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21.
BACKGROUND: Two types of OA are distinguished: immunological (OA with sensitization) and non-immunological, i.e., irritant induced asthma or reactive airways dysfunction syndrome (RADS). METHODS: We describe the case of a worker who developed respiratory symptoms after a spill of diphenylmethane diisocyanate (MDI) at the workplace. RADS was initially diagnosed and the worker resumed working. The progressive worsening of symptoms and the appearance of symptoms-work relationship one year later, when concentrations of isocyanates were no longer "irritant," suggested immunological OA. RESULTS: The diagnosis was confirmed by specific inhalation challenge test, followed by removal from exposure and complete recovery. CONCLUSIONS: In the case of RADS due to an agent with both irritant and sensitizing properties, history should be repeatedly assessed for a possible symptom-work relationship. If this is found, further investigations should be carried out, including specific inhalation challenges, to confirm the possibility of immunological OA. 相似文献
22.
Stanzial AM Benoni G Cuzzolin L Gabrielli GB Pasino M Perfetti P Corrocher R 《Journal of chemotherapy (Florence, Italy)》2003,15(6):584-590
In this study we tried to elucidate the role of nitric oxide (NO) in chronic hepatitis C in relation to antioxidant status, since the mechanisms by which hepatitis C virus (HCV) causes cell damage and the factors underlying its resistance to therapy are not well understood. Before and after one and six months of therapy with alpha-interferon and ribavirin, we measured nitrite/nitrate urinary levels, total antioxidant capacity and selenium serum concentrations in 14 patients with chronic hepatitis C and in 9 healthy subjects. Before therapy, mean urinary nitrite/nitrate levels of patients were not different from those of healthy subjects, but after a 6-month treatment with alpha-interferon and ribavirin, these NO metabolites were higher in virologically negative patients (responders). Moreover, while no changes in selenium were observed in all patients, total antioxidant capacity was significantly higher in non-responders and well correlated with hyperuricemia (due to cell damage) observed in these subjects. Instead, uric acid decreased as free molecule in serum in responders, while we found the excretion of high NO levels as nitrite/nitrate. Our data allow us to hypothesize a role for NO as predictive of the success of therapy, since nitrite/nitrate increase in the urine of some patients precedes disappearance of the virus observed at the end of therapy. 相似文献
23.
C J Smith T A Perfetti M A Rumple A Rodgman D J Doolittle 《Food and chemical toxicology》2001,39(2):183-205
In the third and final part of a series surveying the international literature on the "IARC carcinogens" in cigarette mainstream smoke, the "IARC Group 2B carcinogens" are reviewed. A search of the published literature shows that of 227 chemical components classified as Group 2B, that is, "possible carcinogens," by the International Agency for Research on Cancer (IARC), 48 have previously been reported in cigarette mainstream smoke. Owing to its highly interactive molecular nature, removal from or inhibition of a given mutagenic or carcinogenic chemical within the complex aerosol mixture cannot reliably be predicted to reduce either the overall mutagenicity or carcinogenicity. However, in the absence of experimental data demonstrating an increase in adverse biological activity resulting from removal or inhibition of a potentially carcinogenic constituent, negation of the activity of the potential carcinogen may be considered as a desirable circumstance. 相似文献
24.
De Stasio G Casalbore P Pallini R Gilbert B Sanità F Ciotti MT Rosi G Festinesi A Larocca LM Rinelli A Perret D Mogk DW Perfetti P Mehta MP Mercanti D 《Cancer research》2001,61(10):4272-4277
157Gd is a potential agent for neutron capture cancer therapy (GdNCT). We directly observed the microdistribution of Gd in cultured human glioblastoma cells exposed to Gd-diethylenetriaminepentaacetic acid (Gd-DTPA). We demonstrated, with three independent techniques, that Gd-DTPA penetrates the plasma membrane, and we observed no deleterious effect on cell survival. A systematic microchemical analysis revealed a higher Gd accumulation in cell nuclei compared with cytoplasm. This is significant for prospective GdNCT because the proximity of Gd to DNA increases the cell-killing potential of the short-range, high-energy electrons emitted during the neutron capture reaction. We also exposed Gd-containing cells to thermal neutrons and demonstrated the GdNC reaction effectiveness in inducing cell death. These results in vitro stimulated in vivo Gd-DTPA uptake studies, currently underway, in human glioblastoma patients. 相似文献
25.
Type 2 diabetes is characterized by two fundamental biological defects: a reduced glucose-dependent insulin secretion and an increased resistance to the action of insulin at the level of various target tissues. While the use of agents to improve the insulin secretory activity of the islets of Langerhans has witnessed the flourishing of several new drugs over the years, a much greater difficulty has been experienced in the search for insulin-sensitizing drugs. The aim of this article is to critically review this topic, and to emphasize the importance of providing alternative strategies for the management of Type 2 diabetes. 相似文献
26.
27.
BACKGROUND: HDM distribution varies between geographic areas and may be affected by housing characteristics. We quantified Der p 1 and Der f 1 and assessed the relationships between their levels and housing characteristics in homes of nonallergic subjects. METHODS: Der f 1 and Der p 1 were measured by ELISA in dust samples from living-room floors and mattresses of 44 homes of nonallergic subjects in Pavia. Information about household characteristics was obtained by questionnaire. RESULTS: Der p 1 and Der f 1 concentrations (microg/g dust, median) were 0.34 and 7.8 on mattresses, and 0.15 and 0.83 on living-room floors. Higher Der f 1 levels on mattresses were associated with synthetic pillows (P<0.05), and (only when expressed as microg/m2) with bedding washing temperature of < or = 60 degrees C (P<0.05). Der f 1 levels were higher on the living-room floors of homes located on lower (< or =first) floors (P<0.05). Good correlations were found between Der p 1 and Der f 1 expressed as microg/g dust and microg/m2 on both mattresses and living-room floors. CONCLUSIONS: In homes of nonallergic subjects in northern Italy, Der f 1 exceeded the threshold for sensitization in a high proportion of mattress samples. 相似文献
28.
The degrees of plasma cell clonality and marrow infiltration adversely influence the prognosis of AL amyloidosis patients 总被引:4,自引:0,他引:4
Perfetti V Colli Vignarelli M Anesi E Garini P Quaglini S Ascari E Merlini G 《Haematologica》1999,84(3):218-221
BACKGROUND AND OBJECTIVE: Primary amyloidosis is a lethal form of plasma cell (PC) dyscrasia characterized by deposits of monoclonal immunoglobulin light chains that cause organ dysfunction. In contrast to multiple myeloma, the amyloid clone is typically indolent and of small size, and marrow PC clonality is not always apparent. This is generally investigated by analyzing the light chain isotype ratio in bone marrow PC. We investigated whether the degree of PC infiltration (PC%) and clonality (PC isotype ratio) affected survival in 56 consecutive patients with primary amyloidosis. DESIGN AND METHODS: PC% was determined by morphologic examination. Immunofluorescence microscopy was used to determine the PC light chain isotype ratio. Statistical analysis was carried out using Cox regression models. RESULTS: The degrees of PC clonality and infiltration were inversely correlated with survival (PC isotype ratio, p = 0.001; PC%, p = 0.008). The two variables were weakly correlated (p = 0.02; r = 0.3). Bone marrow PC isotype ratio demonstrated a powerful independent prognostic value at multivariate analysis when analyzed together with congestive heart failure (the major known negative prognostic factor) and PC%. k/l ratio cut-off values of 0.2 (l patients, p = 0.022) and 16 (k patients, p = 0.03) discriminated two groups with a similar number of patients and significantly different survivals. INTERPRETATION AND CONCLUSIONS: PC clonality and marrow infiltration are important parameters that influence prognosis, presumably because they reflect the amount of pathogenic light chain synthesis. 相似文献
29.
de Jager LS Perfetti GA Diachenko GW 《Journal of pharmaceutical and biomedical analysis》2006,41(5):1552-1559
A method was developed for the extraction and quantification of five marker compounds characteristic of Ginkgo biloba. Five ginkgo terpene trilactones: bilobalide and ginkgolides A, B, C, and J, were selected as marker compounds for this study. Initial studies produced a simple methanol extraction method for determination of gingko markers in solid dietary supplements. Five dietary supplements were analyzed and the results were later compared to the concentrations detected in the analysis of beverages. Beverage samples were prepared by extracting the ginkgo terpene trilactones using an optimized solid phase extraction (SPE) method. The extracts were analyzed using LC–atmospheric pressure chemical ionization (APCI)–MS in the negative ionization mode. The limits of detection of the extraction method ranged from 6.8 to 3.2 ng mL−1. Using the optimized method, 14 drinks and 3 tea products were analyzed. Concentrations of total marker compounds in drinks ranged between 1685 and 21.4 ng mL−1 with individual ginkgo terpene trilactones being detected at ppb concentrations. Analysis of brewed tea products presented much higher total marker compound concentrations ranging from 8.12 and 16.6 μg mL−1. Analytical results reproducibility data, and recovery of the SPE method are presented. 相似文献
30.