首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   114篇
  免费   9篇
  国内免费   1篇
耳鼻咽喉   1篇
儿科学   6篇
妇产科学   8篇
基础医学   10篇
口腔科学   2篇
临床医学   11篇
内科学   24篇
皮肤病学   2篇
神经病学   3篇
特种医学   7篇
外科学   10篇
综合类   5篇
预防医学   7篇
药学   22篇
中国医学   1篇
肿瘤学   5篇
  2022年   2篇
  2021年   10篇
  2020年   5篇
  2019年   9篇
  2018年   6篇
  2017年   6篇
  2016年   7篇
  2015年   4篇
  2014年   6篇
  2013年   5篇
  2012年   9篇
  2011年   5篇
  2010年   4篇
  2009年   6篇
  2008年   4篇
  2007年   6篇
  2006年   8篇
  2005年   8篇
  2004年   5篇
  2003年   2篇
  2002年   1篇
  1999年   2篇
  1988年   1篇
  1970年   1篇
  1969年   1篇
  1964年   1篇
排序方式: 共有124条查询结果,搜索用时 15 毫秒
1.
Recent studies have provided evidence that macrophages from Th1-prone mouse strains respond with an M1 profile, and macrophages from Th2-prone mouse strains respond with an M2 profile, characterized by the dominant production of NO or TGF-beta 1, respectively. We have shown that peritoneal macrophages from IL-12p40 gene knockout mice have a bias toward the M2 profile, spontaneously secreting large amounts of TGF-beta 1 and responding to rIFN-gamma with weak NO production. Moreover, IL-12p40KO macrophages are more permissive to Trypanosoma cruzi replication than their wild-type littermate cells. Prolonged incubation with rIL-12 fails to reverse the M2 polarization of IL-12p40KO macrophages. However, TGF-beta 1 is directly implicated in sustaining the M2 profile because its inhibition increases NO release from IL-12p40KO macrophages. IFN-gamma deficiency is apparently not the reason for TGF-beta 1 up-regulation, because rIFN-gamma KO macrophages produce normal amounts of this cytokine. These findings raise the possibility that IL-12 has a central role in driving macrophage polarization, regulating their intrinsic ability to respond against intracellular parasites.  相似文献   
2.
Ginkgo biloba extract (GbE) was assessed in models of acute inflammation induced by carrageenan, formalin or capsaicin in the rat, in models of nociceptive pain, such as hot-plate (55 degrees C) latency, tail-electric stimulation assay and capsaicin-induced paw licking and in the model of acute gastric damage induced by indomethacin. The agent showed marked anti-inflammatory activity in the carrageenan model of paw oedema. When given subcutaneously (s.c.) (25 and 50 mg kg(-1)) 30 min before challenge, GbE inhibited paw oedema with a maximal effect of 43.7 and 56.9%, respectively, at 2h post-carrageenan. Significant inhibition of oedema was also observed when GbE (50 mg kg(-1), s.c.) was given 30 min after carrageenan challenge. The agent was also active p.o. in acute inflammation caused by carrageenan. The administration of GbE with indomethacin, rofecoxib, celecoxib, dexamethasone or melatonin resulted in an additive effect. GbE (50 mg kg(-1), s.c.) caused significant inhibition of formalin-induced paw oedema, but did not reduce the capsaicin-induced paw oedema. In tests of nociception, GbE (25, 50 or 100 mg kg(-1)) decreased in dose-dependent manner the capsaicin-induced hind paw licking time and was similarly effective in the hot-plate assay of nociception. In contrast, when assessed in the tail-electric stimulation test, GbE was only effective in the highest dose (100 mg kg(-1)). In pylorus-ligated rats, GbE (25 or 50 mg kg(-1)) increased gastric acid secretion, but reduced gastric mucosal damage caused by IND. Results suggest that GbE may be of clinical value as an anti-inflammatory and analgesic drug alone or in conjunction with NSAIDs.  相似文献   
3.
Cancer is the major cause of death and many factors that lead to its occurrences, such as environmental pollution and pesticides and other factors. Ehrlich carcinoma development depends on many things associated with the environment, nutrition, personal habits, and family history. The present study aimed to evaluate the potential protective effects of vitamin B17 (VB17) against Ehrlich ascites carcinoma (EAC) that induced kidney toxicity in female mice. The mice were divided into five groups (first group, control group; second group, VB17 group; third group, EAC group; fourth group, pretreated EAC with VB17; fifth group, cotreated EAC with VB17). Results showed the VB17 in pretreated (G4) and cotreated (G5) groups lead to an improvement in DNA damage and cytological examination, in addition significantly (P < .05) increase in Na+, red blood cell, hemoglobin, hematocrit value, mean corpuscular hemoglobin (MCH), and MCH concentration, whereas significantly (P < .05) decrease in urea, creatinine, K+, platelets, and white blood cells while insignificant (P < .05) changes in mean corpuscular volume when compared to the EAC group. Many histopathological changes were observed in kidney sections in EAC as marked damage and degenerated, glomerular atrophy, the Malpighian corpuscles that lost their characteristic configuration. On the other hand, a moderate improvement and arrangement in the kidney histological structure in pretreated VB17 + EAC, while a mild enhancement and arrangement of the kidney structure in cotreated EAC + VB17. In addition, depletion in renal P53 and PCNA protein expression compared with the EAC group. It could be concluded that VB17 has a potential renal protective effect against EAC cells induced kidney injury.  相似文献   
4.
Objectives:To elucidate the risk factors for hospital admission among COVID-19 patients with type 2 diabetes mellitus (T2DM).Methods:This retrospective study was conducted at the Prince Sultan Military Medical City, Riyadh, Saudi Arabia between May 2020 and July 2020. Out of 7,260 COVID-19 patients, 920 were identified as T2DM. After the exclusion process, 806 patients with T2DM were included in this analysis. Patients’ data were extracted from electronic medical records. A logistic regression model was performed to estimate the risk factors of hospital admission.Results:Of the total of 806 COVID-19 patients with T2DM, 48% were admitted in the hospital, 52% were placed under home isolation. Older age between 70-79 years (OR [odd ratio] 2.56; p=0.017), ≥80 years (OR 6.48; p=0.001) were significantly more likely to be hospitalized compared to <40 years. Similarly, patients with higher HbA1c level of ≥9% compared to <7%; (OR 1.58; p=0.047); patients with comorbidities such as, hypertension (OR 1.43; p=0.048), cardiovascular disease (OR 1.56; p=0.033), cerebrovascular disease (OR 2.38; p=0.016), chronic pulmonary disease (OR 1.51; p=0.018), malignancy (OR 2.45; p=0.025), chronic kidney disease (CKD) IIIa, IIIb, IV (OR 2.37; p=0.008), CKD V (OR 5.07; p=0.007) were significantly more likely to be hospitalized. Likewise, insulin-treated (OR 1.46; p=0.03) were more likely to require hospital admission compared to non-insulin treated patients.Conclusion:Among COVID-19 patients with diabetes, higher age, high HbA1c level, and presence of other comorbidities were found to be significant risk factors for the hospital admission.  相似文献   
5.
The endophytic fungus Aspergillus is considered as an enormous source of chemical leads with promising biological activities. Different Aspergillus species have proved their ability to produce plenty of secondary metabolites including butenolides, alkaloids, terpenoids, cytochalasins, phenalenones, ρ-terphenyls, xanthones, sterols, diphenyl ether and anthraquinone derivatives with diverse biological activities, such as anti-cancer, antifungal, anti-bacterial, anti-viral, anti-inflammatory, antitrypanosomal and antileishmanial activities. From January 2015 until December 2019, three hundred and sixty-one secondary metabolites were reported from different endophytic Aspergillus species. This review discusses the isolated secondary metabolites from different endophytic Aspergillus species reported from January 2015 to December 2019 along with their reported biological activities and structural aspects whenever applicable.

The endophytic fungus Aspergillus is the precious source of chemical biodiversity.  相似文献   
6.
Optimal nutrition is critical to the attainment of healthy growth, human capital and sustainable development. In Egypt, infants and young children face overlapping forms of malnutrition, including micronutrient deficiencies, stunting and overweight. Yet, in this setting, little is known about the factors associated with growth during the first year of life. A rise in stunting in Lower Egypt from 2005 to 2008 prompted this implementation research study, which followed a longitudinal cohort of infants from birth to 1 year of age within the context of a USAID‐funded maternal and child health integrated programme. We sought to determine if growth patterns and factors related to early growth differed in Lower and Upper Egypt, and examined the relationship between weight loss and subsequent stunting at 12 months of age. Growth patterns revealed that length‐for‐age z‐score (LAZ) decreased and weight‐for‐length z‐score (WLZ) increased from 6 to 12 months of age in both regions. One‐quarter of infants were stunted and nearly one‐third were overweight by 12 months of age in lower Egypt. Minimum dietary diversity was significantly associated with WLZ in Lower Egypt (β = 0.22, P < 0.05), but not in Upper Egypt. Diarrhoea, fever and programme exposure were not associated with any growth outcome. Weight loss during any period was associated with a twofold likelihood of stunting at 12 months in Lower Egypt, but not Upper Egypt. In countries, like Egypt, facing the nutrition transition, infant and young child nutrition programmes need to address both stunting and overweight through improving dietary quality and reducing reliance on energy‐dense foods.  相似文献   
7.
8.
In sickle cell disease (SCD), ocular lesions result from stasis and occlusion of small eye vessels by sickled erythrocytes. Vaso-occlusive disease of the retina can be responsible for nonproliferative (NPR) and proliferative retinopathy (PR). Patients are often asymptomatic until serious complications arise as, vitreous hemorrhage and retinal detachment. This work aimed to study the frequency and pattern of ocular manifestations in Egyptian children and young adults with SCD. In this cross-sectional study, 40 steady state patients (80 eyes) aged 2–28 years (30 children and 10 young adults) with established diagnosis of SCD (26 with homozygous SS and 14 with S/β thalassemia underwent complete ophthalmic examination with dilated fundoscopy. Fluorescein angiography was performed for patients ≥12 years old. The overall frequency of retinal lesions was 47.5 % (46.2 and 50 % of SS and S/β patients respectively). PR and NPR were evident in 32.5 and 27.5 % of all enrolled patients respectively (five patients having both). Peripheral retinal occlusion was a frequent ocular finding in both groups; the youngest patient showing PR was 15 years old. Older age, longer disease duration and splenectomy were significantly more prevalent among patients with PR. Despite lack of visual symptoms, children and young adults are at risk of PR. Frequency of retinal lesions was comparable in SS and S/β patients. Periodic ophthalmologic examination starting at the age of 12 years is recommended for timely-identification of retinal lesions thus minimizing the risk of sight threatening retinopathy.  相似文献   
9.
10.
ObjectivesTo test if treatment of polycystic ovary (PCO) infertile patients with clomiphene citrate (CC) and the nitric oxide (NO) donors isosobid mononitrate (ISMN) might improve the ovulation and pregnancy rates compared to treatment with CC alone.Study designProspective, randomized, controlled study.SettingBenha university hospital. January 2008 to January 2009.Subjects and methodsThe study included thirty PCO infertile patients divided randomly into a control and a study groups each fifteen cases. Patients in the control group were treated with 100mg CC for five days starting from the fifth day of the cycle. The study group received in addition to CC, 20mg ISMN tablet applied vaginally till the diagnosis of ovulation and pregnancy.Primary outcome measuresOvulation and pregnancy rate in the CC+ISMN group compared to the CC alone group.Secondary outcome measuresNumber of mature follicles (?18mm), cervical mucus score and endometrial thickness in both groups.ResultsThere was a significant increase in the ovulation and pregnancy rates in the CC+ISMN group. The number of mature follicles, the cervical mucus score and the endometrial thickness were significantly higher in this group.ConclusionsThis novel treatment of infertile PCO patients with combination of CC and NO donors is simple and promising. The ovulation and pregnancy rates are increased due to improvement of follicular maturation, cervical mucus quality and endometrial receptivity.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号