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1.
BACKGROUND: Abnormalities in calcium and vitamin D metabolism have been reported after bariatric surgery. The purpose of this study was to evaluate vitamin D nutritional status among morbidly obese patients before gastric bypass surgery. METHODS: We prospectively studied 279 morbidly obese patients seeking gastric bypass surgery for vitamin D nutritional status as assessed by serum 25-hydroxyvitamin D level. In addition, serum samples were analyzed for calcium, alkaline phosphatase (AP), intact parathyroid hormone (PTH), and 1,25-dihydroxyvitamin D. RESULTS: Mean patient age was 43 +/- 9 years; 87% of the study patients were women, and 72% were white. Serum calcium and AP levels were normal in 88% and 89% of the patients, respectively. Vitamin D depletion, defined as serum 25-hydroxyvitamin D level 相似文献   
2.
Small bowel transplantation (SBT) is associated with a high incidence of infectious complications because of ischemia/reperfusion (I/R) mucosal injury concomitant with potent immunosuppression. In this study, we evaluated whether the cavitary two-layer method (cTLM) could reduce I/R injury and allow early mucosal restoration, particularly after prolonged preservation and transplantation. Canine heterotopic segmental SBT was performed immediately without preservation (group 1), after 24-h preservation in UW solution (group 2) or by the cTLM (group 3). The graft samples were taken 1 h after reperfusion and on days 1, 4 and 7. We assessed graft mucosa with detailed microscopic and electromicroscopic analyses. In Group 3, histological injury and cell apoptosis after transplantation were significantly alleviated and rapidly recovered to a similar level of group 1. The mucosal restoration was morphologically completed within 4 days. In contrast, in group 2, more pronounced mucosal injury and delayed recovery were noted. Crypt cell proliferation activity was well maintained in groups 1 and 3 throughout the experimental period. Our ultrastructural analysis suggested that mitochondrial integrity achieved by the cTLM was a basal mechanism under the prompt mucosal restoration. The cTLM could reduce I/R injury, facilitate mucosal regeneration and restore the nearly normal structure early after SBT.  相似文献   
3.
We evaluated a protocol for the accelerated detection of extended-spectrum beta-lactamases (ESBLs) in gram-negative bloodstream pathogens. Two hundred eighty-three blood culture bottles were subjected to direct ESBL testing by inoculating samples directly from blood culture bottles onto agar plates containing cefotaxime and ceftazidime disks, with and without clavulanate. Standard ESBL testing in accordance with the NCCLS guidelines after subculturing on agar plates was performed in parallel. Results of the direct ESBL testing were reported 2.3 days sooner and were comparable to those of the standard NCCLS method with sensitivity, specificity, and positive and negative predictive values of 100, 98, 94, and 100%, respectively.  相似文献   
4.
The diagnosis of bloodstream infection with coagulase-negative staphylococci is frequently based on the isolation of the same organism from more than one blood culture. Phenotypic variation is a common characteristic of pathogenic strains of Staphylococcus epidermidis which may affect species identification by the microbiology laboratory. We describe a patient with a new onset of nephritis and gram-positive bacteremia. Gram-positive cocci grew in multiple blood cultures and were identified by the Vitek 2 system as Kocuria varians, Staphylococcus hyicus, and S. epidermidis. Bacterial isolates grew on blood agar and Congo red agar plates as two distinct morphotypes and exhibited phenotypic variation. Neither morphotype could be identified by the API-Staph assay. Cellular fatty acid analysis identified one of the morphotypes as S. epidermidis but could not identify the other morphotype. All isolates were found to be identical by pulsed-field gel electrophoresis, and both colonial morphotypes were identified as S. epidermidis by 16S ribosomal gene sequencing. Phenotypic variation of S. epidermidis may affect identification to the species level by phenotype-based identification systems. Caution should be exercised when differentiating between true infection and contamination based on strain identification.  相似文献   
5.
A series of binary vehicles was used to deliver physostigmine across dermatomed human skin. The vehicles consisted of isopropyl myristate (IPM) and isopropyl alcohol (IPA) mixed in various volume fractions. The kinetics of penetration is conveniently considered as the sum total of two contributing effects: a "push" process resulting from the excess free energy (delta EG) of the penetrant in the donor vehicle, and a "pull" process resulting from the effect of IPA and IPM on the skin barrier. The inverse ratio of the solubility of the drug in a given vehicle to that in pure IPA was used to estimate the relative delta EG, hence the relative "push" effect. The solubility of physostigmine was highest in pure IPA (delta = 11.5), lowest in pure IPM (delta = 8.5), and intermediate in their various mixtures. But the permeability coefficient (Kp) of physostigmine was highest when delivered from a 1:9 (v/v) solution of IPA:IPM and a calculated delta y = 8.8. A further increase in the volume fraction of IPA caused an opposite decrease in the Kp values of physostigmine. The "steady-state" flux (Jss) of IPA from the same vehicle was lowest at a volume fraction of 1:9 and highest at one of 1:1 IPA:IPM. Thus, the maximal physostigmine penetration enhancing effect of IPA occurs at the lowest flux of IPA found in the present series. This indicates that the "pull" process ascribed to the presence of IPA in the barrier membrane is not important enough to outweigh the decrease in delta EG of physostigmine following an increase in the volume fraction of IPA in the donor vehicle, or that an excess of IPA in the barrier is not conducive to further enhancement of physostigmine diffusivity across the barrier. Optimized percutaneous delivery of physostigmine is possible by thermodynamic control of the penetration process.  相似文献   
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Introduction Neonatal hyperthyrotropinaemia (HT), defined by elevated TSH and normal T4, is either transient or persistent. The eventual outcome of neonatal HT is unpredictable and the management of HT patients is controversial. We assessed perinatal parameters and diagnostic measures that may distinguish between transient and persistent HT, compared with congenital hypothyroidism (CH). We also aimed to recommend optimal treatment in these forms of thyroid impairment. Design and patients A multi‐centre, retrospective study was conducted in six paediatric endocrinology units. Forty‐three HT patients and 83 CH patients were included in the study. Measurements We evaluated differences in birth weight (BW), gestational age (GA), modes of diagnosis, screening and confirmatory T4 and TSH levels, thyroid imaging results and optimal thyroxine doses between HT and CH and between the two forms of HT. Results Newborns with HT had lower BW and GA than those with CH. Transient (n = 18) and persistent HT (n = 25) patients were indistinguishable by most parameters, but those with persistent HT had a higher prevalence of abnormal thyroid imaging (69%vs 8%; P = 0·005). During treatment, 79% and 55% of transient and persistent HT patients respectively experienced elevated levels of free T4. Although most HT patients were reevaluated after 2·5 years, six transient HT patients stopped therapy and showed full recovery within the first year of life. Conclusions We recommend obtaining thyroid imaging to distinguish between the two forms of HT. Adherence to recommended doses of thyroxine and probably early cessation of therapy in transient HT can prevent iatrogenic hyperthyroidism in these patients.  相似文献   
9.
Increase of distribution of environmental contaminants such as heavy metals have been caused the knowledge of the safety and hygiene of food is very important, especially eggs, because of its role in the daily diet. There are very few studies about the investigation of the heavy metal contents in egg-white. In this study, six heavy metals include Aluminium (Al), Arsenic (As), Lead (Pb), Cadmium (Cd), Mercury (Hg), Antimony (Sb) in egg-white from 32 industrial poultry farms were investigated, by ICP-OES. All the samples were collected in all area of Markazi Province, Iran in autumn 2013. The mean concentrations of heavy metals in egg-white as follows: 0.119 for Al, 0.785 for As, 0.750 for Pb, 0.249 for Cd, 0.270 for Hg and 0.186?mg/kg for Sb. Also, the concentration of the some heavy metals were higher than maximum allowable concentration that probably it is associated to use pesticides and activities of industrial factories around the poultry farms.  相似文献   
10.
The natural history of KPC-producing Klebsiella pneumoniae (KPC KP) carriage is unknown. We aimed to examine the duration of KPC KP carriage following hospital discharge and to study the risk factors for persistent carriage. A cohort of 125 KPC KP carriers was followed monthly for between 3 and 6 months after discharge from an acute-care hospital. Rectal swabs and data were collected at baseline and at each visit. KPC KP was detected by culture and direct blaKPC PCR. Acquisition time was regarded as the earliest date of KPC KP isolation. Resolution of carriage was defined as a negative KPC KP test in at least two consecutive samples. Analyses were separated for recent (<4 months) (REC, 75 patients) and remote (≥4 months) (REM, 50 patients) acquisition groups. Risk factors for persistent carriage were examined by survival analyses for the REC group and by prevalence methods for the REM group. The mean age of patients was 67.5 years and 49.6% were male. Forty-six (61%) patients in the REC group and 14 (28%) in the REM group were persistent carriers (p < 0.001). A significant risk factor for persistent carriage identified in both the REC and REM groups was the presence of any catheter (p < 0.05). Unique risk factor groups included long-term care facility (LTCF) residence (p < 0.01) and a low functional status as measured by the Barthel’s index (p < 0.05) in the REC group and high Charlson’s score in the REM group (p < 0.05). Out of the entire 100 patients who had at least one negative sample, only 65 remained negative on subsequent cultures. In conclusion, persistent carriage of KPC KP is associated with catheter use and a low functional status; it is more common in patients with recent acquisition and is related to LTCF stay. A single negative KPC KP test is insufficient to exclude persistent carriage.  相似文献   
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