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1.
This study was undertaken to investigate cyclooxygenase-2 (COX-2) expression in follicular cells of the human thyroid. COX-2 expression was studied immunohistochemically in a total of 174 samples. COX-2 immunoreactivity was confined to the cell cytoplasm with the nuclei remaining unlabelled. COX-2 expression was observed in five cases (17.2%) of normal follicular cells and in one case (16.6%) of solid cell nests. Follicular carcinoma expressed COX-2 more frequently than follicular adenoma (93.4% vs 21.1%) (p0.001). A higher percentage of cases of papillary microcarcinomas up-regulated COX-2 in comparison with all papillary carcinomas (p0.05). However, we could not establish any relationships among COX-2, patients ages or lymph node metastases in papillary carcinomas. COX-2 expression was found in 12 (92.3%) poorly differentiated carcinomas and in 13 (92.8%) undifferentiated carcinomas. We found that COX-2 is not always useful as a marker of malignancy. Our results suggest that COX-2 plays a role in progression of all thyroid carcinomas, but in papillary carcinomas, seems more important only in the early stages. COX-2 expression in the undifferentiated carcinoma deserves special consideration due to its prognosis and to the fact that selective COX-2 inhibitors were found to enhance tumour response to radiation in some studies.  相似文献   
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Previously we developed a composite consisting of apatite and wollastonite containing glass-ceramic (AW-GC) powder and bisphenol-a-glycidyldimethacrylate (Bis-GMA)-based resin (designated AWC), and demonstrated that AWC showed direct contact with living bone. Another new composite consisting of mainly the delta-crystal phase of alumina bead powder and Bis-GMA-based resin (designated ABC) was developed. Although alumina ceramics are bioinert and a composite filled with the pure alpha-crystal phase of alumina powder (designated alphaALC) did not allow direct bone formation in vivo, ABC was shown to have excellent osteoconductivity. One purpose of this study was to investigate whether AW-GC powder in a composite promotes osteoblastic differentiation of rat bone marrow cells as AW-GC bulk did. Another purpose was to evaluate the effects of the delta-crystal phase of alumina powder in a composite on osteoblastic differentiation. In a cell culture with dexamethasone, alkaline phosphatase (AP) activity at both days 7 and 14, and the levels of osteocalcin mRNA and alpha1(I) collagen mRNA at day 14 and osteopontin mRNA at day 7, were highest on AWC, followed by ABC, and finally alphaALC. Scanning electron microscopy showed more abundant mineralized globules and a fibrous collagen matrix on AWC at day 14, followed by ABC. In a cell culture without dexamethasone, AP activity at both days 7 and 14, and the level of osteopontin mRNA at day 7, were higher on ABC than on any other composite, whereas osteocalcin mRNA could not be detected. These results indicate that AW-GC powder in a composite promotes osteoblastic differentiation of bone marrow cells intensively when supplemented with dexamethasone. The delta-crystal phase of alumina powder in a composite promotes greater osteoblastic differentiation than the alpha-crystal phase of alumina powder.  相似文献   
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The inner avascular zone of the meniscus has limited healing capacity as the area is poorly vascularized. Although peptide hydrogels have been reported to regenerate bone and cartilage, their effect on meniscus regeneration remains unknown. We tested whether the self‐assembling peptide hydrogel scaffold KI24RGDS stays in the meniscal lesion and facilitates meniscal repair and regeneration in an induced rabbit meniscal defect model. Full‐thickness (2.0 mm diameter) cylindrical defects were introduced into the inner avascular zones of the anterior portions of the medial menisci of rabbit knees (n = 40). Right knee defects were left empty (control group) while the left knee defects were transplanted with peptide hydrogel (KI24RGDS group). Macroscopic meniscus scores were significantly higher in the KI24RGDS group than in the control group at 2, 4, and 8 weeks after surgery. Histological examinations including quantitative and qualitative scores indicated that compared with the control group, the reparative tissue in the meniscus was significantly enhanced in the KI24RGDS group at 2, 4, 8, and 12 weeks after surgery. Immunohistochemical staining showed that the reparative tissue induced by KI24RGDS at 12 weeks postimplantation was positive for Type I and II collagen. KI24RGDS is highly biocompatible and biodegradable, with strong stiffness, and a three dimensional structure mimicking native extracellular matrix and RGDS sequences that enhance cell adhesion and proliferation. This in vivo study demonstrated that KI24RGDS remained in the meniscal lesion and facilitated the repair and regeneration in a rabbit meniscal defect model.  相似文献   
4.
BackgroundHallux valgus (HV) is an important risk factor for falls (in older people); however, the detailed relationship is less understood. We aimed to evaluate postural stability in bilateral HV patients.MethodsTwo groups of 20 female patients—an HV group and a C (i.e., non-HV) group—participated in this study. Evaluations were made using the Timed Up and Go (TUG) test, the Berg Balance Scale (BBS), the Falls Efficacy Scale (FES), track length (LNG), velocity (VEL), enveloped area (ENV), and root mean square area (RMS).ResultsTUG and FES scores were significantly higher and BBS scores were lower in the HV group than in the C group. LNG was significantly longer, VEL was higher, and ENV and RMS were wider in the HV group than in the C group.ConclusionsThe HV group exhibited impaired walking mobility, balance, and postural stability.  相似文献   
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Large vessel occlusion in patients on ECMO is challenging to appreciate clinically secondary to sedation or induced paralysis, thus placing more emphasis on neurovascular imaging. However, emergent CTA and CTP are both inaccurate and unreliable in ECMO patients due to altered circuitry and interference with normal physiologic hemodynamics. In this review, the utility of DSA is discussed in evaluating the altered hemodynamics of VA-ECMO circuits and patency of major vasculature. In addition, the potential use of TCD in ECMO patients is discussed.  相似文献   
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Background

There is limited information about the potential individual-level and contextual drivers of heavy drinking in South Africa. This study aimed to identify risk factors for heavy drinking in Tshwane, South Africa.

Methods

A household survey using a multi-stage stratified cluster random sampling design. Complete consumption and income data were available on 713 adults. Heavy drinking was defined as consuming ≥120?ml (96?g) of absolute alcohol (AA) for men and?≥?90?ml (72?g) AA for women at any location at least monthly.

Results

53% of the sample were heavy drinkers. Bivariate analyses revealed that heavy drinking differed by marital status, primary drinking location, and container size. Using simple logistic regression, only cider consumption was found to lower the odds of heavy drinking. Persons who primarily drank in someone else’s home, nightclubs, and sports clubs had increased odds of heavy drinking. Using multiple logistic regression and adjusting for marital status and primary container size, single persons were found to have substantially higher odds of heavy drinking. Persons who drank their primary beverage from above average-sized containers at their primary location had 7.9 times the odds of heavy drinking as compared to persons who drank from average-sized containers. Some significant associations between heavy drinking and age, race, and income were found for certain beverages.

Conclusion

Rates of heavy drinking were higher than expected giving impetus to various alcohol policy reforms under consideration in South Africa. Better labeling of the alcohol content of different containers is needed together with limiting production, marketing and serving of alcohol in large containers.
  相似文献   
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