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1.
Fate of micelles and quantum dots in cells.   总被引:2,自引:0,他引:2  
Micelles and quantum dots have been used as experimental drug delivery systems and imaging tools both in vitro and in vivo. Investigations of their fate at the subcellular level require different surface-core modifications. Among the most common modifications are those with fluorescent probes, dense-core metals or radionucleids. Cellular fate of several fluorescent probes incorporated into poly(caprolactone)-b-copolymer micelles (PCL-b-PEO) was followed by confocal microscopy, and colloidal gold incorporated in poly 4-vinyl pyridine-PEO micelles were developed to explore micelle fate by electron microscopy. More recently, we have examined quantum dots (QDs) as the next-generation-labels for cells and nanoparticulate drug carriers amenable both to confocal and electron microscopic analyses. Effects of QDs at the cellular and subcellular levels and their integrity were studied. Results from different studies suggest that size, charge and surface manipulations of QDs may play a role in their subcellular distribution. Examples of pharmacological agents incorporated into block copolymer micelles, administered or attached to QD surfaces show how the final biological outcome (e.g. cell death, proliferation or differentiation) depends on physical properties of these nanoparticles.  相似文献   
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A case of an unusual lesion from the maxilla is presented. Macroscopically, the lesion was solid and histologically consisted of 'multiple separate keratocysts' of varying size that infiltrated into the surrounding bone and soft tissues. Panoramic image and CT scans showed a multilocular honeycomb ill-defined radiolucency with infiltration into the maxillary sinus and floor of orbit. This lesion should be differentiated from similar odontogenic lesions, such as keratoameloblastoma and papilliferous keratoameloblastoma. As there was no evidence of follicles, islands of ameloblastoma, or papilliferous structures in the entire specimen, the lesion could not be diagnosed as either a keratoameloblastoma or a papilliferous keratoameloblastoma. The invasive and destructive growth behavior, the histopathological features, and the histochemical pattern of the collagen stroma imply that this solid lesion is a neoplasia. It is suggested that the proper term for this lesion is solid variant of odontogenic keratocyst.  相似文献   
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Objectives:To determine the prevalence of depression and anxiety in adult multiple sclerosis patients attending tertiary facilities in Riyadh, Saudi Arabia.Methods:This is a cross-sectional study conducted among MS patients in Riyadh City, Saudi Arabia. A self-administered questionnaire was distributed among MS patients at Prince Sultan Military Medical City in Riyadh, Saudi Arabia between April 2020 and January 2021. The questionnaire consisted of socio-demographic characteristics and the Hospital Anxiety and Depression Scale (HADS). Univariate using Chi-square test and multivariate regression analysis had been performed to determine the factors associated with anxiety and depression among MS patients.Results:A total of 328 MS patients took part in the study. The most prevalent age group was 36–45 years old (38.4%), with over 70% of the participants being females. Anxiety and depression were shown to be prevalent in MS patients at 42.9 percent and 58.8 percent, respectively. According to statistical tests, being less educated and having partial to severe disability was linked to an increased rate of anxiety and depression, whereas being female was more prone to anxiety symptoms but not depression.Conclusion:Depression was more frequent than anxiety. As a result, while assessing psychiatric diseases in the study group, depression/anxiety may be expected to be more frequent amongst those of greater disability.

Multiple sclerosis (MS) is a central nervous system demyelinating disease caused by an immunological response. Depression and anxiety are more common in patients with multiple sclerosis (PWMS) than in the general population, 1-4 which is a well-known phenomenon. However, we believe that these illnesses are under-recognized in PWMS because several MS symptoms overlap with depression and anxiety, making detection more difficult. Fatigue, sleeplessness, anorexia, memory loss, and concentration problems are all common symptoms of depression, MS, or both. 5,6 Furthermore, the symptoms of MS might mislead self-report rating scales designed to detect depression and anxiety, resulting in false positives or negatives. 5,6 Moreover, depression in PWMS can impair their quality of life (QOL), medication adherence, and compliance, worsening their prognosis. 7-9 Suicidal thoughts and attempts are also common. 10-13 The hospital Anxiety and Depression Scale is a one-of-a-kind measure for detecting anxiety and depression while taking into account both disorders’ possible confounders, and it has been validated for use in PWMS. 6 Depression is a significant mood illness that affects many people. It creates severe symptoms that impact how you feel, think, and handle day-to-day tasks like working, sleeping, and eating. 14 In PWMS, the lifetime prevalence of depression in up to 50%, 3 compared to 10.8% in the general population. 15 The cause of depressive disorders in people with MS is unknown. However, it is assumed to be complex, with psychological, social, and neurological aspects - as well as immunologic and genetic factors - all having a part. 16 Furthermore, depression can have a severe impact on these patients’ health by raising the severity of their symptoms and reducing their compliance with therapy and follow-up, both of which have an impact on their medical costs. 9 In addition to a decreased quality of life (QOL), cognitive impairment, and an increased risk of suicide, especially when anxiety is present. 7,10,11 Furthermore, PWMS have a 10-year lower life expectancy than the general population of the same age. 2 Patients, caregivers, and care providers should not underestimate the impact of sadness and anxiety on PWMS. Improved identification, diagnosis, and treatment in medical offices, where people with mood disorders are frequently seen for the first time, can assist to improve these negative outcomes. 17 Unfortunately, despite convincing evidence of its high incidence, greater influence on prognosis, and quality of life, depression and anxiety are still underdiagnosed and undertreated. 13 The goal of this study is to find out how common depression and anxiety are among adult patients with multiple sclerosis in Riyadh, Saudi Arabia. We’ll also see if there’s a link between Hospital Anxiety and Depression Scale (HADS) score and patients’ demographical, socio-educational, and MS-related characteristics, as well as MS duration, Immunomodulatory type, and EDSS scores.  相似文献   
6.

Objective

To characterize organisms causing wound infection following abdominal hysterectomy.

Study design

All patients who underwent an abdominal hysterectomy (December 2002–January 2006) and developed abdominal wall wound infection proven by a positive culture were included in the study. Patient information was collected from the computerized files. The isolated microorganisms were characterized for antibiotics susceptibility.

Results

Sixty-eight (68/620, 10.96%) patients had positive wound cultures. Of 100 isolated microorganisms, 44 were resistant to cefonicid (prophylactic treatment) and 15 were resistant to combined ampicillin, gentamicin and metronidazole (empirical treatment). Major co-morbidities (including diabetes mellitus, hypertension, past malignancies, renal, cardiovascular and pulmonary diseases, hypothyroidism or anemia), were found to be significantly associated with pseudomonal infection (P < .008).

Conclusion

A significant portion of pathogens causing post-hysterectomy abdominal wall wound infection are resistant to the prophylactic treatment, and some are resistant to the empirical treatment. Further studies are necessary to evaluate the effectiveness of various prophylactic regimens with better coverage of Enterococcus fecalis, as well as the effectiveness of empirical treatment active against the resistant Enterobacteriaceae group.  相似文献   
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Attachment theory is built on the assumption of consistency; the mother–infant bond is thought to underpin the life-long representations individuals construct of attachment relationships. Still, consistency in the individual’s neural response to attachment-related stimuli representing his or her entire relational history has not been investigated. Mothers and children were followed across two decades and videotaped in infancy (3–6 months), childhood (9–12 years) and young adulthood (18–24 years). In adulthood, participants underwent functional magnetic resonance imaging while exposed to videos of own mother–child interactions (Self) vs unfamiliar interactions (Other). Self-stimuli elicited greater activations across preregistered nodes of the human attachment network, including thalamus-to-brainstem, amygdala, hippocampus, anterior cingulate cortex (ACC), insula and temporal cortex. Critically, self-stimuli were age-invariant in most regions of interest despite large variability in social behavior, and Bayesian analysis showed strong evidence for lack of age-related differences. Psycho–physiological interaction analysis indicated that self-stimuli elicited tighter connectivity between ACC and anterior insula, consolidating an interface associating information from exteroceptive and interceptive sources to sustain attachment representations. Child social engagement behavior was individually stable from infancy to adulthood and linked with greater ACC and insula response to self-stimuli. Findings demonstrate overlap in circuits sustaining parental and child attachment and accord with perspectives on the continuity of attachment across human development.  相似文献   
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Objective

The prevalence of skull fractures after mild head trauma is 2 % in children of all ages and 11 % in children younger than 2 years. The current standard management for a child diagnosed with an isolated skull fracture (ISF), in our institute, is hospitalization for a 24-h observation period. Based on data from the literature, less than 1 % of all minor head injuries require neurosurgical intervention. The main objective of this study was to evaluate the risk of neurological deterioration of ISF cases, in order to assess the need for hospitalization.

Methods

We reviewed the medical charts of 222 children who were hospitalized from 2006 to 2012 with ISF and Glascow Coma Scale—15 at the time of arrival. We collected data regarding demographic characteristics, mechanism of injury, fracture location, clinical symptoms and signs, need for hospitalization, and need for repeated imaging. Data was collected at three time points: at presentation to the emergency room, during hospitalization, and 1 month after admission, when the patients’ parents were asked about the course of the month following discharge.

Results

None of the 222 children included in the study needed neurosurgical intervention. All were asymptomatic 1 month after the injury. Two children underwent repeated head CT due to persistence or worsening of symptoms; these CT scans did not reveal any new findings and did not lead to any intervention whatsoever.

Conclusion

Children arriving at the emergency room with a minor head injury and isolated skull fracture on imaging studies may be considered for discharge after a short period of observation. Discharge should be considered in these cases provided the child has a reliable social environment and responsible caregivers who are able to return to the hospital if necessary. Hospital admission should be reserved for children with neurologic deficits, persistent symptoms, suspected child abuse, or when the parent is unreliable or is unable to return to the hospital if necessary. Reducing unnecessary hospitalizations can prevent emotional stress, in addition to saving costs for the child’s family and the health care system.
  相似文献   
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