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91.
92.

BACKGROUND

Many state agencies have developed model wellness policies (MWPs) to serve as examples for schools when writing their own school wellness policy (SWP). The purpose of this study was to evaluate if a MWP aids schools in writing stronger, more comprehensive SWPs.

METHODS

For this cross‐sectional study, 91 school districts submitted their current SWP and completed a survey that classified districts into either districts that utilized the state MWP (N = 56; 61.5%) or those that did not (NMWP, N =35; 38.5%). The Wellness School Assessment Tool (WellSAT) was used to assess the strength, comprehensiveness, total overall score, and subsection scores of each policy. Dependent variables were compared between groups using t tests. Statistical significance was set at p ≤ .05. Data are presented as mean ±SD.

RESULTS

No significant differences were found between groups in total overall (MWP 76.8 ± 37.9; NMWP 62.1 ± 34.3), strength (MWP 25.3 ± 17.6; NMWP 19.1 ± 12.8), or comprehensiveness scores (MWP 51.5 ± 21.2; NMWP 43.0 ± 22.1). The only subsection score difference identified between groups was the Nutrition Standards comprehension score (p = .02).

CONCLUSIONS

These data suggest MWPs may not improve the quality of written SWPs. Further research is needed to better understand the needs of school districts in SWP development.
  相似文献   
93.
HIV controllers: how do they tame the virus?   总被引:2,自引:0,他引:2  
HIV controllers are rare, chronically HIV-1-infected patients in whom viral replication is undetectable in the absence of antiretroviral treatment. Most such patients are nonetheless infected by replication-competent viruses. An effective, multifunctional HIV-specific CD8(+) T-cell response is thought to be central to viral control in these individuals. The mechanisms underlying this spontaneous control of HIV infection and the particular characteristics of the CD8(+) T-cell response in HIV controllers are the focus of intensive investigations, because they should help to unravel the pathogenesis of AIDS and to provide new clues for the design of effective vaccine strategies. In this review, we examine recent findings from these studies.  相似文献   
94.
A transfusion reaction in a 76-year-old man was followed by severe but transient thrombocytopenia after infusion of whole blood. A high-titer platelet-specific antibody (anti-PLA) was demonstrated in the plasma of the implicated unit and in the serum of the blood donor. In addition, three previous recipients of blood from the implicated donor had posttransfusion episodes of unexplained thrombocytopenia. These cases represent the first reported clinical examples of posttransfusion thrombocytopenia caused by passively transfused platelet-specific alloantibodies.  相似文献   
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97.
Neonatal screening for congenital adrenal hyperplasia (CAH) is useful in diagnosing salt wasting form (SW). However, there are difficulties in interpreting positive results in asymptomatic newborns. The main objective is to analyze genotyping as a confirmatory test in children with neonatal positive results. Patients comprised 23 CAH children and 19 asymptomatic infants with persistently elevated 17‐hydroxyprogesterone (17OHP) levels. CYP21A2 gene was sequenced and genotypes were grouped according to the enzymatic activity of the less severe allele: A1 null, A2 < 2%, B 3–7%, C > 20%. Twenty‐one children with neonatal symptoms and/or 17OHP levels > 80 ng/ml carried A genotypes, except two virilized girls (17OHP < 50 ng/ml) without CAH genotypes. Patients carrying SW genotypes (A1, A2) and low serum sodium levels presented with neonatal 17OHP > 200 ng/ml. Three asymptomatic boys carried simple virilizing genotypes (A2 and B): in two, the symptoms began at 18 months; another two asymptomatic boys had nonclassical genotypes (C). The remaining 14 patients did not present CAH genotypes, and their 17OHP levels were normalized by 14 months of age. Molecular analysis is useful as a confirmatory test of CAH, mainly in boys. It can predict clinical course, identify false‐positives and help distinguish between clinical forms of CAH.  相似文献   
98.
Abstract: Background: Abrikossoff or granular cell tumour (GCT) is a relatively rare neoplasia, benign in most of the cases. It may occur in any part of the human body, but it has an oral location in 70% of the cases. Its origin has been discussed for decades, and it is not yet definitively determined. Immunohistochemical techniques suggest its origin in the Schwann cells, while more recent studies with new markers indicate an origin related to neuroendocrine cells. Objective: Contribute to the clarification of histogenesis of oral Abrikossoff tumour studying immunohistochemical marking of 11 oral Brazilian cases. Materials and methods: Samples of tissues from the oral mucosa, tongue and lips placed in paraffin blocks, from eleven patients with a histopathological diagnosis of benign GCT were studied. Four different anti‐serums (S‐100, vimentin, PGP9.5 and ENE) were used for immunoperoxydase technique. Results: A clear positivity for S‐100 protein and vimentin was observed, with markers indicating origin from the Schwann cells. Less intense positivity was found in some cases, for ENE and PGP9.5, which suggests a neuroendocrine origin. Conclusions: The results obtained suggest an origin from Schwann cells, but also arise the possibility of neuroendocrine origin. New methods and more specific immunohistochemical markers are needed to elucidate the origin of the Abrikossoff tumour.  相似文献   
99.
Background:  Magnetoencephalography (MEG) is increasingly used in the presurgical evaluation of pediatric seizure patients. Many pediatric patients require sedation or anesthesia to tolerate these exams. However, the available literature on anesthetic management in this population is very limited.
Methods:  We retrospectively reviewed the records of all patients who underwent MEG scanning at our institution with regard to the interaction of anesthetic management and quality of scan data.
Results:  High-dose propofol infusions (≥200 μg·kg−1·min−1) were associated with high frequency artifacts that interfered with the identification of epileptiform discharges. Lower-dose propofol infusions (≤100 μg·kg−1·min−1) did not produce artifacts but required co-administration of fentanyl to prevent patient motion. Dexmedetomidine infusions were not associated with signal artifacts and prevented patient motion very well in our initial patients and became our standard technique.
Conclusion:  In our experience, dexmedetomidine infusions are preferable to propofol-based techniques for pediatric MEG scans due to the absence of adverse effect on interictal activity.  相似文献   
100.
Mercury is known to cause harmful neural effects affecting the cardiovascular system. Here, we evaluated the chronic effects of low‐dose mercury exposure on the autonomic control of the cardiovascular system. Wistar rats were treated for 30 days with HgCl2 (1st dose 4.6 μg/kg followed by 0.07 μg/kg per day, intramuscular) or saline. The femoral artery and vein were then cannulated for evaluation of autonomic control of the hemodynamic function, which was evaluated in awake rats. The following tests were performed: baroreflex sensitivity, Von Bezold‐Jarisch reflex, heart rate variability (HRV) and pharmacological blockade with methylatropine and atenolol to test the autonomic tone of the heart. Exposure to HgCl2 for 30 days slightly increased the mean arterial pressure and heart rate (HR). There was a significant reduction in the baroreflex gain of animals exposed to HgCl2. Moreover, haemodynamic responses to the activation of the Von Bezold‐Jarisch reflex were also reduced. The changes in the spectral analysis of HRV suggested a shift in the sympathovagal balance toward a sympathetic predominance after mercury exposure, which was confirmed by autonomic pharmacological blockade in the HgCl2 group. This group also exhibited reduced intrinsic HR after the double block suggesting that the pacemaker activity of the sinus node was also affected. These findings suggested that the autonomic modulation of the heart was significantly altered by chronic mercury exposure, thus reinforcing that even at low concentrations such exposure might be associated with increased cardiovascular risk.  相似文献   
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