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Patient survival after renal transplantation; more than 25 years follow-up   总被引:9,自引:2,他引:7  
Background: The determinators of patient survival after renal transplantation are incompletely known, and conflicting results hae been reported. This may have been influenced by time-related changes in patients selection, post-transplantation management and immunosuppressive regimens. This study was performed to evaluate in recipients of a first renal transplant the effect of patient characteristics, transplantation era, and the immunosuppressive regimen on patient survival. Method: We studied data from the Leiden Renal Transplant Database of all first renal transplantations performed between 1966 and 1994 in Leiden, the Netherlands. The effect of the following parameters on mortality was investigated: era of transplantation, sex, age at transplantation, cause of renal failure, immunosuppressive regimen, type and duration of pretransplantation dialysis, hypertension, diabetes mellitus, and smoking. In addition we analysed the causes of death. Results were expressed as crude mortality rates, relative risks of mortality, and standardized mortality ratios as compared with death rates in the Dutch population. Results: The analysis comprised 86 living donor transplant recipients and 916 cadaver transplant recipients. After adjustment for age and sex, the relative risk of morality for living donor transplant recipients compared with cadaver transplant recipients was 0.5 (95% CI 0.2 to 10.3, P=0.06). In the first cadaver kidney transplant recipients the risk of first-year mortality improved significantly with time, which coincided with the introduction of cyclosporin. The risk of mortality after the first year was higher in patients aged over 40 years at transplantation, men, smokers, and in the presence of hypertension or diabetes, but the effect of individual factors on mortality was small. We found no effect of the type of pretransplantation dialysis or the duration of pretransplantation haemodialysis on post-transplantation mortality. The standardized mortality ratio for recipients of first renal transplants was 14 times the population average in the first year after transplantation and was still four times in the remaining years. Conclusion: In the present study, time-related changes in patient management were responsible for improved patient survival in the first year after transplantation during the study period. Many individual factors contributed moderately to the risk of mortality after the first year. Compared to the general population the mortality rate of renal transplant recipients was significantly higher during the whole follow-up period.  相似文献   
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Sir, We read with interest the recent article by Buzello et al. [1]on renal changes in apo E-/- mice after subtotal nephrectomy.They compared renal lesion development in male wild-type C57BL/6mice with that of genetically modified male apo E-/- mice aftereither sham operation, unilateral nephrectomy or subtotal nephrectomy(SNX) by removal of 75% of the cortex in one kidney and removalof the contralateral kidney. They found  相似文献   
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Brain macrophages synthesize interleukin-1 and interleukin-1 mRNAs in vitro   总被引:10,自引:0,他引:10  
Amoeboid microglial cells (brain macrophages) were purified from early post-natal mouse brain cultures. The percentage of cells stained with an anti-Mac-1 antibody was greater than 95%. Stimulation of these brain macrophages by lipopolysaccharides induced the synthesis of interleukin-1 (IL-1), which, in part, remained associated with the cell surface and, in part, was released into the culture medium. In contrast, pure primary astrocyte cultures and cell lines of transformed or immortalised astrocytes did not synthesise significant amounts of IL-1, demonstrating that amoeboid microglia and not astrocytes synthesise IL-1 in vitro. These physiological data were confirmed by RNA hybridisation studies showing that, on LPS treatment, brain macrophages synthesise significant amounts of IL-1 alpha and IL-1 beta mRNAs.  相似文献   
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We evaluated blood pressure control, quality of life, quality of care, and satisfaction of patients who were monitored by specially trained community pharmacists in a group medical practice. After participating in an intensive skill development program, pharmacists performed in an interdisciplinary team in a rural clinic. The primary objective was assessed by evaluating outcome variables at 6 months compared with baseline in 25 patients randomly assigned to a study group. A control group of 26 patients was also evaluated to determine if outcome variables remained constant from baseline to 6 months. Systolic blood pressure was reduced in the study group (151 mm Hg baseline, 140 mm Hg at 6 mo, p<0.001) and diastolic blood pressure was significantly lower at 2, 4, and 5 months compared with baseline. Ratings from a blinded peer review panel indicated significant improvement in the appropriateness of the blood pressure regimen, going from 8.7 ± 4.7 to 10.9 ± 4.5 in the study group (p<0.01), but they did not change in the control group. Several quality of life scores improved significantly in the study group after 6 months (p<0.05). These included physical functioning (61.6 vs 70.7), physical role limitations (56.8 vs 72.8), and bodily pain (60.0 vs 71.7) at baseline and 6 months, respectively. There were no significant changes in the control group. Patient satisfaction scores were consistently higher in the study group at the end of the study. Our results indicate that when community pharmacists in a clinic setting are trained and included as members of the primary care team, significant improvements in blood pressure control, quality of life, and patient satisfaction can be achieved.  相似文献   
6.
Feeding and drinking rhythms were studied in rats maintained under 24-hr light-dark (LD) cycles with various photoperiods, under two-pulse (2P) and one-pulse (1P) skeleton photoperiods, and under constant dark (DD). Rhythmic waveforms were similar under complete LD cycles and corresponding skeleton photoperiods, indicating that these rhythms mainly reflect the entrainment of underlying circadian pacemakers. Little or no role was found for masking effects of light on circadian feeding and drinking waveforms. Entrainment was found to depend mainly on the timing of the dawn light signal, whether it was a 15-min light pulse or a dark-to-light transition initiating a complete photoperiod. Furthermore, the use of 1P schedules revealed that a dawn signal was sufficient for entrainment. These results closely match those obtained for motor activity measures in other nocturnal rodent species, and generally conform to the predictions of Pittendrigh's nonparametric theory of entrainment. Furthermore, the close correspondence of the two rhythms during entrainment, phase-jumps, and free-running (DD) conditions indicates that they are controlled by common circadian pacemakers.  相似文献   
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Cytotoxic Effect of Brain Macrophages on Developing   总被引:3,自引:0,他引:3  
Brain macrophages are transiently present in different regions of the central nervous system during development or in the course of tissue remodelling following various types of injuries. To investigate the influence of these phagocytes on neuronal growth and survival, brain macrophages stemming from the cerebral cortex of rat embryos were added to neuronal primary cultures. A neurotoxic effect of brain macrophages was demonstrated by the reduction of the number of neurons bearing neurites within two days of contact between the two cell types. Neuronal death and phagocytosis were also directly observed in video recordings of living cultures. This toxicity involved the production by brain macrophages of reactive oxygen intermediates, as shown by the protective effect of catalase, a scavenger of H2O2. In addition, the respiratory bursts of brain macrophages were stimulated in the presence of neurons. These results suggest that brain macrophages could favour the appearance of neuroregressive events which occur either during neurogenesis or in neurodegenerative diseases, implying intracerebral recruitment of mononuclear phagocytes.  相似文献   
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