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Betasatellites are a group of circular, single-stranded DNA molecules that are frequently found to be associated with monopartite begomoviruses of the family Geminiviridae. Betasatellites require their helper viruses for replication, movement, and encapsidation and they are often essential for induction of typical disease symptoms. The βC1 protein encoded by betasatellites is multifunctional that participates in diverse cellular events. It interferes with several cellular processes like normal development, chloroplasts, and innate immune system of plants. Recent research has indicated βC1 protein interaction with cellular proteins and its involvement in modulation of the host’s cell cycle and symptom determination. This article focuses on the functional mechanisms of βC1 and its interactions with other viral and host proteins.

  相似文献   
175.

Introduction

Pleomorphic adenoma of minor salivary glands of hard palate is a rare benign tumour. It usually presents as slow growing submucosal mass on hard palate. The purpose of this study was to collect observational data regarding age, size, symptoms, CT findings and treatment of pleomorphic adenoma of hard palate.

Material and methods

The prospective observational study was done in the Department of ENT, Department of Oral and maxillofacial surgery at SKIMS Medical College and at Peoples Care Polyclinic for a period of 2 years. Twenty cases were enrolled in the study. After clinical suspicion, computed tomography, FNAC and core needle biopsy was done in all twenty cases before any surgical intervention was done.

Results

Most common age group seen to be involved was 16–30 years. Most common symptom was submucosal slow growing mass. Core biopsy was diagnostic with 100 % efficacy. On CT scan twelve patients (60 %) were seen to have intact hard palate even without minor erosions while four patients had full thickness erosion of hard palate. Surgical wide excision was done in all cases and one patient needed total maxillectomy. All treated patients were followed for one year and none showed signs of recurrence

Conclusion

Pleomorphic adenoma of hard palate is usually seen in adults. Definitive diagnosis lies on histopathological examination. CT is necessary for ruling out any bony erosion. Treatment is by wide local excision.  相似文献   
176.

Objective:

Pregnancy brings about significant changes in respiratory function, as evidenced by alterations in lung volumes and capacities, which are attributable to the mechanical impediment caused by the growing foetus. This study was undertaken in order to identify changes in respiratory function during normal pregnancy and to determine whether such changes are more pronounced in twin pregnancy than in singleton pregnancy.

Methods:

Respiratory function was assessed in 50 women with twin pregnancies and in 50 women with singleton pregnancies (during the third trimester in both groups), as well as in 50 non-pregnant women. We measured the following pulmonary function test parameters: FVC; FEV1; PEF rate; FEV1/FVC ratio; FEF25-75%; and maximal voluntary ventilation.

Results:

All respiratory parameters except the FEV1/FVC ratio were found to be lower in the pregnant women than in the non-pregnant women. We found no significant differences between women with twin pregnancies and those with singleton pregnancies, in terms of respiratory function.

Conclusions:

Despite its higher physiological demands, twin pregnancy does not appear to impair respiratory function to any greater degree than does singleton pregnancy.  相似文献   
177.

Background/Aims:

In this study, we aimed to determine the prevalence of gastroesophageal reflux disease (GERD) in the general population of the capital city of Riyadh and to assess its association with other factors including age, smoking, body mass index (BMI), asthma, as well as the presence of other co-morbid diseases.

Materials and Methods:

We used the Gastroesophageal Reflux Disease Questionnaire (GerdQ) for diagnosing GERD, based on a GerdQ score of 8 or more. Riyadh was divided into four quadrants, and from each area, a single shopping mall was chosen randomly to conduct our surveys. Data collected included age, sex, history of smoking, history of asthma or any other medical condition, dietary habits, monthly household income, history and frequency of heartburn, epigastric pain, regurgitation of food, nausea, sleep disturbance from heartburn, the use of common over-the-counter antacids for the control of their symptoms, and their height and weight.

Results:

Over a 4-week period from the 19 December 2012 to 17 January 2013, a total of 1265 individuals were included in the survey. The mean age was 29.97 ± 11.58 years. Females formed 67.81% of the respondents and 62.73% had one or more episodes of heartburn per week. Based on a cutoff GERDQ score of 8, the prevalence of GERD in the surveyed population was 45.4%. GERD was more prevalent in older individuals (mean age 31.9 vs. 30.0 years, P < 0.001) and in those with a higher BMI (27.29 vs. 26.31 kg/m2, P = 0.02). There was no difference between males (45.43%) and females (45.13%) (P = 0.92); there was a trend of a higher prevalence in smokers (51.63% vs. 44.41%), but it did not reach statistical significance (P = 0.09).

Conclusion:

Symptoms suggestive of GERD as determined by the translated GerdQ are prevalent among this study population.  相似文献   
178.
Objectives:To establish an association between cigarette smoking, cognition, and plasma brain-derived neurotrophic factor (BDNF) levels in healthy young adults.Methods:This was an ex post facto analytic cross-sectional study conducted between March and November 2018. Participants were 73 healthy males (31 smokers and 42 non-smokers), 17-33 years old. The cognitive function of the participants was assessed through the Cambridge neuropsychological test automated battery (CANTAB). Blood samples were taken to measure the plasma levels of BDNF and the results were compared to identify the association between smoking related variables and cognitive test scores and plasma BDNF levels. A p-value of <0.05 was considered statistically significant.Results:Smokers performed significantly worse than non-smokers in the multitasking test, including reaction time and rapid visual information processing. However, no significant association was observed between smoking related variables and cognitive test scores. The only significant positive correlation was found between plasma BDNF levels and the number of cigarettes smoked per day (r=0.480, p=0.024). No correlation was observed between other smoking related variables and plasma BDNF levels.Conclusion:Plasma BDNF level is positively related to the number of cigarettes smoked per day. Young smokers have significantly impaired sustained attention and less ability to manage conflicting information as compared to age-matched non-smokers.  相似文献   
179.

Background

There is limited data on the natural history of autoimmune hepatitis (AIH) and on the long-term follow-up of AIH patients who have been referred for regular medical attention.

Objectives

We evaluated the clinical presentation and natural history of AIH in a large cohort of type I AIH patients from Iran.

Patients and Methods

Between 1997 and 2008, 102 patients were enrolled in the study. Patients were diagnosed using the International Autoimmune Hepatitis Group criteria and were followed up for an average of 60 months. Clinical and biochemical data were gathered from all the patients at both the beginning and the end of the follow-up period. Liver biopsy was performed in all patients before treatment, and the biopsies were performed in 28 patients after treatment.

Results

Biochemical remission was achieved by 80 (79.4%) patients. Of these, 53 (66.5%) showed near-normal liver histology or liver function test results and sonogram. The remaining 27 (33.5%) patients also achieved clinical and biochemical remission, but developed compensated cirrhosis. After a period of remission, 24 patients (32.5%) relapsed. Among the 22 (21.6%) patients who showed ultimate treatment failure, 6 underwent orthotopic liver transplantation and 3 died of liver failure while awaiting a transplant. Sixteen (72.7%) of the 22 patients who did not respond to therapy were non-compliant with medications and had irregular follow-up. The overall 10-year survival rate in the cohort was 96%.

Conclusions

Long-term survival in AIH patients is very good. Prompt diagnosis and appropriate first-line and salvage therapy that includes close follow-up will make liver transplantation a rare necessity in the treatment of this disease.  相似文献   
180.
BACKGROUND: As patient awareness of new hair transplantation techniques grows, the repair of improperly planned or poorly executed procedures becomes an increasingly important part of surgical hair restoration. OBJECTIVE: Part II of this series is written to serve as a practical guide for surgeons who perform repairs in their daily practices. It focuses on specific repair techniques. METHODS: The repairs are performed by excision with reimplantation and/or by camouflage. Follicular unit transplantation is used for the restorative aspects of the procedure. RESULTS: Using punch or linear excision techniques allows the surgeon to relocate poorly planted grafts to areas that are more appropriate. The key elements of camouflage include creating a deep zone of follicular units, angling grafts in their natural direction, and using forward and side weighting of grafts to increase the appearance of fullness. In special situations, removal of grafts without reimplantation can be accomplished using lasers or electrolysis. CONCLUSION: Meticulous surgical techniques and optimal utilization of a limited hair supply will enable the surgeon to achieve the best possible cosmetic results for patients requiring repairs.  相似文献   
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