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11.
X-linked congenital stationary night blindness (CSNBX) is anon-progressive retinal disorder characterized by decreasedvisual acuity and loss of night vision. CSNBX Is clinicallyheterogeneous with respect to the involvement of retinal rodsand/or cones in the disease. in this study, we localize a newlocus for CSNBX to Xp21.1, thus providing evidence that CSNBXis also genetically heterogeneous. A clear correlation betweendifferent genotypes and phenotypes cannot be found yet. Thenew CSNBX gene described here is closely linked to the X-linkedretinitis pigmentosa type 3 gene region, which supports thehypothesis that there may be a functional relationship betweencongenital stationary night blindness and retinitis pigmentosa.  相似文献   
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BACKGROUND: Affect regulation is assumed to be a biologically based function that can become disrupted by inadequate parenting and by traumatic experiences. We studied the relation between the perceived parental parenting style, and sexual and physical abuse, with alexithymia, dissociation, anxiety and depression. METHODS: In a cross-sectional study psychiatric outpatients were administered a structured interview on childhood physical and sexual abuse and they completed a number of questionnaires about the parenting styles of their parents, and about alexithymia, dissociation and mood pathology. RESULTS: Maternal and paternal parenting styles were moderately correlated with alexithymia and depression. The paternal parenting style was also correlated with dissociation. Optimal parenting of one of the parents had a buffering effect on the degree of alexithymia, but not on the severity of other forms of affect dysregulation. The effect of sexual or physical abuse did not add to that of parental parenting style in terms of predicting affect dysregulation. However, a positively perceived maternal parenting style was found to have a buffering effect in terms of the degree of alexithymia, if sexual abuse had also taken place. CONCLUSIONS: Perceived parenting does appear to be of some significance in the development of alexithymia. Optimal parenting of one of the parents may protect against the development of alexithymia when the parenting of the other parent is perceived as non-optimal. However, it is likely that other factors besides parental care and sexual or physical abuse play an important role in the development of an adequate affect regulation.  相似文献   
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Pseudoxanthoma elasticum (PXE) is a heritable systemic disorder characterized by calcification of the elastic fibers of the connective tissue. Symptoms are predominantly noted in the eye, the skin, and the cardiovascular system, resulting in visual loss, skin lesions, and life-threatening vascular disease. In this study we combined homozygosity mapping and genome scanning with 374 markers in affected individuals from a PXE family from a genetically isolated population in The Netherlands. Initial homozygosity in two or three patients was found with up to 20 markers, among which D16S292 located in 16p13.1. Upon refined and more extensive family screening of the latter region, close linkage without recombination was found with the marker D16S764 (Zmax=6.27). Despite clear autosomal recessive inheritance of the ocular symptoms in PXE, vascular symptoms appear in 40%–50% of the heterozygotes.  相似文献   
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Summary The eight largest double-stranded (ds) RNA genome segments of Epizootic haemorrhagic disease virus (EHDV) serotype 2 (Alberta strain) have been cloned. Of these, segments 4, 5, 6, 7, and 8 are represented by clones that correspond in size to those predicted for full-length clones. The different clones were used as nucleic acid probes to study the nucleic acid homology of cognate genes of four different EHDV serotypes. The results indicated that the 4 isolates may be subdivided in two geographic groups which include Ibaraki virus as the sole member of one group and EHDV1 (New Jersey), EHDV2 (Alberta) and EHDV6 (XBM67—isolated in South Africa) as a second. Genome segments 1, 3, 4, 6, and 8 were found to be highly conserved with more than 90% homology amongst cognate genes of three of the members of the EHDV serogroup. Of these, segments 1 and 3 showed the largest degree of homology with cognate genes of members of the BTV serogroup. Segment 6 and 8 probes of EHDV2 (Alberta) on the other hand did not hybridize with BTV dsRNA under conditions of moderate to low stringency and are recommended for use as EHDV group-specific probes.  相似文献   
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Automatic decomposition electromyography (ADEMG) is a commercially available software package with installed reference values that enables the objective measurement of motor unit action potentials (MUAPs). To assess the diagnostic yield of this package in idiopathic inflammatory myopathies (IIM) we performed biceps brachii ADEMG in 17 patients with polymyositis, dermatomyositis and inclusion body myositis. Results were compared with those in 12 controls, and with the results of conventional EMG of the biceps and other muscles. Decreased mean values for MUAP duration occurred significantly more frequently in IIM patients than in controls; other MUAP characteristics did not differ. In IIM patients, decreased mean amplitude and increased mean number of turns occurred significantly less frequently on ADEMG than did corresponding abnormalities on conventional biceps EMG. Decreased mean values for duration and amplitude, and increased mean values for number of turns were seen significantly less often on ADEMG than corresponding abnormalities on conventional EMG of four different, individually chosen muscles. Overall evaluation of ADEMG resulted in a diagnosis of possible myopathy in 1 and probable myopathy in 8 patients, whereas overall evaluation of conventional EMG led to a diagnosis suggestive of IIM in 13 patients. We conclude that, although measurement of mean MUAP duration might be valuable in IIM diagnosis, our results do not favour the use of biceps brachii ADEMG and the installed reference values for the diagnosis of IIM. We suggest modifications to improve ADEMG's applicability.  相似文献   
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Background: After renal transplantation, early graft function (EGF) can be divided into delayed graft function (DGF), slow graft function (SGF) and immediate graft function (IGF). DGF is well documented. However, when evaluating the long-term significance of early function, the literature shows conflicting definitions and inconsistent results. In addition, SGF, a new entity separate to DGF and IGF, is a recent and poorly understood development. Aim: To investigate the risk factors for and the impact of poor EGF (PEGF) on long-term outcome. Methods: This retrospective study reviewed the records of local adult patients who underwent renal transplantation at the Groote Schuur Hospital (Cape Town, South Africa) between 2004 and 2008. EGF was divided according to day 5 serum creatinine into IGF (serum creatinine <150 μmol/l), SGF (serum creatinine >150 but <450 μmol/l) and DGF (serum creatinine >450 μmol/l or dialysis in the first week). DGF and SGF together comprised PEGF, with IGF alone representing good EGF (GEGF). Results: A total of 121 patients (77 men, 44 women; mean age 39 years, range 14-67) were included in the study. Eighteen were excluded due to nephrectomy (n = 8), death (n = 6) or loss to follow-up (n = 4) within the first year. Analysis of cadaveric donors showed no significant risk factors for PEGF with the exception of cold ischaemic time, which differed significantly between the GEGF and PEGF groups, with means of 12 and 16 h, respectively (p = 0.013). Considering both living and cadaveric grafts, the 1-year estimated glomerular filtration rate (eGFR) was significantly different between IGF and DGF (p = 0.038) as well as between IGF and SGF (p = 0.028), with no significant difference between SGF and DGF (p > 0.05). A comparison of the PEGF and GEGF groups yielded significantly different 1-year eGFR values (60 and 50 ml/min, respectively; p = 0.07), with PEGF also associated with a longer hospital stay (20 vs. 14 days; p = 0.00005). Acute rejection was independently associated with a lower 1-year eGFR (p = 0.028), but in the absence of rejection, GEGF and PEGF remained significantly different with regards to 1-year eGFR (p = 0.024). Conclusions: SGF is not related to IGF but rather to DGF and should thus be regarded as a form of PEGF as opposed to GEGF. PEGF has a worse long-term outcome, and this indicates the need for increased efforts in its prevention and greater attention to its management.  相似文献   
20.
We determined the effect of HIV infection on deaths among persons >18 months of age with culture-confirmed candidemia at 29 sentinel hospitals in South Africa during 2012–2017. Of 1,040 case-patients with documented HIV status and in-hospital survival data, 426 (41%) were HIV-seropositive. The in-hospital case-fatality rate was 54% (228/426) for HIV-seropositive participants and 37% (230/614) for HIV-seronegative participants (crude odds ratio [OR] 1.92, 95% CI 1.50–2.47; p<0.001). After adjusting for relevant confounders (n = 907), mortality rates were 1.89 (95% CI 1.38–2.60) times higher among HIV-seropositive participants than HIV-seronegative participants (p<0.001). Compared with HIV-seronegative persons, the stratum-specific adjusted mortality OR was higher among HIV-seropositive persons not managed in intensive care units (OR 2.27, 95% CI 1.47–3.52; p<0.001) than among persons who were (OR 1.56, 95% CI 1.00–2.43; p = 0.05). Outcomes among HIV-seropositive persons with candidemia might be improved with intensive care.  相似文献   
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