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51.
Results of second-line chemotherapy regimens against lymphoma have usually been poor. In this study, we used a combination of ifosfamide, methotrexate, and VP-16 to treat 52 patients with lymphoma who had either relapsed or who had failed to attain a complete remission on front-line treatment. Thirty-two patients (62%) responded (CR 37%, PR 25%) and 10 (19%) had a minor response. The median relapse-free interval of the responding patients was 12 mo, and the median survival of the whole group was 15 mo. Of the 18 patients who achieved complete remission, 10 still remain free of any evidence of disease. The factor that best predicted for response to IMVP-16 was the quality of the remission achieved on front-line therapy. In view of the poor prognosis associated with recurrent lymphoma, the results obtained with this study are considered most encouraging. Patients with recurrent lymphoma can be successfully salvaged by the use of this combination regimen, especially if introduced early after relapse or preferably before progressive disease develops.  相似文献   
52.
Interleukin (IL)-12 is thought to be a key factor for the induction of interferon gamma (IFN-gamma), a cytokine essential for the lethal effects of endotoxin. We report here on the release of the nonfunctional subunit of IL-12, p40, as well as biologically active heterodimeric IL-12, p70, after administration of a lethal (n = 5) or sublethal (n = 8) dose of live Escherichia coli to baboons. Remarkably, on lethal challenge, peak levels of p40 were observed at 3 hours that were about twofold lower than those elicited after sublethal challenge (2,813 +/- 515 pg/mL v 4,972 +/- 732 pg/mL, P < .05). This disparity was also observed, although to a lesser extent, for IL-12 p70 antigen, of which maximum levels of 91 +/- 47 pg/mL and 151 +/- 41 pg/mL were measured 6 hours after a lethal or sublethal dose of E coli, respectively. Circulating p70 antigen correlated with IL-12 biologic activity (r = 0.869; P < .001). When comparing lethal to sublethal conditions, lower peak levels of IL-12 on lethal E coli sharply contrasted with higher levels of other proinflammatory cytokines, such as tumor necrosis factor (TNF)-alpha, IL-1beta, IL-6, and IL-8 observed in these animals. Lower IL-12 concentrations in the lethal group may have resulted in part from the enhanced production of IL-10, a known inhibitor of IL-12 synthesis in vitro, as peak levels of this cytokine 3 hours postchallenge inversely correlated with peak levels of IL-12, in particular p40 (r = -0.802; P < .01). Contrary to what might be expected if IFN-gamma were solely induced by IL-12, lethally challenged baboons generated threefold more IFN-gamma at 6 hours than those receiving a sublethal dose (P < .05). Moreover, higher levels of IFN- gamma were associated with lower p40/p70 ratios, suggesting that, in agreement with observations in vitro, IFN-gamma may have preferentially upregulated the release of p70 over p40. These data show that IL-12 is released in experimental septic shock in nonhuman primates and suggest that IL-10 and IFN-gamma are involved in the regulation of this release. Furthermore, this study indicates that the systemic release of IL-12 might be essential, but is not likely sufficient, to promote lethal production of IFN-gamma in sepsis.  相似文献   
53.
Homocysteine is a risk factor for cardiovascular disease and venous thrombosis. Clinical guidelines differ in their recommendation whether or not to measure homocysteine after methionine loading. In this study, we investigated the added value of the methionine loading test next to fasting homocysteine levels for identifying subjects at risk for venous thrombosis or cardiovascular disease, using Receiver Operating Characteristic (ROC) curves.The analysis was performed in 185 patients with recurrent venous thrombosis, 130 patients with cardiovascular disease and 601 controls.The discriminatory power of the fasting homocysteine measurement alone for identifying subjects at risk of venous thrombosis expressed as the area under the ROC curve (AUC) was 0.61 (95%CI 0.56-0.66). Using both a fasting homocysteine measurement and a methionine loading test together yielded a similar AUC of 0.65 (95%CI 0.60-0.69), indicating no added value of methionine loading next to fasting homocysteine measurement in identifying subjects at risk for thrombosis. Similar results where found for cardiovascular disease,with an AUC of 0.62 (95%CI 0.57-0.67) for the fasting homocysteine measurement alone and an AUC of 0.62 (95% CI0.57-0.67) for the combination of both the fasting and the post-load homocysteine measurement. The methionine loading test has no added value next to measuring fasting homocysteine levels for identifying subjects at risk for venous thrombosis or cardiovascular disease and for that reason should not be used in clinical practice.  相似文献   
54.
Background: The degradation of sevoflurane can lead to the production of compound A (CA) and carbon monoxide (CO) and an increase in temperature of the absorbent. CA is known to be nephrotoxic in rats. These reactions depend on the strong base and water contents of the carbon dioxide absorbent used. The purpose of this study was to measure the maximum amounts of CA and CO produced, and the temperature increase, for seven different carbon dioxide absorbents for sevoflurane containing different contents of strong bases. Methods: Seven absorbents [some free of strong bases (f)] were employed in hydrated (h) and completely desiccated (d) conditions in a patient model, using a circle anesthesia system connected to an artificial lung. Low‐flow anesthesia with an oxygen–nitrous oxide mixture was maintained using 0.8% sevoflurane. For the quantification of CA and CO, a portable gas chromatograph was used. The temperature was measured inside the absorbent. Results: In consecutive order of CA‐producing potency, Amsorb®(f)(d), Drägersorb(h), Medisorb®(h), lithium hydroxide(f)(d), Drägersorb(d), Medisorb®(d), Spherasorb®(h) and Spherasorb®(d) produced small amounts of CA. Loflosorb® and Superia®, which are free of strong bases, did not produce any CA or CO in hydrated or desiccated conditions. Only desiccated Drägersorb®, Medisorb® and Spherasorb® demonstrated small amounts of CO accompanied by a significant temperature increase. Conclusion: In this patient model, we demonstrated that different types of absorbent produced small amounts of CA and CO or none at all. No relationship could be established between temperature and CA concentration.  相似文献   
55.
Background In some of our patients with intellectual disabilities (ID) and sleep problems, the initial good response to melatonin disappeared within a few weeks after starting treatment. In these patients melatonin levels at noon were extremely high (>50 pg/ml). We hypothesise that the disappearing effectiveness is associated with slow metabolisation of melatonin because of a single nucleotide polymorphism (SNP) of CYP1A2. Method In this pilot study we analysed DNA extracted from saliva samples of 15 consecutive patients with disappearing effectiveness of melatonin. Saliva was collected at noon and 4 pm for measuring melatonin levels. Results In all patients' salivary melatonin levels at noon were >50 or melatonin half time was >5 h. A SNP was found in eight of 15 patients. The allele *1C was found in two patients and in six patients the *1F allele was found. Conclusions Of 15 patients with disappearing effectiveness of melatonin, seven were diagnosed with autism spectrum disorder, and in four of them a SNP was found. The other eight patients were known with a genetic syndrome. In six of them behaviour was considered to be autistic‐type and in three of them a SNP was found. This finding may give a new direction for research into the genetic background of autism.  相似文献   
56.
ObjectivesInvestigation of falsely elevated HbA1c measurements on the HLC-723 G7 analyser.Design and methodsComparison of HbA1c in blood samples that were diluted either in hemolysis reagent or water.ResultsHbA1c results became falsely elevated when samples were diluted in hemolysis reagent, but not in water. QC-procedures failed to detect this error as calibrator and QC samples were manually diluted in water, according to manufacturer's instructions, whereas patient samples were automatically diluted using hemolysing reagent. After replacement of the instruments' sample-loop and rotor seal comparable HbA1c results were obtained, irrespective of dilution with hemolysing reagent or water.ConclusionThis case illustrates the importance of treating calibrator and QC materials similar to routine patient samples in order to prevent unnoticed drift in patient HbA1c results.  相似文献   
57.
Neonates with congenital diaphragmatic hernia (CDH) suffer from a diaphragmatic defect, lung hypoplasia, and pulmonary hypertension, with poor lung function forming the major clinical challenge. Despite prenatal diagnosis and advanced postnatal treatment strategies, the mortality rate of CDH is still high. CDH has been subject of extensive research over the past decades, but its etiology remains unknown. A major problem with CDH is the failure to predict the individual response to treatment modalities like high-frequency ventilation, inhaled nitric oxide, and extracorporeal membrane oxygenation. In this study, we tested the possibility that CDH lungs are surfactant protein deficient, which could explain the respiratory failure and difficulties in treating CDH infants. We investigated this hypothesis in the nitrofen-induced CDH rat model and assessed the cellular concentrations of surfactant protein (SP)-A, -B, and -C mRNA with a quantitative radioactive in situ hybridization technique. No differences were observed between control and CDH lungs for SP mRNA expression patterns. The cellular concentration (mean OD) of SP-A and SP-B mRNA was similar at all stages whereas the mean OD of SP-C mRNA and the volume fraction of cells (% Area) expressing SP mRNA was higher in CDH lungs at term. Immunohistochemical analysis revealed no differences between control and CDH lungs for SP protein expression. No differences in the mean OD or % Area for the SP mRNAs were found between the ipsi- and contralateral side of CDH lungs. We conclude that there is no primary deficiency of surfactant proteins in the nitrofen-induced CDH rat model.  相似文献   
58.
Cardiac function was measured in 16 prepubertal Ecuadorean patients with growth hormone receptor deficiency given insulin-like growth factor I (IGF-I) during part of a clinical trial. The IGF-I was given subcutaneously twice daily at a dose of 40 μg/kg on days 1 and 2, 80 μg/kg on days 3 and 4, and 120 μg/kg thereafter. Heart rate was determined at baseline (pretreatment) and on days 1–7 by repeated palpation of the radial artery and at baseline and on days 2, 4 and 7 by continuous portable Holter monitoring. Heart rate measured by both methods rose progressively with increasing doses of IGF-I. The mean palpated pulse exceeded baseline on each treatment day and was significantly higher on day 5 than day 4 and significantly higher on day 3 than day 2. The mean Holter heart rate was significantly higher on day 4 than on day 2 and significantly higher on day 2 than at baseline. Non-significant glucose and electrolyte changes did not appear to be associated with the cardiac events.  相似文献   
59.
The molecular distribution of insulin-like growth factor I (IGF-I) and IGF-II among the IGF binding proteins (IGFBPs) was studied before and during IGF-I therapy in Ecuadorean adults with growth hormone receptor deficiency (GHRD). Of the total circulating IGF-I and IGF-II, 70% was carried by the 150 kDa complex in normal subjects, while in patients with GHRD, 50% of serum IGF-I, but only 30–35% of serum IGF-II, was measured within the 150 kDa IGFBP-3 region. Administration of IGF-I altered the concentration of IGF-I and IGF-II, although the percentage of total IGF measured within each IGFBP region was not affected, as the increase in IGF-I and the decrease in IGF-II were proportional. Similarly, serum concentrations of IGFBP-3 and the acid-labile subunit, measured by radioimmunoassay, were unaltered. Thus, administration of IGF-I to patients with GHRD was unable to correct the aberrant distribution of IGFs among the IGFBPs.  相似文献   
60.
We report a case of a 45-year-old woman who exhibited a primitive eccrine sweat gland carcinoma of the eyelid. Histological study showed cellular proliferation with an Indian file pattern and some signet ring cells with sialomucin secretion. Immunohistochemical study demonstrated these cells to be positive with the anticytokeratin, anti-EMA, anti-HMFG, antiestrogen receptor and antiprogesterone receptor antibodies. Ultrastructural study showed intracytoplasmic vacuoles with numerous microvilli at the apical side. Differential diagnosis with a metastasis from a mammary adenocarcinoma is difficult and a complete staging is necessary to confirm the primitive origin of the tumor. The behavior of this tumor is marked by locoregional recurrence.  相似文献   
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