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Pulmonary arterial hypertension (PAH) is characterized by pulmonary vascular remodeling leading to right ventricular (RV) hypertrophy and failure. Intralipid (ILP), a source of parenteral nutrition for patients, contains γ-linolenic acid and soy-derived phytoestrogens that are protective for lungs and heart. We, therefore, investigated the therapeutic potential of ILP in preventing and rescuing monocrotaline-induced PAH and RV dysfunction. PAH was induced in male rats with monocrotaline (60 mg/kg). Rats then received daily ILP (1 mL of 20% ILP per day IP) from day 1 to day 30 for prevention protocol or from day 21 to day 30 for rescue protocol. Other monocrotaline-injected rats were left untreated to develop severe PAH by day 21 or RV failure by approximately day 30. Saline or ILP-treated rats served as controls. Significant increase in RV pressure and decrease in RV ejection fraction in the RV failure group resulted in high mortality. Therapy with ILP resulted in 100% survival and prevented PAH-induced RV failure by preserving RV pressure and RV ejection fraction and preventing RV hypertrophy and lung remodeling. In preexisting severe PAH, ILP attenuated most lung and RV abnormalities. The beneficial effects of ILP in PAH seem to result from the interplay of various factors, among which preservation and/or stimulation of angiogenesis, suppression and/or reversal of inflammation, fibrosis and hypertrophy, in both lung and RV, appear to be major contributors. In conclusion, ILP not only prevents the development of PAH and RV failure but also rescues preexisting severe PAH.  相似文献   
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Pretreatment with a phytoestrogen genistein has been shown to attenuate the development of pulmonary hypertension (PH). Because PH is not always diagnosed early, we examined whether genistein could also reverse preexisting established PH and prevent associated right heart failure (RHF). PH was induced in male rats by 60 mg/kg of monocrotaline. After 21 days, when PH was well established, rats received daily injection of genistein (1 mg/kg per day) for 10 days or were left untreated to develop RHF by day 30. Effects of genistein on human pulmonary artery smooth muscle cell and endothelial cell proliferation and neonatal rat ventricular myocyte hypertrophy were assessed in vitro. Severe PH was evident 21 days after monocrotaline, as peak systolic right ventricular pressure increased to 66.35±1.03 mm Hg and right ventricular ejection fraction reduced to 41.99±1.27%. PH progressed to RHF by day 30 (right ventricular pressure, 72.41±1.87 mm Hg; RV ejection fraction, 29.25±0.88%), and mortality was ≈75% in RHF rats. Genistein therapy resulted in significant improvement in lung and heart function as right ventricular pressure was significantly reduced to 43.34±4.08 mm Hg and right ventricular ejection fraction was fully restored to 65.67±1.08% similar to control. Genistein reversed PH-induced pulmonary vascular remodeling in vivo and inhibited human pulmonary artery smooth muscle cell proliferation by ≈50% in vitro likely through estrogen receptor-β. Genistein also reversed right ventricular hypertrophy (right ventricular hypertrophy index, 0.35±0.029 versus 0.70±0.080 in RHF), inhibited neonatal rat ventricular myocyte hypertrophy, and restored PH-induced loss of capillaries in the right ventricle. These improvements in cardiopulmonary function and structure resulted in 100% survival by day 30. Genistein restored PH-induced downregulation of estrogen receptor-β expression in the right ventricle and lung. In conclusion, genistein therapy not only rescues preexisting severe PH but also prevents the progression of severe PH to RHF.  相似文献   
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Purpose of Review

Esophageal adenocarcinoma bears one of the fastest rising incidence of any cancers and generally arises in the setting of gastroesophageal reflux and Barrett’s esophagus. However, early detection of neoplasia can be challenging since most patients are asymptomatic until they progress to more advanced and less curable stages, and early dysplastic lesions can be small, multifocal, and difficult to detect. Clearly, new imaging tools are needed in light of sampling error associated with random biopsies, the current standard of practice.

Recent Findings

Advances in endoscopic imaging including virtual chromoendoscopy, confocal laser endomicroscopy, and subsurface imaging with optical coherence tomography have ushered in a new era for detecting subtle neoplastic lesions. Moreover, in light of esophagus-sparing treatments for neoplastic lesions, such tools are likely to guide ablation and follow-up management.

Summary

While there is no ideal single imaging modality to facilitate improved detection, staging, ablation, and follow-up of patients with dysplastic Barrett’s esophagus, new advances in available technology, the potential for multimodal imaging, and the use of computer-aided diagnosis and biomarkers all hold great promise for improving detection and treatment.
  相似文献   
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The antiaging effect of selegiline was reported by several investigators; therefore, there is a growing interest in the potential use of stem cell therapy in aging. In this investigation, selegiline was used to induce neuronal differentiation in undifferentiated pluripotent embryonic stem cells (ESCs). The results show that selegiline can induce neuronal phenotype associated with neurotrophic factor expression. Morphologic and immunohistochemical techniques were used to evaluate the differentiation of the CCE cells, Cresyl violet for the morphologic study, anti-synaptophysin and antityrosine hydroxylase antibodies for characterizing the neuronal phenotype of ESCs, and RT-PCR to study the neurotrophins. The results showed that selegiline can induce dose-dependent ESC differentiation into neurons. Moreover, selegiline can induce neurotrophin expression. This study suggests the potential use of combined selegiline and stem cell therapy to improve deficits in neurodegenerative diseases in aging.  相似文献   
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This study aims to explore and describe nurses' perceptions of their caring behaviors and related factors in several Tehran burn units. Grounded theory was used as the method of analysis. Thirty-eight participants were recruited. Data was generated by unstructured interviews and participant observations, and analyzed by constant comparison. Results revealed that responses to burnout and the type of caring behavior exhibited were affected most markedly by the personal characteristics of nurses and patients and the interaction between these two factors. Long-standing and intense organizational pressures in the burn units of Tehran, in addition to the sensitivity of nurses' characteristics to these pressures, suggest that attributing more importance to the social, political and ethical aspects of caring may aid in executing stress reduction programs and improving nurses' morale.  相似文献   
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Objective

To assess trends in caesarean delivery and its associated factors in south-western Iran.

Subjects and Methods

This cross-sectional study was conducted from January 2007 to January 2010 in Fars province, Iran. All deliveries recorded in public and private hospitals were included. The Mann-Whitney U test, χ2 test and multivariate logistic regression models were used for analysis of data. A p value less than 0.05 was considered significant.

Results

The rate of caesarean section for the whole sample of 139,159 increased from 51.6% in 2007 to 53.3% in 2009, which was statistically and clinically significant. The rate of caesarean delivery was significantly higher in primiparous compared to multiparous mothers. The rate increased steadily with the mother''s age. The most prevalent recorded reason for caesarean delivery was maternal request. Logistic regression analysis showed that maternal age, previous abortions, underlying maternal disease, gestational age and number of living children were key contributing factors to the choice of mode of delivery.

Conclusion

This study showed an increasing rate of caesarean delivery which should draw the attention of policymakers to factors associated with this mode of delivery.Key Words: Caesarean delivery, Iran, Trend  相似文献   
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