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1.
We studied the effects of 15(R)-15-methyl prostaglandin E2 (arbaprostil) on gastric secretion and various acute and chronic gastric lesions produced in rats. Arbaprostil significantly inhibited gastric secretion in 4 hr-pylorus-ligated preparations when given intraduodenally in a dose of 30 or 100 micrograms/kg. The agent, however, significantly stimulated gastric secretion of rats with either a ligated or intact pylorus when given orally in doses of 3-100 micrograms/kg. Orally administered arbaprostil dose-dependently prevented the development of HCI-ethanol-, histamine-, water-immersion stress-, or indomethacin-induced gastric erosions. Intraduodenally administered arbaprostil also dose-dependently prevented the development of aspirin-induced gastric erosions in pylorus-ligated rats. Arbaprostil, given orally in doses of 1-100 micrograms/kg twice daily for 2 weeks, had little or no effect on the healing of acetic acid-induced gastric ulcers. However, oral administration of the agent in a dose of 3 or 10 micrograms/kg twice daily for 4 weeks significantly accelerated the healing of acetic acid-induced gastric ulcers. The increase in doses up to 100 micrograms/kg twice daily for 4 weeks had no effect on ulcer healing. These results indicate that arbaprostil, at either antisecretory or even acid stimulating doses, is effective in preventing the development of acute gastric erosions and in accelerating the healing of chronic gastric ulcers.  相似文献   
2.
Van der Waals (vdW) interactions are ubiquitous in molecules and condensed matter, and play a crucial role in determining the structure, stability, and function for a wide variety of systems. The accurate prediction of these interactions from first principles is a substantial challenge because they are inherently quantum mechanical phenomena that arise from correlations between many electrons within a given molecular system. We introduce an efficient method that accurately describes the nonadditive many-body vdW energy contributions arising from interactions that cannot be modeled by an effective pairwise approach, and demonstrate that such contributions can significantly exceed the energy of thermal fluctuations-a critical accuracy threshold highly coveted during molecular simulations-in the prediction of several relevant properties. Cases studied include the binding affinity of ellipticine, a DNA-intercalating anticancer agent, the relative energetics between the A- and B-conformations of DNA, and the thermodynamic stability among competing paracetamol molecular crystal polymorphs. Our findings suggest that inclusion of the many-body vdW energy is essential for achieving chemical accuracy and therefore must be accounted for in molecular simulations.  相似文献   
3.
Genital papilloma is caused by human papilloma virus (HPV) infection and recurs frequently. Although T cells are known to play a critical role in the control of HPV infection and papilloma development, the function and phenotype of these cells in the lesion remain to be elucidated. In the present study, we examined the function and phenotype of CD4+ T cells isolated from the lesions of primary (n = 9) and recurrent (n = 11) genital papillomas. In recurrent papillomas, the frequency of proliferating (Ki-67+) CD4+ T cells was significantly reduced compared with primary papillomas. Cytokine production was evaluated by intracellular cytokine staining in anti-CD3/anti-CD28-stimulated CD4+ T cells. CD4+ T cells from recurrent lesions showed impaired production of IL-2, IFN-γ, and TNF-α. Of interest, the frequency of cytokine-producing CD4+ T cells significantly correlated with the frequency of Ki-67+CD4+ T cells. We also studied expression of programmed death-1 (PD-1), a T-cell exhaustion marker. The frequency of PD-1+CD4+ T cells was significantly increased in recurrent lesions and inversely correlated with the frequency of cytokine-producing CD4+ T cells. The functional significance of PD-1 expression was determined in blocking assays with anti-PD-L1, which restored cytokine production of CD4+ T cells from recurrent lesions. Taken together, in recurrent genital papilloma lesions, proliferation, and cytokine production by CD4+ T cells are impaired and the PD-1/PD-L1 interaction is responsible for the functional impairment of CD4+ T cells.  相似文献   
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Objective

To compare two forms of device-specific training – body-weight-supported (BWS) ambulation on a fixed track (TRK) and BWS ambulation on a treadmill (TM) – to comprehensive physical therapy (PT) for improving walking speed in persons with chronic, motor-incomplete spinal cord injury (SCI).

Methods

Thirty-five adult subjects with a history of chronic SCI (>1 year; AIS ‘C’ or ‘D’) participated in a 13-week (1 hour/day; 3 days per week) training program. Subjects were randomized into one of the three training groups. Subjects in the two BWS groups trained without the benefit of additional input from a physical therapist or gait expert. For each training session, performance values and heart rate were monitored. Pre- and post-training maximal 10-m walking speed, balance, muscle strength, fitness, and quality of life were assessed in each subject.

Results

All three training groups showed significant improvement in maximal walking speed, muscle strength, and psychological well-being. A significant improvement in balance was seen for PT and TRK groups but not for subjects in the TM group. In all groups, post-training measures of fitness, functional independence, and perceived health and vitality were unchanged.

Conclusions

Our results demonstrate that persons with chronic, motor-incomplete SCI can improve walking ability and psychological well-being following a concentrated period of ambulation therapy, regardless of training method. Improvement in walking speed was associated with improved balance and muscle strength. In spite of the fact that we withheld any formal input of a physical therapist or gait expert from subjects in the device-specific training groups, these subjects did just as well as subjects receiving comprehensive PT for improving walking speed and strength. It is likely that further modest benefits would accrue to those subjects receiving a combination of device-specific training with input from a physical therapist or gait expert to guide that training.  相似文献   
7.
Objective: The purpose of the study was to assess impact of vitamin D supplements on the disease progression and overall health of osteoarthritis (OA) patients.

Methodology: A cohort study was carried out for 8?months (August 2017–March 2018) in the Orthopedics Department of Kasturba Hospital, Manipal, India, a tertiary care hospital. One hundred and forty-two patients who were diagnosed with OA (grades 1–3) with low serum 25(OH)D levels (severely deficient, deficient, or insufficient) were selected for the study. These patients were categorized into two cohorts: a control cohort (CC) and a study cohort (SC). CC members were patients (n?=?71) who had not received vitamin D supplements, and SC members were patients (n?=?71) who had received vitamin D supplements. Severity grading of OA, pain score, and health assessment were performed using the Kellgren–Laurence grading score, visual analogue scale (VAS), and WOMAC, respectively, at baseline and after 3?months of follow-up.

Results: Subjects in the both CC and SC reported no statistically significant difference (similar in both group) in severity grade (p?=?0.303), pain score (p?=?0.099), parathyroid hormone (PTH) (p?=?0.083), and health status (p?=?0.76) at baseline. After 3?months of follow-up (post vitamin D supplementation), OA patients have shown statistically significant difference in severity grades, serum 25(OH)D status, PTH level (p?<?0.001), and overall health status (p?=?0.001) in the SC with respect to baseline. Likewise, percentage distribution of positive changes was significantly higher in severity grade, pain score, serum 25(OH)D level, overall health status (p?<?0.001), and PTH (p?=?0.040) of SC as compared to CC at follow-up.

Conclusion: Vitamin D supplements have significantly improved serum 25(OH)D levels, PTH, severity grade, and pain score of OA patients. Most importantly, vitamin D supplements have shown improvement in the overall health of OA patients, emphasizing the place of vitamin D supplements in the management of OA.

Clinical Trial Registry-India (CTRI) registration no: CTRI/2017/12/011031  相似文献   

8.
Altered immunologic reactions were observed in breast cancer patients as compared to those in normal subjects. Lymphoproliferative responses to murine mammary tumor virus (MuMTV) were significantly enhanced in peripheral blood mononuclear cells from patients with metastatic disease. These reactivities occurred with mammary tumor virus purified from either mouse milk or infected feline kidney cells but not with Rauscher murine leukemia virus. For the assessment of the role of peripheral blood mononuclear leukocyte subpopulations in the responsiveness to MuMTV, the cell preparations were fractionated according to their ability to form spontaneous rosettes with sheep red blood cells (E-rosettes). The effectiveness of the separation was ascertained by means of cell surface markers, i.e., presence of surface immunoglobulins or a T-cell marker. Leu-1 antigen, and mitogen-induced blastogenesis. The responsiveness to the MuMTV antigen(s) was associated with the T-cell subset, identified as the E-rosetting. Leu-1-positive, and surface immunoglobulin-negative population. Although some subjects with the normal population gave positive reactions, the results reveal an apparent association between high levels of responsiveness to MuMTV within the T-lymphocyte subset and breast cancer disease.  相似文献   
9.
Although T cells are known to be involved in the pathogenesis of coronary artery disease, it is unclear which subpopulation of T cells contributes to pathogenesis in acute myocardial infarction (MI). We studied the immunological characteristics and clinical impact of CD8+CD57+ T cells in acute MI patients. The frequency of CD57+ cells among CD8+ T cells was examined in peripheral blood sampled the morning after acute MI events. Interestingly, the frequency of CD57+ cells in the CD8+ T-cell population correlated with cardiovascular mortality 6 months after acute MI. The immunological characteristics of CD8+CD57+ T cells were elucidated by surface immunophenotyping, intracellular cytokine staining and flow cytometry. Immunophenotyping revealed that the CD8+CD57+ T cells were activated, senescent T cells with pro-inflammatory and tissue homing properties. Because a high frequency of CD8+CD57+ T cells is associated with short-term cardiovascular mortality in acute MI patients, this specific subset of CD8+ T cells might contribute to acute coronary events via their pro-inflammatory and high cytotoxic capacities. Identification of a pathogenic CD8+ T-cell subset expressing CD57 may offer opportunities for the evaluation and management of acute MI.  相似文献   
10.
Studies of working memory load effects on human EEG power have indicated divergent effects in different frequency bands. Although gamma power typically increases with load, the load dependency of the lower frequency theta and alpha bands is uncertain. We obtained intracranial electroencephalography measurements from 1453 electrode sites in 14 epilepsy patients performing a Sternberg task, in order to characterize the anatomical distribution of load-related changes across the frequency spectrum. Gamma power increases occurred throughout the brain, but were most common in the occipital lobe. In the theta and alpha bands, both increases and decreases were observed, but with different anatomical distributions. Increases in theta and alpha power were most prevalent in frontal midline cortex. Decreases were most commonly observed in occipital cortex, colocalized with increases in the gamma range, but were also detected in lateral frontal and parietal regions. Spatial overlap with group functional magnetic resonance imaging results was minimal except in the precentral gyrus. These findings suggest that power in any given frequency band is not a unitary phenomenon; rather, reactivity in the same frequency band varies in different brain regions, and may relate to the engagement or inhibition of a given area in a cognitive task.  相似文献   
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