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41.
A complete family history was obtained for 501 patients with Wilms' tumor, treated in departments of pediatric oncology in whole France. The information was collected by self-questionnaire and/or by interview of parents. The proportion of bilateral cases is 4.6% and there are 12 patients (2.4%) with a positive family history of Wilms' tumor. The affected relatives are most often distant and no first degree relative was affected. Apart from the well-known associations with aniridia, hemihypertrophy, genitourinary anomalies, Beckwith-Wiedeemann, and Drash syndromes, there is also a significant excess of congenital heart defects (P = .008) which remains to be explained. Several findings support the bimutational hypothesis such as earlier diagnosis and increased parental age in bilateral cases. No particular anomalies and no increased frequency of childhood cancer were found in patients' relatives. The frequency of Wilms' tumor in relatives was estimated to be less than 0.4% in sibs, 0.06% in unclesand aunts, and 0.04% in first cousins. These figures are very different from those found in retinoblastoma and suggest that the mechanism may be more complex in Wilms' tumor. This conclusion is in agreement with molecular biology studies in tumors and linkage analysis in multiple case families which suggest that more than one locus is involved. © 1992 Wiley-Liss, Inc.  相似文献   
42.
Bile acids are believed to play a role in the etiology of colorectal cancer, and high fecal excretion of secondary bile acids was correlated with increased incidence of colon cancer. Recently, it was also reported that there is an increase in plasma of the secondary bile acid, deoxycholic acid in men with colorectal adenomas. Since deoxycholic acid is formed in the colon and absorbed into the portal systemic circulation, it was suggested that the blood concentration of this bile acid reflects the level of exposure of colonic cells to deoxycholic acid. The objective of this study was to investigate whether plasma deoxycholic acid level represents the fecal content of this bile acid in several animal species with different bile acid composition and deoxycholic acid contribution to the bile acid pool. Eight rabbits, hamsters, guinea pigs, and rats were used in this study. Blood samples and feces were collected on days 1, 3, 5 and 7. Bile samples were obtained only on day 7. The plasma, fecal and biliary bile acids were analyzed by gas chromatography-mass spectrometry. Bile acid composition and deoxycholic acid content varied greatly between the animal species studied. There was a variation in the concentration of total bile acids in the plasma and feces obtained at different times during the experiments, however, the bile acids profile remained constant throughout the study. The data obtained shows that although plasma bile acid profile was not similar to fecal bile acids profile, however, there was a significant correlation between the level of plasma and fecal deoxycholic acid. Plasma deoxycholic acid concentration might be a reliable biomarker for the degree of exposure of colon cells to this bile acid, and may be useful in further studies on the role of secondary bile acids in colon carcinogenesis.  相似文献   
43.
Vascular thoracic outlet syndrome generally affects young, active, otherwise healthy patients. The diagnosis is suspected by clinical presentation, and can be confirmed with angiography or venography. Conservative management has been associated with significant morbidity and long-term residual disability. We have used a multimodal treatment protocol that includes thrombolysis, anticoagulation, surgical decompression, and interventional procedures. Catheter-directed recombinant tissue-type plasminogen activator and intravenous heparin infusion are instituted at the time of diagnosis to promote recanalization and prevent propagation of thrombus. Surgical decompression of the thoracic outlet can be readily achieved by first rib resection during the same hospitalization. Postoperative venograms are obtained in all patients. Residual stenoses can be managed with angioplasty alone in some patients but more commonly require stent placement. We believe thrombolysis, anticoagulation, surgical decompression, and percutaneous interventions act synergistically to improve results of therapy in patients with vascular thoracic outlet syndrome.  相似文献   
44.
Peracetic acid (PAA) permeation in flash sterilization was studied using three different plastic infusion bags made of polypropylene and polyethylene, filled with glucose 5% or NaCl 0.9%. The pH was measured and acetic acid (AA) and PAA concentrations were made by reverse phase high-performance liquid chromatography (RP-HPLC). PAA was derivatized by oxidation of methyl tolyl sulfide (MTS) into methyl tolyl sulfoxide (MTSO) detected by ultraviolet (UV) absorbance at 230 nm. The technique has a sensitivity of 0.3 microg x L(-1) and was highly specific. Results showed that pH measurements remain constant and demonstrated the absence of PAA permeation, which was confirmed by the absence of AA permeation regardless of the brand tested, with both unwrapped and overwrapped infusion bags, when flash sterilization is applied. These results allow flash sterilization to be performed with unwrapped infusion bags without any risk of drug degradation by PAA. This makes compounding safer and easier, which improves productivity.  相似文献   
45.
Synchronous rectovaginal, urinary bladder, and pulmonary endometriosis.   总被引:2,自引:0,他引:2  
BACKGROUND: Extragenital endometriosis is an uncommon condition that can affect almost any organ system and tissue in the human body. Disease involving multiple distant sites is extremely uncommon. METHODS: We report a rare case of synchronous rectovaginal, urinary bladder, and pulmonary endometriosis. We performed a Medline literature search using keywords "endom etriosis," "recto vaginal," "pulmonary," "bladder," "ureteral," "bowel," "extrapelvic," and "extragenital" and were unable to find any prior case reports of such findings. A 31-year-old female presented with catamenial dysuria of 1-year duration, pleurisy associated with spontaneous pneumothoraces of 7 months' duration and a long-standing history of pelvic pain. A multispecialty team with experience in endoscopic techniques was assembled, consisting of a thoracic, a urologic, and a gynecologic surgeon. Video-assisted thoracoscopic surgery with fulguration of all visible pleural endometriosis and pleurodesis was performed, followed by laparoscopic segmental bladder wall endometrioma excision and resection of rectovaginal endometriosis. Twelve months after surgery and without additional hormonal treatment, the patient is symptom free. CONCLUSION: Extragenital endometriosis may coexist in multiple sites. A high index of suspicion aids in the diagnosis. A multidisciplinary approach in a tertiary center, followed by appropriate surgical eradication of visible disease, can successfully treat endometriosis even in such extreme cases.  相似文献   
46.
Sleep is the main behavioral state of the premature infant. In adult intensive care units, sleep deprivation has been reported as one of the major stressors. Developmental care (DC) aims to decrease stressful events in neonatal intensive care unit and support well-being. AIM: To assess whether DC is accompanied by changes in sleep in preterm neonates. METHODS: A prospective cross-over study included 33 preterm neonates [mean (S.D.): gestational age: 29.3 (1.8) weeks; birth weight: 1245 (336) g]. Polysomnography was performed in two randomly ordered 3-h periods with and without DC. A blinded electrophysiologist analyzed sleep. The total sleep time (TST) was the primary outcome, duration of active (AS), quiet (QS) and indeterminate sleep, and latency before sleep were the secondary outcomes. Non-parametric Wilcoxon tests and ANOVA were used. RESULTS: In DC condition vs. control: TST increased [in minutes, mean (S.E.M.): 156.2 (2.9) vs. 139.2 (4.6), p=0.002], with increase in AS [86.6 (3.7) vs. 77.0 (4.2), p=0.024] and in QS [47.1 (4.1) vs. 36.9 (4.2), p=0.015], and sleeping latency decreased (2.1 (0.7) vs. 10.5 (2.0), p=0.0005]. CONCLUSION: DC promoted sleep in our study. The impact of DC on the neuro-behavioral outcome needs futures studies.  相似文献   
47.
This study aims to characterize the pharmacokinetics of mycophenolic acid (MPA) and its glucuronide metabolite (mycophenolic acid 7-O-glucuronide, MPAG) following single oral administration of enteric-coated mycophenolate sodium (EC-MPS, myfortic) at an approximate dose level of 450 mg/m(2) body surface area (BSA) to 25 stable renal transplant recipients (aged 5-16 yr), and to evaluate the safety and tolerability of EC-MPS in this pediatric population. Patients had been maintained on a cyclosporine emulsion, Neoral-based immunosuppressive regimen for at least 3 months and had received their first or second renal transplant more than 6 months prior to entry into the study. After a brief lag phase (t(lag) 0.75 h), MPA was rapidly absorbed (t(max) 2.5 h) and rapidly converted to MPAG (t(max) 3.25 h), with relatively high plasma concentrations of MPAG (C(max) 67.7 microg/mL) compared with MPA (C(max) 36.3 microg/mL). The elimination half-life for MPAG was slightly longer than for MPA (approximately 13 h vs. 8.5 h), and the apparent oral clearance of MPA was approximately 0.2 L/h/kg. The pharmacokinetics of MPA or MPAG were not affected by age, body weight or BSA, within the study population. The pharmacokinetic results for pediatric patients are comparable with those obtained previously in adults, although exposure based on AUC(0-infinity) was approximately 23% higher, and this finding may be a result of dosing on the basis of BSA, rather than body weight. The recommended dose of EC-MPS in pediatric patients is 400-450 mg/m(2) twice daily or, alternatively, approximately 10-14 mg/kg twice daily when used in combination with cyclosporine microemulsion.  相似文献   
48.
A long duration of acute retroviral syndrome (ARS) and a short incubation of ARS (IncARS) are independent predictors of a fast progression to AIDS. The first objective of this study was to validate previous estimates of IncARS by comparing durations between health care workers (HCWs) accidentally infected by HIV and individuals infected by other routes (non-health care workers [N-HCWs]). The second objective was to use parametric survival models to generate hypotheses on various steps occurring during the IncARS. Data from a prospective cohort of patients with documented ARS and from individuals with ARS as the result of accidental exposure to HIV were analyzed. Nonparametric and parametric survival models were used to describe the incubation of ARS. No differences were found for the median IncARS between 34 HCWs (21.5 days) and 70 N-HCWs (21.5 days) (log-rank test, P = 0.72). According to survival models, IncARS can be modeled with a gamma and/or lognormal model with means of 26.4 days and 26.7 days, respectively. The gamma model suggests that 3 sequential stages are present during the IncARS, which is compatible with basic science investigations identifying crossing of the epithelial barrier by the virus, the virus-host cell interactions, and the viral systemic dissemination.  相似文献   
49.
50.
BACKGROUND: The disappearance of anti-HCV antibodies over time, after a self-limited infection, also referenced seroreversion, has been observed. The frequency of this phenomenon remains controversial, especially in immunocompetent subjects. However, it has important implications in the context of transfusion inquiries, in particular in case of a blood donor suspected to have transmitted HCV through a past blood donation. STUDY DESIGN AND METHODS: Our findings are presented of a longitudinal study, including 16 patients from a cohort of 78 immunocompetent, multitransfused individuals who were positive for anti-HCV (EIA and confirmatory assay [RIBA]) and followed over a long period of time without having received any antiviral therapy. The aim was to establish whether a past and self-resolved HCV infection could evolve toward a negative serology. RESULTS: The 16 patients were classified in three groups: 1) 12 patients who remained anti-HCV positive with no evolution in their RIBA pattern after a mean follow-up of 7.6 years; 2) one patient who presented a complete seroreversion 6 years after enrollment; and 3) three patients with a partial seroreversion over a mean follow-up of 16 years. CONCLUSION: HCV infection is not always characterized by a persistent antibody response, even in immunocompetent individuals. This should be taken into consideration when transfusion inquiries are conducted.  相似文献   
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