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11.
Abstract

The efficacy of sodium nitroprusside in resolving cerebral vasospasm was evaluated with multicisternal injections. Twelve animals received fresh, unheparinized arterial blood via three injections (15 ml total) into the cisterna magna. Selective vertebral arteriography was performed on Day 0, and blood injections were performed on the second and third days after the first injection. On the seventh day selective arteriography was performed to evaluate the diameter of the basilar artery. In the sodium nitroprusside group, intrathecal injections of the drug were started on Day 4 and continued for two days (25 μg/kg/day). The diameter of the basilar artery was reduced 72.98 ±11.07% in control experiments. For the animals treated with intrathecal sodium nitroprusside, the mean diameter of the basilar artery was reduced 29.25±4.54%. The . effect of intrathecal sodium nitroprusside on intracranial pressure (ICP), blood pressure (BP) and electrocardiogram (ECO was also evaluated in 14 animals. There were no prominent changes in ICPBP, or ECC when sodium nitroprusside was given intrathecally, but BP decreased and ICP and heart rate increased with intravenous doses of sodium nitroprusside. These results support the hypothesis that sodium nitroprusside administered intrathecally is an effective treatment for cerebral vasospasm. [Neurol Res 1993; 15: 310—315]  相似文献   
12.
Abstract

The resolution of cerebral vasospasm and protection of endothelial damage by lloprost was evaluated with multicisternal injections. Sixteen adult mongrel dogs (18-20 kg) were assigned to one of three experimental groups. All animals received a total amount of 15 ml fresh unheparinized arterial blood via three injections into the cisterna magna. Selective vertebral angiography was performed on day 0 and subsequently blood injections were performed on the 2nd and 3rd days after the first injection. On the 7th day angiography was reperformed to determine the chronic vasospasm. The first group (5 dogs) was the control group and received intrathecal saline which was equal to the amount of saline in which lloprost was diluted. The second group (5 dogs) did not receive any treatment until the 7th day. The third group (6 dogs) received lloprost intrathecally (total 10 fig kg~1). In the first two groups angiographic vasospasm was prominent. For the second group intraarterial lloprost was given on the 7th day in order to evaluate its acute effect. However there was no evidence of resolution of vasospasm. In the third'group, resolution of vasospasm was verified on angiograms. Electron microscope studies of basilar arteries of the first two groups revealed degenerative changes of the endothelial cells which were separated from each other and the elastic lamina was irregularly arranged. In the intrathecal lloprost-treated group there was little thickening in the elastic lamina and the endothelial cells were almost normal in structure. These results can be considered as the evidence of the prophylactic effect of lloprost given by the intrathecal route in the prevention of chronic cerebral vasospasm. [Neurol Res 1995; 17: 301-306]  相似文献   
13.
A case report of doxycycline induced esophageal and gastric ulcer.   总被引:1,自引:0,他引:1  
It is well-established that various drugs can induce esophageal and gastric mucosal injury. Generally neither motility disorder nor an anatomical stricture is found in such cases and the cause of mucosal injury is usually found to be inadequate fluid intake with medicine or consumption just prior to bedtime. Athough there are some case reports of doxycycline induced esophageal mucosal injury, doxycycline induced gastric ulcer has been reported only once in the literature. In this case report, a 33 year old female patient who had been prescribed doxycycline for pelvic inflammatory disease is presented. She was admitted with retrosternal and epigastric pain and odynophagia, which had begun after taking the second oral dose of the drug. Endoscopic examination showed ulcers in the mid esophagus and fundus of the stomach. Histologic findings supported a drug induced etiology in these ulcers. This is only the second case in the literature where gastric ulcer has been caused by doxycycline.  相似文献   
14.
Context: In the present study, cisplatin (CP) induced eye toxicity and the beneficial effect of hesperidin (HP) was investigated.

Methods: Twenty-eight rats were equally divided into four groups; the first group was kept as control. In the second and third group, CP and HP were given at the doses of 7?mg/kg and 50?mg/kg/d, respectively. In the fourth group, CP and HP were given together at the same doses. Tissue samples were collected on day 14 of CP treatment.

Results: The results demonstrated that CP caused a significant increase in thiobarbituric acid reactive substances (TBARS) levels and decrease of glutathione levels and antioxidant enzyme activity (catalase, superoxide dismutase and glutathione peroxidase) in eye tissues compared to other groups, HP prevented these effects of CP. Besides, CP led to histopathological damage in the retina and cornea. On the other hand, HP treatment prevented histopathological effects of CP.

Conclusion: CP had severe dose-limiting toxic effects and HP treatment can be beneficial against the toxic ocular effects of CP. Thus, it appears that co-administration of HP with CP may be a useful approach to attenuate the negative effects of CP on the eye.  相似文献   
15.
Several investigators have estimated the intracranial volume (ICV) in the past which indirectly reflects the brain volume. Most of these studies have been made on the dry skulls using linear dimensions, packing methods or occasionally radiological methods. It is also reported that the etiology of cerebellar tonsillar herniation is closely related to the size of the foramen magnum (FM). In the present study the ICVs have been estimated in 28 dry skulls using filling water method and the surface area of FMs were measured planimetry method. The estimated mean ICV was 1,311 +/- 133 cm. Surface area of FM was 760 +/- 144 mm. Antero-posterior and lateral direct roentgenograms of the skulls were also taken and the width, height and length (WHL) of the skull were measured by means of the cephalometry on radiograms. The relationship between the ICV, WHL and surface area of FM were analyzed statistically. The ICV, WHL and surface area of FM was correlated well (r = 0.271, P < 0.005; r = 0.265, P < 0.005, respectively) and a regression formula was proposed. Our results showed that skulls with larger ICV and WHL have larger FM surface area. We also suggested a regression formula that could be used to predict the surface area of FM regarding to the ICV and WHL values. In the next step, we took roentgenograms of skulls and obtain ICV measuring the width, length and height of skulls by means of cephalometry and investigate the relation between the findings of cephalometry and surface area of FM. The cephalometry could apply on living subjects and, thereby, our findings could provide some data to evaluate the etiology of Arnold Chiari malformation and achondroplasia for living subjects.  相似文献   
16.
17.
The Cavalieri estimator using a point grid is used to estimate the volume of three-dimensional structures based on two-dimensional slices of the object. The size of the components of intracranial neural structures should have proportional relations among them. The volume fraction approach of stereological methods provides information about volumetric relations of the components of structures. The purpose of our study is to estimate the volume and volume fraction data related to the cerebrum, cerebellum and brain stem. In this study, volume of the total brain, cerebrum, cerebellum and brain stem were estimated in 24 young Turkish volunteers (12 males and 12 females) who are free of any neurological symptoms and signs. The volume and volume fraction of the total brain, cerebrum, cerebellum and brain stem were determined on magnetic resonance (MR) images using the point-counting approach of stereological methods. The mean (+/-SD) total brain, cerebrum and cerebellum volumes were 1,202.05 +/- 103.51, 1,143.65 +/- 106.25 cm(3) in males and females, 1,060.0 +/- 94.6, 1,008.9 +/- 104.3 cm(3 )in males and females, 117.75 +/- 10.7, 111.83 +/- 8.0 cm(3) in males and females, respectively. The mean brain stem volumes were 24.3 +/- 2.89, 22.9 +/- 4.49 cm(3) in males and females, respectively. Our results revealed that female subjects have less cerebral, cerebellar and brain stem volumes compared to males, although there was no statistically significant difference between genders (P > 0.05). The volume ratio of the cerebrum to total brain volume (TBV), cerebellum to TBV and brain stem to TBV were 88.16 and 88.13% in males and females, 9.8 and 9.8% in males and females, 2.03 and 2.03% in males and females, respectively. The volume ratio of the cerebellum to cerebrum, brain stem to cerebrum and brain stem to cerebellum were 11.12 and 11.16% in males and females, 2.30 and 2.31% in males and females, 20.7 and 20.6% in males and females, respectively. The difference between the genders was not statistically significant (P > 0.05). Our results revealed that the volumetric composition of the cerebrum, cerebellum and brain stem does not show sexual dimorphism.  相似文献   
18.
Objective: To determine levels of trace elements [copper (Cu), zinc (Zn), selenium (Se), and cobalt (Co)] and heavy metals [arsenic (As), mercury (Hg), lead (Pb), and cadmium (Cd)] in the plasma of mothers and infants and investigate the relationship between those levels and neural tube defects (NTD).

Methods: A total of 100 neonates diagnosed with NTD and placed in the Neonatal Intensive Care Unit of Yuzuncu Yil University, Turkey between May 2013 and December 2016 comprised the study group. The control group consisted of 70 healthy neonates not diagnosed with NTD or any other congenital anomalies. For both the groups, mother and infant plasma levels of Cu, Zn, Co, Cd, Se, Hg, As, and Pb were measured and compared. Plasma levels of Cu, Zn, Co, Cd, Se, Hg, As, and Pb were measured and compared between two groups of mothers and infants.

Findings: Mother and infant plasma levels of trace elements Zn and Se were determined to be significantly lower in the study group compared with the control group, while Cu levels were significant elevated in the study group (all p values p?p?>?.05). Differences in maternal age, birth weight, length of gestation, and infant gender for the two groups were also determined not to be statistically significant.

Results: High plasma levels of heavy metals As, Pb, and Cd and trace element Cu were identified as risk factors for the development of NTD. At the same time, low plasma levels of trace elements Zn and Se were also found to be risk factors for NTD. However, no association between Hg and Co plasma levels and increased risk for the development of NTD was observed. This study, while being the most comprehensive case study to date investigating the relationship between heavy metals and trace element levels and increased risk of NTD, nonetheless highlights the need for further research in order to make definite statements regarding this relationship.  相似文献   
19.
Aim: In the present study, we aimed to assess serum concentrations of zinc (Zn), copper (Cu), iron (Fe), cadmium (Cd), lead (Pb), manganese (Mn), vitamins A (retinol), D (cholecalciferol) and E (α-tocopherol) in patients with coronary artery disease (CAD) and to compare with healthy controls.Methods: A total of 30 CAD patients and 20 healthy subjects were included in this study. Atomic absorption spectrophotometry (UNICAM-929) was used to measure heavy metal and trace element concentrations. Serum α-tocopherol, retinol and cholecalciferol were measured simultaneously by high performance liquid chromatography (HPLC).Results: Demographic and baseline clinical characteristics were not statistically different between the groups. Serum concentrations of retinol (0.3521±0.1319 vs. 0.4313±0.0465 mmol/I, p=0.013), tocopherol (3.8630±1.3117 vs. 6.9124±1.0577 mmol/I, p<0.001), cholecalciferol (0.0209±0.0089 vs. 0.0304±0.0059 mmol/I, p<0.001) and Fe (0.5664±0.2360 vs. 1.0689±0,4452 µg/dI, p<0.001) were significantly lower in CAD patients. In addition, while not statistically significant serum Cu (1.0164±0.2672 vs. 1.1934±0.4164 µg/dI, p=0.073) concentrations were tended to be lower in patients with CAD, whereas serum lead (0.1449±0.0886 vs. 0.1019±0.0644 µg/dI, p=0.069) concentrations tended to be higher.Conclusions: Serum level of trace elements and vitamins may be changed in patients with CAD. In this relatively small study we found that serum levels of retinol, tocopherol, cholecalciferol, iron and copper may be lower whereas serum lead concentrations may be increased in patients with CAD.  相似文献   
20.
Background/aimIt has been suggested that there is a significant progress in coronary artery disease (CAD) by many pathophysiological mechanisms. Nondipper hypertension (NDH) has been shown to have higher target organ damage and have a higher rate of cardiovascular mortality and morbidity. In this study, we investigated the effect of nondipper hypertension on the progression of coronary atherosclerosis.Materials and methodsA total of 186 patients who underwent coronary angiography twice between 6 months and 3 years were included in the study. Coronary angiography was repeated on the admission day due to angina or positive exercise test and the patients were divided into groups.ResultsProgression of coronary artery disease was detected in 58 of 186 patients. Seventy-one of the total patients were found to be nondipper hypertensive. Nondipper hypertension, hypertension, diabetes mellitus, low-density lipoprotein, and total cholesterol were found to be effective in the progression of CAD. Among these parameters, it was seen that nondipper hypertension and hyperlipidemia were the most important independent risk factors.Conclusion Coronary artery disease is a progressive disease, and this progression depends on many reasons. In our study, we showed that nondipper hypertension is a new parameter that is effective in CAD progression.  相似文献   
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