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71.
In this study, we investigated some bone parameters (bone mineral content, bone mineral density, skeleton area) in growing rats fed with a high fat diet. Correlations between bone and body composition parameters are reported. Two groups of Wistar male rats (35 days old, body mass 80 ± 6 g) were used. Water and food were given " ad libitum " during 10 weeks. Sixteen rats (L) were given a lipid enriched diet and were compared to 16 rats (S) fed with a standard diet. Body composition and bone parameters were assessed using DXA. Results indicated that L rats had lower body mass, lean body mass; fat mass was not different between the two groups. Bone mineral content, bone mineral density, skeleton area of L rats were lower compared with S rats. Significant correlations were noted between body composition, adiponectin and bone parameters. High fat diet intake during the growing period has deleterious effects on bone parameters in rats. This study confirms in growing rats that a high fat diet is pathogenic, including bone metabolism.  相似文献   
72.
J E Fletcher  K Michaux  M S Jiang 《Toxicon》1990,28(6):647-656
Melittin from bee venom has been suggested to activate tissue phospholipase A2 (PLA2) activity, and subsequently has been used as a specific PLA2 probe. The melittin in most cases was obtained commercially and used without further purification or treatment. To test the hypothesis that commercially obtained melittin specifically activates tissue PLA2, we radiolabeled the lipids of immortalized epithelial cells by incubating the cells for 22 hr with 14C-linoleic acid. The cells were then incubated with 2 microM melittin, 2nM bee venom PLA2, 2 microM melittin treated with p-bromophenacyl bromide (p-BPB) or PLA2 plus p-BPB-treated melittin. Lipids were extracted and separated by thin-layer chromatography. The radioactivity in each lipid fraction was then quantitated. The melittin-stimulated PLA2 activity observed in cells was primarily associated with phosphatidylcholine. Fatty acid release was decreased by 75% when the melittin fraction was pretreated with p-BPB to reduce contaminating venom PLA2 activity. Adding PLA2 to the p-BPB-treated melittin at an amount about equal to the original contamination (0.1%) resulted in the same PLA2 activity in cell as observed with the untreated melittin fraction. These findings suggest that bee venom PLA2 contamination, even at very low levels, can account for approximately 75% of the PLA2 activity in cells treated with commercial melittin fractions.  相似文献   
73.
Aberrations of TP53 (mutations and/or deletions) are associated with a dismal prognosis in chronic lymphocytic leukemia (CLL). Complete loss of ATM is another mechanism of failed DNA damage response and also associated with poorer prognosis in CLL. However, p53 dysfunction may arise through alternative mechanisms unrelated to structural aberrations (deletion and/or mutation) of TP53 or ATM, and thus be undetectable by traditional DNA-directed approaches (fluorescence in situ hybridization [FISH], sequencing, karyotyping). In order to address the latter changes, and also to better understand the consequences of TP53/ATM aberrations, p53 functional assays have recently been developed. The purpose of dynamic assessment of p53 response in CLL is to carry out a comprehensive analysis of all mechanisms causing p53-deficient phenotype, including those unrelated to genomic aberrations of TP53 and ATM. The present review focuses on the current knowledge of p53 function assays in CLL, including important features such as technical issues, correlation with structural aberrations and clinical value.  相似文献   
74.
The cold pressor test (CPT) is an empirically validated test commonly used in research on stress, pain and cardiovascular reactivity. Surprisingly, the equivalent test with water heated to noxious temperatures (hot water immersion test, HIT) has not been thoroughly investigated. The aim of the present study was to characterize the physiological effects and psychophysics of both tests and to analyze whether the autonomic responses are mainly induced by baroreflexes or a consequence of the pain experience itself. The study consisted of a single session including one CPT (4 ± 0.2 °C) and one HIT (47 ± 0.5 °C; cut‐off point 5 min) trial performed on 30 healthy drug free volunteers aged 19–57 (median 24) yrs. The sequence of both trials was alternated and participants were randomly assigned to sequence order and parallelized with respect to gender. Physiological parameters (cardiovascular, respiratory and electrodermal activity) and subjective pain intensity were continuously monitored. In addition, pain detection and tolerance thresholds as well as pain unpleasantness were assessed. Both tests were comparable with regard to the time course and intensity of subjective pain. However, a significantly higher increase of blood pressure could be observed during the CPT when compared to the HIT. The HIT appears less confounded with thermoregulatory baroreflex activity and therefore seems to be a more appropriate model for tonic pain.  相似文献   
75.
76.
This study describes the diagnosis and treatment of a spontaneous intramyometrial pregnancy by a case report and review of the literature at a university hospital center. A 24-year-old woman presented with a spontaneous intramyometrial pregnancy without any previous uterine surgery. Successful laparoscopic resection and myometrial correction were performed. The presence of trophoblastic tissue was confirmed and the myometrium revealed complete healing at postoperative MRI. Intramyometrial pregnancy can occur without previous uterine surgery or uterine manipulation and may be difficult to diagnose. Conservative laparoscopic excision is possible without damage to myometrial integrity.  相似文献   
77.
BACKGROUND AND OBJECTIVES: It may be useful to reduce the exposure of transplant recipients to homologous blood. This may be achieved by procuring donor-derived red blood cell (RBC) units, collecting more peripheral blood progenitor cells (PBPC) with a combination of granulocyte colony-stimulating factor (G-CSF) + recombinant human erythropoietin (rHuEpo) and by administering rHuEpo post-transplantation. DESIGN AND METHODS: Eight ABO-compatible donors were treated with rHuEpo and intravenous iron to collect 12 RBC units for use in their recipients. PBPC were collected after mobilization with rHuEpo and G-CSF in the same donors. The recipients received G-CSF and rHuEpo post-transplantation. A control group of 10 donor/recipient pairs received G-CSF alone for PBPC mobilization and after the transplantation. RESULTS: Eighty-six out of 91 planned RBC units were collected in the donors without significant decrease in hematocrit because of a 4-fold increase in RBC production despite functional iron deficiency. After 2 leukaphereses, the cumulative yields of NC and CFU-GM were lower in the study group while those of BFU-E, CFU-Mix and CD34+ cells were similar. However, erythroid recovery was significantly accelerated in the study group. INTERPRETATION AND CONCLUSIONS: Collection of 12 RBC units within 6 weeks is feasible with rHuEpo and intravenous iron; this strategy allows a dramatic reduction in recipient exposure to homologous blood; rHuEpo has no synergistic effect with G-CSF for mobilization of PBPC in normal donors and may even be deleterious; and rHuEpo in the recipient may enhance erythroid engraftment.  相似文献   
78.
Cytogenetic studies were performed on 25 chronic myelogenous leukemia patients aged between 6 mo and 19 yr. Of these, 14 presented with the adult form and 11 with the juvenile form of the disease. In patients with the adult type, 12 of 14 had a Ph chromosome and additional anomalies appearing during blastic transformation. In the patients with the juvenile form, 6 of 11 had a monosomy 7 and a short survival time (median 10 mo). Salient features of these patients, as well as a survey of the pertinent literature on the subject, are presented in this paper.  相似文献   
79.
Sickle cell anaemia is still responsible for severe crippling and death in young patients living in developing countries. Apart from prophylaxis and treatment of infections, no active treatment can be safely proposed in such areas of the world. Therefore a bone marrow transplantation was performed in 12 patients staying in Belgium and planning to return to Africa. Twelve patients, aged between 11 months and 23 years (median 4 years), underwent a HLA identical bone marrow transplantation. The conditioning regimen included oral busulphan for four consecutive days (4 mg/kg) followed by four days of intravenous cyclophosphamide (50 mg/kg). In 10 patients the engraftment was rapid and sustained. A further patient suffered transient red cell hypoplasia and another underwent a second bone marrow transplantation from the same donor at day 62 because of graft rejection. All patients are alive and well with a follow up ranging from 9-51 months (median 27 months). In all cases a complete cessation of vaso-occlusive episodes and haemolysis was observed as was a change in the haemoglobin pattern in accordance with the donor''s electrophoretic pattern.  相似文献   
80.
Observations made in two patients and a review of the literature confirm the occurrence of a 5q- chromosome anomaly in lymphoproliferative disorders of both T and B cell type. Additional chromosome changes were invariably present and are of the "lymphoid" type. The chromosome morphology of the 5q- is indistinguishable from that found in myeloid disorders.  相似文献   
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