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Endocrine tumors of the ileum. Cytochemical and clinical aspects   总被引:2,自引:0,他引:2  
Sixteen patients with endocrine ileal tumors and liver metastases were analyzed with regard to the size, multicentricity, and growth pattern of the primary tumor, the occurrence of carcinoid syndrome, as well as the concentrations of serotonin and substance P (SP) in blood, 5-hydroxy-indole-acetic acid (5-HIAA) in urine, and the course of the disease. Excised specimens from the tumors were immediately processed for immunocytochemical investigations of the presence of neurohormonal peptides, using a broad spectrum of antisera and optimal histoprocessing techniques. In all patients the serotonin levels in blood and/or the 5-HIAA in urine were high. The SP concentration in plasma was markedly elevated in all but two of the ten patients investigated in this respect. A mixed growth pattern prevailed in the tumors of 7 patients with fatal disease. Serotonin cells were found in all tumors and SP-immunoreactive tumor cells in all but one; one of the carcinoids also contained a few tumor cells displaying enkephalin immunoreactivity. In conventionally fixed and paraffin embedded specimens of the same tumors usually no immunoreactive tumor cells at all could be demonstrated, showing that SP is among the peptides vulnerable to poor histotechniques. Nevertheless, SP, together with serotonin, constitute reliable clinical tumor markers for ileal carcinoids.  相似文献   
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Background: The transport mobility of children and adolescents with cerebral palsy (CP) is of vital interest for the individual, as well as for society. Enhanced transport mobility can be related to improved functional health status and a higher degree of autonomy, which in turn may reduce the demand for societal support. UN Resolution 48/96, together with Swedish legislation and ''Vision Zero'' have in different ways established that the transport system must be designed to meet also the needs of children and adolescents with disabilities. Hence, it is necessary to identify and eliminate obstacles hindering children and adolescents with CP from using public transport and other means of transport, such as their own cars, at the same level as other members of society. However, in the case of children and adolescents with CP, the transport situation and the learner driver's educational situation have so far been largely unknown. Aim: The general aim of the thesis was to describe and analyse, from a legislative and a public health perspective, the transport mobility situation for children and adolescents with CP. Furthermore, the general aim was to identify obstacles for the target group to use public transport and other means of transportation, at the same level as other members of the society, and to suggest improvements that will remove the identified obstacles. Material and methods: Several different data collection methods were used. Data, concerning travel habits and parents' perceived risks regarding transportation, were taken from a postal questionnaire addressed to parents of children and adolescents with CP. In order to estimate the numbers of potential learner drivers with CP in each age group in Sweden, a literature review was conducted, based on Swedish material. Furthermore, logbooks for learner drivers with CP were analysed retrospectively, in order to identify procedures, problems and key tasks in their driver education. Visual search strategies for learner drivers with CP were analysed, utilizing an eye tracker, and an attempt was made to introduce a screening tool for predicting the outcome of driver education. Results: Children and adolescents with CP were found to be transported under unsafe conditions, causing worry among their parents. When transporting children in the family vehicle, the parents were exposed to a very heavy burden, which increased their worry. The prevalence of potential learner drivers with CP who were in need of highly specialised driver education, including individually adapted driver training vehicles, was estimated to be 0.15 per 1,000 of a population-based age group of learner drivers in Sweden. Complex procedures, structural problems and financial obstacles made it difficult for adolescents with CP to obtain a driving licence and an adapted vehicle. The total duration of the driving tuition given by a driving instructor was found to be almost nine times higher for learner drivers with CP than for non-disabled learner drivers. Visual search strategies among learner drivers with CP were found to be less flexible than among other learner drivers. This fact indicated a need for better methods of teaching such strategies to this group as an integral component of their driver education. The validity of the motor-free visual perceptual test, TVPS-UL, for predicting the outcome of driver education for learner drivers, was found to be low. In order to find a reliable and valid screening tool for this purpose, future studies should focus on cross-validation of visual perceptual and dual task performance tests for different types of independent variables, such as obtaining a driving licence or not, accident involvement and driving ability. Conclusion: The transport system was found, from a legislative and public health perspective, to be unsuitable to meet the needs of children and adolescents with CP. Suggestions for improving transport mobility for children and adolescents with CP are provided. Several of these suggestions are practical, concrete and contextual for Swedish conditions, and some of them necessitate future research. However, a number of these suggestions are also applicable in an international context.  相似文献   
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Background: The Calibrated Automated Thrombography (CAT) is an in vitro thrombin generation (TG) assay that holds promise as a valuable tool within clinical diagnostics. However, the technique has a considerable analytical variation, and we therefore, investigated the analytical and between-subject variation of CAT systematically. Moreover, we assess the application of an internal standard for normalization to diminish variation.

Methods: 20 healthy volunteers donated one blood sample which was subsequently centrifuged, aliquoted and stored at ?80?°C prior to analysis. The analytical variation was determined on eight runs, where plasma from the same seven volunteers was processed in triplicates, and for the between-subject variation, TG analysis was performed on plasma from all 20 volunteers. The trigger reagents used for the TG assays included both PPP reagent containing 5?pM tissue factor (TF) and PPPlow with 1?pM TF. Plasma, drawn from a single donor, was applied to all plates as an internal standard for each TG analysis, which subsequently was used for normalization.

Results: The total analytical variation for TG analysis performed with PPPlow reagent is 3–14% and 9–13% for PPP reagent. This variation can be minimally reduced by using an internal standard but mainly for ETP (endogenous thrombin potential). The between-subject variation is higher when using PPPlow than PPP and this variation is considerable higher than the analytical variation.

Conclusion: TG has a rather high inherent analytical variation but considerable lower than the between-subject variation when using PPPlow as reagent.  相似文献   
6.
The frontal ganglion of the adult forms of the tobacco hornworm, Manduca sexta, was investigated immunocytochemically for the occurrence of the gastro-entero-pancreatic (GEP) neurohormonal peptides, namely insulin, nerve growth factor, epidermal growth factor, insulin C-peptide, somatostatin, glucagon, glicentin, pancreatic polypeptide (PP), polypeptide YY (PYY), secretin, vasoactive intestinal peptide (VIP), gastric inhibitory peptide (GIP), gastrin, cholecystokinin (CCK), enkephalin, alpha- and beta-endorphins, substance P, neurotensin, bombesin, motilin, ACTH, serotonin, and calcitonin. Among all the antisera tested, positive immunostaining was obtained with anti-insulin B-chain serum only. The insulin B-chain immunoreactivity was localized in 4-6 large (30-40 microns) neurons, in the neuropile, and in the recurrent nerve. It is speculated that the insulin-like immunoreactive material may be transported to the neurohaemal organ (corpora cardiaca) through the nervi cardiaco-somatogastrici.  相似文献   
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Improved prognostication in small (pT1) breast cancers by image cytometry   总被引:1,自引:0,他引:1  
Summary Feulgen-stained samples from 460 small (pT1) primary breast cancers were investigated by means of an image analysis system. Several DNA, morphometrical and textural parameters were evaluated for each patient, and the prognostic meaning of these parameters was then investigated by the Cox regression analysis. As prognostic criterion a distant recurrence-free survival of five years was considered.All investigated DNA- and morphometrical parameters as well as several textural parameters showed a significant univariate correlation with the clinical course. In a multivariate approach the axillary nodal status was the most important prognostic parameter, followed by a morphometric parameter (anisokaryosis) and two textural parameters (runlength and co-occurrence). None of the DNA histogram derived parameters could add prognostic information in this multivariate approach. By the linear combination of the four selected variables, an individual prognostic factor was calculated. Using this factor the patients could be split into several groups according to their risk for distant metastases. Thus a low risk group of pT1 patients could be identified with a distant recurrence rate of only 2% after 5 years, and also a group of patients with a considerably worse prognosis and a 5-year distant recurrence rate of 53%. In contrast, using the nodal status as single parameter allows the identification of a low risk group of patients (pN0pT1) with a disant recurrence rate of 10.6%. Therefore, morphometrical and textural parameters can provide powerful prognostic information in small breast carcinomas and may allow a better selection of patients for adjuvant therapy.  相似文献   
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