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41.
Demographics and health practices of 2,232 pregnant women in rural northeastern Ghana and characteristics of their 2,279 newborns were analyzed to determine benefits associated with intermittent preventive treatment (IPTp), antenatal care, and/or bed net use during pregnancy. More than half reported bed net use, 90% reported at least two antenatal care visits, and > 82% took at least one IPTp dose of sulfadoxine-pyrimethamine. Most used a bed net and IPTp (45%) or IPTp alone (38%). Low birth weight (< 2,500 grams) characterized 18.3% of the newborns and was significantly associated with female sex, Nankam ethnicity, first-born status, and multiple births. Among newborns of primigravidae, IPTp was associated with a significantly greater birth weight, significantly fewer low birth weight newborns, improved hemoglobin levels, and less anemia. Babies of multigravidae derived no benefit to birth weight or hemoglobin level from single or multiple doses of sulfadoxine-pyrimethamine during pregnancy. No differences or benefits were seen when a bed net was the only protective factor.  相似文献   
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BACKGROUND: Usefulness of sulfadoxine-pyrimethamine as first-line therapy for uncomplicated Plasmodium falciparum malaria and intermittent preventive treatment in pregnancy throughout sub-Saharan Africa is compromised by the spread of dhfr alleles associated with pyrimethamine resistance. A predominant haplotype associated with the N51I+C59R+S108N triple-mutant dhfr allele has been reported recently in 4 African countries. A more comprehensive picture of the evolution of this mutant allele in Africa is lacking. METHODS: Seventy-five P. falciparum isolates carrying the wild-type dhfr allele and 204 carrying the triple-mutant dhfr allele from 11 African countries were selected. The genetic diversity of the chromosomes bearing these alleles was analyzed with 4 microsatellite markers closely linked to the dhfr gene. RESULTS: Seventy-three different 4-locus haplotypes carrying the wild-type dhfr allele were found. By contrast, 175 (85%) of 204 isolates carrying the triple-mutant dhfr allele shared a unique haplotype, identical to the one identified in Thailand. For the remaining triple-mutant isolates and one isolate with the quadruple-mutant dhfr allele (N51I+C59R+S108N+I164L), haplotypes were closely related to the predominant haplotype by mutation or recombination. CONCLUSIONS: Migration of parasites carrying an ancestral triple-mutant dhfr allele drives the spread of dhfr alleles associated with pyrimethamine resistance throughout West and Central Africa.  相似文献   
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A total of 198 patients were treated with amodiaquine for uncomplicated malaria. Parasite clearance at day 14 was 85.4 and 48% at day 28.  相似文献   
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We evaluated prospectively, compliance with the Royal College of Obstetricians and Gynaecologists (RCOG) guidelines on termination of pregnancy (TOP) in a cohort of 340 women referred for termination of pregnancy in 2003 at South Tyneside Foundation Trust. The number of referrals represented one-fifth of all births in our unit during the study period. Teenagers were the largest single group of women requesting termination of pregnancy and the majority were nulliparous. There were 85 women who were seeking a repeat termination of pregnancy. The RCOG minimum referral standard was met in 80% of cases. A good number of women were unsure of their menstrual dates and only 5% had used emergency contraception. A total of 96% were either not using contraception, using condoms or taking oral contraceptives irregularly. A total of 50% of the women attended hospital without a Certificate A being completed by the referring practitioner. Surgical termination was preferred over medical termination in the cohort of women who could exercise a choice. It is possible to comply with the RCOG Termination of Pregnancy guidelines to a large extent in a District General Hospital, with some innovation. Close liaison between General Practitioners, Family Planning Clinics and Acute Hospitals is required. The adoption of agreed referral requirements and pathways would help in the delivery of a high quality service as advocated by the guideline.  相似文献   
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The disablement process model proposed by Nagi in 1965 and subsequently expanded by Verbrugge and Jette was used heuristically to study the relationships among morbidities and arm/shoulder function limitations that breast cancer survivors experience in the period following treatment. A telephone survey was administered to 148 patients (67%) from among 222 breast cancer survivors who had undergone surgery in 1997 and 1998. Sixty-three percent of respondents reported experiencing some numbness, while 35% noticed swelling. Between 13% and 15% reported moderate to severe pain. Similar proportions said the occurrence of pain ranged from intermittent to constant. Between 1% and 4% reported problems with shoulder abduction and flexion and a decrease in arm strength and daily use of the arm. Swellings in the torso and arm tended to cluster into two different factors. Numbness followed a similar pattern. Apart from numbness in the arm, all the other factors had strong significant associations with one another. In multiple regression analyses, current pain intensity and swelling in the arm were independently related to current functional status of the arm/shoulder. The results suggest that it may be feasible to use patients' self-reports to develop a simple lymphedema-specific tool to monitor the functional status of women living with or at risk for lymphedema. Such a tool, if properly designed and implemented, would allow for the timely introduction of lymphedema or pain management strategies to improve arm function and ultimately the quality of life of breast cancer survivors.  相似文献   
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BACKGROUND: The availability of genetic testing for cancer risk has prompted an examination of the intention of the general public to undergo testing. This study expands a previous psychosocial model of factors influencing intention to undergo genetic testing for cancer in general to the context of colon cancer. METHODS: A sample of 1,836 adult residents of Vermont, New Hampshire, and Maine were interviewed via telephone. The survey instrument included measures derived from the Health Belief Model and additional psychosocial measures adapted from the literature. Structural Equation Modeling techniques were used to examine factors associated with the likelihood to undergo genetic testing. RESULTS: Perceived barriers and benefits of testing, and perceived susceptibility to colon cancer had direct associations with likelihood. Optimism and pessimism had both direct and indirect effects. Age, socioeconomic status, family history, and awareness of genetic testing had indirect effects, and acted through the other factors. The model explained 22% of the variance in likelihood. CONCLUSIONS: Perceived barriers, benefits, susceptibility, optimism, and pessimism directly influenced likelihood, and may also mediate the effect of background factors examined in this study. These findings suggest effective educational strategies to improve decision-making concerning genetic testing for colon cancer risk in the general population.  相似文献   
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In areas of intense Plasmodium falciparum transmission, protective immunity is acquired during childhood in parallel with acquisition of agglutinating antibodies to parasite-encoded variant surface antigens (VSA) expressed on parasitized red blood cells. In a semi-immune child in such an area, clinical disease is caused mainly by parasites expressing VSA not recognized by preexisting VSA-specific antibodies in that child. Such malaria episodes are known to cause an increase in agglutinating antibodies specifically recognizing VSA expressed by the parasite isolate causing the illness, whereas antibody responses to other parasite isolates are relatively unaffected. However, the detailed kinetics of this VSA antibody acquisition are unknown and hence were the aim of this study. We show that P. falciparum malaria in Ghanaian children generally caused a rapid and sustained increase in variant-specific VSA antibody levels, while more transient and limited increases in levels of antibodies to VSA expressed by other parasite isolates were also seen. Plasma VSA antibody levels were positively correlated with the age of the healthy plasma donors but negatively correlated with the age of the parasite donors (the malaria patient). The data from this first detailed longitudinal study of acquisition of VSA antibodies support the hypothesis that naturally acquired protective immunity to P. falciparum malaria is mediated, at least in part, by VSA-specific antibodies.  相似文献   
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