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191.
192.

Objective

This work aimed for detection of different congenital and acquired abnormalities affecting the pulmonary veins using multislice computed tomography (MSCT).

Patients and methods

This study was carried on 74 patients. Cases were referred to Radiology department of Kasr Al-Ainy with different chest complaints for MSCT and only cases showing pulmonary venous abnormalities were included in this study. All patients underwent MSCT of the chest using different MSCT protocols according to the initial presentation of the patient.

Results

This study included 74 patients with pulmonary veins abnormalities; congenital anomalies of the pulmonary veins were observed in 36.4% of cases and acquired abnormalities in 62.2% of cases, one case had both congenital and acquired pulmonary vein abnormalities (1.4%). The most common congenital anomaly was pulmonary vein varices while the most common acquired abnormality was pulmonary vein stenosis or obstruction.

Conclusion

The presence of different pulmonary venous abnormalities can be easily delineated using MSCT, with its MPR capability, as it provides excellent resolution and a large field of view.  相似文献   
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We aimed to compare the effects of new treatment modalities to conventional hormone replacement therapy (HRT) on left ventricular (LV) diastolic function, by means of conventional and tissue Doppler echocardiography and the myocardial integrated backscatter (IBS) in postmenopausal women. One hundred and fifty healthy postmenopausal women were included in this study. Subjects were assigned to one of the five groups receiving 1 year of treatment (estrogen, estrogen plus progesterone, raloxifene, tibolone or placebo). E and A wave velocity, E/A ratio, isovolumic relaxation time (IVRT), deceleration time (DT), peak early (Em) diastolic mitral annular velocity, E/Em ratio, the cyclic variation of integrated backscatter (CVIBS) and the mean value of the IBS signal (MIBS) were determined before and 12 months after therapy. E (76 ± 10 vs. 98 ± 8 cm/s, P = 0.0001 and 78 ± 10 vs. 90 ± 12 cm/s, P = 0.02, respectively), Em (14.3 ± 2.4 vs. 16.4 ± 2.5 cm/s, P = 0.001 and 15.1 ± 3.4 vs. 16.2 ± 3.5 cm/s, P = 0.01, respectively), and E/A ratio (1.15 ± 0.3 vs. 1.42 ± 0.4, P = 0.0001 and 1.0 ± 0.2 vs. 1.22 ± 0.2, P = 0.01, respectively) were increased significantly compared to pretreatment in both estrogen and raloxifene groups while DT, A, E/Em, and IVRT were significantly decreased. A significant increase in CVIBS and decrease in MIBS were detected 12 months after estrogen and raloxifene administration while no significant changes were observed in other groups. Changes in the MIBS and CVIBS were found to be independently associated with the observed changes in the diastolic function indexes during therapy. Both estrogen and raloxifene regimens may improve LV diastolic functions in healthy postmenopausal women. This improvement may be a result of direct cardiac effects on LV myocardium.  相似文献   
195.
Helicobacter pylori infection causes chronic gastritis that may progress to peptic ulcers or gastric adenocarcinoma and thereby cause major world-wide health problems. Previous studies have shown that CD4+ T cells are important in the immune response to H. pylori in humans, but the role of CD8+ T cells is less clear. In order to study the CD8+ T cell response to H. pylori in greater detail, we have evaluated efficient conditions for activation of CD8+ T cells in vitro. We show that H. pylori-reactive CD8+ T cells can be activated most efficiently by B cells or dendritic cells pulsed with H. pylori antigens. We further show that the majority of CD8+ T cells in H. pylori-infected gastric mucosa are memory cells, and that memory CD8+ T cells sorted from peripheral blood of H. pylori-infected individuals respond 15-fold more to H. pylori urease compared to memory cells from uninfected subjects. We conclude that CD8+ T cells do participate in the immune response to H. pylori, and this may have implications for the development of more severe disease outcomes in H. pylori-infected subjects.  相似文献   
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Familial Mediterranean Fever (FMF) is an autosomal recessive disease that is widely spread in the populations of the Mediterranean region. It is characterized by recurrent fever and inflammatory attacks. A total of 1700 suspected patients, belonging to various communities in Israel: Jews (Ashkenazi and non-Ashkenazi), Arabs (Muslims and Christians) and Druze, was subjected to examination for FMF mutation screening. The patients were screened for the most common six MEFV gene mutations namely, M680I, M694V, M694I, V726A, E148Q and K695R. Fifty-five percent of the cases were confirmed to have MEFV mutations. The most common mutations among all the cases studied were M694V, E148Q and V726A. The common mutations in the respective communities were: among the Jews M694V with a frequency of 69.9% (76.8% for non-Ashkenazi Jews and 43.6% for Ashkenazi Jews), among the Arabs V726A with a frequency of 32.7% (32.7% for Muslims and 32.1% for Christians) and among Druze it was E148Q with a frequency of 52.1%. The characteristic mutation present in Jews was K695R and the one in Arabs was M680I, while no characteristic mutation was found in Druze. On the other hand, mutation E148Q was observed to have a considerable occurrence in patients of all ethnic groups studied. Furthermore, our results revealed that homozygous mutations accounted for 168 cases (18%). The homozygote mutation M694V was the most prevalent among Jews and the E148Q mutation was the most common among Druze, while, among Arabs there were three homozygous mutations having maximum prevalence, namely, V726A, M694V and M694I. Our study comprehensively provided a spectrum of FMF mutations in various communities of Israeli society.  相似文献   
198.
PROBLEM: The presence of interleukin-18 (IL-18) in serum and pre-ovulatory follicular fluid (FF) and its possible correlation to in-vitro fertilization/embryo transfer (IVF/ET) outcome and ovarian hyperstimulation syndrome (OHSS) development. METHOD OF STUDY: A prospective study was carried out. Assays for serum and pooled pre-ovulatory FF levels of IL-18 were performed on 30 patients who underwent oocyte retrieval for IVF/ET. RESULTS: Mean serum and FF levels of IL-18 were 370.4 +/- 224 and 228.9 +/- 208 pg/mL, respectively (r = 0.77, P < 0.0001). Levels of FF IL-18 were comparable between the two ovaries (right = 221 +/- 166.8 pg/mL, left = 237 +/- 171.9 pg/mL; r = 0.7550, P = 0.49). A positive correlation was found between IL-18 FF levels and number of retrieved oocytes (r = 0.45; P = 0.019). In three patients (10%) who developed OHSS, the mean serum level of IL-18 at day of ovum pickup was significantly higher compared with patients without OHSS (620 +/- 196 pg/mL versus 345 +/- 251 pg/mL, respectively, P = 0.04). CONCLUSIONS: Both pre-ovulatory FF and serum levels of IL-18 correlate with the number of retrieved oocytes. The serum IL-18 level at day of ovum pickup may predict consequent development of OHSS. Further investigations are warranted to determine the role of IL-18 in the folliculogenesis and OHSS pathogenesis.  相似文献   
199.
In this paper, the hemodynamics in a three-dimensional out-of-plane sequential bypass graft model is first investigated. Based on the advantageous flow characteristics observed within the side-to-side (STS) anastomosis in the sequential bypass graft simulation, a new CABG coupled-sequential anastomosis configuration is designed, entailing coupled STS and end-to-side (ETS) anastomotic components. In this new CABG design, the flow fields and distributions of various wall shear stress parameters within the STS and ETS anastomotic regions are studied, and compared to those of the conventional distal anastomosis, by means of computational fluid dynamics simulation of pulsatile Newtonian blood flow. Simulation results demonstrate that the new sequential anastomoses model provides: (i) a more uniform and smooth flow at the ETS anastomosis, without any stagnation point on the artery bed and vortex formation in the heel region of the ETS anastomosis within the coronary artery; (ii) a spare route for the blood flow to the coronary artery, to avoid re-operation in case of re-stenosis in either of the anastomoses; and (iii) improved distribution of hemodynamic parameters at the coronary artery bed and in the heel region of the ETS anastomosis, with more moderate shear stress indices. These advantages of the new design over the conventional ETS anastomosis are influenced by the occlusion ratio of the native coronary artery, and are most prominent when the proximal segment of the coronary artery is fully occluded. By varying the design parameters of the anastomotic angle and distance between the two anastomoses, the superior coupled STS–ETS anastomoses design is found to have the anastomotic angle of 30° and 30 mm distance between the two (STS and ETS) components.  相似文献   
200.
PROBLEM: Recently, it has been suggested that anticardiolipin antibodies (ACAs) may serve as possible markers for reproductive failure. The association between ACAs and embryo morphology in patients undergoing in vitro fertilization (IVF) was investigated. METHOD OF STUDY: This prospective study comprised 117 patients with either tubal factor or unexplained infertility. Embryo morphology was blindly scored from I to IV according to blastomere regularity and the presence of fragments. Anticardiolipin antibodies (immunoglobulin [Ig] G and IgM) were detected. RESULTS: Anticardiolipin antibodies were found in 26 (50%) of the 52 patients with abnormal morphology, compared with 13 (20%) of the 65 patients with normal embryo morphology (P = 0.001). No statistically significant differences were found between the prevalence of ACAs among patients with tubal factor and those with unexplained infertility (29.6% and 36.5%, respectively). CONCLUSIONS: Our study shows an association between embryo morphology and the presence of ACAs. This association may explain the low implantation rate and early pregnancy loss in patients with ACAs.  相似文献   
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