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Transplant arteriosclerosis in a rat aortic model.   总被引:6,自引:1,他引:5       下载免费PDF全文
Transplant arteriosclerosis (TA) has emerged as an obstacle to the long-term survival of transplanted organs, especially cardiac transplants. The animal models that have been used to study TA have not been fully characterized with regard to features such as the time course of cell proliferation and the sequence of cell types arriving in the developing intimal lesion. We present a model of TA based on a transplanted segment of abdominal aorta that helps address these questions. Two strains of rats (PVG x DA) underwent orthotopic aortic transplantation without immunosuppression and were killed at 14, 20, 40, and 60 days after transplantation. The within-strain control group displayed minimal evidence of cellular rejection with minimal to absent intimal lesions. In contrast, the allograft group showed a linearly increasing intimal lesion, up through 60 days after transplantation. The mechanism of intimal thickening was by an increase in cell number at the earlier time points with the later deposition of extracellular matrix. The early intimal lesion consisted mostly of mononuclear inflammatory cells (45%) with gradually increasing presence of smooth muscle cells (SMC) in the intima between 20 and 60 days. Conversely, the media showed gradual infiltration by macrophage-type cells with virtual loss of all SMC from the media by 40 days. The proliferative index showed a peak of 6% and 8% at 20 days in both the intima and media, respectively, and was preceded by the presence of macrophages. In fact, most of the proliferating cells at the earlier time points were either monocytes/macrophages, or were immediately adjacent to monocyte-/macrophage-rich regions. This straight artery segment model of transplant arteriosclerosis provides an easily quantifiable system in which the effects of different interventions (e.g., immunosuppressive regimens) can be tested.  相似文献   
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To evaluate the possible effect of pentoxifylline on the acrosomereaction (AR) and its correlation with in-vitro fertilization(IVF), sperm samples obtained from 51 patients who underwentIVF treatment were studied. Acrosome reactions were evaluatedas spontaneous, pentoxifylline-treated and calcium ionophore(A23187) induced, before and after treatment. The correlationof AR with fertilization in vitro in spermatozoa pre-treatedwith pentoxifylline was sought. In cases with failure or verylow fertilization rate (10%) in their previous trials, spermatozoaafter swim-up were treated before insemination. Spontaneousacrosome loss remained low even after treatment (mean ±SD: 8.18 ± 1.74%). Response to A23187 was enhanced significantly(P < 0.001) by pre-treatment with pentoxifylline in 33 controlcases (group A) in which fertilization in vitro was previouslysuccessful without this treatment. Patients with at least twoepisodes of failed fertilization were divided into two groups.In 11 cases (group B), the IVF rate was improved significantly(P < 0.001) by the treatment. This was not observed in sevencases (group C) in which the treatment induced no increase inIVF rate. We achieved nine (27.3%) pregnancies in group A andfive (45.4%) pregnancies in group B. This study demonstratedthat pentoxifylline enhanced A23187 induced the acrosome reactionand this effect was correlated with improvement in IVF rate.  相似文献   
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A rare cause of acute visual loss due to a chiasmal cavernous malformation is presented. Acute visual loss was due to local hemorrhage and volume expansion of the cavernous malformation inside and outside of the optic chiasma. This unique location of cavernous malformation is associated with a risk of permanent loss of the vision. Cavernous malformations of optic chiasma should be carefully evaluated and considered for possible preventative surgical resection before it becomes symptomatic.  相似文献   
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BACKGROUND: Mumps vaccine has not yet been included in the routine vaccination programme, for this reason mumps is still one of the most common infections for children in Turkey. One of the major complication of mumps is meningoencephalitis, which although usually heals spontaneously, it may cause neurologic complications. METHODS: This study was undertaken to investigate epidemiologic and demographic characteristics in children with mumps and mumps meningoencephalitis and clinical/laboratory findings in children with mumps meningoencephalitis diagnosed over a 11 year period. A total of 2422 mumps and 135 mumps meningoencephalitis cases were covered in this study which constitutes one of the largest series of mumps meningoencephalitis in the literature. The mean age of mumps and mumps meningoencephalitis cases were 6.6 +/- 2.7 and 7.6 +/- 2.6 years, respectively. RESULTS: There was a male predominance both among the cases of mumps and mumps meningoencephalitis. The age and seasonal distributions were similar in the mumps and mumps meningoencephalitis groups. The most common symptoms of mumps meningoencephalitis were fever (97%), vomiting (94%) and headache (88.8%). The mean cerebrospinal fluid (CSF) total cell count and lymphocyte count were 540 +/- 460/mm(3) and 300 +/- 330/mm(3), respectively. The mean CSF protein and glucose levels were found to be 56.97 +/- 27.94 mg/dL and 53.67 +/- 15.46 mg/dL, respectively. The mean of CSF/blood glucose ratio was 0.53 +/- 0.16. The mean duration of hospitalization in mumps meningoencephalitis cases was found to be 5.1 +/- 2.4 days and this was longer in boys (P < 0.05). CONCLUSION: In patients with mumps meningoencephalitis, higher CSF protein levels and lower CSF glucose/blood glucose ratio were associated with longer hospitalization periods. There was no death.  相似文献   
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Aim: In this population‐based study, we aimed to determine the total sleep duration (TSD), its association with socio‐economic status (SES) and behavioural symptoms among schoolchildren. Methods: A cross‐sectional study was performed among schoolchildren in Istanbul. A structured questionnaire evaluating the sleep schedule variables was filled out by their parents. SES was determined according to the Turkish SES scale. Results:  The mean age of 2669 children was 8.2 ± 2.4 years, and 51% of the students were girls. The mean TSD was 10.20 ± 1.04, and the mean bedtime was 21.57 ± 0.56 (both in hours, minutes ± SD). Boys tended to go bed later (p = 0.004) and slept less than girls (p = 0.02). The duration of sleep disruptions increased (p < 0.001), whereas TSD decreased with age (p < 0.001). Multiple linear regression revealed that waking time and TSD decreased significantly (p < 0.05) with higher SES among both girls and boys. Sleep fragmentation was associated with habitual snoring, parasomnias, daytime sleepiness and conduct symptoms. Conclusion: Decreased total sleep duration is more prominent in boys, older children and children among higher socio‐economic status. Insufficient sleep attributed to shortened total sleep duration by age and higher socio‐economic status might have a negative effect on both sleep hygiene and psychological well‐being in schoolchildren.  相似文献   
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A remediable cause of poor treatment response in drug‐susceptible tuberculosis (TB) patients may be low plasma levels of one or more of the first‐line anti‐TB drugs. The aim of this work was to develop an accurate and precise LC‐MS/MS method for simultaneous quantification of all four first‐line anti‐TB drugs in plasma suitable for therapeutic drug monitoring (TDM). To adjust for degradation and losses during sample preparation, isotopically labeled compounds were used as internal standards. Plasma samples spiked with internal standards were extracted using protein precipitation with methanol and acetonitrile. Simultaneous separation of all four drugs was accomplished with a Chromolith Reversed‐Phase column and mobile phases consisting of water, methanol, ammonium acetate and formic acid with subsequent mass spectrometric quantification. The linear range of the calibration curve for isoniazid was 0.5–10 mg/L, for rifampicin 0.75–30 mg/L, for ethambutol 0.25–10 mg/L and for pyrazinamide 4–80 mg/L. The lower limit of quantification was 0.5 mg/L, 0.75 mg/L, 0.25 mg/L and 4.0 mg/L, respectively. Precision estimated by the coefficient of variation was <15% for all four drugs. The LC‐MS/MS method can readily be used for simultaneous quantification of first‐line anti‐TB drugs in plasma and is well suited for TDM.  相似文献   
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