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101.
102.
目的: 探讨正畸应力变化下牙龈组织α平滑肌肌动蛋白(α-SMA)、Ⅰ型及Ⅲ型胶原变化以及龈沟液基质金属蛋白酶2(MMP-2)、金属蛋白酶组织抑制因子2(TIMP-2)的表达。方法: 选取南昌大学附属口腔医院2018年4月—2019年4月收治的正畸患者74例,随机分为A组(24例,0 g力)、B组(25例,75 g力)、C组(25例,150 g力)3组。于加力0、4周采集患者部分牙龈组织,采用免疫组织化学染色法检测α-SMA、Ⅰ型及Ⅲ型胶原表达水平。在加力后0、2、4周收集龈沟液,采用酶联免疫吸附法检测MMP-2、TIMP-2表达水平。采用Spearman相关性分析不同正畸应力与α-SMA、Ⅰ型胶原、Ⅲ型胶原、MMP-2、TIMP-2表达水平的相关性。采用SPSS 19.0软件包对数据进行统计分析。结果: 加力2周及加力4周,3组患者龈沟液MMP-2、TIMP-2表达水平依次升高(P<0.05);加力4周后,3组患者牙龈组织中α-SMA、Ⅰ型及Ⅲ型胶原水平依次升高(P<0.05);不同正畸应力与MMP-2、TIMP-2、α-SMA、Ⅰ型胶原及Ⅲ型胶原表达水平均呈正相关(P<0.05)。结论: 龈沟液TIMP-2、MMP-2表达水平以及肌成纤维细胞表达与正畸应力变化有关,可能在正畸治疗的牙周组织改建中发挥重要作用。  相似文献   
103.
BackgroundThere is a tendency nowadays to encourage the use of natural substances in dentistry. Aloe vera is one of these substances, which has recently gained great importance in clinical research.ObjectivesTo evaluate the effectiveness of Aloe vera mouthwash in improving plaque, gingival and gingival bleeding indices in children.Materials and methodsThe study sample consisted of (17) children [age: (8) to (12) years]. The crossover design was applied, which means that the three types of mouthwashes (experimental “Aloe vera”, positive control “chlorhexidine”, and negative control “placebo”) would be used for all participants, with a washout period of (12) days. A special plaque guard was fabricated to facilitate localized plaque accumulation for (3) days. After that period, the mouthwashes were applied for (5) days. Plaque, gingival and gingival bleeding indices were studied before plaque accumulation (T0), after plaque accumulation (T1), and after applying the mouthwashes (T2). The values of plaque index (PI), gingival index (GI) and gingival bleeding index (GBI) were measured at each studied time point (T0, T1, and T2). Then, the differences between the values at the beginning of the use of each type of the mouthwashes and at the end of the period of there use were compared.ResultsThe results showed the efficacy of Aloe vera mouthwash in improving plaque, gingival and gingival bleeding indices, which was similar to chlorhexidine mouthwash effectiveness when both compared to the placebo mouthwash.ConclusionsThe use of Aloe vera mouthwash is effective in improving oral health and preventing gingivitis.  相似文献   
104.
OBJECTIVES: Angiotensin II suppression leads to impaired vascular relaxation in normotensive animals on a high-salt diet. The goal of this study was to determine whether normal vascular reactivity could be restored by transferring the chromosomal region carrying the Dahl salt-resistant (R) renin gene into the Dahl salt-sensitive (SS) genetic background in a strain of renin congenic rats (RGRR). METHODS: Male RGRR and SS rats were fed low-salt (0.4%) and high-salt (4%) diets for 4 weeks. The responses of cremaster muscle arterioles to acetylcholine (ACh), sodium nitroprusside (SNP), and elevated PO2 were assessed using video microscopy. RESULTS: ACh-induced dilation was significantly enhanced in RGRR on a high-salt diet compared to SS rats, while dilation to the NO donor SNP was similar in both strains. A high-salt diet significantly enhanced arteriolar constriction in response to elevated PO2, in both SS and RGRR rats. CONCLUSIONS: These data suggest that transfer of the chromosomal region containing the renin gene is crucial in the recovery of ACh-induced dilation of arterioles in RGRR rats vs. SS rats, and that factors in the SS genetic background contribute to an enhanced sensitivity to elevated PO2, independent of genes on chromosome 13.  相似文献   
105.
Diabetic vascular lesions and peripheral autonomic neuropathy are both closely linked to long-term metabolic control of diabetes. Transcutaneous oxygen tension (P tcO2) measurements were made to elucidate whether autonomic neuropathy disturbs the cutaneous microciculatory blood flow, and whether long-term glucose normalization ameliorates such impairment. Twenty-eight type 1 (insulin-dependent) diabetic patients in whom clinically significant macroangiopathy had been excluded by angiography were studied, subdivided into group An=14; before simultaneous pancreas/kidney transplantation (SPKT); mean age 35 years, range 22–51 years; mean duration of diabetes 24 years, (range 15–32) years and group B (n=14; mean 31 months, range 2–101 months, after successful SPKT; mean age 35 years, range 19–56 years; mean duration of diabetes 22 years, range 14–29 years). On addition there was a group (group C) of age-and sex-matched healthy control subjects (n=14; mean age 35 years, range 23–62 years).P tcO2 measurements included basal recordings at 44°C on the leg and the foot, functional recordings at 44°C after arterial occlusion of the limb for 4 min, measurements during breathing 5 l oxygen per minute and finally while standing up (stand up dP 50/dt). All subjects underwent extensive cardiac autonomic testing. In this cross-sectional study the recordings of basal values and of the functional parameters after arterial occlusion and during breathing oxygen did not differ significantly between groups A, B and C. The stand-up dP 50/dt values were not significantly different between groups A and B (0.43±0.02 vs 0.47±0.03 mmHg/s, mean ± SEM); but A+B values were significantly higher than in C (0.22±0.01 mmHg/s;P<0.001). These values were correlated significantly with all parameters of cardiac autonomic neuropathy (r range–0.56 to –0.88;P<0.001). It may be concluded that normalization of blood glucose by pancreatic transplantation is not able to ameliorate peripheral microcirculation, but that measurement of transcutaneous oxygen tension is a possible new technique for quantifying alterations in the venoarteriolar reflex in peripheral diabetic autonomic neuropathy that lead to disturbed peripheral microcirculation in diabetic patients.  相似文献   
106.
Burkitt's lymphoma(BL) is an aggressive form of nonHodgkin's B-cell lymphoma with three variants namely endemic, sporadic, and immunodeficiency-associated types. It is endemic in Africa and sporadic in other parts of the world. While the endemic form is widely reported to occur in early childhood and commonly involves the jaw bones, the sporadic form typically presents as an abdominal mass. This presentation reports a rare case of sporadic form of BL clinically manifesting as a generalized gingival enlargement in an immunocompetent adult male which demonstrated an aggressive behavior. The patient reported with a prominent anterior gingival swelling of 6 mo duration which slowly enlarged in size and associated with multiple lymph node involvement. Microscopic examination of the lesion using H, E and immunohistochemical diagnosis confirmed the diagnosis as BL. The patient succumbed to the disease before any therapy could be instituted. Since a wide array of causes can be attributed to gingival enlargements, it is necessary to consider malignancies as one of the important differential diagnosis so as to facilitate the need for appropriate diagnosis and prompt treatment.  相似文献   
107.
Background: To investigate changes in the levels and relative ratios of sclerostin, osteoprotegerin (OPG), and receptor activator of nuclear factor‐κB ligand (RANKL) in the gingival crevicular fluid (GCF) of patients with periodontitis after non‐surgical periodontal treatment. Methods: Fifty‐four individuals (27 healthy controls and 27 patients with chronic periodontitis [CP]) were enrolled in the study. Periodontitis patients received non‐surgical periodontal therapy. GCF sampling and clinical periodontal parameters were assessed before and 6 weeks after therapy. Sclerostin, OPG, and RANKL levels were measured by enzyme‐linked immunosorbent assay, and their relative ratios were calculated. Results: Total amounts and concentrations of sclerostin were significantly higher in patients with CP than in healthy individuals (P <0.025) and decreased after treatment (P <0.05). The RANKL/OPG ratio was significantly lower in healthy individuals than in patients with periodontitis before and after treatment (P <0.025), but no significant difference was observed in patients with periodontitis after treatment (P >0.05). The sclerostin/OPG and sclerostin/RANKL ratios were significantly lower in healthy individuals than in patients with periodontitis before and after treatment (P <0.025) and decreased in patients with periodontitis after treatment (P <0.05). Conclusions: The GCF sclerostin level may be more reliable than the RANKL/OPG ratio as a diagnostic and prognostic marker of periodontal disease and treatment outcome. Regulation of sclerostin levels may aid the development of new therapeutic strategies for the treatment of periodontal disease.  相似文献   
108.
Background: A novel member of the interleukin (IL)‐12 family, IL‐35 is an important inhibitory cytokine released by regulatory T cells. The aim of this study is to evaluate gingival crevicular fluid (GCF), saliva, and plasma levels of IL‐35 in periodontal disease and health. Methods: Samples of GCF, whole saliva, and plasma were obtained from systemically healthy, non‐smoking individuals with gingivitis (n = 20) or chronic periodontitis (CP) (n = 20) and periodontally healthy individuals (n = 20). Full‐mouth clinical periodontal measurements, including probing depth (PD), bleeding on probing, gingival index, and plaque index (PI), were also recorded. Enzyme‐linked immunosorbent assay was used to determine IL‐35 levels in the samples. Data were tested statistically by analysis of variance and Pearson rank correlation test. Results: All clinical parameters were significantly higher in the CP group than the healthy and gingivitis groups (P <0.001). The GCF total amount of IL‐35 was significantly higher in the CP group than the other groups (P = 0.04), whereas the GCF concentration of IL‐35 was significantly higher in the healthy group than the other groups (P = 0.002). There were significant differences among the study groups in terms of salivary IL‐35 level (P <0.001), with the highest level observed in the healthy group and the lowest in the CP group. There was no statistical difference between groups in plasma levels of IL‐35 (P >0.05). There was a positive correlation between GCF total amount of IL‐35 and PD (r = 0.338, P = 0.03) and PI (r = 0.374, P = 0.005) parameters. Conclusions: IL‐35 could have an important role in suppressing periodontal inflammation and maintaining periodontal health. Additional studies are required to evaluate its role in periodontal diseases.  相似文献   
109.
目的:评估上前牙区即刻种植联合即刻修复的软组织效果。方法上前牙区单牙即刻种植患者26例,微创拔牙后植入ZIMMER TSV种植体,获得良好初期稳定性并实施即刻修复,经过6~12个月骨结合和牙龈塑形后完成上部修复,观察负重6个月后牙龈组织情况。结果26例患者完成骨整合及最终修复,负重正常,无探诊出血、牙龈红肿,近中龈乳头、远中龈乳头及龈缘高度降低分别为(0.52±0.22) mm、(0.56±0.31) mm 和(0.71±0.34) mm,差异无统计学意义(F=1.297,P=0.29)。结论上前牙区单牙即刻种植联合即刻修复存在不同程度的软组织退缩。  相似文献   
110.

Background

Esthetics represents an inseparable part of today''s oral therapy, and several procedures have been proposed to preserve or enhance it. Gingival recessions may cause hypersensitivity, impaired esthetics and root caries. Keeping in mind patient''s desire for improved esthetics and other related problems, every effort should be made to achieve complete root coverage.

Methods

Different types of modalities have been introduced to treat gingival recession including displaced flaps, free gingival graft, connective tissue graft, different type of barrier membranes and combination of different techniques. The aim of this study was to compare the commonly used techniques for gingival recession coverage and evaluate the results obtained. 73 subjects were selected for the present study who were randomly divided into four groups and were followed at baseline and 180 days where following parameters were recorded: (a) Assessment of gingival recession depth (RD); (b) Assessment of pocket depth (PD); (c) Assessment of clinical attachment level (CAL) and (d) Assessment of width of attached gingiva (WAG).

Results

Results of this study showed statistically significant reduction of gingival recession, with concomitant attachment gain, following treatment with all tested surgical techniques. However, SCTG with CAF technique showed the highest percentage gain in coverage of recession depth as well as gain in keratinized gingiva. Similar results were obtained with CAF alone. The use of GTR and other techniques showed less predictable coverage and gain in keratinized gingiva.

Conclusion

Connective tissue grafts were statistically significantly superior to guided tissue regeneration for improvement in gingival recession reduction.  相似文献   
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