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71.
ABSTRACT: The activity of a 100–110-Kd immunosuppressive fraction (ISF), isolated from boar seminal plasma, was investigated in mice. In vitro, this fraction was found to inhibit a unidirectional mixed lymphocyte response and cell-mediated lymphocytotoxicity, as well as antisheep red blood cells (T-dependent) and antitrinitrophenylated lipopolysaccharide (T-independent) responses. The ISF also inhibited the macrophage phagocytosis of erythrocytes coated with IgG antibodies, but it did not suppress the natural killer activity. In vivo, ISF was found to lower both the primary responses to T-dependent and to T-independent antigens. Trypsin or pronase digestion of ISF provided active molecules of 30 Kd or 2–5 Kd respectively, thus showing that the activity is due to a protein. This ISF factor, capable of suppressing a wide variety of immune functions and remaining active after cleavage by proteases, could play a role in the lack of immune response against the spermatozoa present in the sow genital tract after intercourse. The use of this factor as a therapeutic agent in humans could eventually be considered after further molecular characterization.  相似文献   
72.
The aim of the study was to investigate the value of the Mini-Mental State Examination (MMSE) for use by general practitioners (GPs) in a group of elderly patients in whom the GPs are considering a dementia diagnosis. The study population consisted of 533 elderly patients (aged 65 and older) judged by 36 GPs as suffering from ‘minimal to severe’ dementia. Cross-sectional data were used to determine the criterion validity of separate items, a set of items and the total MMSE. The GMS/AGECAT diagnosis was used as an external criterion. MMSE items were analysed and two items testing general knowledge were added. The most effective set of items was determined using a stepwise logistic regression analysis. Adjusted for age, sex and education, the differentiating ability of the set of items was compared to that of the total MMSE score. The total MMSE score was divided into three categories (cutoffs 21/22 and 26/27) and into two categories (cutoff 23/24). In total, 114 patients (21%) were diagnosed as having an ‘organic syndrome’ by the GMS/AGECAT. The differentiating ability of separate items was poor. The following combination of items had the best predictive ability: items concerning the date, the day of the week, the patient's address and the current prime minister. This set of items was just as adequate in differentiating dementia from non-dementia as the total MMSE score (sensitivity 64.9% and 64.8% respectively, specificity 96.4% and 93.3%). The value of the MMSE in diagnosing dementia in general practice is limited. The score on cognitive test items can be one aspect of the individual's overall clinical picture, on which the diagnosis should be based. © 1997 by John Wiley & Sons, Ltd.  相似文献   
73.
The aim of the study was to define criteria for left ventricular pacing in dilated cardiomyopathy (DCM) using an echocardiographic evaluation of interventricular electromechanical delay (IMD) and a correlation of IMD to QRS duration. Standard 12-lead ECG and echocardiography with pulsed Doppler tissue imaging (DTI) were recorded in 35 DCM patients (mean age 58 +/- 11 years) with QRS duration from narrow (80 ms) to broad (222 ms) patterns. The timefor left ventricular activation was evaluated from the onset of QRS to the onset of aortic flow (Q-Ao) by standard pulsed Doppler (SP) or to the onset of mitral annulus systolic wave (Q-Mit) (DTI). The time for right ventricular activation was determinedfrom the onset of QRS to the onset of pulmonary flow (Q-Pulm) (SP) or to the onset of tricuspid annulus systolic wave (Q-Tri) (DTI). (Q-Ao)-(Q-Pulm) and (Q-Mit)-(Q-Tri) determined IMD for each method, respectively. QRS width and IMD showed correlation coefficients of r = 0.86 ([Q-Ao]-[Q-Pulm]) and r = 0.82 ([Q-Mit]-[Q-Tri]) (P < or = 0.001 ). Mean IMD of 77 +/- 15 ms (SP) and 88 +/- 26 ms (DTI) were noted for QRS width above 150 ms. Left ventricle delayed activation was positively correlated to QRS widening with both methods, (r = 0.90, [Q-Ao]), (r = 0.83, [Q-Mit]) (P < or = 0.001). In conclusion, QRS duration is a good marker of an interventricular mechanical asynchrony. According to IMD correction, left ventricular pacing may be mainly proposed to symptomatic DCM patients with QRS duration > 150 ms.  相似文献   
74.
Angiographic Anatomy of the Coronary Sinus and Its Tributaries   总被引:15,自引:1,他引:15  
Permanent left ventricular pacing has been shown to imporve the hemodynamic and clinical status of patients with severe heart failure. To pace the left ventricle, the electrode is implanted in tributaries of the coronary sinus (CS). However, the anatomy of cardiac veins with this purpose in mind has not been described in detail. Methods: One hundred consecutive patients admitted for coronary angiography had a simultaneous coronary venography performed after the injection of 8 to 10 mL of contrast material into the left coronary artery. Cardiac veins were analyzed in antero-posterior, left anterior oblique 60±, and right anterior oblique 30± views by three different observers. The number, dimension, angulation, and position of the coronary sinus and of its tributaries were studied. Results: Two veins are consistently present: the middle cardiac vein (mean diameter 2.62 ± 1.26 mm) and the great cardiac vein (mean diameter 3.55 ± 1.24 mm). The left posterior vein(s) (LPV) (mean diameter 2.25 ± 1.2 mm) is (are) variable in number (ranging from 0 to 3), size, and angulation. The absence of LPV limits the ability to pace the left ventricle endovenously. The diameter of the vein (< 2 mm) and its angulation may also complicate the insertion of the lead. Conclusion: Angiographic analysis of dimensions, tortuosity, number, and angulation of venous tributaries of the CS seems to allow the insertion of commercially available pacing leads in approximately 85% of cases. An increase in this percentage hinges on the development of new, dedicated leads.  相似文献   
75.
76.
Van EIjk J Th M (Department of Family Medicine, University ofNijmegen, St Annastraat 284, 6525 HC Nijmegen, The Netherlands).Serious illness and family dynamics. 1. Changes in consultingpatterns of the unafflicted family members. Family Practice1985; 2: 61–69. This article examines the effect of an acute serious illnessin one member of a family on the health behaviour of other members.The number of consultations made by 92 family members beforeand after an acute serious illness was measured and comparedwith a control group of 102 people who had experienced no seriousillness in their family. The coping resources of the family—definedin terms of flexibility of parental relationships, conflictavoidance and family strain—were assessed and relatedto the changes in consultation pattern. It was shown that an acute serious illness affecting one memberof a family which lacks adequate coping resources can lead toan increase in reporting of serious complaints in other familymembers. In families which have adequate coping resources, however,the health of the remaining family members can apparently improve.This refutes the view that a serious life event necessarilyhas only a harmful influence on health.  相似文献   
77.
This study analyzed the results of 3,701 patients implanted with cardiac pacemakers at the Centre Chirurgical du Val d'Or between 1976 and 1981. Two pacemaker populations were compared; those having a new pacemaker and (hose implanted with a reused pacemaker. There were no statistically significant differences between the two groups, either in terms of indications for implantation or in terms of actuarial survival of patients. In addition, there was no significant change in survival of the pulse generator. The reutilization of pacemakers appeared to be in no way detrimental to patients.  相似文献   
78.
Abstract— Twenty new derivatives of 4-amino-4H-1,2,4-triazole and 5-aminothiazole have been examined for their inhibitory potential towards serine and aspartic proteases. Upon prolonged incubation with enzyme, the phenylacetylaminothiazolium salts exhibit progressive, time-dependent inhibition of chymotrypsin according to a first-order process. The formation of a tetrahedral transition state-like complex by attack of the active-site serine at the C2-position of the pseudobase form of the thiazolium may be responsible for the observed effect. Triazolium salts appeared to be simple competitive inhibitors of this enzyme, effective in the Mm range concentration. Poor inhibitions of trypsin and pepsin were also obtained in the triazolium series. In spite of their structural analogy with β-lactams, the selected derivatives failed to inhibit human leucocyte elastase.  相似文献   
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