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91.
Solitary pulmonary nodules: CT assessment   总被引:29,自引:0,他引:29  
Computed tomography (CT) was used to examine 634 solitary pulmonary nodules (SPNs). Each lesion was assessed as benign or indeterminate on the basis of CT criteria. Benign nodules made up 44% of all SPNs and 58% of the 431 that were 2 cm or less in diameter. All malignant SPNs were assessed as indeterminate, and adenocarcinoma (42%) was the most common primary malignancy. A total of 176 (63% of benign SPNs) were correctly assessed as benign by CT. Ninety SPNs assessed as diffusely calcified were not so identified by conventional tomography at outside institutions. An SPN can be reliably assessed by CT as benign if it exhibits high attenuation values, exceeding a critical level and distributed diffusely throughout a CT section through the center of the lesion and a well-defined edge. Although 38 of 283 (13.4%) primary lung cancers contained localized calcification, there was no significant overlap with the diffuse calcification of benign lesions. Central carcinoid tumors may contain focal ossification, but such lesions may be recognized by noting the proximity of larger bronchi. Assessment of SPNs by CT is most effective for lesions 2.0 cm or less in diameter. For larger lesions, the frequency of benign disease was decreased (14.3% of 203), as was the percentage of benign SPNs correctly assessed as benign by CT (37.9%).  相似文献   
92.
Harris  GR; Stewart  HF; Leo  FP; Sanders  RC 《Radiology》1989,173(2):313-317
Ultrasonographic B-mode images were obtained at various exposure levels with three real-time diagnostic scanners. Adult human and tissue-equivalent phantom images were compared in terms of diagnostic content and depth of penetration. For the exposure level settings used, spatial-peak pulse-average intensities ranged from approximately 10 to 500 W/cm2. At the 3.50-3.75-MHz nominal frequencies used in the study, images of the human abdomen showed little discernible change in quality with varying exposure levels. However, phantom tests confirmed that depth of penetration is a function of exposure level. The results suggest that a judicious use of exposure level and receiver gain controls can be a practical means for minimizing patient exposure to ultrasound without sacrifice of diagnostic effectiveness.  相似文献   
93.
Sullivan  JL; Woda  BA; Herrod  HG; Koh  G; Rivara  FP; Mulder  C 《Blood》1985,65(5):1097-1104
The virus-associated hemophagocytic syndrome (VAHS) is a disorder characterized by a benign, generalized histiocytic proliferation, with marked hemophagocytosis associated with systemic viral infections. We have studied the virological and immunopathological events occurring in two children experiencing Epstein-Barr VAHS. Neither of the patients had an underlying immunodeficiency and both recovered from their disease and are completely well one year after follow-up. In each patient, evidence for primary Epstein-Barr virus (EBV) infection was documented with a typical humoral immune response, including IgM antibody directed against virus capsid antigen. EBV was demonstrated in lymphoreticular tissues by electron microscopy and molecular hybridization studies. Permissive EBV infection was suggested by the finding of mature virus particles and linear viral DNA in lymphoreticular tissues. Immunopathological studies demonstrated complete effacement of lymph node architecture by a marked proliferation of immunoblasts in patient 1 and infiltration and effacement of the lymph node architecture with benign-appearing histiocytes in patient 2. Atypical lymphocytes characteristic of acute EBV infection were notably absent in the peripheral blood of both patients and cytotoxic T cells, which normally lyse EBV-infected B cells, were also absent from the peripheral circulation. Our observations suggest that EBV-induced VAHS may be the result of an increased virus burden in the face of immunoregulatory cell imbalances.  相似文献   
94.
95.
    
Pancreatic ductal adenocarcinoma is an aggressive cancer with high recurrence rates following surgical resection.While adjuvant chemotherapy improves survival,a significant proportion of patients are unable to initiate or complete all intended therapy following pancreatectomy due to postoperative complications or poor performance status.The administration of chemotherapy prior to surgical resection is an alternative strategy that ensures its early and near universal delivery as well as improves margin-negative resection rates and potentially improves long-term survival outcomes.Neoadjuvant therapy is increasingly being recommended to patients with pancreatic ductal adenocarcinoma,however,patient-centered research on its use is lacking.In this review,we highlight opportunities to focus research efforts in the domains of patient preferences,patient-reported outcomes,patient experience,and survivorship.Novel research in these areas may identify relevant barriers and facilitators to the use of neoadjuvant therapy thereby increasing its utilization,improve shareddecision making for patients and providers,and optimize the experience of those undergoing neoadjuvant therapy.  相似文献   
96.
97.
Fifty-six Thai males and 146 Thai females aged 60 years and above visiting a special clinic for the elderly were investigated. The serum protein and immunoglobulin of these elderly were assessed. Anthropometric measurements were also taken. From a random sample of the group, the dietary intake of main nutrients was determined by a 24 h recall method with the help of food models. Weight, height and mid-arm muscle circumference of males were greater than those of females. Triceps skinfold thickness was less in the males than in the females. Forty-seven per cent of the individuals investigated had 1-antitrypsin levels below 200 mg/dl and 25.4% had IgG levels of 200 mg/dl and 39% IgA levels above 450 mg/dl. The males tend to consume more calories in the form of carbohydrates than the females. The nutritional density of fat was less than 20% in the males. A negative correlation between serum albumin and height and a positive correlation between serum IgG and tricep skinfold thickness were found. Weight was found to have a positive correlation with calories, carbohydrates and fat. Height correlated positively with calories, protein and carbohydrates. Serum prealbumin correlated with fat intake. It is concluded that, except for 1-antitrypsin, IgA, serum proteins are found in a range normally detected also in elderlies in western countries. Body composition does not relate to level of protein intake.  相似文献   
98.
Adolescence is the age of crises, changes, adaptation to the new body and new attitudes towards life. If we add to this the meaning of pregnancy from personal, social and family points of view, we will understand how difficult it can be for the adolescents. The purpose of this study was to identify where the pregnant teenagers look for support. Results showed that they had family support, mainly from parents, and less frequently from the baby's father. It also showed the pregnancy acceptance, its relation to school abandonment, the girls' idealized vision of pregnancy and future expectations, the concern about biological aspects and the lack of concern about real problems.  相似文献   
99.
An intervention project focusing on the health of women in the reproductive age was conducted in three districts of Khon Kaen Province, northeast Thailand between 1991 and 1996. Main emphasis was placed on improving reproductive health, the nutritional status including the iron deficiency anemia (IDA) as well as iodine deficiency disorders (IDD), and the parasitic diseases liver fluke (Opisthorchis viverrini) and hookworm. For implementation a community based Primary Health Care approach was used including the training of health officials in health matters, primary health care workers and villagers as well as enhancing health education and the dissemination of health information. The health delivery system was encouraged to take appropriate actions such as in the treatment of parasitic diseases and the control of IDA and IDD. Monitoring was done on a regular basis. The outcome of the project was assessed by comparing baseline data compiled from a random sample of the target population with the results of the final evaluation. An attempt to compare results obtained from villages within and outside of the project area failed most probably because of spill over effects. A number of important indicators on family planning and mother and child health care improved during the time the project was implemented; this included practising family planning, and participation in antenatal care. Also the proportion of females becoming pregnant for the first time when 20 years or older increased. Child-raising also improved in that almost all females gave colostrum to their babies by this time. Almost 75% of the women breast-fed their children. Improvements occurred in the nutritional status as far as the micronutrients iron and iodine were concerned, however the overall nutritional status of females did not change, but a rather high proportion of females were found to be overnourished. The project failed in reducing abortion and the proportion of females becoming pregnant when they are 18 years old or younger. It was also not possible to improve the usage of postnatal care. As anticipated, the results achieved so far are most suitable in serving as a training ground and providing a favorable example to improve family planning, mother- and child health care, and also the general health of females in the region, particularly in neighboring countries such as Lao PDR, Cambodia and Vietnam.  相似文献   
100.
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