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Enhanced expression of vascular endothelial growth factor in lungs of newborn infants with congenital diaphragmatic hernia and pulmonary hypertension 总被引:4,自引:1,他引:4 下载免费PDF全文
BACKGROUND: Pulmonary hypoplasia accompanied by pulmonary hypertension resistant to treatment is an important feature of congenital diaphragmatic hernia (CDH). The pathogenesis of the pulmonary vascular abnormalities in CDH remains to be elucidated at the molecular level. Vascular endothelial growth factor (VEGF), an endothelial cell specific mitogen, is known to play a role in pulmonary angiogenesis and vascular remodelling but there are no data on VEGF expression in patients with CDH. METHODS: Necroscopic lung specimens from 21 patients with CDH with lung hypoplasia and from seven age matched control newborn infants without lung hypoplasia were processed for immunohistochemical analysis using affinity purified anti-human VEGF antibodies. All the cases of CDH had pulmonary hypoplasia, indicated by a lung/body weight index of =0.012, and pulmonary hypertension indicated by repeated cardiac ultrasonography. Cellular localisation of VEGF was semiquantitatively analysed using a staining score ranging from 0 (no staining) to 4 (very strong staining). RESULTS: Significantly raised levels of VEGF immunoreactivity were observed in lung specimens from cases of CDH compared with controls. VEGF was detected mainly in the bronchial epithelium and the medial smooth muscle cells of large (>200 microm) and small (<200 microm) pulmonary arteries, the most intense staining being in the medial smooth muscle cells of the small pulmonary arteries. Endothelial cells were positive for VEGF staining in patients with CDH but not in controls. CONCLUSIONS: This is the first study of VEGF expression in newborn infants with CDH. Increased levels of VEGF, especially in the small, pressure regulating pulmonary arteries, point to a potential role in vascular remodelling. This may reflect an unsuccessful attempt by the developing fetus to increase the pulmonary vascular bed in the hypoplastic lungs to alleviate the associated pulmonary hypertension. 相似文献
94.
INTRODUCTION
Diagnostic errors in orthopaedics are usually caused by missing a fracture or misreading radiographs. The aim of this study was to document the pick-up rate of the wrong diagnoses by reviewing X-rays and casualty notes in the next-day trauma meeting.PATIENTS AND METHODS
The casualty notes and radiographs of 503 patients were prospectively reviewed in the daily trauma meeting between August 2002 and December 2002 in a district general hospital. The relevant data were collected and analysed by a single assessor.RESULTS
The false positive rate for making an orthopaedic diagnosis was 12.6% (i.e.) diagnosing a fracture, when none existed). The false negative (missing) rate was 4%, while 2.4% incidental findings were missed, or at least not documented, after reading the X-rays. There were 7.8% wrong diagnoses made. The majority of the patients were seen by the senior house officers.CONCLUSIONS
The medicolegal significance of false negative diagnosis is obviously greater. In a busy emergency department, where a large number of patients are seen, there is a greater risk. This study shows the importance in a small-to-medium sized accident and emergency unit as well, where there is no senior cover available out-of-hours for final radiological interpretation. A morning trauma meeting which covers reviewing admitted patients as well as non-admission orthopaedic referrals has an effective risk management solution to early detection of missed and wrong diagnoses. 相似文献95.
96.
H. E. de Melker M. A. Conyn-van Spaendonck H. C. R��mke J. K. van Wijngaarden F. R. Mooi J. F. Schellekens 《Emerging infectious diseases》1997,3(2):175-178
In 1996, a sudden increase in pertussis incidence was reported in the Netherlands (2.1 per 100,000 in 1995, 18 per 100,000 in 1996). Although not all potential surveillance artifacts could be excluded, it is highly probable that the data reflect a true outbreak. However, the cause of this increase has not yet been determined. Further research is directed to the severity of disease and a possible mismatch between the vaccine and the circulating Bordetella strains. 相似文献
97.
本实验采用性腺摘除或经假摘除手术的两性SD大鼠,其中部分动物分别予以睾酮(T)或雌二醇(E_2),观察它们在急性饥饿或非饥饿状态下血清T_4、TSH与T浓度变化。结果提示急性饥饿可使雄鼠甲状腺合成或分泌T_4和性腺分泌睾酮减少,从而不完全地抑制了雄激素所介导的对垂体TSH分泌的兴奋作用。外源性T替代虽然可以使去势雄鼠血清T浓度恢复正常,但却无兴奋TSH分泌的作用;饥饿组去势雄鼠接受外源性T后血清TSH更为减少。提示外源性T可抑制此组雄鼠垂体TSH合成及(或)释放。 相似文献
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99.
Sjors FPJ Coppus Jose I Emparanza Julie Hadley Regina Kulier Susanne Weinbrenner Theodoros N Arvanitis Amanda Burls Juan B Cabello Tamas Decsi Andrea R Horvath Marcin Kaczor Gianni Zanrei Karin Pierer Katarzyna Stawiarz Regina Kunz Ben WJ Mol Khalid S Khan 《BMC medical education》2007,7(1):1-10
Background
Little research has been conducted to investigate role stress experienced by faculty members in medical schools in developing countries. This becomes even more important when the process of reform in medical education has already taken place, such as the case of Iran. The objectives of this study were to investigate and assess the level and source of role-related stress as well as dimensions of conflict among the faculty members of Iranian medical schools. Variables like the length of academic work, academic rank, employment position, and the departments of affiliation were also taken into consideration in order to determine potentially related factors.Methods
A survey was conducted at three different ranks of public medical schools. The validated Organizational Role Stress Scale was used to investigate the level of role stress and dimensions of role conflict among medical faculty members. The response rate was 66.5%.Results
The findings show that role stress was experienced in high level among almost all faculty members. All three studied medical schools with different ranks are threatened with relatively the same levels of role stress. Specific differences were found among faculty members from different disciplines, and academic ranks. Also having permanent position and the length of services had significant correlation with the level of role stress. The major role- related stress and forms of conflict among faculty members were role overload, role expectation conflict, inter-role distance, resource inadequacy, role stagnation, and role isolation.Conclusion
The most role-related stressors and forms of conflict among faculty members include too many tasks and everyday work load; conflicting demands from colleagues and superiors; incompatible demands from their different personal and organizational roles; inadequate resources for appropriate performance; insufficient competency to meet the demands of their role; inadequate autonomy to make decision on different tasks; and a feeling of underutilization. The findings of this study can assist administrators and policy makers to provide an attractive working climate in order to decrease side effects and consequences of role stress and to increase productivity of faculty members. Furthermore, understanding this situation can help to develop coping strategies in order to reduce role-related stress. 相似文献100.
Idiopathic thrombocytopenic purpura (ITP) is an autoimmune disorder, occurring predominantly in women. We studied by flow cytofluorimetry the T cell subsets in men and women with ITP and compared them with healthy sex-matched volunteers. In healthy controls, women were found to have higher proportions of T helper/inducer (Th/i) and lower T suppressor/cytotoxic (Ts/c) lymphocytes and consequently higher Th/i:Ts/c ratios than men. Accordingly, in clinical surveys, patients and controls should be matched for sex for proper comparisons. In patients with ITP in its active phase, an imbalance in T cell subsets was found in both sexes. The perturbation was more severe in women who had a marked decrease in number and proportion of Th/i lymphocytes and an increase in the proportion of Ts/c lymphocytes, whereas in men only, the proportion of Th/i lymphocytes was decreased. When patients with active disease were compared to those with ITP in remission, the decrease in Th/i subsets still persisted in both sexes but the Ts/c subset in women had returned to normal proportions. Therefore, the immune imbalance in ITP is more marked in women than men; imbalances in both Th/i and Ts/c are present in women while Ts/c appears not to be involved in men. 相似文献