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   235篇
  免费   15篇
  国内免费   2篇
耳鼻咽喉   9篇
儿科学   6篇
妇产科学   11篇
基础医学   36篇
口腔科学   9篇
临床医学   33篇
内科学   29篇
神经病学   26篇
特种医学   20篇
外科学   18篇
综合类   5篇
预防医学   18篇
眼科学   3篇
药学   17篇
中国医学   6篇
肿瘤学   6篇
  2023年   2篇
  2022年   15篇
  2021年   13篇
  2020年   15篇
  2019年   20篇
  2018年   11篇
  2017年   14篇
  2016年   3篇
  2015年   5篇
  2014年   6篇
  2013年   20篇
  2012年   10篇
  2011年   11篇
  2010年   4篇
  2009年   1篇
  2008年   8篇
  2007年   14篇
  2006年   3篇
  2005年   3篇
  2004年   13篇
  2003年   7篇
  2002年   3篇
  2001年   1篇
  2000年   4篇
  1999年   2篇
  1998年   2篇
  1996年   3篇
  1995年   2篇
  1994年   7篇
  1992年   1篇
  1991年   5篇
  1990年   2篇
  1989年   4篇
  1987年   1篇
  1985年   2篇
  1984年   3篇
  1983年   3篇
  1980年   1篇
  1979年   2篇
  1978年   2篇
  1968年   1篇
  1967年   2篇
  1946年   1篇
排序方式: 共有252条查询结果,搜索用时 0 毫秒
11.
Posterior reversible encephalopathy syndrome is a rare underestimated condition, that generally complicates a rise in blood pressure in an acute setting. This entity has been increasingly identified in patients with systemic lupus erythematosus disease. PRES is challenging to diagnose seeing as it presents with nonspecific neurological symptoms, such as head-aches, confusion, seizures, visual changes or a coma, and can mimic neuropsychiatric lupus. Imaging plays a necessary role in confirming this diagnosis, as it is characterized by vasogenic edema of the posterior white matter, in which the distribution is bilateral and symmetrical. Although this syndrome is rare, early diagnosis allows a prompt treatment and therefore a favorable outcome. We present a case report of PRES in a 14-year-old female previously diagnosed with lupus nephropathy, who presented to the emergency department with seizures and uncontrolled hypertension, that was unfortunately not reversible is this patient.  相似文献   
12.
In chemical industry, usual solvents are being replaced by supercritical fluids. Last few years, extraction by these environmentally benign solvents has had much attention and now is considered as the newest separation technology. However, developing new applications and improving existing ones is based on a set of thermodynamic and physical properties of pure solutes related to phase equilibrium for which experimental values cannot be found and consequently, there is an increase need for accurate estimates of these properties. This paper is interested firstly to a thermodynamic property which is the Krichevskii parameter and secondly to a thermophysical one which is the sublimation pressure. First parameter is considered as a governor of thermodynamic properties in binary dilute mixtures near the solvent's critical point and can be calculated from some rigorous relationships and in this paper a review and a new way for its estimation are presented based on consistency of solid's solubility data in supercritical fluids and dilute solution theory. Second parameter is considered as the predominant influencer on solubility in supercritical fluids and unavailability of its experimental values presents an obstacle to thermodynamic modeling of solubility data. For this reason and as a second step, in this paper we present a new manner for its estimation. Obtained results are relevant, very promising for each considered property and the methodology can be applied for other solutes with more complex structures as Pharmaceuticals (antibiotics, drugs, anti-inflammatories …), polycyclic aromatic hydrocarbons (PAHC) and dyestuffs.  相似文献   
13.
M H Mansour  R El Ridi    N Badir 《Immunology》1980,40(4):605-611
A specific antiserum was raised in rabbits against thymocytes from snakes, Spalerosophis diadema, and was absorbed repeatedly with snake erythrocytes and kidney cells. In complement-dependent cytotoxicity assays, the absorbed anti-thymocyte serum (ATS) was, at any given dilution, cytotoxic to Sp. diadema thymocytes > peripheral blood lymphocytes (PBL) > spleen cells and could be titrated to a plateau defining a population of about 98% of thymocytes, 80% of PBL and 72% of spleen cells. Antiserum directed against snake immunoglobulins was obtained by injecting rabbits with gamma-globulins separated from snake serum by DEAE-cellulose filtration. the anti-gamma globulin serum was absorbed with snake erythrocytes, and in indirect membrane immunofluorescence stained no thymocytes while reacted with about 15% of PBL and 29% of spleen lymphocytes up to a 1:8 dilution. Fluorescence of positive cells was distributed in spots, patches or caps; cap formation could be inhibited by maintaining the immunofluorescence test at +4 degrees. In each of six separate experiments performed during spring, the percentage of lymphocytes which reacted with anti-snake gamma-globulin serum complemented the percentage of cells recognized by ATS. It was shown, furthermore, that about 3%, 8% and 21% of lymphocytes from thymus, peripheral blood and spleen, respectively, possess a receptor for 2-mercaptoethanol-insensitive antibody-sheep erythrocyte complexes. The results indicate that lymphocyte structural heterogeneity exists in reptiles.  相似文献   
14.
Aggregatibacter actinomycetemcomitans is frequently associated with localized aggressive periodontitis (LAP); however, longitudinal cohort studies relating A. actinomycetemcomitans to initiation of LAP have not been reported. A periodontal assessment was performed on 1,075 primarily African-American and Hispanic schoolchildren, ages 11 to 17 years. Samples were taken from each child for A. actinomycetemcomitans. A cohort of 96 students was established that included a test group of 38 A. actinomycetemcomitans-positive students (36 periodontally healthy and 2 with periodontal pockets) and 58 healthy A. actinomycetemcomitans-negative controls. All clinical and microbiological procedures were repeated at 6-month intervals. Bitewing radiographs were taken annually for definitive diagnosis of LAP. At the initial examination, clinical probing attachment measurements indicated that 1.2% of students had LAP, while 13.7% carried A. actinomycetemcomitans, including 16.7% of African-American and 11% of Hispanic students (P = 0.001, chi-square test). A. actinomycetemcomitans serotypes a, b, and c were equally distributed among African-Americans; Hispanic students harbored predominantly serotype c (P = 0.05, chi-square test). In the longitudinal phase, survival analysis was performed to determine whether A. actinomycetemcomitans-positive as compared to A. actinomycetemcomitans-negative students remained healthy ("survived") or progressed to disease with attachment loss of >2 mm or bone loss (failed to "survive"). Students without A. actinomycetemcomitans at baseline had a significantly greater chance to remain healthy (survive) compared to the A. actinomycetemcomitans-positive test group (P = 0.0001). Eight of 38 A. actinomycetemcomitans-positive and none of 58 A. actinomycetemcomitans-negative students showed bone loss (P = 0.01). A. actinomycetemcomitans serotype did not appear to influence survival. These findings suggest that detection of A. actinomycetemcomitans in periodontally healthy children can serve as a risk marker for initiation of LAP.  相似文献   
15.
A 14 year old boy is presented who was admitted to the psychiatric ward because of delirium. He also had gynaecomastia, facial oedema, striae, and hypertension. He was finally proved to have a mixed oestrogen and cortisol producing adrenal tumour which was removed surgically with complete improvement and no relapse.  相似文献   
16.
17.
One of the factors involved in accelerated atherosclerosis in hemodialysis patients is dyslipidemia. In this study we considered factors involved in intensification of dyslipidemia in hemodialysis patients. This study was done on 36 maintenance hemodialysis patients. Serum lipoprotein (a), Triglyceride, Cholesterol, HDL-C,LDL-C and also serum Intact parathormone(iPTH), Calcium, Phosphorus, Magnesium were measured. In statistical analysis there was not any correlation between serum lipids and iPTH. There was not correlation between serum calcium with serum lipids (p > 0.05). There was not correlation between CaxP product with serum lipids (p > 0.05). There was a positive correlation between serum Magnesium and Lipoprotein(a) (P < 0.05) and also positive correlation between serum magnesium with triglyceride level (P < 0.05) was seen too. Magnesium doesn't increase the lipoprotein synthesis. It may involve in the regulation of some enzymes responsible for lipoprotein synthesis. Correlation of serum magnesium with serum triglycerides can be due to changes in hepatic triglyceride metabolism. Lipoprotein(a) is a non traditional factor of premature atherosclerosis, its association with serum magnesium needs more attention in hemodialysis patients.  相似文献   
18.
A survey in 1996 of our female patients suggest that the three commonest causes of infertility were endometriosis, anovulation and idiopathic which comprises of about 70% of all the patients. In the male patients, sperm morphology evaluation by critical criteria showed that abnormal morphology was present in 71% while 87% of all the semen analysis were abnormal. The objective of this study was to assess the status of IUI before proceeding to formulate patient protocols for IVF in a tertiary infertility referral unit. A retrospective study of patients data was done from Jan 1995 to Dec 1996. Ovarian stimulation by clomiphene for anovulatory and idiopathic patients was performed on couples with at least one patent fallopian tube. Ovulation induction was by an intramuscular injection of 5000 i.u of HCG after follicular maturation. IUI was performed approximately 36-40 hours later. A total of 74 couples received 114 treatment cycles producing a total of 9 conceptions. The conception rate of IUI was therefore 7.89% per cycle and 12.16% per couple with the cumulative pregnancy rate of 28.21%. Associated success features of IUI found in this study were the age of the woman and the semen parameters of the husband.  相似文献   
19.
In this work, the changes in expression of the adhesion molecules ICAM-1/LFA-1 on inflammatory cells of the liver were studied by immunohistochemistry. Mice sensitized with SEA and infected with S. mansoni and S. mansoni-infected controls were examined from day 35 to day 56 postinfection. A significant upregulation of ICAM-1 and LFA-1 in both the SEA group and the infected control group started shortly after egg deposition at day 35 and persisted up to day 56 p.i. Notably, both ICAM-1 and LFA-1 expression peaks were shifted earlier to day 38 p.i. in the SEA group compared to day 40 in the infected control group. The distribution of ICAM-1 and LFA-1 in both groups was comparable. At the early phase of infection before granuloma formation, both ICAM-1 and LFA-1 were detected along the sinusoidal wall of small blood vessels. At the acute cellular granuloma phase, they were homogeneously distributed all over the inflammatory cells, while at the chronic fibrocellular stage a non-homogeneous staining of granuloma cells at the periphery of the granuloma was apparent. The present data suggest that adhesion molecules play a role in the initiation and maintenance of granuloma formation. Thus, the granulomatous hyporesponsiveness induced by sensitization with SEA was associated with reduced expression of adhesion molecules.  相似文献   
20.

Ethnopharmacological relevance

Since Thymus caramanicus Jalas is used as a folk medicine for the treatment of rheumatism, skin disorders, bacterial infections and diabetes and it contain antioxidant agents, we decided to investigate the possible effects of Thymus caramanicus Jalas (TCJ) extract on in vitro and in vivo models of diabetic neuropathy.

Materials and methods

The high glucose-induced cell injury in Pheochromocytoma (PC12) cells and streptozotocin-induced diabetic rats were used. Tail-flick and rotarod treadmill assessments were used to determine nociceptive threshold and motor coordination. Cell viability was determined by MTT assay test. Western blotting was performed to measurement of apoptosis markers.

Results

The data showed that elevation of glucose consecutively increases functional cell injury and apoptosis. Furthermore, diabetic rats developed thermal hyperalgesia and motor deficit. Activated caspase 3, cytochrome c release and Bax/Bcl-2 ratio were significantly increased in high glucose-treated PC12 cells and in spinal cord of diabetic animals. TCJ extract (60 and 80 µg/ml) attenuates high glucose-induced PC12 cells damage and apoptosis. In diabetic animals, TCJ extract at daily doses of 100 and 150 mg/kg ameliorated hyperalgesia and suppressed spinal apoptosis.

Conclusion

The data indicate that TCJ extract has neuroprotective effects against high glucose-induced neural damage. These protective effects are mediated, at least in part, through attenuation of neural apoptosis and suggest therapeutic potential of TCJ extract in amelioration of diabetic neuropathy.  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