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61.
AIM: To determine pl6 promoter hypermethylation in gastric tumoral tissue and serum samples, its impact on pl6-protein expression, and correlation with clinical and histological features.METHODS: Samples were obtained from 52 histologically confirmed cases of gastric adenocarcinoma. Gastric tissue and serum of 50 age- and sex-matched individuals with normal gastroscopy and biopsy were obtained as control samples. Methylation-specific polymerase chain reaction (MSP) was used to evaluate methylation status of p16 promoter. pl6-protein expression was analyzed by immunohistochemical staining on paraffin-embedded sections.RESULTS: Methylation was detected in 44.2% (23/52) of tumoral tissues. 60.9% of them were also methylated in serum, i.e., 26.9% of all patients (14/52). Methylation was not detected in tissue and sera of control samples. pl6-protein expression was decreased in 61.5% of cases (32/52), and was significantly associated with promoter hypermethylation (P < 0.001). Methylation was significantly more frequent in higher pathological grades (P < 0.05). Methylation was not associated with other clinicopathological features and environmental factors including H pylori infection and smoking.CONCLUSION: pl6 promoter hypermethylation is an important event in gastric carcinogenesis. It is the principle mechanism of pl6 gene silencing. It is related to malignant tumor behavior. Detection of DNA methylation in serum may be a biomarker for early detection of gastric cancer.  相似文献   
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Immunizing infants against measles at the youngest age possible has the potential to reduce morbidity and mortality. The ability of infants at 6, 9, or 12 months to respond to measles and mumps vaccines was evaluated by measuring T cell proliferation, interferon-gamma production, and neutralizing antibody titers before and after vaccination. Infants in all age groups had equivalent cellular immune responses to measles or mumps viruses, with or without passive antibodies when immunized. In contrast, 6-month-old infants without passive antibodies had low geometric mean titers of antibody to measles or mumps viruses and low seroconversion rates. Geometric mean titers of antibody to measles virus increased if infants were revaccinated at 12 months. Six-month-old infants had limited humoral responses to paramyxovirus vaccines, whereas cellular immunity was equivalent to that of older infants. T cell responses can be established by immunization with these live attenuated virus vaccines during the first year, despite the presence of passive antibodies.  相似文献   
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Zarei M, Ghoddusi J, Sharifi E, Forghani M, Afkhami F, Marouzi P. Comparison of the anaesthetic efficacy of and heart rate changes after periodontal ligament or intraosseous X-Tip injection in mandibular molars: a randomized controlled clinical trial. International Endodontic Journal,?45, 921-926, 2012. ABSTRACT: Aim To compare the efficacy of supplemental anaesthesia using periodontal ligament injections (PDL) and intraosseous injections with the X-Tip system in terms of the measured heart rate and patient reported pain level. Methodology In this single-blind randomized clinical trial, 40 patients (22 women, 18 men) with irreversible pulpitis who had experienced unsuccessful pain management by inferior alveolar nerve block with 2% lidocaine and 1?:?100?000 epinephrine were selected. Patients were divided equally and randomly into two groups. Supplementary anaesthesia was provided through intraosseous injection with the X-Tip system (X-Tip group) or by PDL injection (PDL group). After each step of injection, pain severity was assessed using a visual analogue scale. Patient heart rate was recorded with a pulse oximeter. Data were coded and analysed using Mann-Whitney U-test with SPSS (version 16) software. Results Anaesthetic success was obtained in 100% of X-Tip and 70% of PDL group patients after the first supplemental injection. Compared with the first PDL injection, the first intraosseous injection resulted in a significant increase in heart rate (P?=?0.001); however, this increase was short-lived (mean increase: 9-10?beats per min). No significant difference in heart rate or anaesthesia success was observed between men and women. Conclusion Intraosseous injection using the X-Tip system was more effective than PDL injection as a supplementary anaesthetic for pulpectomy in mandibular molars or second premolars. However, the former resulted in a transient increase in heart rate.  相似文献   
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Context  Some studies have inferred that an epidemic of Kaposi sarcoma–associated herpesvirus (KSHV) infection in homosexual men in the United States occurred concurrently with that of human immunodeficiency virus (HIV), but there have been no direct measurements of KSHV prevalence at the beginning of the HIV epidemic. Objectives  To determine the prevalence of KSHV infection in homosexual men in San Francisco, Calif, at the beginning of the HIV epidemic in 1978 and 1979 and to examine changes in prevalence of KSHV at time points from 1978 through 1996 in light of changes in sexual behavior. Design, Setting, and Participants  Analysis of a clinic-based sample (n = 398) derived from the San Francisco City Clinic Cohort (ages 18-66 years) (n = 2666 for analyses herein) and from population-based samples from the San Francisco Men's Health Study (MHS) (ages 25-54 years) (n = 825 and 252) and the San Francisco Young Men's Health Study (YMHS) (ages 18-29 years) (n = 428-976, and 557); behavioral studies were longitudinal and KSHV prevalence studies were cross-sectional. Main Outcome Measures  Antibodies against KSHV and HIV; sexual behaviors. Results  The prevalence of KSHV infection in 1978 and 1979 was 26.5% of 235 (a random sample) overall (weighted for HIV infection) vs 6.9% (128/1842) for HIV in the San Francisco City Clinic Cohort sample. The prevalence of KSHV infection remained essentially unchanged between an MHS sample of 252 in 1984 and 1985 (29.6%) and a YMHS sample of 557 in 1995 and 1996 (26.4%), while HIV prevalence dropped from 49.5% of 825 in 1984 and 1985 (MHS) to 17.6% of 428 in 1992 and 1993 (YMHS). The proportion of men practicing unprotected receptive anal intercourse with 1 or more partners declined from 54% to 11% during the 1984 through 1993 period (MHS) with similar though slightly higher values in the YMHS in 1992 and 1993; whereas for unprotected oral intercourse it ranged between 60% and 90% in the 1984 through 1996 period (MHS and YMHS). Conclusions  Infection with KSHV was already highly prevalent in homosexual men when the HIV epidemic began in San Francisco, and its prevalence has been maintained at a nearly constant level. Any declines in the incidence of Kaposi sarcoma do not appear to be caused by a decline in KSHV transmission.   相似文献   
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We report the first case of blood chimerism involving a pathogenic RB1 variant in naturally conceived monochorionic‐dizygotic twins (MC/DZ) with the twin–twin‐transfusion syndrome (TTTS), presumably caused by the exchange of stem‐cells. Twin A developed bilateral retinoblastoma at 7 months of age. Initial genetic testing identified a de novo RB1 pathogenic variant, with a 20% allelic ratio in both twins' blood. Subsequent genotyping of blood and skin confirmed dizygosity, with the affected twin harboring the RB1 pathogenic variant in skin and blood, and the unaffected twin carrying the variant only in blood.  相似文献   
69.

Background  

Dendritic Cells (DC) are potent antigen presenting cells with the ability to prime na?ve T cells and convert them to cytotoxic T-lymphocytes (CTL). We evaluated the capability of autologous DCs transfected with total tumor and normal RNA to induce cytotoxic CTL as the preliminary step to design a DC-based vaccine in the esophageal squamous cell carcinoma (ESCC).  相似文献   
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The objective of this article was to review the indications for transoral robotic surgery (TORS) in head and neck malignancies. The role of imaging in patient selection will be specifically reviewed. TORS is a recently developed technique that allows minimally invasive surgeries to be performed in the head and neck. TORS has a role in the de‐escalation of oropharyngeal cancers, which allows for lower doses of chemoradiation therapy (this is a technique currently in clinical trials). Additionally, this technique allows for less invasive surgery and decreases associated complications. TORS can also be performed at other subsites. Cross‐sectional imaging has a prominent role to help identify suitable candidates for this type of surgery. This article will review important anatomy and staging related to TORS. Additionally, the key imaging features for patient selection (indications and contraindications) will be presented along with case illustrations.  相似文献   
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