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51.
Amniotic fluid alkaline ribonuclease (RNase) activity was measured in 55 normal and 29 neural tube defect pregnancies. The pregnancies which resulted in neural tube defects gave a mean value of 2,500 U/l with a SD of 600 compared with a mean activity of 1,600 U/l (SD 350) from the control normal pregnancies. The mean amniotic fluid RNase activity of 15 anencephalic pregnancies was 2,600 U/l (SD 600), compared with 1,600 U/l (SD 350), for 28 gestational age-matched controls. Highest RNase activities appear to be related to anencephaly.  相似文献   
52.
Serum alkaline phosphatase isoenzyme patterns have been obtained using starch gel electrophoresis. The intestinal isoenzyme was detected in about one-third of over 300 serum samples examined. The incidence was high in cirrhosis and chronic renal failure but low in gastrointestinal disease. In serum from some patients the intestinal isoenzyme was the only isoenzyme present. Isoenzymes of unusual electrophoretic mobility were found in the serum of eight patients.  相似文献   
53.
The presence of excess aluminium was investigated in 204 samples of iliac bone from 197 patients with chronic renal failure by using the aluminon and solochrome azurine staining techniques. The results were compared with values obtained by atomic absorption spectrophotometry (AAS). Overall, the staining reactions correlated with the AAS data, but the solochrome azurine stain was positive more often than was the aluminon stain (in 90.6% and 62.3%, respectively, of bone samples with greater than the control group mean +3SD (that is, in the range 17.8 to 113.4 micrograms aluminium/g Solochrome azurine staining was consistently positive in all cases, with greater than 23.1 micrograms aluminium/g bone but the corresponding aluminon stain was occasionally inexplicably negative in this range. In some samples solochrome azurine was positive in parts of old unresorbed cement lines when the aluminon stain was negative and the bone aluminium concentration was within the normal range or slightly increased. The stains, particularly solochrome azurine, have the advantage over AAS in that they indicate the location as well as the presence of excess bone aluminium.  相似文献   
54.
Superficial- and deep-tissue heating was measured in five dogs during high-specific-absorption-rate radiofrequency (RF) irradiation to see whether significant temperature changes could be produced by a 1.5-T clinical magnetic resonance imager. The RF power output employed was 6.3 times that required for routine imaging. Temperature probes were placed in both deep and superficial tissues, and temperatures were recorded before, during, and after exposure. In each dog, there was a linear temperature increase of several degrees during RF exposure; the maximal average change was 4.6 degrees C in the urinary bladder. The temperature increase was slightly greater in deep tissues than in superficial tissues. The calculated specific absorption rate, based on the temperature change, averaged 7.9 W/kg for all five dogs. These findings argue for continued caution in the design and operation of imagers capable of high specific absorption rates, particularly when they are used for imaging infants or patients with altered thermoregulatory capability.  相似文献   
55.
Measurement of alpha-fetoprotein concentration and acetylcholinesterase activity in amniotic fluid can be used to identify chromosomal defects as well as neural tube defects. In seven cases of trisomy 21 and one case of partial trisomy 3, alpha-fetoprotein concentrations were below the reference range but values for acetylcholinesterase activity were normal for the appropriate gestational age. One case of trisomy 13 had an increase in acetylcholinesterase activity and normal alpha-fetoprotein concentration.  相似文献   
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Guanosine 3':5'-phosphate (cycle GMP) in urine has been used to monitor the response of patients with ovarian cancer to treatment. Changes in the cyclic GMP level appear to correlate well with clinical status in that the disappearance of clinically detectable tumour is associated with a drop in the level whereas a tumour recurrence is associated with an elevation. Serially measured cyclic GMP is valuable for detecting a recurrence of tumour growth in patients in clinical remission and can predate any clinical signs by as much as 10 months. In patients who show no response to treatment, cyclic GMP levels in urine are elevated in the majority of specimens collected.  相似文献   
59.
Hamburger  AW 《Blood》1980,56(4):633-639
Recent studies have shown that soluble factors elaborated by human T lymphocytes enhance erythroid burst formation by human peripheral blood null cells. This study demonstrates that media conditioned by a long- term T lymphocyte line augmented the growth of erythroid colonies in vitro in the presence of erythropoietin (Ep). ATCC.CCl 119 (CCRF-CEM) was derived from a patient with ALL of T-lymphoblast origin. Cells from the stocks used in these experiments maintained T-cell characteristics as determined by histochemical and rosetting techniques. Increased numbers of 16 day BFU-E were seen when Ficoll-Hypaque separated peripheral blood leukocytes were cultured in the presence of a 10% (v/v) concentration of CCL 119 conditioned medium (CM). CM increased the number of BFU-E even when Ep or fetal calf serum were not growth limiting. CM also increased the number of late BFU-E observed in cultures of nonadherent bone marrow cells. When peripheral blood mononuclear cells were depleted of E-rosetting cells, only small numbers of BFU-E grew. Addition of 119 CM increased the numbers of BFU- E in E-rosette-depleted cultures. CM from B-cell, macrophage, or other T-cell lines tested did not stimulate BFU-E growth as consistently. These studies indicate that CM obtained from ATCC.CCL 119 cells contained burst-promoting activity, one of the factors required for proliferation of early erythroid progenitors.  相似文献   
60.
Background and objectives:   Few longitudinal studies have examined the risk factors and natural history of adult-onset asthma. This study assessed the subject characteristics and lifestyle factors that predicted the new diagnosis of asthma in adulthood and how these factors changed over time in those who developed asthma compared with those who do not.
Methods:   The study enrolled 1554 adults from the Busselton Health Study seen in 1981 and again in 1994–1995 who initially reported never having had doctor-diagnosed asthma. Questionnaire measures were used to assess doctor-diagnosed asthma, respiratory history and tobacco smoking. Height, weight and spirometric measures of lung function were measured. Atopy was assessed by skin prick tests. Logistic regression analysis was used to identify risk factors for adult-onset asthma and changes over time.
Results:   Reported wheeze, rhinitis, chronic cough, smoking and lower levels of lung function in 1981 each predicted asthma diagnosis by 1994–1995. Neither initial skin-prick reactivity nor newly positive skin-prick tests at follow up were associated with adult-onset asthma. Those diagnosed with asthma were more likely to have new wheeze, new rhinitis, new habitual snoring, weight gain and excess decline in lung function.
Conclusions:   Adult-onset asthma has risk factors that are distinct from those observed in childhood asthma. The presence of upper airway symptoms including rhinitis, as well as lifestyle factors, such as smoking, predicts those at greatest risk. However, neither pre-existing atopy nor new atopy as measured by skin prick tests was associated with adult-onset asthma.  相似文献   
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