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91.
Repeated exposure to cocaine can induce persistent alterations in the brain's reward system, including increases in the number of dendrites and spine density on medium-sized spiny neurons (MSNs) in the nucleus accumbens (NAc). The structural remodeling of dendrites and spines in the NAc is thought to play a critical role in cocaine addiction. MSNs in the NAc can be classified by expression of either D1 or D2 dopamine receptors, which are localized to the direct and indirect pathway, respectively. It is unknown whether the dendritic changes induced by repeated cocaine treatment occur in MSNs of the direct or indirect pathway. Because the traditional Golgi-Cox impregnation of neurons precludes identifying particular subpopulations of MSNs, we performed dendritic morphology analysis after biocytin-labeling and Golgi-Cox impregnation. We found that the biocytin staining MSNs showed higher dendritic spine density and higher number of dendrites than that in Golgi impregnation group. In addition, we found that the increasing spine density induced by repeated cocaine treatment in female mice was higher than that in male mice. Next we used biocytin staining and dynorphin/D2 receptor colocalization to determine which cell type(s) displayed dendritic changes after repeated cocaine treatment. We found that cocaine-induced changes in dendritic parameters occurred in MSNs of both the direct (D1-expressing) and indirect (D2-expressing) pathways.  相似文献   
92.
The role of laparoscopic resection in the management of colorectal cancer is still unclear. It has been shown that laparoscopic colectomies can be accomplished with acceptable morbidity. Major concerns are port-site recurrences and neoplastic dissemination. The aims of this study were to compare perioperative results and long-term outcomes in a prospective, nonrandomized study of patients treated by laparoscopic versus open colorectal resection for cancer. In particular, the effects of an initial laparoscopic approach on survival and recurrence were examined. One hundred fifty-seven patients with colorectal carcinoma were included in the prospective trial: 74 underwent laparoscopic resection and 83 underwent conventional open surgery. The two groups were comparable in terms of characteristics, demographic data, stage of disease, and use of adjuvant or palliative chemoradiotherapy. All patients were observed at 1.3- and 6-month intervals. The median duration of follow-up was 60 months (range, 10-125 months). The mean operating time was significantly longer in the laparoscopic group. Six conversions (8.1%) were necessary. The passage of flatus and the restarting of oral intake (P = 0.0001) occurred earlier in the laparoscopic surgery group than in the open conventional surgery group. The mean postoperative stay was significantly shorter in the former group (P = 0.005), as was the length of the scar (P = 0.001). There were no deaths in either group. The overall morbidity was significantly lower (13% versus 33.7%; P = 0.001) in patients treated laparoscopically. No significant differences were observed between the groups in the length of specimens, the size of the tumor, or the number of nodes removed. Late complications were more frequent after open resection (12% versus 5.4%; P = 0.01). Two port-site metastases (2.6%) were seen in stage III and IV locally advanced carcinoma. There was no significant difference in recurrent disease between the groups (24.3% versus 25%) during the 60-month follow-up. Stage-for-stage comparisons showed that disease recurrence rates and crude death rates were comparable.  相似文献   
93.
Purpose

Considering the increase in the prevalence of overweight and obese adolescents, this study aimed to analyze the perception of physical competence in Brazilian adolescents of different nutritional status.

Methods

A population-based cross-sectional study was performed and included 2.757 (15?±?4 years-old) adolescent students (1.302 boys, 1.455 girls) from south of Brazil. Strength, flexibility, and aerobic endurance questions were used to evaluate the perception of physical competence. To evaluate nutritional status, body mass index (BMI) was used.

Results

The prevalence of overweight and obesity in adolescents was 21.2%, with 25.4% for boys and 17.5% for girls. Girls with lower perception of aerobic endurance were more likely to be overweight/obese. Boys with a poor perception of flexibility were about 10 times more likely to be overweight/obese. Adolescents with a weak and moderate perception of strength were less likely to be overweight/obese.

Conclusion

We concluded that perception of physical competence differs depending on the nutritional status of adolescents. Lower perceptions of aerobic endurance and flexibility favor the development of overweight and obese adolescents. However, greater perception of strength competence mostly appears in overweight/obese adolescents.

  相似文献   
94.
To describe the intra-ocular manifestations of cat-scratch disease (CSD) found at two uveitis reference centers in Brazil. Retrospective case series study. Review of clinical records of patients diagnosed with CSD in the Uveitis Department of São Geraldo Hospital and the Ophthalmology Department of the Instituto de Pesquisa Clínica Evandro Chagas—FIOCRUZ, from 2001 to 2008. In the 8-year period, 24 patients with the diagnosis of CSD were identified. Twelve patients were male and 12 female. The mean age was 27.04 years (range 7–56). Sixteen patients (66.6%) presented with a history of a cat scratch and all patients reported cat exposure. Visual acuity ranged from counting fingers to 1.0 in the affected eye. Thirteen patients presented with bilateral disease. Sixteen (66.6%) patients complained of systemic symptoms, including fever, lymphadenopathy, liver and spleen enlargement and rash. All patients presented with serum antibodies (IgG) to Bartonella henselae. Thirty-seven eyes were affected. The most common findings were small areas of retinal infiltrates which occurred in 11 eyes (29.7%) and angiomatous lesions which occurred in nine eyes (24.3%). Neuroretinitis occurred in only six eyes (16.2%). The most common findings of CSD in our study were retinal infiltrates and angiomatous lesions. CSD patients may present with significant visual loss. Patients may benefit from systemic treatment with antibiotics.  相似文献   
95.
Bartonellosis is an emerging serious diseases of zoonotic relevance caused by an expanding number of recently discovered species of Bartonella. Many studies use partial gltA gene sequencing as the method of choice for species attribution, and a plethora of studies have utilized only this gene to describe Bartonella diversity. We observe a lack of correspondence between the phylogenies constructed using the complete gltA gene sequences and the small gene fragment usually used in phylogenetic analyzes. Everything indicates that important changes occurred by using larger fragments. Therefore, it is of great importance to define a minimum gltA fragment length to be used in future phylogenetic analyzes, besides the use of other genes.  相似文献   
96.
The transition period is marked by intense metabolic changes that defy calcium homeostasis, and compromise the immune capacity of dairy cows, what denotes interaction between metabolic status and immune activity. The adenosine deaminase (ADA) regulates adenosine levels; a molecule with anti-inflammatory properties that can act in reducing the production of pro-inflammatory cytokines and reactive oxygen species (ROS), which in exacerbated production is harmful to health. Therefore, the aim of this study was to evaluate the relationship between seric levels of calcium levels and ADA in prepartum and postpartum of dairy cows. To evaluate these variables, Holstein cows were subjected to blood collection in the transition period (days 20, 10, and 5 prepartum; and days 3, 7, 12, and 20 postpartum) and where we evaluated the serum levels of calcium and the ADA activity. An increase in the ADA activity was observed mean day 20 to day 10 postpartum (P < 0.001). Numerically, in other periods evaluated, ADA activity was higher when compared to day 20 prepartum. The serum calcium significantly reduced from 5 days prepartum, keeping smaller the day 20 prepartum until day 12 postpartum (P < 0.02). There was a negative correlation between serum calcium levels and ADA activity. The increase of ADA can be related to modulation of the inflammatory response that occurs during the transition period for cows.  相似文献   
97.
Fungi of the genus Fusarium are well known as major plant pathogens and soil inhabitants, but also cause a broad spectrum of human infections. Fusariosis is the second most common mould infection after aspergillosis, and keratitis is the most encountered implantation infection in immunocompetent individuals. Natamycin is active against Fusarium species both in vitro and in vivo, and is used along with voriconazole as the mainstay of treatment for Fusarium keratitis. Onychomycosis is treated with terbinafine, voriconazole and sometimes itraconazole. Cure is possible despite high in vitro minimum inhibitory concentrations (MICs). Recently, disseminated infections have increased dramatically, mainly affecting severely immunocompromised patients. The remarkable intrinsic resistance of Fusarium species to most antifungal agents results in high mortality rates in this patient population. Recovery of neutropenia is essential for patient survival and treatment should include voriconazole or amphotericin B as first–line and posaconazole as salvage therapy.  相似文献   
98.
Ninety-one Helicobacter pylori-positive patients with nonulcer dyspepsia were randomized to receive either lansoprazole, amoxicillin, and clarithromycin or lansoprazole and placebo. A validated questionnaire assessed dyspeptic symptoms at baseline and at 3, 6, and 12 months. Endoscopies and biopsies were performed at baseline and at 3 and 12 months. There was an overall trend, although not statistically significant, for a benefit of H. pylori eradication. Of the patients in the antibiotics group, 16 of 46 (35%) had symptomatic improvement, versus 9 of 43 (21%) in the control group (P = 0.164). In a secondary analysis, it was found that of the patients without endoscopic gastric erosions, 15 of 34 (44%) in the antibiotics group and 5 of 33 (15%) of controls had symptomatic improvement (P = 0.015). Helicobacter pylori eradication did not prove to be clinically beneficial, although a tendency to symptomatic benefit was detected. Further studies are necessary to confirm the implications of endoscopic gastric erosions in these patients. Abbott Laboratórios do Brasil Ltda. donated the drugs used in this clinical trial. The Research Incentive Fund (FIPE) and the Graduate Research Group at Hospital de Clínicas de Porto Alegre provided editorial support. No member of the research team received any remuneration to conduct this study.  相似文献   
99.
An open-design, prospective, non-comparative study was conducted to evaluate the efficacy and safety of itraconazole in the treatment of tinea pedis (interdigital-type, hyperkeratotic-type and the combination of both). Treatment consisted of one pulse of itraconazole, meaning that each patient received 400 mg/day for one week. Clinical and mycologic control examinations were performed at baseline and at the end of treatment; follow-up visits took place at 30 and 60 days after the last medication administration. A total of 44 patients were evaluated. The major causal agent isolated was Trichophyton rubrum (93%). At the final follow-up visit (60 days), 37 cases (84.4%) achieved clinical and mycologic cure; 5 (11.3%) had improvement and 2 cases (4.5%) failed. Three cases reported side effects attributable to itraconazole (6.6%); one patient had a moderate headache and two reported moderate dyspepsia. None of the 3 cases required discontinuation of the medication. We concluded that the administration of one pulse of itraconazole is an effective, safe and short regimen to treat tinea pedis.  相似文献   
100.
Lactate and glucose metabolism in severe sepsis and cardiogenic shock   总被引:6,自引:0,他引:6  
OBJECTIVE: To evaluate the relative importance of increased lactate production as opposed to decreased utilization in hyperlactatemic patients, as well as their relation to glucose metabolism. DESIGN: Prospective observational study. SETTING: Surgical intensive care unit of a university hospital. PATIENTS: Seven patients with severe sepsis or septic shock, seven patients with cardiogenic shock, and seven healthy volunteers. INTERVENTIONS: C-labeled sodium lactate was infused at 10 micromol/kg/min and then at 20 micromol/kg/min over 120 mins each. H-labeled glucose was infused throughout. MEASUREMENTS AND MAIN RESULTS: Baseline arterial lactate was higher in septic (3.2 +/- 2.6) and cardiogenic shock patients (2.8 +/- 0.4) than in healthy volunteers (0.9 +/- 0.20 mmol/L, p < .05). Lactate clearance, computed using pharmacokinetic calculations, was similar in septic, cardiogenic shock, and controls, respectively: 10.8 +/- 5.4, 9.6 +/- 2.1, and 12.0 +/- 2.6 mL/kg/min. Endogenous lactate production was determined as the initial lactate concentration multiplied by lactate clearance. It was markedly enhanced in the patients (septic 26.2 +/- 10.5; cardiogenic shock 26.6 +/- 5.1) compared with controls (11.2 +/- 2.7 micromol/kg/min, p < .01). C-lactate oxidation (septic 54 +/- 25; cardiogenic shock 43 +/- 16; controls 65 +/- 15% of a lactate load of 10 micromol/kg/min) and transformation of C-lactate into C-glucose were not different (respectively, 15 +/- 15, 9 +/- 18, and 10 +/- 7%). Endogenous glucose production was markedly increased in the patients (septic 14.8 +/- 1.8; cardiogenic shock 15.0 +/- 1.5) compared with controls (7.2 +/- 1.1 micromol/kg/min, p < .01) and was not influenced by lactate infusion. CONCLUSIONS: In patients suffering from septic or cardiogenic shock, hyperlactatemia was mainly related to increased production, whereas lactate clearance was similar to healthy subjects. Increased lactate production was concomitant to hyperglycemia and increased glucose turnover, suggesting that the latter substantially influences lactate metabolism during critical illness.  相似文献   
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