerant graft onto secondary recipients. Third party grafts were readily rejected demonstrating specificity of tolerance. Due to the Foxp3 transduction, iTregs did not lose their Treg phenotype. The results prove that large numbers of stable alloantigen‐specific Tregs can be generated from a polyclonal repertoire of naïve T cells. This is the first time that allotolerance was achieved in a non‐lymphopenic transplant model using skin grafts in an immunogenic strain combination. Therefore, antigen‐specific Tregs might have a huge therapeutic potential after solid organ transplantation.  相似文献   
5.
This study explored the experiences and perceptions of sexuality and HIV/AIDS among 15–24 year-old young people with physical disabilities in a South African Township characterised by high unemployment rates and lack of social services. Ten young people and ten parents participated in multiple individual interviews as well as in focus group discussions. The analysis of audio taped and transcribed responses identified common experiences and perceptions among participants. The results indicate that disabled young people have limited factual knowledge about sexuality and HIV/AIDS. The decisions and choices they make about sexual behaviour are not informed by what they know; rather, they are part of the whole life situation in Nyanga. Their need to be loved and accepted, need for job security and family life, were more important than practicing ‘safe sex’. Therefore, there is need for HIV/AIDS programme developers to take into account the experiences and perceptions of the target population.In this paper the phrases ‘young people with physical disabilities’ and disabled young people’ are used interchangeably.  相似文献   
6.
A total of sixty samples of bottled water processed in Zimbabwe by three companies, were analysed microbiologically, to assess the relative safety of locally processed bottled water. The samples were from different batches and from different storage conditions and the analyses were for total viable counts and coliforms. Four (6.7%) and seven (11.7%) samples were found to exceed the recommended maximum total viable and coliform counts, respectively. There was a low incidence of Staphylococus aureus (3.3%), Pseudomonas species (6.7%) and Bacillus species (5%). Overall, the work shows that locally bottled water is generally safe, microbiologically, though it is necessary to continue with precautionary measures because any lapse in hygiene may lead to microbial proliferation.  相似文献   
7.
It is now recognized that acquiring specific skills in self-evaluation helps students in a more general appraisal of their overall performance. Self- and peer-evaluation skills are essential prerequisites for the success of every doctor in maintaining professional competence. In the Faculty of Medicine and Health Sciences (FMHS) of the United Arab Emirates, problem-based learning (PBL) is instituted in the first year. Self-evaluation by students and tutor rating of students' performances are an integral part of the PBL tutorials. This has provided the opportunity to conduct a systematic study of the role of self-evaluation by students as distinct from the tutor evaluation of students in the PBL tutorials for five themes. The study sample included all preparatory year (first-year) students who joined the FMHS in 1994 and 1995. A total number of 64 students participated, of whom 17 (26%) were male and 47 (74%) female. Mean self-evaluation scores were high throughout the module and did not follow any trend from theme one to theme five. While self and tutor scores were similar, male student self-evaluation scores were higher than for female students on overall scores. The sharing of assessment reports between students and tutors has been perceived to be a useful tool for the students' development of the skills of analysis, differentiation and critical appraisal.  相似文献   
8.
The authors used state-of-the-art concept mapping approaches to examine structural institutional effects of church and secular high schools on the types of sexual and HIV-prevention education messages transmitted to learners in Zimbabwe. Participants were school teachers (n = 26), school counselors (n = 28), and pastors involved in student pastoral care (n = 14; males = 27, females = 41). They reported on messages perceived to influence sexual decisions of learners in their school setting. The self-report data were clustered into message types using concept mapping and contrasted for consistency of content and structure both between and within type of school. The authors also engaged in curriculum document study with member checks in the participant schools to determine convergence of the evidence on school-type effects of the messages transmitted to students. Church schools prioritized faith-informed sexual and HIV-prevention messages, whereas both types of schools prioritized Life skills education and a future focus. Secular schools prioritized sex and HIV messages in the context of community norms. Facts about HIV and AIDS were relatively underemphasized by church schools. The implicit knowledge values that differentiate types of schools influence learner access to information important for their sexual decisions.  相似文献   
9.
Where problem-based learning (PBL) is the main method used in medical curricula, the literature suggests that it is crucial that the problems used are effective in facilitating students to identify relevant learning issues. These learning issues guide the students' studying. The present investigation explores the extent to which students identify relevant issues following exposure to prepared paper problems. In the preparatory year, in an Introduction to Medicine module, four groups of students were exposed to six themes (Health Care System, Environment and Health, Alternative and Islamic Medicine, Chronic Illness, Infectious Diseases, and Prevention and Health Promotion). Each group had two facilitators per theme. Having discussed the prepared problems, the students identified learning issues which were collected for the purpose of the study. Two content experts, using a Likert scale, analysed learning issues for their concordance to staff objectives per theme. Kappa coefficients were computed for the six PBL themes in order to assess inter-rater agreement. Learning issues identified as having no relationship to theme objectives were further analysed for their relevance to theme objectives. No objective was totally omitted by any student group. There was a 100% concordance of objectives to learning issues demonstrated over four themes. The relationship of learning issues to theme objectives ranged from 55–85% in the theme on health care system, and 73–94% in the theme on environment and health. Irrelevant learning issues were identified in the first two PBL themes addressed. Kappa coefficients over the six PBL themes varied from 0·49 to 0·82.  相似文献   
10.
Anopheline mosquitoes were studied in an area of Zimbabwe to correlate their population densities with seasonality in malaria incidence. Four trapping methods were employed for adult mosquitoes: pit traps, outdoor and indoor man-baited nets and a sheep-baited net. Anopheles funestus exhibited two population peaks during the year, one in March and the other in September/October. The following over-all proportions of the An. gambiae complex were recorded: An. gambiae Giles (2.5%), An. arabiensis Patton (14.3%) and An. guadriannulatus Theobald (83.2%). Peak populations were observed in March, with most An. gambiae and An. arabiensis preferring outdoor man-baited nets. Approximately equal preference for outdoor nets and pit traps was observed for An. guadriannulatus, which was the only species present throughout the year. The implications of these findings for malaria transmission, which showed a peak in April, and the suitability of the sampling methods employed are discussed.  相似文献   
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