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81.
82.
Fibroblast subpopulations in intra-oral wound healing   总被引:3,自引:0,他引:3  
The objective of this study was to characterize fibroblasts at sequential time points during intra-oral wound healing in the rat. Experimental wounds were made at several time points in the mucoperiosteum of the palate of 35-day-old Wistar rats. Fibroblasts were cultured from the biopsies under standard conditions for the same number of passages. The expression of the integrin subunits alpha 1, alpha 6, and beta 1; and the intermediate filaments alpha-smooth muscle actin and vimentin were analyzed by flow cytometry. Western blot analysis was performed at 0, 8, and 60 days postwounding to confirm the expression of both intermediate filaments. The phenotypic profiles of fibroblasts cultured from subsequent stages in the wound healing process differed considerably. We conclude that distinct fibroblast phenotypes can be isolated from different stages in wound healing. These phenotypes remained stable during in vitro culturing. In addition, cryosections of the wound areas were made at identical time points and were immunohistochemically stained for the same antigens. The immunohistochemical staining correlated well to the flow-cytometric data. These results suggest the occurrence of multiple subpopulations of fibroblasts with a specialized function during wound healing. We hypothesize that undesirable consequences of wound healing might be prevented through the modulation of specific fibroblast subpopulations.  相似文献   
83.
We carried out an experimental investigation of cartilage endplate vascularity of degenerated intervertebral discs produced by exogenous melatonin (MEL) treatment. Adult Swiss albino rats were divided into three groups: control, operated degeneration, and MEL treatment. There were five rats in each group and, using a posterior approach, cuts were made parallel to the endplates in the posterior annulus fibrosus in five consecutive intervertebral discs between the 5th and 10th vertebral segments of the rats' tails. At 8 weeks, five of these animals were treated with exogenous MEL (s.c. injection of 30 μg/100 g body weight daily for 4 weeks). In each experimental group, one animal was examined using CT scanner to study the density of the cartilage endplate of the disc. To evaluate the bone growth and vascularity of the cartilage endplate region, the animals were killed for subsequent histopathological evaluation. We found that the vascular channel counts and percentage areas from animals treated with MEL were significantly lower than from the operated degeneration animals. Accordingly, the density histogram in the MEL group showed a spike profile for both the vertebral body and the cartilage endplate, indicating an increase in the amount of higher density tissues in these regions. Our results demonstrate that the use of MEL reduces the cartilage endplate vascularity of degenerated intervertebral discs, suggesting that it may have an osteoinductive effect on bone formation. Further studies are needed to characterize fully the relevance of our findings for the treatment of disorders such as postmenopausal osteoporosis.  相似文献   
84.
85.

Objective

This study evaluates the effect of enteric-coated mycophenolate sodium (EC-MPS) on patient and graft survivals, the incidence of rejection episodes, and graft function among de novo and maintenance renal transplant recipients.

Patients and Methods

This open label, multicenter, prospective, post-marketing observational study of 470 renal transplantation patients at 23 centers in Turkey includes 331 de novo patients whose mean age was 29.6 ± 13.2 years and 139 maintenance patients of 34.0 ± 13.0 years. The latter subjects had EC-MPS substituted for mycophenolate mofetil or added to the immunosuppressive therapy. Patients were followed for 12 months to evaluate graft function and treatment failure.

Results

The most common primary disease requiring transplantation was glomerulonephritis (24.3%). De novo and maintenance groups were similar in terms of overall rejection rates and acute rejection incidence whereas chronic rejection was evident only among the latter cohort (P < 0.001). Time to an acute rejection episode was significantly longer among maintenance rather than de novo patients (220.8 versus 18.7 months; P = 0.015). Overall, 12 and 36 month survival rates were 91.6 ± 1.3% and 86.9% ± 0.3% among subjects experiencing acute rejection versus 99.7 ± 0.2% and 50.3% for those displaying chronic rejection. Among maintenance group no deterioration of renal function was observed after conversion from mycophenolate mofetil to EC-MPS. The incidences of leukopenia, new-onset anemia, or liver dysfunction were similar between de novo and maintenance patients. Gastrointestinal discomfort was more prevalent among the maintenance group, reaching a significant level at the fourth visit (P < 0.05). EC-MPS dose reduction was required in only 16.7% of patients at visit, it was more frequent among the de novo group (17.9 versus 13.8%).

Conclusion

EC-MPS was an effective adjunctive therapy for de novo as well as maintenance renal transplant recipients in the Turkish population due to a relatively low incidence of dose reductions necessitated by adverse events as well as with an increased likelihood of long-term graft survival.  相似文献   
86.
Wound healing in oral mucosa is fast and results in little scar formation as compared with skin. The biological mechanisms underlying this property are poorly understood but may provide valuable information about the factors that promote wound regeneration. Small leucine‐rich proteoglycans (SLRPs) decorin, biglycan, fibromodulin and lumican are extracellular matrix molecules that regulate collagen fibrillogenesis, inhibit transforming growth factor‐β (TGF‐β) activity and reduce scarring. In the present study, we analyzed accumulation of SLRPs and TGF‐β during non‐scarring human oral mucosal wound healing. Biopsies were collected from healthy volunteers from unwounded tissue and from standardized experimental wounds 3–60 days postwounding. Localization of SLRPs, TGF‐β1 and TGF‐β3 was analyzed by immunohistochemical staining and quantitated by image analysis. Double immunostaining was used to study localization of SLRPs or active TGF‐β in distinct cells. Decorin, biglycan, fibromodulin, and TGF‐β isoforms showed significantly increased accumulation in the wound extracellular matrix and distinct wound cells while the abundance of lumican in the extracellular matrix was strongly reduced during wound healing. Localization and abundance of fibromodulin, lumican, and TGF‐β isoforms was also spatiotemporally regulated in the wound epithelium. The findings suggest that SLRPs regulate wound reepithelialization and connective tissue regeneration during oral mucosal wound healing.  相似文献   
87.
Smith Kevin C.  BA  BSc  MD  FACP  FRCPC    Melnychuk Michael  BSc  DDS 《Dermatologic surgery》2005,31(S4):1635-1637
Background. Injection of filler substances into the lips is painful, and many patients also find the injection of local or regional anesthesia into the lips painful.
Objective. To develop a highly effective and painless form of anesthesia to facilitate injection of filler substances into the lips.
Methods. Five percent lidocaine cream was applied simultaneously to the skin, vermilion, and mucosa of the lips (with the use of a barrier to keep the cream in contact with the mucosa and out of the rest of the mouth) for 20 to 30 minutes.
Results. Profound anesthesia of the lips was reliably produced, with no complications.
Conclusions. This "anesthetic cream block" is easier to perform and better tolerated than injectable anesthetics. Use of this technique is likely to expand the range of physicians who perform filler injections on the lips and will probably also expand the range of patients who wish to have filler injections done on their lips and who (because they had little or no discomfort) are willing to return for additional filler injections in the future.  相似文献   
88.
89.
90.

Background

Hyperlipidemia and particularly low-density lipoprotein cholesterol (LDL-C) have been proposed as independent risk factors predisposing to chronic allograft nephropathy.

Objective

The primary objective of this prospective randomized study was to evaluate the efficacy of the modified National Cholesterol Education Program (NCEP) Step I Diet to prevent posttransplantation hyperlipidemia. The secondary objective was to assess the impact of fluvastatin on the lipid profile of patients unresponsive to dietary measures.

Methods

The study population consisted of 143 consecutive patients who underwent transplantation between October 1998 and January 2005. Patients who failed to demonstrate total and LDL-C levels below the optimal values of 200 mg/dL and 130 mg/dL respectively, were recruited for fluvastatin treatment. The remaining patients who achieved and maintained the target lipid levels continued on the same dietary regimen.

Results

Baseline demographic characteristics were not different among the fluvastatin and modified Step I Diet groups. Mean total cholesterol (231.2 vs 187.3 mg/dL; P < .000), LDL-C (134.5 vs 99.2 mg/dL; P < .000), high-density lipoprotein cholesterol (HDL-C; 62.9 vs 55.7 mg/dL; P = .012), and triglyceride (170.3 vs 138.7 mg/dL; P = .011) levels following the dietary run-in period were significantly different between the patients assigned to fluvastatin treatment and those left on the diet, respectively. Fluvastatin achieved reductions ranging from 12% to 14% in the concentrations of total cholesterol (231.2 ± 4.29 mg/dL to 202.7 ± 3.89 mg/dL; P < .000) and LDL-C (134.5 ± 3.53 mg/dL to 115.6 ± 3.18 mg/dL; P < .000) among 91% of patients after 1 year of treatment. A substantial decrease in all lipoprotein concentrations occurred in 53 patients in the modified Step I Diet group with significant reductions in total cholesterol (187.3 ± 4.98 mg/dL to 172.7 ± 3.8 mg/dL; P < .000) and LDL-C (99.2 ± 4.0 mg/dL to 96.2 ± 3.44 mg/dL; P < .000).

Conclusion

Initiation and education of the Step I Diet should be provided during hospitalization. The 3-month dietary run-in period was deemed sufficient to determine the effect of diet on lipid abnormalities. Reduction of lipoprotein levels by a 40-mg daily fluvastatin dose was sufficient, safe, and tolerable.  相似文献   
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