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The authors evaluated comparatively the results of surgical treatment of mitral stenosis in 203 patients after open mitral commissurotomy (OMC) (their personal experience) and the literature data concerning 168 patients who underwent closed mitral commissurotomy (CMC). The frequency of mitral stenosis recurrences with the use of both methods was determined. OMC was on a par with CMC in safety and exceeded it in efficacy. The frequency of mitral restenosis was considerably lower after OMC than after CMC (p less than 0.05). The authors claim that the main cause of mitral stenosis recurrences is residual stenosis developing in inadequate correction of the anomaly, while the principal preventive measure is OMC which makes it possible to separate the fused commissures completely, remove the subvalvar adhesions, and restore the mobility of the cusps.  相似文献   
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This paper describes the tragic case of a young woman who died of cancer of the colon after successfully donating eggs to her younger sister. Although there is no direct link between her operation and the subsequent development of bowel carcinoma, this case imparts a feeling of unease when seen in conjunction with other cases reported during the last few years. It is a reminder that little is known of the long-term consequences of some aspects of assisted conception. Women undergoing ovarian stimulation for themselves or a matched recipient have the right to be advised, in an agreed format, that there is some concern about unproven potential risks from the stimulatory drugs. The safety of egg donors must assume priority over all other considerations, including lack of donors or any moral position. The recent decision by the Human Fertilisation and Embryology Authority (HFEA) to withdraw any form of payment or recompense to egg donors does not seem to us to be based on a balance of scientific advances, patient needs and the ethics of gamete supply. They state that the intention to withdraw payments was implicit in the 1990 Human Fertilisation and Embryology (HFE) Act. However the Act was based on the Warnock report made 6 years earlier. Even in 1990 ovum donation was uncommon and fertility drugs had not yet caused any unease. The Act provided the HFEA with discretionary powers to issue directions so that the future policies would be consistent with any emerging new medical evidence. It is imperative that the HFEA provide convincing evidence on how the current policy of payment to donors harms society, donors or recipients, and how in the UK the new policy will improve medical practice in assisted conception. Successful pilot studies must precede the implementation of any new policy. Failure to do this could cause irreversible harm to the practice of assisted conception using donor gametes, which will ultimately be against the basic aims of the 1990 HFE Act.   相似文献   
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The effects of cell extracts and supernatants ofLactobacillus spp. andCorynebacterium spp. on catalase activity and growth ofStaphylococcus aureus 6538 P were studied. Intra- and extracellular metabolites of lactobacilli and corynebacteria inhibited catalase activity ofS. aureus 6538 P. The growth ofS. aureus 6538 P decreased after incubation with lactobacillus metabolites. The inhibitory effect of intra- and extracellular metabolites of lactobacilli and corynebacteria on catalase activity ofS. aureus is a possible pathway of microbial interrelations responsible for the formation and/or development of microbial biocenoses. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130, No. 7, pp. 80–82, July, 2000  相似文献   
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Introduction  

This report describes the isolation and characterization of three new murine mammary epithelial cell lines derived from mammary tumors from MMTV (mouse mammary tumor virus)/activated Neu + TβRII-AS (transforming growth factor [TGF]-β type II receptor antisense RNA) bigenic mice (BRI-JM01 and BRI-JM05 cell lines) and MMTV/activated Neu transgenic mice (BRI-JM04 cell line).  相似文献   
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OBJECTIVE: To assess the antibody response to influenza vaccine of children vertically infected with HIV. DESIGN: Prospective study in HIV infected children vaccinated during the winter of 1994-5. SETTING: Family HIV clinic at St Mary's Hospital, Paddington. SUBJECTS: 25 children, aged 1-11 years, vertically infected with HIV. MAIN OUTCOME MEASURES: Responses to influenza antigens (H1N1-A/Taiwan/1/86, H3N2-A/Shandong/9/93, B/Panama/45/ 90) were tested by haemagglutination inhibition. Antibody responses were assessed according to clinical symptoms and immune function, stratified according to the 1994 revised classification for HIV infection in children. RESULTS: 23 children (92%) had either very low or no detectable antibody before vaccination. New protective antibody responses were made by 10 children (40%): in seven to a single antigen, in two to two antigens, and in one to all three antigens. For each antigen there was an overall small increase in the mean geometric titre of antibody produced, but this only reached a protective level for antigen H1N1 and for children with minimal symptoms. Less symptomatic children were significantly more likely to produce a protective antibody response to influenza vaccination. No association was found between immune function, as measured by CD4 count, and vaccine response. CONCLUSIONS: Only vaccination of the least symptomatic HIV infected children against influenza is likely to be effective. This will not only protect them against influenza, but will also protect other more immunosuppressed and vulnerable members of their families.  相似文献   
8.
Horne  MK d; Rosse  WF; Flickinger  EG; Saltzman  HA 《Blood》1975,45(3):365-375
The "early-labeled" peak (ELP) of 14CO excretion following injection of glycine-2-14C was used to study erythropoiesis in a patient with sideroblastic anemia and in four subjects with myeloproliferative disorders. The ELP was greatly enlarged in all patients, as compared with a normal volunteer. The contour of the peaks from the hematologically abnormal subjects suggested the presence of increased erythroid heme degradation. In the patient with sideroblastic anemia, all hours of the early peak were significantly reduced after transfusion. This was interpreted to mean that even the earliest or "nonerythroid" phase of the peak is influenced by erythropoietic activity, at least under conditions of erythropoietic stress.  相似文献   
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Experimental modeling of the emergence of virulent Vibrio cholerae El Tor genovariants is presented. It has been shown that the obtained genovariants differed neither in phenotypic or genotypic traits from natural genetically altered strains that emerged in populations of wild-type strains. It has been established, using the PCR and sequencing methods, that the genovariants formed in the process of conjugation carried in their genome a fragment of the CTXClassφ prophage genome with the ctxB1 gene of classical-type cholera vibrios. It has been shown that changes in the prophage’s structure led to higher levels of toxigenicity and virulence in the genovariants compared to a typical recipient strain. A proteomic analysis has also revealed changes in the expression of 26 proteins performing various functions in the cell, such as metabolism, energy exchange, transport of amino acids, etc.). These data are indicative of the effect produced by the new DNA region in the genome of the genovariants on the expression level of some house-keeping genes. The obtained results confirm the idea that horizontal gene transfer is one of the mechanisms leading to the emergence of genovariants in the populations of wild-type strains.  相似文献   
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