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181.
Strokes have been rarely associated with immunoglobulin G (IVIg) therapy. A 70-year-old woman with stable polycythemia vera developed Guillain-Barré syndrome and received IVIg, 8 days following which she became comatose due to bilaterally symmetric cerebral infarcts. Autopsy showed intravascular aggregates of fibrin-IgG but also platelets and a necrotizing microangiopathy in the infarcts.  相似文献   
182.
Talkha power plant is the only power plant located in El-Mansoura. It generates electricity using two different methods by steam turbine and gas turbine. Both plants drew water from River Nile (208 m3 /h). The Nile raw water passes through different treatment processes to be suitable for drinking and operational uses. At Talkha power plant, there are two purification plants used for drinking water supply (100 m3/h) and for water demineralization supply (108 m3/h). This study aimed at studying the efficiency of the water purification plants. For drinking water purification plant, the annual River Nile water characterized by slightly alkaline pH (7.4-8), high annual mean values of turbidity (10.06 NTU), Standard Plate Count (SPC) (313.3 CFU/1 ml), total coliform (2717/100 ml), fecal coliform (0-2400/100 ml), and total algae (3 x 10(4) org/I). The dominant group of algae all over the study period was green algae. The blue green algae was abundant in Summer and Autumn seasons. The pH range, and the annual mean values of turbidity, TDS, total hardness, sulfates, chlorides, nitrates, nitrites, fluoride, and residual chlorine for purified water were in compliance with Egyptian drinking water standards. All the SPC recorded values with an annual mean value of 10.13 CFU/1 ml indicated that chlorine dose and contact time were not enough to kill the bacteria. However, they were in compliance with Egyptian decree (should not exceed 50 CFU/1 ml). Although the removal efficiency of the plant for total coliform and blue green algae was high (98.5% and 99.2%, respectively), the limits of the obtained results with an annual mean values of 40/100 ml and 15.6 org/l were not in compliance with the Egyptian decree (should be free from total coliform, fecal coliform and blue green algae). For water demineralization treatment plant, the raw water was characterized by slightly alkaline pH. The annual mean values of conductivity, turbidity, and TDS were 354.6 microS/cm, 10.84 NTU, and 214.6 mg/I, respectively. There was an increase in the results of conductivity, turbidity, total hardness, and TDS in carbon filter effluent which was attributed to the desorption of adsorbed ions on the carbon media. The removal efficiencies of turbidity, total hardness, and TDS indicated the high efficiency of the cationic filter. The annual removal efficiencies of conductivity, turbidity, chloride, and TDS proved the efficiency of the anionic filter for removing the dissolved and suspended ions. All of the recorded values of the pH, conductivity, turbidity, chlorides, hardness, and TDS of the mixed bed effluent indicated that the water at this stage was of high quality for boiler feed. The study recommended adjustment of coagulant and residual chlorine doses as well as contact time, and continuous monitoring and maintenance of the different units.  相似文献   
183.

Background  

The role of the crural diaphragm during increased intra-abdominal pressure is not exactly known. We investigated the hypothesis that the crural diaphragm undergoes reflex phasic contraction on elevation of the intra-abdominal pressure with a resulting increase of the lower esophageal pressure and prevention of gastro-esophageal reflux.  相似文献   
184.
BACKGROUND: The rectum exhibits electric activity in the form of slow waves or pacesetter potentials (PPs) and action potentials (APs), which are suggested to be initiated from a rectosigmoid pacemaker (RSP). We hypothesized that the RSP and electric waves are responsible for rectal motility. This hypothesis was investigated. METHODS: The rectum of 13 mongrel dogs was exposed through an abdominal incision, and 3 electrodes were fixed serially to the rectal serosa. The rectal pressure was measured by a 6 F saline-perfused catheter and the rectal electromechanical response to rectal balloon distension in increments of 5 ml of air was registered. The test was repeated after rectosigmoid junction (RSJ) anesthetization by 20 minutes and 3 hours using xylocaine injection. It was done also after saline instead of xylocaine injection. RESULTS: PPs and APs were recorded and had the same frequency, amplitude and conduction velocity from the 3 electrodes of the same animal. APs occurred randomly and were coupled with elevated rectal pressure. Rectal balloon distension produced increase of the rectal electric activity and pressure, which increased with the increase of the rectal distension until, at a mean volume of 31.2 +/- 5.4 ml, the balloon was expelled to the exterior. RSJ anesthetization abolished the rectal electric waves and effected no balloon expulsion with high volume rectal distension. The rectal waves appeared after waning of the anesthetic effect. Saline injection into the RSJ produced no significant effect on the rectal electromechanical activity. CONCLUSION: Rectal electric waves are suggested to be initiated from the RSP and to be responsible for the rectal motor activity. Incremental rectal balloon distension effected progressive increase of the rectal electromechanical activity until the balloon was expelled to the exterior RSJ anesthetization blocked the electric waves and the electromechanical response to rectal distension. These results have probably clinical significance when performing electrorectograms for various rectal pathologic conditions as well as when applying an artificial pacemaker to the non-contractile rectum.  相似文献   
185.
OBJECTIVE: Muscle forces are not directly measurable without invasive methods (i.e., tendon force transducers). Techniques such as dynamic electromyography are therefore required to obtain insight into the role of muscles during motion. There is controversy about the choice of recording electrode type. Surface electrodes are noninvasive and allow recording over a large area yet may allow intramuscular crosstalk. Indwelling electrodes also have been used in gait analysis. This electrode type is able to analyze the electrical activity of small or deep muscles. Despite the advantages of intramuscular electrodes for some applications, this electrode type is often rejected because of the need for skin penetration and for specialized personnel to acquire the data. The reliability of the wire electromyographic signal has also been questioned. The objective of this study was to determine if there were differences in the test-retest reliability of surface vs. intramuscular electrodes in gait analysis. DESIGN: Surface and intramuscular electromyographic data were obtained from the soleus muscle in 18 adults with no history of neuromuscular disease as they performed self-selected speed walking. A statistical criterion (variance ratio) was used to measure the reproduction of phasic patterns of muscle activity with both wire and surface electrodes on repeat-day testing of the soleus muscle. RESULTS: Each electrode type was remarkably consistent. Mean variance ratio values for wire electrodes (mean = 187) were slightly lower than mean surface electromyographic variance ratio values (mean = 199). These differences did not approach statistical significance (P = 0.768). CONCLUSIONS: The study results show that the dynamic electromyographic signal obtained with wire electrodes is, at minimum, as repeatable as surface electromyograms.  相似文献   
186.
BACKGROUND: How afferent activity in the gut achieves the required ingestion control has not been established. The authors hypothesized that gastric overdistension effects an increase in pharyngo-esophageal and lower esophageal sphincter activity aimed at inhibiting ingestion. MATERIAL/METHODS: The study comprised 16 mongrel dogs. Under anesthesia, one balloon-tipped catheter was placed in the stomach, another within the lower esophageal sphincter (LES), and a third within the pharyngo-esophageal sphincter (PES). The gastric balloon was filled with H(2)O in increments of 10 ml and LES and PES pressures were recorded. The test was repeated after individual gastric, LES, and PES anesthetization. RESULTS: Gastric balloon filling with more than 20 ml of H(2)O showed progressively increasing LES pressure up to 110-120 ml of gastric filling, beyond which the pressure exhibited no further increase upon incrementally increased gastric filling volume. PES pressure increased only with a gastric filling volume exceeding 100-110 ml and continued to increase with increasing gastric filling. Gastric filling as above while the stomach, LES, and PES were separately anesthetized produced no LES or PES pressure response. CONCLUSIONS: LES and PES appear to contract on gastric filling; PES responds only to excess gastric filling. It seems that LES and PES response to gastric filling is mediated through a reflex which the authors call the "gastro-esophagopharyngeal reflex" (GEPR). Changes in the evoked response would indicate a defect in the reflex pathway. GEPR might thus serve as an investigative tool in the diagnosis of gastroesophageal disorders, although further studies are required.  相似文献   
187.
Early detection of hepatocellular carcinoma (HCC) is crucial for successful therapy. The present work examined the value of ultrastructural morphometric image analysis of hepatocyte nuclei in patients with chronic hepatitis C virus (HCV) versus HCC cases with chronic HCV and the corresponding surgical tumor-free safe margins (TFMs), to highlight any early predictive signs of neoplastic cellular transformation. This work also performed an immunohistochemical assessment of cytokeratin 19 (CK19) and Ki-67-positive cells to visualize any associated proliferative activity in the examined groups.

The results showed significant decrease in the hepatocyte nuclear surface areas in the HCC and TFMs versus those in the HCV cases. The hepatocyte nucleolar surface area was significantly increased in the HCC cases versus that in the HCV cases. This increase was associated with a significant increase in Ki-67-positive cells in the HCC cases compared to those in the other groups. Conversely, the mean number of CK 19-positive cells was significantly reduced in the HCC cases compared to the cell numbers in TFMs and HCV cases with severe hepatic fibrosis. Liver progenitor cells (LPCs) were discerned in the reactive ductules and canaliculo-ductular junctions that characterized TFMs. LPCs were sporadically distributed in the liver lobules and reactive bile ductules in the HCC samples.

In conclusion, CK 19 represents an important marker for distinguishing between dysplastic and malignant liver nodules. Electron microscopic morphometric image analysis may be considered as adjunct factor for assessing hepatocyte malignant transformation. Wider scale studies are needed to authenticate these results.  相似文献   

188.
To identify the most active curative treatment of Buruli ulcer, two regimens incorporating the use of rifampin (RIF) were compared with the use of RIF alone in a mouse footpad model of Mycobacterium ulcerans infection. Treatments began after footpad swelling from infection and continued for 12 weeks with five doses weekly of one of the following regimens: (i) 10 mg of RIF/kg alone; (ii) 10 mg of RIF/kg and 100 mg of amikacin (AMK)/kg; and (iii) 10 mg of RIF/kg, 100 mg of clarithromycin (CLR)/kg, and 50 mg of sparfloxacin (SPX)/kg. The activity of each regimen was assessed in terms of the reduction of the average lesion index and acid-fast bacillus (AFB) and CFU counts. All three regimens displayed various degrees of bactericidal activity against M. ulcerans. The ranking of bactericidal activity was found to be as follows: RIF-AMK > RIF-CLR-SPX > RIF. RIF-AMK was able to cure M. ulcerans-infected mice and prevent relapse 26 weeks after completion of treatment. To determine the impact of different rhythms of administration of RIF-AMK on the suppression of M.ulcerans growth, mice were given the RIF-AMK combination for 4 weeks but doses were administered either 5 days a week or twice or once weekly. After completion of treatment, the mice were kept under supervision for 30 additional weeks. M. ulcerans was considered to have grown in the footpad if swelling was visually observed and harvests contained more than 5 x 10(5) AFB per footpad. The proportion of mice in which growth of M. ulcerans occurred, irrespective of drug dosage, was compared with the control mice to determine the proportion of M. ulcerans killed. Each dosage of RIF-AMK was bactericidal for M. ulcerans (P < 0.001), but the effect was significantly stronger in mice treated 5 days per week. The promising results of RIF-AMK treatment in M. ulcerans-infected mice support the clinical trial that is currently in progress under World Health Organization auspices in Ghana.  相似文献   
189.
Background/aim We investigated the hypothesis that external (EUS) and internal (IUS) urethral sphincters and urinary bladder (UB) respond to penile thrusting (PT) of vagina in a way that prevents urinary leakage during coitus. Methods Vaginal condom was inflated with air in increments of 50–300 ml and EMG of EUS and IUS and vaginal pressure were recorded; test was repeated after anesthetization of vagina, UB, EUS, and IUS. Results Vaginal distension effected reduction of vesical pressure but increase of IUS EMG until the 150 ml distension was reached, beyond which more vaginal distension caused no further effect; EUS EMG showed no response. Vaginal distension while vagina, UB, EUS, and IUS had been separately anesthetized, produced no change. Conclusion Vaginal balloon distension appears to effect vesical relaxation and increased IUS tone. This seems to provide a mechanism to avoid urine leakage during coitus and to occur through a reflex we term ‘vagino-urethrovesical reflex’.  相似文献   
190.
ObjectiveTo examine the sociodemographic and clinical characteristics of psychiatric patients with recurrent psychiatric readmissions (RPR).MethodsA retrospective study was conducted at Hamad General Hospital in Qatar on psychiatric patients with recurrent readmissions from August 2018 to January 2019.ResultsOf 380 psychiatric patients admitted during the study period, 40 (10.5%) were readmitted within 30 days of discharge. Most of the patients who were readmitted were single, male and unemployed. Psychotic spectrum disorder was the most frequent psychiatric condition and was diagnosed in 18 (45%) patients. A total of 30% of the patients were receiving treatment with anti-psychotics, and a similar number received more than one medication. Most patients showed poor or no compliance. Only 12.5% of patients stayed in the hospital for more than 5 weeks in their last admission during the study period.ConclusionsPoor compliance, male sex and single status were the most common demographic and clinical features of patients with RPR. Post-discharge psychiatric care should be tailored to meet the requirements of patients prone to RPR.  相似文献   
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