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1.
BACKGROUND: Classification of patients with chronic whiplash associated disorders (WAD) into homogenous subgroups is an important objective in order to tailor interventions and to control for subgroup differences when evaluating treatment outcome. AIMS: The aims of this study were to investigate if it was possible to replicate and describe the three cluster solution and profiles found in other pain groups and describe cluster profiles based on self-reported Multidimensional Pain Inventory-scores for patients with WAD three months after the injury, describe characteristics of the clusters in relation to disability, self-efficacy and coping at the same point in time and to validate the cluster solution by comparing clusters in disability, self-efficacy and coping over time. METHODS: Ninety-one WAD-patients three months after the accident took part in the study. The measures used were the Multidimensional Pain Inventory-Swedish version (MPI-S), The Self-Efficacy Scale, The Coping Strategies Questionnaire and The Pain Disability Index. Cluster analysis was conducted for the total sample MPI-S subscale scores. RESULTS: The adaptive copers cluster represented 42% of the sample, dysfunctional 34% of the sample, and interpersonally distressed 24% of the sample. The external validation of cluster solution showed that there were several significant differences between clusters in self-efficacy, disability and coping measures. There was also a significant interaction effect (clusterxtime) in disability (PDI). Patients in dysfunctional cluster reported a decreased disability over time. CONCLUSIONS: These results support the presence of different subgroups among patients with whiplash associated disorders. This classification can be seen as a complement to a classification based on medical condition.  相似文献   
2.
The assessment of mechanical ventilator performance is a complex task requiring measurement of a number of different transducers under a variety of conditions. The use of dedicated testing equipment can alleviate the complexity of the experimental apparatus. This paper assesses the accuracy and versatility of the Biotek VT-1 and VT-2 dedicated ventilator testers. Results show that the testers perform within the manufacturer's specifications and have the required flexibility to be used in investigating faults reported with ventilators.  相似文献   
3.
Summary The shells ofLymnaea truncatula infected with the larval stages ofFasciola hepatica were significantly longer than those of comparable uninfected controls. The dry mass (tissue, shell+parasite) of the same infected snails, 56 days after infection, was approximately twice that of the controls (tissue+shell). The increased mass of infected snails was not due to a disproportionate increase in shell weight relative to tissues.Infected snails maintained at 20°C had virtually ceased egg production by 21 days post-infection whereas control snails continued to lay eggs steadily for the duration of the experiment.The dry mass of snail tissue plus the cumulative dry weight of eggs produced was taken as an indication of the ability of control snails to generate biomass. Similarly the tissue mass plus cumulative egg weight and parasite weight was taken as an indication of the ability of the infected snails to generate biomass. The control and infected snails were not significantly different in this respect indicating that the gigantism of infected snails could be the result of a switch in nutrient supply from reproduction to somatic tissue growth and parasite growth.Castration was brought about 17–21 days after infection as a result of the direct consumption of the ovotestis by a proportion of the redial population.In a separate experiment it was demonstrated that a population of infected snails maintained at 20°C survived as long as a similar group of control snails.The findings with this host-parasite system are discussed in relation to possible mechanisms causing castration and gigantism in other digene-snail interactions, and in relation to parasitic castration in other groups. It is concluded that the observed gigantism of infected snails is more likely to have a nutritional rather than endocrine origin.Based on a paper presented at Molluscs as Intermediate Hosts, Symposium of the German Society of Parasitology, Würzburg, 4–7 April, 1979  相似文献   
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5.
PURPOSE: To describe the imaging and histologic features of large-core needle biopsy (LCNB) specimens of fibrous nodules. MATERIALS AND METHODS: Of 853 breast masses in which LCNB was performed, 38 (4%) revealed histologic findings of fibrous nodules. Repeat biopsy was performed in 16 lesions (surgical excision, 13 lesions; repeat LCNB, three lesions). The mammographic and ultrasonographic findings in these 16 cases, the histologic LCNB findings, and the repeat biopsy findings were retrospectively reviewed. RESULTS: Repeat biopsy findings confirmed the diagnosis of fibrous nodules in 15 of the 16 masses. In one mass, repeat LCNB findings showed a fibroadenoma. The imaging features of the fibrous nodules varied. Five nodules (33%) manifested as masses with indistinct margins; six (40%), as circumscribed masses. In four cases (27%), imaging suggested malignancy. None were calcified masses. An additional 22 masses had circumscribed or indistinct borders and were diagnosed with LCNB as fibrous nodules. None of these masses had suspicious findings, and repeat biopsy was not performed. CONCLUSION: Fibrous nodules usually manifest as masses with circumscribed or indistinct margins but can have findings suggestive of malignancy. LCNB can reveal histologic findings consistent with this diagnosis. In all masses in which repeat biopsy was performed, the diagnosis of a fibrous nodule was confirmed or another benign stromal lesion was diagnosed.  相似文献   
6.
Summary The disposition of cisplatin was evaluated in 28 children and adolescents with cancer, as part of a phase II clinical trial. Patients received either 30 mg/m2 (11) or 90 mg/m2 (17) of cisplatin as a 6-h IV infusion. Serum samples and divided urine collections were obtained over 48 h following completion of the cisplatin infusion, and were assayed in duplicate for total platinum by atomic absorption spectrophotometry. Serum samples obtained up to 4 h after three cisplatin infusions were assayed for parent (free) cisplatin following ultrafiltration. The mean (±SE) elimination half-life of free cisplatin in serum was 1.3 (±0.4) h. Serial serum concentrations of total platinum following 90 mg/m2 dosages were adequately described by a biexponential equation. The mean (±SE) serum T1/2 of total platinum was 0.42 (±0.10) h and the mean (±SE) T1/2 was 44.43 (±8.24) h. The intercompartment distribution rate constants of a two-compartment kinetic model indicate extensive tissue accumulation of total platinum, with a rate of transport into tissue compartments (K12) that is about six times the rate of transport out of tissues (K21). The mean (±SE) renal clearance of total platinum from 0–3 h was 37.36 (±11.96) ml/min/m2 and 35.8 (±13.6) ml/min/m2 for the 30 mg/m2 and 90 mg/m2 groups, respectively. This value decreased to 3.25 (±0.94) and 2.16 (±0.4) ml/min/m2 for the two groups by the 6–12 h interval, and remained between 1 and 3 ml/min/m2 for the duration of the observation period. The ratio of total plantinum clearance to creatinine clearance decreased significantly(P<0.05) beginning 3 h post-infusion. The change in renal clearance of total platinum is apparently a function of two independent first-order processes for renal clearance of parent drug and cisplatin metabolites.  相似文献   
7.
BACKGROUND: The purpose of the present study was to document the value of an implanted multichannel neuroprosthesis (Freehand System) for restoring hand grasp in the first Australians to receive this device. METHODS: Hand function in C5 quadriplegic patients was assessed via measurement of pinch forces, a grasp release test and tests of activities of daily living (ADL). Comparisons were made between presurgery scores and scores recorded after rehabilitation when the neuroprosthesis was and was not in use. RESULTS: A significant difference for both lateral pinch (P = 0.003) and palmar grasp (P = 0.003) was found between forces recorded with and without the use of the neuroprosthesis after rehabilitation, but not between forces recorded presurgery and during rehabilitation without the neuroprosthesis. All subjects were able to grasp, move and release more objects within the 30-s test period with the neuroprosthesis than without it. Collective results for the eight ADL tests for all six subjects show that, in 35 of the 48 (73%) occasions, less physical assistance and/or adaptive equipment was required when the Freehand system was employed compared to when it was not used. In 41 of the 48 (85%) occasions, the six subjects expressed a preference for using the neuroprosthesis to perform these activities of daily living. Twelve months after rehabilitation, five of the six subjects still used the neuroprosthesis daily or every second day. CONCLUSION: The Freehand neuroprosthesis has provided useful hand function with few surgical and technical difficulties in these patients. Regular ongoing use of the device indicates user satisfaction.  相似文献   
8.
Understanding the forces underpinning female genital mutilation/ cutting (FGM/C) is a necessary first step to prevent the continuation of a practice that is associated with health complications and human rights violations. To this end, a systematic review of 21 studies was conducted. Based on this review, the authors reveal six key factors that underpin FGM/C: cultural tradition, sexual morals, marriageability, religion, health benefits, and male sexual enjoyment. There were four key factors perceived to hinder FGM/C: health consequences, it is not a religious requirement, it is illegal, and the host society discourse rejects FGM/C. The results show that FGM/C appears to be a tradition in transition.  相似文献   
9.
Fetal RBCs are produced during a period of very rapid growth and stimulated erythropoiesis under hypoxic intrauterine conditions. Fetal RBC life span varies with gestational age (GA) and is shorter than that in healthy adults. Due to the special kinetic properties of life span-based survival of human RBCs, a mathematical model-based kinetic analysis of the survival of fetal RBCs shortly after birth provides a unique opportunity to “look backward in time” to evaluate fetal erythropoiesis. This work introduces a novel method that utilizes postnatal in vivo RBC survival data collected within 2 days after birth to study both nonsteady-state (non-SS) in utero RBC production and changing fetal RBC life span over time. The effect of changes in erythropoiesis rate and RBC life span and the effect of multiple postnatal phlebotomies on the RBC survival curves were investigated using model-based simulations. This mathematical model, which considers both changes in the rate of erythropoiesis and RBC life span and which accurately accounts for the confounding effect of multiple phlebotomies, was applied to survival curves for biotin-labeled RBCs from ten anemic very low birth weight preterm infants. The estimated mean fetal RBC production rate scaled by body weight was 1.07 × 107 RBCs/day g, and the mean RBC life span at birth was 52.1 days; these values are consistent with reported values. The in utero RBC life span increased at a rate of 0.51 days per day of gestation. We conclude that the proposed mathematical model and its implementation provide a flexible framework to study in utero non-SS fetal erythropoiesis in newborn infants.KEY WORDS: cord blood RBCs, fetal erythropoiesis, fetal RBC life span, fetal RBC production, red blood cells  相似文献   
10.
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