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Summary A monoclonal antibody has been produced againstXenopus laevis galactoside-binding neural-creststage lectin. This antibody inhibits lectin-mediated hemagglutination. Using this antibody in conjunction with immunohistochemical techniques, lectin deposition has been studied in embryos and tadpoles at different stages of morphogenesis, from initial neural crest migration, up to the formation of a swimming tadpole. Lectin levels change during development in different regions of the embryo and tadpole, decreasing in migratory cells, and increasing in sites where cells become more adhesive to one another. The results suggest that galactoside-binding lectins may be an important class of cellular adhesion molecules during these stages of development.  相似文献   
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Studies were conducted in selected areas in three states namely Johor (n=117, male=55, female=62), Negeri Sembilan (n=130, male=52, female=78) and Malacca (n=97, male=33, female=64) involving free living elderly (age range from 60 to 93 years old). Respondents were divided into three age cohort groups that is 60 to 69 years, 70 to 79 years and above 80 years old. Assessment of macro and micronutrients were obtained from 24-hour diet recall for three consecutive days. Household measurements were used to estimate the amount of food consumed. Mean energy intake for both sexes were lower than the Malaysian RDA. Mean energy intake were also found to decline with age increment. The percentage of carbohydrate from total calories is higher compared to fat and protein. No respondents were found to consume less than 1/3 RDA for protein. Although no significant difference in nutrient intake was noted among age cohort groups, there was a decline in the intake of protein, fat and carbohydrate. Significantly (p <0.05) lower carbohydrate intake was noted in cohort group above 80 years. As for vitamins and minerals consumption, more than 50% of the elderly population studied consumed less than 2/3 RDA for vitamin A, thiamine, riboflavin, niacin and calcium. Very low intake of nutrient may lead to many health problems. Overall mean energy intake indicate the respondents consume less than the Malaysian RDA for all three age cohort groups. Total mean energy intake were also found to decline with age increment for both sexes. Due to the low energy intake, higher percentage of elderly were found consuming less than 2/3 RDA for thiamine (65%), riboflavin (63%) and niacin (90%). Other nutrients which were also being consumed less than 2/3 RDA by the respondents are vitamin A (67%) and calcium (65%). The intake of calcium which was found to be extremely low (ranged from 277 to 303 mg) could lead to problems like osteoporosis.  相似文献   
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OBJECTIVE: To determine the amount of growth in vestibular schwannomas in Neurofibromatosis type 2 (NF2) patients from diagnosis through short-term (up to 2 yr) and long-term (up to 4 yr) follow-up. STUDY DESIGN: Retrospective magnetic resonance imaging (MRI) films were obtained on subjects enrolled in the NF2 Natural History study and examined for changes in vestibular schwannoma size over time. SETTING: Data were collected from nine foreign and domestic NF2 centers, including hospital-based, academic, and tertiary care centers. SUBJECTS: NF2 patients with MRI data and at least one follow-up examination within 9 months to 2 years of diagnosis were included; n=56 patients with 84 lesions for evaluation of growth. INTERVENTION: Routine, clinically obtained, magnetic resonance images were digitized and measured using image management software. Short-term follow-up was defined as up to 2 years (n=84 lesions), and long-term follow-up was defined as 3 to 4 years (n=29 lesions). OUTCOME MEASURES: Vestibular schwannoma size was assessed using anterior-posterior, medial-lateral, and greatest diameter linear measurements. RESULTS: Vestibular schwannomas increased in size (at least 5 mm) in 8% of the vestibular schwannomas across short-term follow-up. At long-term follow-up, 13% of the tumors had increased in size. On average, schwannomas increased in greatest diameter 1.3 mm per year across short-term follow-up. CONCLUSION: Slightly greater than 1 in 10 diagnosed NF2-related vestibular schwannomas increased in size by at least 5 mm by 4 years of follow-up, if still untreated at that time.  相似文献   
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Background  

Data from patients with colorectal liver metastases (CRLM) who received neoadjuvant chemotherapy before resection were reviewed and evaluated to see whether neoadjuvant chemotherapy influences the predictive outcome of R1 resections (margin is 0 mm) in patients with CRLM.  相似文献   
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There is growing evidence that gut dysbiosis contributes to the progression of chronic kidney disease (CKD) owing to several mechanisms, including microbiota-derived uremic toxins, diet and immune-mediated factors. The aim of this study was to investigate the effect of a ß-glucan prebiotic on kidney function, uremic toxins and the gut microbiome in stage 3 to 5 CKD participants. Fifty-nine participants were randomized to either the ß-glucan prebiotic intervention group (n = 30) or the control group (n = 29). The primary outcomes were to assess kidney function (urea, creatinine and glomerular filtration rate), plasma levels of total and free levels of uremic toxins (p-cresyl sulfate (pCS), indoxyl-sulfate (IxS), p-cresyl glucuronide (pCG) and indoxyl 3-acetic acid (IAA) and gut microbiota using 16S rRNA sequencing at baseline, week 8 and week 14. The intervention group (age 40.6 ± 11.4 y) and the control group (age 41.3 ± 12.0 y) did not differ in age or any other socio-demographic variables at baseline. There were no significant changes in kidney function over 14 weeks. There was a significant reduction in uremic toxin levels at different time points, in free IxS at 8 weeks (p = 0.003) and 14 weeks (p < 0.001), free pCS (p = 0.006) at 14 weeks and total and free pCG (p < 0.001, p < 0.001, respectively) and at 14 weeks. There were no differences in relative abundances of genera between groups. Enterotyping revealed that the population consisted of only two of the four enterotypes: Bacteroides 2 and Prevotella. The redundancy analysis showed a few factors significantly affected the gut microbiome: these included triglyceride levels (p < 0.001), body mass index (p = 0.002), high- density lipoprotein (p < 0.001) and the prebiotic intervention (p = 0.002). The ß-glucan prebiotic significantly altered uremic toxin levels of intestinal origin and favorably affected the gut microbiome.  相似文献   
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OBJECTIVES/HYPOTHESIS: Compare vestibular schwannoma (VS) surgical outcome between patients with prior irradiation and those not previously treated. STUDY DESIGN: Retrospective review with matched control group. METHODS: Review of tumor adherence to the facial nerve, facial nerve grade, and complications in 38 patients with radiotherapy as a primary procedure before VS surgical removal and a matched random sample of 38 patients with primary surgery. The majority of the irradiated group had gamma knife radiation therapy. Mean time from irradiation to surgical salvage was 3.3 years (SD = 3.2), with a minimum of 5.2 months and a maximum of 15.8 years. Most (89.5%) patients in each group underwent a translabyrinthine approach. Mean tumor size at surgery was 2.6 cm in each group. RESULTS: The irradiated group had more moderate to severe adherence of tumor than the controls (89% vs. 63%, P < or = .01). They also had a lower rate of good facial function (House-Brackmann grade I/II) (37% vs. 70%) and a higher rate of poor function (grades V or VI) (50% vs. 18%) at follow-up (P < or = .019). Results were similar when including only those with good preoperative function (50% vs. 72% and 32% vs. 15%) but did not achieve statistical significance. Surgical time and complications did not differ. CONCLUSION: Patients who have undergone irradiation for VS and require surgical salvage may have a more difficult surgery and poorer outcomes than those not previously irradiated. When making their initial choice of treatment, patients should be counseled that surgery might be more difficult after failed stereotactic irradiation.  相似文献   
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Objectives:The purpose of this study was to evaluate antioxidant effect of paraoxonase 1 activity and malondialdehyde (MDA) levels as a marker of oxidative stress in patients suffering from cataract due to diabetes and aging.Design and methods:One hundred cataract patients (senile and diabetic) and age- and sex-matched controls were studied. Paraoxonase 1 and arylesterase activities in plasma samples were measured using paraoxon and phenylacetate as substrates, respectively. The magnitude of lipid peroxidation was established by measuring plasma MDA and oxidized low-density lipoprotein (ox LDL) levels. One-way ANOVA was employed for analysis of results.Results:We observed significantly lower plasma paraoxonase and arylesterase activities in senile and diabetic cataractous patients as compared to respective controls (p < 0.001). Plasma MDA and ox LDL levels were found to be higher in patients suffering from cataract (p < 0.001).Conclusions:The results of present study suggest that the observed decrease in PON1 activity may be due to increase in oxidative stress. It can be concluded that lower paraoxonase activity could contribute to the higher risk of cataract formation.  相似文献   
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