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A rare case of primary thyroid papillary carcinoma arising in a thyroglossal duct cyst occuring in a 46 year old man is reported. The diagnosis was not suspected preoperatively. On gross examination of the excised specimen the presence of a papillary tumour in the cystic mass suggested the diagnosis which was proved histopathologically. The thyroid gland was normal on physical examination and scintigram thus ruling out the possibility of metastasis from a primary tumour in the thyroid gland. 相似文献
13.
We performed a dual isotope, gated adenosine stress myocardial perfusion study on a 44-year-old man. Using filtered-back projection, images showed an inferior wall defect. However, intense liver uptake during adenosine stress was suspected to inaccurately cause diminished inferior wall counts. The patient has end-stage renal disease, diabetes mellitus, and hypertension. The excessive hepatic uptake was noted on planar rotating images and is likely related (at least in part) to reduced renal uptake (not shown subsequently). Using iterative reconstruction, the inferior cardiac defect was markedly reduced. The patient subsequently underwent surgery without complication. 相似文献
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BACKGROUND: Isoflurane increases extracellular dopamine concentration and causes trafficking of the dopamine transporter (DAT) in transfected cells. Also, the binding potentials of highly specific positron-emitting DAT ligands are altered by isoflurane in rhesus monkeys. The purpose of this study was to determine the dose-response curve for isoflurane altering the binding potential of one of these ligands ([F-18]FECNT) in humans. METHODS: Twenty human volunteers underwent positron emission tomography using [F-18]FECNT. All subjects were scanned while awake and then again after assignment to one of four groups (n = 5 each): awake-control, propofol-control, or light or deep isoflurane anesthesia as defined by Bispectral Index monitoring. Bispectral Index values in the light anesthesia group were 40 +/- 7 (end-tidal isoflurane, 1.02 +/- 0.08) versus 27 +/- 10 (end-tidal isoflurane, 1.6 +/- 0.3) in the deep anesthesia group. The within-subject percent change in putamen binding potential between the awake and second scans was determined for each subject, averaged within groups, and compared across groups. RESULTS: The [F-18]FECNT binding potential exhibited a biphasic shape as a function of anesthetic dose. The binding potential for the second scan in the awake-control and propofol-control groups was significantly less than the initial scan; for the light anesthesia group, the binding potential was significantly increased during anesthesia, and no change was detected between the two scans in the deeper anesthesia group. CONCLUSION: Isoflurane causes a dose-dependent change in the [F-18]FECNT binding potential for DAT consistent with isoflurane causing trafficking of the DAT between the plasma membrane and the cell interior. Concentrations of isoflurane below minimum alveolar concentration causes DAT to be trafficked to the plasma membrane from the cell interior, but no net trafficking occurs at higher concentrations. The data are most easily explained if isoflurane alters the amount of functionally expressed DAT through an indirect pathway. This phenomena should be more fully explored to help make the next generation of anesthetics more mechanistically specific and to reduce undesired side effects. 相似文献
15.
OBJECTIVES: The reasons for the very low incidence of the disease neurolathyrism in humans even after excessive consumption of the pulse, Lathyrus sativus, under severe drought and famine conditions, and its continued consumption by large populations during normal periods without any deleterious effects have been examined in the context of a possible metabolism or detoxification of beta-N-oxalyl-L-alpha, beta-diaminopropionic acid (ODAP), the major neurotoxic amino acid of L. sativus. DESIGN AND METHODS: ODAP in urine samples from 54 subjects habitually consuming the pulse and in three volunteers on an L. sativus diet was determined by the OPT method following clean up of the samples on an alumina column. Urinary oxalate was also determined in these individuals. RESULTS: Twenty-five subjects showed no excretion of ODAP and it was only less than 0.7% of the dietary intake in the remaining 29 subjects. Urinary excretion of ODAP in three volunteers was also less than 1% with a peak excretion in the 4-h sample. The 4-h blood sample from one volunteer had a maximum ODAP concentration of 177 microM. The urinary oxalate content in the volunteers was nearly 3-fold higher compared to controls. CONCLUSIONS: The low excretion of dietary ingested ODAP in humans is in sharp contrast to that seen in animals and indicates a metabolism or detoxification of ODAP which may be unique to humans and may explain the low incidence of neurolathyrism. 相似文献
16.
Nayak SK Naik R Upadhyaya K Raghuveer CV Pai MR 《Indian journal of pathology & microbiology》2001,44(3):355-357
Mucinous carcinoma of the male breast is a very rare tumour. So far only about 8 cases have been reported in the literature most of which were diagnosed after surgical resection. Fine-needles aspiration biopsy even though a well established procedure for the evaluation of breast masses in female there are only occasional reports of aspirates form male breast masses. We herein-present one case of mucinous carcinoma of breast in a 65 year old male diagnosed by fine needle and confirmed by histopathology. 相似文献
17.
OBJECTIVE: Vitamin E is required by very low birth weight (VLBW) infants to prevent vitamin E deficiency. However, prolonged intravenous intakes of vitamin E >4 international units (IU)/kg/day often yield potentially toxic serum tocopherol levels. This study was designed to assess the frequency of potentially inadequate or excessive doses of intravenous vitamin E in parenteral nutrition for VLBW infants in the US. STUDY DESIGN: A questionnaire was sent to the 100 neonatal-perinatal training program centers listed in the 2003 directory (American Academy of Pediatrics (AAP)). Using the information provided for each neonatal unit, we calculated the doses of vitamin E (IU/kg/day) that would have been given to infants with body weights of 0.5, 1.0 and 1.5 kg in that unit. The doses were then recoded as inadequate if less than recommended (2.8 IU/kg/day, maximum 7 IU/day) by the American Society for Clinical Nutrition and the AAP, and excessive if >4 IU/kg/day, and frequencies were compared using chi2 analysis. RESULTS: The 65 centers that responded were predominantly among those that offered the highest level of subspecialty neonatal intensive care (level IIID). The predicted dose of vitamin E had a median value of 2.8 IU/kg/day for all three weights, and was no significantly different among the three weights. VLBW infants with weights of 0.5, 1.0 and 1.5 kg were predicted to receive doses <2.8 IU/kg/day in 12, 12 and 19% of the neonatal intensive care units (NICUs), respectively, and doses >4 IU/kg/day in 40, 31 and 10% of the NICUs, respectively. Excessive doses were significantly associated with body weight, with more frequent excessive doses at lower weight (p=0.0008). CONCLUSION: This survey showed a lack of uniformity of dosing of intravenous vitamin E in VLBW infants. The smallest infants (<1.0 kg) were receiving excessive, potentially toxic doses of vitamin E in a significant number of NICUs in the US in 2003. 相似文献
18.
Respiratory distress syndrome (RDS) causes significant hypoxia in extremely low birth weight (ELBW) infants. We report an ELBW infant with RDS and pulmonary hypertension whose hypoxia did not respond to inhaled nitric oxide but improved with inhaled prostacyclin. We propose that inhaled prostacyclin alleviated the hypoxia by stimulating surfactant secretion. 相似文献
19.
Joydeep Ghosh Michihiro Kobayashi Baskar Ramdas Anindya Chatterjee Peilin Ma Raghuveer Singh Mali Nadia Carlesso Yan Liu David R. Plas Rebecca J. Chan Reuben Kapur 《The Journal of clinical investigation》2016,126(7):2621-2625
Hyperactivation of the mTOR pathway impairs hematopoietic stem cell (HSC) functions and promotes leukemogenesis. mTORC1 and mTORC2 differentially control normal and leukemic stem cell functions. mTORC1 regulates p70 ribosomal protein S6 kinase 1 (S6K1) and eukaryotic initiation factor 4E–binding (eIF4E-binding) protein 1 (4E-BP1), and mTORC2 modulates AKT activation. Given the extensive crosstalk that occurs between mTORC1 and mTORC2 signaling pathways, we assessed the role of the mTORC1 substrate S6K1 in the regulation of both normal HSC functions and in leukemogenesis driven by the mixed lineage leukemia (MLL) fusion oncogene MLL-AF9. We demonstrated that S6K1 deficiency impairs self-renewal of murine HSCs by reducing p21 expression. Loss of S6K1 also improved survival in mice transplanted with MLL-AF9–positive leukemic stem cells by modulating AKT and 4E-BP1 phosphorylation. Taken together, these results suggest that S6K1 acts through multiple targets of the mTOR pathway to promote self-renewal and leukemia progression. Given the recent interest in S6K1 as a potential therapeutic target in cancer, our results further support targeting this molecule as a potential strategy for treatment of myeloid malignancies. 相似文献
20.