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1.
Coiled bodies and interfascicular threads are conspicuous white matter abnormalities of brains of patients with progressive supranuclear palsy (PSP). Both structures are argyrophilic and immunoreactive for the microtubule-binding protein tau. This report concerns the ultrastructural localization of interfascicular threads and their relationship to coiled bodies in five PSP patients. We showed for the first time that abnormal tubules with a 13- to 15-nm diameter and fuzzy outer contours were the common structures of coiled bodies in the oligodendroglial perikarya and of interfascicular threads. Moreover, the tubules were immunolabeled by anti-tau antibodies. The abnormal tau-positive tubules of interfascicular threads were located in the inner loop of the myelin sheath. Our study further indicated that the thread-like structures in the white matter comprised, at least in part, oligodendroglial processes, and that they were also present in gray matter. We consider that the formation of coiled bodies in the perikarya and of interfascicular threads represents a common cytoskeletal abnormality of the oligodendroglia of PSP patients. Moreover, even though the white matter alterations of PSP resemble those of corticobasal degeneration, there are certain ultrastructural differences in the abnormal oligodendroglial tubules of the two diseases. Received: 4 October 1996 / Accepted: 6 December 1996  相似文献   
2.
A technique for estimation of the longitudinal relaxation time of a large homogeneous object with an acquisition time of 4 s or less was developed by combining spatially selective rf tagging pulses with a T1-weighted magnetization-prepared gradient-echo sequence. Multiple 5-mm-wide tagged areas are laid orthogonal to the imaging section of interest. The contrast between each tag and the untagged regions differs because each tag is produced at a different time. The T1 value is determined from the nulling time at which tagged and untagged areas have no contrast.  相似文献   
3.
It is very important to observe the concentrations and flow patterns of blood through a dialyzer to evaluate its function and to obtain the most appropriate design. We established a visualization method for the blood flow pattern in a dialyzer using X-ray computed tomography, and investigated the so-called internal filtration phenomenon. The results obtained were as follows: (1) The influence of 5% BaSO4, which was added to the blood as a contrast medium, on the filtration rate of the dialyzer was minimal. (2) The relationship between the concentration of BaSO4 and the Hounsfield unit value was expressed by linear regression. (3) Hounsfield unit values increased massively just after blood entered the dialyzer and peak values increased with dialysate perfusion under the following conditions: the dialyzer (BS-1.6UL, polysulfone hollow fibers) was used, and bovine blood with 5% BaSO4 added was used at a blood flow rate of 200ml/min. The dialysate flow rate was 500ml/min and the slice thickness of X-ray computed tomography was 1–10mm. (4) It was observed that blood flowed slightly faster in the center than the peripheral portion of the dialyzer, when the flow pattern was followed after pulse injection of blood containing 20% BaSO4 into the dialyzer. It was concluded that this method could possibly be utilized not only qualitatively but also quantitatively for observation of the real state of blood flow and in designing dialyzers.  相似文献   
4.
It is well known that physical exercise can reduce coronary risk factors. But how an aerobic exercise modifies coronary risk factors in relation to severity and physical fitness is still controversial. Fifty-four middle-aged women (mean age, 55 years) completed a 6-month on-site and home-based anaerobic threshold-level exercise program. The changes in coronary risk factor profiles were observed during the pre-intervention and intervention periods. Before the intervention (during control period), most coronary risk factors showed a rather unfavorable trend. After the program, their mean body weight decreased from 56.7 to 55.7 kg (p>0.05) and the proportion of body fat from 30.9 to 27.9% (p>0.05) without any reduction in lean body mass. Systolic blood pressure (SBP) decreased from 129.0 to 125.0 mm Hg (p>0.05) and diastolic blood pressure from 79.5 to 76.6 mm Hg (p>0.05). Fasting plasma glucose (FPG) declined from 109.6 to 103.4 mg/dl (p>0.05). Changes in SBP and FPG were most remarkable in their respective worst tertile. Serum lipids improved only modestly. Maximum oxygen uptake increased from 23.6 to 26.1 ml/kg/min (p>0.01). However, no significant correlations were found between changes in coronary risk factors and those in physical fitness. We conclude that the 6-month aerobic exercise program would modify women’s coronary risk factors depending on their initial values, probably independently of the changes in physical fitness.  相似文献   
5.
Mycotic aneurysms of the subclavian artery are rare. This report describes an experience of 2 rare cases in which transcatheter embolization with metallic coils was performed for the management of these lesions alternative to surgery. Two patients who had been treated with chemotherapy for malignant neoplasms were diagnosed as having mycotic aneurysms of the left subclavian artery. The causes of these lesions were presumed to be the invasion of the arterial wall by the pulmonary abscess in case 1, and wound infection after placement of the reservoir for intraarterial chemotherapy in case 2. In both cases, proximal and distal sites of the aneurysm were embolized with metallic coils. In case 1, the vertebral artery was also embolized with Guglielmi detachable coils to avoid retrograde blood flow. Both aneurysms were completely occluded by a single embolization. In case 1, although weakness and paresthesia of the left hand remained, lethal hemoptysis due to aneurysmal fistulization to the lung parenchyma ceased. In case 2, no neurological deficit except for mild paresthesia in the left thumb had been observed. Both patients died of primary disease 10 and 5 months after the procedure. Transcatheter embolization is technically feasible and effective enough to treat the mycotic aneurysm of the subclavian artery even in the situation in which the surgical option seems to be difficult or risky.  相似文献   
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Using helical computed tomography (CT), we evaluated cystic pancreatic lesions in 11 patients and compared the imaging and the histopathologic findings. Helical CT allowed us to assess the tumor vasculature. Contrastenhanced images showed satisfactory details of the cysts, cyst walls, and intracystic structures. Helical CT is extremely useful for the evaluation of cystic pancreatic lesions.  相似文献   
9.
The first, definition of pulmonary tuberculosis bacilli with multiple drug resistance was decided as "bacilli completely resistant to RFP 50 mcg + SM 20 mcg and/or INH 1 mcg + KM 100 mcg and/or EB 5 mcg and/or another antituberculosis drug" based on 118 cases examined for drug resistance pre-operatively in 35 institutions belonging to the Tuberculosis Research Committee, during the 6 years period 1984 to 1989. Next, 48 pulmonary tuberculous cases with multiple drug resistance were analysed, and the following conclusions were obtained: 1) Pulmonary tuberculosis cases with multiple drug resistance were 36% of 133 cases of positive tuberculosis bacilli before operation. 2) 52% were more than 50 years old. One third showed less than 40 in respiratory index. 3) Most of them did not have effective anti-tuberculosis drug to be used after operation. 4) There was a high rate of pneumonectomy and collapse therapy such as thoracoplasty. 5) Successful rate of treatment was 72.9%, which is rather good for multiple drug resistant tuberculous cases. But bacilli positive rate after operation and mortality were 12.5% and severe complications such as bronchial or pulmonary fistula, thoracic empyema and worsening of tuberculosis after operation was 25%. Therefore surgical treatment for pulmonary tuberculosis with multiple drug resistance needed careful application considering sensitive drug to be used after testing of resistance for all anti-tuberculosis drugs. Surgical treatment should be considered especially if pulmonary tuberculosis cases have complete resistance to RFP and to one drug among SM, INH, KM and EB.  相似文献   
10.
Objectives: We sought to determine the effects of experience on the Mitraclip® procedure steps as well as procedure safety and functional results. Background: MR has proven deleterious in heart failure. Mitraclip® therapy evolved an important option in patients with severely reduced left ventricular function (LVEF). Methods: Between 2011 and 2016, 126 consecutive patients were grouped in three groups and investigated in a prospective observational study. We evaluated the duration of procedural steps, safety endpoints, and functional results. Results: The median logistic EuroScore was 32% (7–40%). Ninety‐five percent of patients were in NYHA‐stage ≥III and 51% had a LVEF <30%. Groups were homogeneous as to their baseline NYHA status and right heart catheterization data. Echocardiography data are comparable, albeit with a decreasing effective regurgitant orifice area (0.44 ± 0.21 group I vs. 0.34 ± 0.22 group III, P = 0.02). Frailty was less frequent and baseline 6 min walking test results improved from group I to group III. Duration of a first clip placement decreased from 106 ± 50 to 50 ± 21 min (P < 0.001). Total procedure time decreased from 221 ± 70 to 144 ± 68 (P < 0.001). The number of clips implanted increased from 66 to 79 (P = 0.02). MitraClip® implantation was effective in either group but the combined safety endpoint was reached less frequent in group III (P = 0.01). There was no difference in MACCE rate, 30 day‐ or intrahospital‐mortality between groups. Conclusion: Safety and duration of procedure steps improved substantially with experience. MR reduction was sustained from the beginning without further improvement. Patient selection is a key factor for success. © 2016 Wiley Periodicals, Inc.  相似文献   
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