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91.
OBJECTIVE: To investigate the combined influence on respiratory health of smoking and exposure in an aluminium potroom. METHODS: In a cross sectional study of 75 potroom workers (23 never smokers, 38 current smokers, 14 ex-smokers) and 56 controls in the same plant (watchmen, craftsmen, office workers, laboratory employees; 18 non-smokers, 21 current smokers, 17 ex-smokers), prevalences of respiratory symptoms and spirometric indices were compared. RESULTS: Smokers in the potroom group had a lower prevalence of respiratory symptoms than never smokers or ex-smokers, which was significant for wheezing (2.6% v 17.4% and 28.6% respectively, both p < 0.01), whereas respiratory symptoms in controls tended to be highest in smokers (NS). No effects of potroom work on the prevalence of respiratory symptoms could be detected. In potroom workers, impairment of lung function due to occupational exposure was found only in non-smokers, with lower results for forced vital capacity (FVC) (98.8% predicted), forced expiratory volume in one second (FEV1) (96.1% predicted) and peak expiratory flow (PEF) (80.2% predicted) compared with controls (114.2, 109.9, and 105.9% predicted; each p < 0.001). Conversely, effects of smoking on lung function were only detectable in non-exposed controls (current smokers v non-smokers: FVC 98.8% v 114.2% predicted; p < 0.01; FEV1 95.5 v 109.9% predicted; p < 0.05). CONCLUSIONS: In a cross sectional survey such as this, the effects of both smoking and occupational exposure on respiratory health may be masked in subjects with both risk factors. This is probably due to strong selection processes which result in least susceptible subjects continuing to smoke and working in an atmosphere with respiratory irritants.

 

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92.
93.
Objective: The aim of this cross-sectional study was to investigate possible acute and long-term respiratory health effects of work at different working places in the primary aluminum industry. Method: A cross-sectional study was carried out on 78 potroom workers, 24 foundry workers, and 45 carbon-plant workers (n = 147, exposed group), and 56 control workers (watchmen, craftsmen, office workers, laboratory employees) of a modern German prebake aluminum plant. The survey consisted of pre- and postshift spirometric and urinary fluoride measurements. Results: Potroom workers had significantly lower preshift results with regard to forced vital capacity (FVC, 99.5% versus the 107.2% predicted; P < 0.05) and peak expiratory flow (PEF, 85.2% versus the 98.4% predicted; P < 0.01) as compared with controls. In a multiple regression model a small but significant negative correlation was found between postshift urinary fluoride concentrations and FVC, FEV1, and PEF. Across-shift spirometric changes were observed only in FVC among carbon-plant workers (103.0 ± 13.3% predicted preshift value versus 101.2 ± 13.6% predicted postshift value; P < 0.05). Conclusions: The results suggest that lung function impairment in the modern primary aluminum industry may be only partly due to fluoride exposure and that working in aluminum carbon plants may cause acute lung function changes. Received: 8 July 1998 / Accepted: 31 October 1998  相似文献   
94.
Two cases of familial form (in brothers) of extensive, symmetric, idiopathic calcifications of the basal ganglia and cerebellum (Fahr syndrome) are described. In discussion of factors predisposing to appearance of such idiopathic calcifications, particular attention was given to meningoencephalitis suffered in childhood and coexistence of a tumour of the sella of prolactinoma type, in case 1. Attention was also called to progressive, copious clinical and radiological symptology of the discussed cases. It was impossible to suggest a probable type of inheritance (parents of the patients were dead).  相似文献   
95.
Changes in the content and composition of lipids in brain tumours of different degree of malignancy are still the subject of numerous scientific studies. It is known that in developing brain tumours structural and functional changes of its cells, take place, in which lipids play a crucial role. The examination of the lipid spectrum was conducted in a material extracted from tumour adjacent areas (by means of fenestration) as well as from tumours themselves in 11 patients (mean age 56.8 yrs). Based on histological studies all the tumours were qualified as glioblastoma 4th degree of malignancy. Lipids were isolated from the tumours as well as from their adjacent areas. Later on they were separated, using column chromatography and thin-layer chromatography, into three classes: phospholipids, galactolipids and neutral lipids. Separated lipids were subjected to quantitative analysis by spectrophotocolorimetric method. In comparison to adjacent areas, in tumours distinct changes of lipid levels were noticed in all analysed lipid classes. Statistical analysis showed significant decrease of phospholipids (elements stabilizing cell membranes) in tumours in comparison to their adjacent areas (Wilcoxon's test: p < 0.05). At the same time in tumours an increase of level of plasmalogens took place: phosphatidylcholine (PC) (PPC), phosphatidylethanolamine (PE) (PPE) typical elements of malignant tumours, responsible for cross cell membrane transportation processes. This phenomenon was accompanied by changes of levels of PC/PE and PC/SM (sphingomyelin) ratios connected with adhesiveness and other membrane features. Changes in the level of lipids, and phospholipids in particular, in glioblastoma 4th degree of malignancy in comparison to adjacent areas can indicate the pathological processes in cells of these tumours.  相似文献   
96.
Infections by hepatotropic viruses belong to the most common complications of chemotherapy in children suffering from neoplastic diseases. The rate of hepatitis B virus (HBV) or hepatitis C virus (HCV) infection and the effectiveness of passive immunization against HBV were studied in 285 children; 148/285 with lymphoproliferative diseases and 137/285 with solid tumours. HBV infection was observed in 10.2% children receiving hepatitis B immune globulin as compared to 36.8% without passive immunization against HBV. Anti-HCV antibodies were similar in both groups amounting 38.7% and 32.6% respectively. Conclusion The results show that hepatitis B immune globulin administration is effective and that HCV might become the main cause of hepatitis among immunosuppressed patients in the future. Received: 13 December 1994 / Accepted: 18 October 1996  相似文献   
97.
The influence of reported paternal attitudes on the decision to breast-feed   总被引:1,自引:0,他引:1  
Objective: To identify factors that influence a woman's decision to breast-feed.
Methodology: Five hundred and fifty-six women were recruited from the maternity wards of two Perth hospitals. Data were collected from a self-administered questionnaire completed by participants prior to discharge. Logistic regression analysis was used to determine factors influencing the initiation of breast-feeding.
Results: At discharge from hospital 83.8% of women were breast-feeding, including 6% who were giving complementary formula feeds. After controlling for potentially confounding demographic and biomedical factors, the father's reported preference for breast-feeding was found to be the most important factor influencing a woman's decision to breast-feed (OR 10.18).
Conclusion: Fathers participate in and influence the choice of infant feeding method and should be included in breast-feeding discussions.  相似文献   
98.
OBJECTIVE: Most neonatologists include an apnea-free period in the criteria for the discharge of preterm infants. However, the length of time one should wait after the cessation of apnea before sending an infant home without a monitor is debated. We undertook this study in an attempt to define a minimal and safe observation period between the time of the last apnea episode and discharge. METHODS: We reasoned that in infants with idiopathic apnea of prematurity, the intervals between days on which apnea occurs gradually increase until some point at which clinically significant apnea ceases. Therefore, knowledge about the intervals between days on which apnea occurred just before the last apnea would provide a reasonable estimate of the minimal safe observation interval between the last apnea and discharge. We reviewed the charts of 266 infants born in 1993 and 1994 at 相似文献   
99.
100.
The present study investigated the effects of dietary oltipraz on cigarette smoke-related lipophilic DNA adduct formation. Female Sprague- Dawley rats were exposed daily to sidestream cigarette smoke in a whole- body exposure chamber 6 h/day for 4 consecutive weeks. One group of rats was maintained on control diet while another group received the same diet supplemented with either a low (167 p.p.m.) or high (500 p.p.m.) dose of oltipraz, starting 1 week prior to initiation of smoke exposure until the end of the experiment. Analysis of lipophilic DNA adducts by the nuclease P1-mediated 32P-post-labeling showed up to five smoke-related adducts. Adduct no. 5 predominated in both the lung and the heart while adduct nos 3 and 2 predominated in the trachea and bladder, respectively. Quantitative analysis revealed that the total adduct level was the highest in lungs (270+/-68 adducts/10(10) nucleotides), followed by trachea (196+/-48 adducts/10(10) nucleotides), heart (141+/-22 adducts/10(10) nucleotides) and bladder (85+/-16 adducts/10(10) nucleotides). High dose oltipraz treatment reduced the adduct levels in lungs and bladder by >60%, while the reduction in lungs in the low-dose group was approximately 35%. In trachea, the effect of low and high dietary oltipraz on smoke DNA adduction was equivocal, while smoke-related DNA adducts in the heart were minimally inhibited by high-dose oltipraz. In a repeat experiment that employed a 3-fold lower dose of cigarette smoke, oltipraz (500 p.p.m.) was found to inhibit the formation of DNA adducts in rat lungs and trachea by 80 and 65%, respectively. These data clearly demonstrate a high efficacy of oltipraz in inhibiting the formation of cigarette smoke-induced DNA adducts in the target tissues.   相似文献   
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