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101.
102.
Previous studies of the effects of early undernutrition on behavior in adult rats have confounded underfeeding with maternal deprivation or membership in a large litter. In the present experiment food-deprived rats received full-time maternal care and lived in the same-sized litters as well-fed controls. In contrast to previous findings food-deprived animals in the present study did not differ from controls in the open-field test, in a test of motor coordination, and in 2 learning tasks. However, food-deprived animals were more active than controls in a residential plus maze. Females showed less effect of food deprivation on body growth, but a much greater effect on activity, than males. These findings suggest that early undernutrition when not confounded with social and maternal deprivation may have more restricted effects on adult behavior than has been previously believed.  相似文献   
103.
The nebulization of amphotericin B desoxycholate (AMB-DOC), liposomal amphotericin B (L-AMB), amphotericin B lipid complex (ABLC) and amphotericin B colloidal dispersion (ABCD) has been investigated. Particle sizes of generated aerosol droplets were measured. Pulmonary amphotericin B deposition and amphotericin B concentration in blood directly after nebulization and at six weeks after nebulization was measured in healthy rats. The efficacy of nebulized amphotericin B formulations was evaluated in persistently granulocytopenic rats with invasive pulmonary aspergillosis. Treatment was given either after or before fungal inoculation. The endpoint was survival of animals. Aerosol particle sizes, expressed as the values for the mass median diameter were 1.38, 2.43, 0.90 and 2.29 microm for AMB-DOC, L-AMB, ABLC and ABCD, respectively. Amphotericin B concentrations in the lungs directly after nebulization exceeded the minimum inhibitory concentration of Aspergillus fumigatus and amphotericin B was still detected in lungs of rats at six weeks after nebulization. Treatment, started at 16 h after fungal inoculation, resulted in a significantly prolonged survival as compared with sham-treated rats for all four formulations. Prophylactic treatment at one week before fungal inoculation resulted in a significantly prolonged survival for all four formulations. Aerosol treatment given at two weeks before inoculation was effective only for AMB-DOC and L-AMB, whereas treatment given at six weeks resulted in a significantly prolonged survival for L-AMB only. All commercially available amphotericin B preparations could be nebulized efficiently and may be of value in the prophylactic treatment of invasive pulmonary aspergillosis.  相似文献   
104.
The primary objective of this paper is to investigate the effect of adherence to prescribed antiretroviral therapy on virologic response measured repeatedly over time in HIV-infected patients. To this end observations on plasma viral load (HIV RNA) assessed in copies/ml are categorized into four clinically meaningful states, [0--50[, [50--400[, [400--2000[, [2000 and up. A time-dependent continuation ratio model is used to analyse longitudinal ordinal responses. The main challenge lies in modelling dependencies over time and using information contained in the data efficiently to establish a dynamic relation between observed patient adherence and viral load. Among the several measures of adherence investigated, two specifically account for long periods of time without intake. One is derived from the third moment of the inter-dose interval distribution, while the second reflects internal drug exposure using pharmacokinetic parameters. The approach is applied to a clinical trial involving 35 patients who were followed over 12 months. Results demonstrate a significant relation between patient adherence and virologic response.  相似文献   
105.
Potent liposomal PorA formulations containing various lipopolysaccharide (LPS) derivatives were developed. The following adjuvants were compared: the commonly used aluminum phosphate (AlPO(4)), and three LPS like adjuvants: monophosphoryl lipid A (MPL), lipopolysaccharide (galE LPS) and the less toxic LPS mutant lpxL1. The immunogenicity in mice was evaluated and compared with that against an outer membrane vesicle (OMV) vaccine. The IgG isotype distribution and bactericidal activity were determined. Furthermore, PorA specific proliferation of lymph node cells after immunization and restimulation in vitro was studied with selected formulations. Both AlPO(4) and MPL were unable to improve the functional immunogenicity (i.e. bactericidal response) of liposomal PorA. Besides, when these adjuvants were used, the percentage of responders in the groups did not reach 100%. This was also observed with non adjuvated PorA-liposomes or OMV. Of the adjuvants studied, only galE LPS and lpxL1 LPS were capable of increasing the immunogenicity and avoid non responsiveness against PorA-liposomes. Importantly, the adjuvant activity of lpxL1 LPS was accompanied by an improved PorA specific proliferation of lymph node cells and a concomitant increase in IL-2 production. In conclusion and considering its lower toxicity, lpxL1 LPS adjuvated liposomes are superior to other formulations tested.  相似文献   
106.
PURPOSE: The way babies and young children are reared is important to their health and development. Extensive breast-feeding has also been shown to reduce the development of artificial sucking habits like digit or pacifier-sucking. The aim of this study was to determine feeding methods, artificial sucking habits, and the presence of malocclusions in 3-year-old girls living in different regions of the world. METHODS: Children from the following countries were involved in the present study: (1) Brazil (Porto Alegre); (2) Japan (Niigata); (3) Mexico (Mexico City); (4) Norway (Oslo); (5) Sweden (Falk?ping); (6) Turkey (Istanbul); (7) and the United States (Iowa City, Iowa). During the interview and examination, the following variables were evaluated and registered: (1) breastfeeding and bottle-feeding; (2) duration and frequency; (3) sucking habits; (4) posterior and anterior crossbites; and (5) other malocclusions/normal occlusion. RESULTS: The prevalence of breast-feeding was very high in all groups, ranging between 78% and 98%. The prevalence of bottle-feeding in the different areas was also high. Except for Iowa City, the prevalence of digit-sucking was relatively low. Pacifier-sucking is fairly popular in most areas, with the exception of Niigata. The prevalence of normal occlusion in different cities ranged from 38% to 98%. CONCLUSIONS: There are considerable differences in feeding, as well as artificial sucking habits, in different areas of the world and at different periods.  相似文献   
107.
Minor histocompatibility antigens (mHAgs) selectively expressed by cells or cell subsets of the hematopoietic system are targets of the T cell-mediated graft-versus-leukemia response that develops following allogeneic hematopoietic stem cell transplantation (HSCT) for the treatment of hematological malignancies. This observation has served as the rationale for utilizing mHAg-specific immunotherapy for the treatment of particular patients. However, at present, only a select and small number of patients could potentially benefit from mHAg-based immunotherapy. A report from de Rijke et al. in this issue of the JCI describes a new hematopoietic lineage-specific HLA-B7-restricted mHAg associated with remission of chronic myeloid leukemia. This result represents another example of an mHAg-mediated graft-versus-leukemia response, thereby expanding the number of patients eligible for mHAg-based immunotherapy in the setting of HSCT.  相似文献   
108.
The breast cancer resistance protein (BCRP/ABCG2) is an ATP-binding cassette drug efflux transporter that extrudes xenotoxins from cells, mediating drug resistance and affecting the pharmacological behavior of many compounds. To study the interaction of human wild-type BCRP with steroid drugs, hormones, and the dietary carcinogen 2-amino-1-methyl-6-phenylimidazo(4,5-b)pyridine (PhIP), we expressed human BCRP in the murine MEF3.8 fibroblast cell line, which lacks Mdr1a/1b P-glycoprotein and Mrp1, and in the polarized epithelial MDCKII cell line. We show that PhIP was efficiently transported by human BCRP in MDCKII-BCRP cells, as was found previously for murine Bcrp1. Furthermore, we show that six out of nine glucocorticoid drugs, corticosterone, and digoxin increased the accumulation of mitoxantrone in the MEF3.8-BCRP cell line, indicating inhibition of BCRP. In contrast, aldosterone and ursodeoxycholic acid had no significant effect on BCRP. The four most efficiently reversing glucocorticoid drugs (beclomethasone, 6alpha-methylprednisolone, dexamethasone, and triamcinolone) and 17beta-estradiol showed a significantly reduced BCRP-mediated transepithelial transport of PhIP by MDCKII-BCRP cells, with the highest reduction of PhIP transport ratio for beclomethasone (from 25.0 +/- 1.1 to 2.7 +/- 0.0). None of the tested endogenous steroids or synthetic glucocorticoids or digoxin, however, were transported substrates of BCRP. We also identified the H(2)-receptor antagonist drug cimetidine as a novel efficiently transported substrate for human BCRP and mouse Bcrp1. The generated BCRP-expressing cell lines thus provide valuable tools to study pharmacological and toxicological interactions mediated by BCRP and to identify new BCRP substrates.  相似文献   
109.
We present an extensive characterization of 10 B-cell lymphomas with a t(9;14)(p13;q32). The presence of the PAX5/IGH gene rearrangement was demonstrated by fluorescence in situ hybridization (FISH) using a validated probe set, whereas complex karyotypic changes were reassessed by multiplex-FISH (M-FISH). Pathologic and clinical review revealed the presence of this rearrangement in 4 histiocyte-rich, T-cell-rich B-cell lymphomas (HRTR-BCLs) and 2 posttransplantation diffuse large B-cell lymphomas (PTLD-DLBCLs). In contrast to initial observations describing this translocation in lymphoplasmacytic lymphoma (LPL) and LPL-derived large B-cell lymphoma, our data showed a wide morphologic and clinical spectrum associated with the PAX5/IGH rearrangement, pointing to an association between this aberration and a subset of de novo DLBCLs presenting with advanced disease and adverse prognosis. In addition, the recurrent incidence of this rearrangement in both HRTR-BCL (4 cases) and PTLD-DLBCL (2 cases) was previously unrecognized and is intriguing.  相似文献   
110.
Mucocutaneous leishmaniasis (MCL) is an important health problem in many rural areas of Latin America, but there are few data on the results of programmatic approaches to control the disease. We report the results of a control programme in San Martin de Pangoa District, which reports one of the highest prevalences of MCL in Peru. For 2 years (2001--2002), the technicians at the health post were trained in patient case management, received medical support and were supplied with antimonials. An evaluation after 2 years showed the following main achievements: better diagnosis of patients, who were confirmed by microscopy in 34% (82/240) of the cases in 2001 and 60% of the cases (153/254) in 2002; improved follow-up during treatment: 237 of 263 (90%) patients who initiated an antimonial therapy ended the full treatment course; improved follow-up after treatment: 143 of 237 (60%) patients who ended their full treatment were correctly monitored during the required period of 6 (cutaneous cases) or 12 (mucosal cases) months after the end of treatment. These achievements were largely due to the human and logistical resources made available, the constant availability of medications and the close collaboration between the Ministry of Health, a national research institute and an international non-governmental organization. At the end of this period, the health authorities decided to register a generic brand of sodium stibogluconate, which is now in use. This should allow the treatment of a significant number of additional patients, while saving money to invest in other facets of the case management.  相似文献   
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