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81.
AIM: The purpose of this investigation was to examine the extent to which arch dimension or tooth size contributes to dental crowding. METHODS AND MATERIALS: Two groups of dental casts were selected. Each group consisted of 30 pairs of dental casts including equal male and female samples. The first group had Class I malocclusions without crowding or spacing. The second group exhibited Class I malocclusions with severe dental crowding (> a 5 mm space deficiency). The following parameters were measured and used to compare the two groups: individual and collective mesiodistal tooth diameters, dental arch length, as well as buccal and lingual dental arch widths in the canine and molar regions. To compare the two groups the Student's t-test with 95% confidence interval was used. RESULTS: Statistically significant differences in both tooth diameters and transverse arch dimensions were found between the two groups. The crowded group was found to have a significantly smaller maxillary arch width and larger tooth size when compared with the uncrowded group. CONCLUSION: The results of this study suggest under equal conditions (a Class I skeletal relationship) tooth size has a greater role in developing dental crowding.  相似文献   
82.
Due to the known anti-inflammatory and antiviral effects of zinc, 25(OH)D, and vitamin B12, in this study, we explored the association between serum levels of these micronutrients in coronavirus disease 2019 (COVID-19) patients at the time of admission and the clinical outcomes. This study was carried out on 293 patients with COVID-19, who were hospitalized at Imam Hassan hospital (Bojnourd, Iran). We collected demographic data, clinical characteristics, values of serum biochemical parameters in the first week of admission, and clinical outcomes from electronic medical records. We also measured serum levels of zinc, 25(OH)D, and vitamin B12 within 3 days of admission. Of the 293 hospitalized, the median age was 53 years, and 147 (50.17%) were female. Thirty-seven patients (12.62%) were admitted to the intensive care unit (ICU), and forty-two (14.32%) died. We found that the serum levels of zinc, vitamin B12, and 25(OH)D were lower in patients who died than those who were admitted to ICU or non-ICU and survived; however, these differences were not statistically significant for vitamin B12 and 25(OH)D (p > 0.05). The serum concentrations of zinc, vitamin B12, and 25(OH)D at the time of admission did not affect the length of hospital stay in patients with COVID-19. In general, it seems that serum levels of 25(OH)D, vitamin B12, and especially zinc at the time of admission can affect clinical outcomes in COVID-19 patients.  相似文献   
83.
Antibiotic susceptibility testing of 70 pediatric Helicobacter pylori isolates was performed by using screening agar and disk diffusion methods. Resistance to metronidazole and tinidazole was 72 to 79% and 71 to 81% by modified disk diffusion and 77% and 78% by screening agar, respectively. Susceptibilities to amoxicillin, ampicillin, clarithromycin, tetracycline, erythromycin, and ciprofloxacin were 58, 69, 75, 68, 68, and 65%, respectively.  相似文献   
84.
Composite lymphoma (CL) refers to the presence of two or more distinct types of lymphomas in a single organ or tissue. CL is an infrequent finding and may be due to the existence of two genetically related neoplasms, i.e. transformation of a single lymphoma into another lymphoma, or be due to the presence of two clonally unrelated lymphomas. CL composed of more than two lymphomas is even rare. Herein we describe a case of diffuse large B-cell lymphoma (DLBCL) arising in a CL of follicular lymphoma (FL) and small lymphocytic lymphoma (SLL) in an inguinal lymph node of an 85 year old woman. The three lymphomas were morphologically and immunophenotypically distinct while flow cytometry detected two monoclonal B-cell populations. Karyotyping and Polymerase Chain Reaction (PCR) for B-cell clonality each detected a single monoclonal B-cell population. The morphology findings may suggest DLBCL being transformed from FL while Richter transformation from SLL appears to be less likely in our case. Due to the single clone by chromosome study and PCR study, the precise relationships of the three lymphomas are unknown.  相似文献   
85.
Clinical Rheumatology - Dermatomyositis (DM) and polymyositis (PM) are known as two major types of idiopathic inflammatory myopathies (IMMs). During the past years, growing data strongly suggest...  相似文献   
86.
BackgroundIdentifying the predictors of COVID-19 related death in diabetes patients can assist physicians for detecting risk factors related to the worse outcome in these patients. In this study we investigated the predictors of the death in patients with diabetes compared with non-diabetic COVID-19 patients.MethodsIn the present case-control study, the case group were diabetic patients with COVID-19 and the control group included Non-diabetic COVID-19 patients. The data source regarding the demographic characteristics, clinical symptoms, laboratory, and radiological findings on admission as well as the complications, treatment, and outcomes during hospitalization were gathered from their medical record through two trained nurses. Adjusted and unadjusted odds ratios (OR) estimate were calculated using the simple and multiple logistic regression through backward model.ResultsThe mean (SD) age of the case group was higher than that of the control group; [65.24 (12.40) years vs. 59.35 (17.34) years, respectively (P < 0.001)]. Results of the adjusted logistic regression model showed that, advanced age (+60 year) (OR = 5.13, P = 0.006), addiction (OR = 5.26, P = 0.033), high level of Blood urea nitrogen (OR = 5.85, P < 0.001), and high level of Alkaline Phosphatase (OR = 3.38, P = 0.012) in diabetic patients were significantly associated with increase the odds of death in COVID-19 patients.ConclusionWe found that in COVID-19 patients with diabetes; advanced age, addiction, high level of BUN and Alp and in non-diabetic COVID-19 patients advanced age, dyspnea, high level of BUN and SGOT were associated with increase risk of death in these patients.  相似文献   
87.

Introduction

Besides its role in calcium homeostasis, vitamin D (VD) has an important immuno-mudulation effect. However, its role in autoimmune diseases such as type 1 diabetes is under discussion. This study designed to investigate serum VD status in children and adolescents with and without diabetes.

Materials and methods

In a case-control study, 85 diabetic and 85 non-diabetic control (total 170) aged 1–15 yr. were enrolled. History of breast feeding and vitamin supplementation was obtained; growth indices and serum levels of Calcium, phosphorous, Alkaline-Phosphatase (ALP), Hemoglobin-A1c and VD were measured and analyzed.

Results

The mean values for VD in case and control groups were 12.80?±?10.59 and 15.85?±?9.92?nmol/L, respectively (p?=?0.057). Serum VD status in these two groups was sufficient in 5.88% and 9.41%, insufficient in 18% and 14%, and deficient in 75.29% and 76.74%, respectively. Compared to the controls, diabetics had more history of breast-feeding (62.35% vs. 42.35%; p?=?0.017) and higher serum ALP levels (772.34?±?309.89 vs. 657.99?±?395.11?U/L; p?=?0.032).

Conclusion

More frequency of breast-feeding, higher serum ALP and mildly lower serum level of VD in diabetics suggests a significant difference in VD status in diabetics compared to the healthy peers indicating a potential role of this deficiency in the disease process.  相似文献   
88.
Two species of Leishmania (L), L. tropica and L. major, are among the main causative agents of cutaneous leishmaniasis. Arginase (ARG) is an essential enzyme for cell growth, thus an attractive drug target. In this study, we tried to survey the inhibitory impact of ARG by nor-NOHA (N-ω-hydroxy-L-nor-arginine) on in vivo infection caused by L. tropica. BALB/c mice were inoculated with L. tropicaEGFP-LUC (Ltrop) or L. majorEGFP-LUC (Lmj) and then were treated by nor-NOHA. ARG inhibitor only indicated a delay in generation of a cutaneous lesion in inoculated footpad with nor-NOHA-Ltrop and nor-NOHA-Lmj. ARG activity has been significantly reduced in nor-NOHA-Ltrop group. In this group, ARG activity inhibition correlated with increased levels of nitric oxide (NO). In both inoculated mice with Ltrop or Lmj, parasite load showed a significant decrease at later steps during the CL course post-treatment. In vivo bioluminescence intensity did not show any ARG's inhibitory effect on treated-Ltrop. The findings verified that the ARG activity may partially control the L. tropica infection in BALB/c mice through reduction of parasite proliferation and parasite killing through NO generation. This effect is dose-dependent.  相似文献   
89.

Background:

Hypervariability of HCV proteins is an important obstacle to design an efficient vaccine for HCV infection. Multi-epitope vaccines containing conserved epitopes of the virus could be a promising approach for protection against HCV.

Objectives:

Cellular and humoral immune responses against multi-epitope DNA and peptide vaccines were evaluated in BALB/c mice.

Materials and Methods:

In this experimental study, multi-epitope DNA- and peptide-based vaccines for HCV infection harboring immunodominant CD8+ T cell epitopes (HLA-A2 and H2-Dd) from Core (132-142), NS3 (1073-1081) and NS5B (2727-2735), a Th CD4+ epitope from NS3 (1248-1262) and a B-cell epitope from E2 (412-426) were designed. Multi-epitope DNA and peptide vaccines were tested in two regimens as heterologous DNA/peptide (group 1) and homologous peptide/peptide (group 2) prime/boost vaccine in BALB/c mice model. Electroporation was used for delivery of the DNA vaccine. Peptide vaccine was formulated with Montanide ISA 720 (M720) as adjuvant. Cytokine assay and antibody detection were performed to analyze the immune responses.

Results:

Mice immunized with multi-epitope peptide formulated with M720 developed higher HCV-specific levels of total IgG, IgG1 and IgG2a than those immunized with multi-epitope DNA vaccine. IFN-γ levels in group 2 were significantly higher than group 1 (i.e. 3 weeks after the last immunization; 37.61 ± 2.39 vs. 14.43 ± 0.43, P < 0.05). Moreover, group 2 had a higher IFN-γ/IL-4 ratio compared to group 1, suggesting a shift toward Th1 response. In addition, in the present study, induced immune responses were long lasting and stable after 9 weeks of the last immunization.

Conclusions:

Evaluation of multi-epitope DNA and peptide-vaccines confirmed their specific immunogenicity in BALB/c mice. However, lower Th1 immune responses in mice immunized with DNA vaccine suggests further investigations to improve the immunogenicity of the multi-epitope DNA vaccine through immune enhancers.  相似文献   
90.
Behçet’s disease (BD) is a multisystem disease classified among the vasculitides with various clinical features. Genital aphthosis (GA) is one of the major manifestations of BD. The aim of this study was to evaluate the characteristics of BD patients with GA. A cross-sectional sample of BD patients registered in 37 years was selected. We determined clinical and laboratory features of BD patients with GA (GA cases) and compared them with the patients who never developed GA (non-GA cases). The comparisons were performed by the chi-square test and logistic regression analysis. Odds ratios (ORs) with 95 % confidence intervals were calculated to estimate the precision of ORs. Among 6,935 BD patients, 4,489 cases (64.7 %) were ascribed to GA cases. Male to female ratio (1.11:1.00 vs. 1.48:1.00 OR 0.753, P value <0.001) and mean age of disease onset (OR = 0.9, P value <0.001) were lower in GA subset. In GA cases, oral aphthosis (OA) was a more common onset manifestation (OR 2.250, P value <0.001), while uveitis (OR 0.140, P value <0.001) and retinal vasculitis (OR 0.077, P value <0.001) were less common at the disease onset. In the whole course of disease, eye involvement was less common in GA cases (OR 0.215, P value <0.001). On the contrary, OA (OR 19.698, P value <0.001), skin (OR 1.762, P value <0.001), joint (OR 1.257, P value = 0.001), gastrointestinal (OR 1.302, P value = 0.009), neurological (OR 1.624, P value <0.001) and vascular involvements (OR 1.362, P value <0.001), epididymitis (OR 1.596, P value <0.001), positive pathergy test (OR 1.209, P value <0.001) and positive familial history of OA (OR 1.325, P value <0.001) were more common in GA subset. This study showed that GA subset of BD is associated with less eye involvement but higher rates of other BD manifestations.  相似文献   
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