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排序方式: 共有121条查询结果,搜索用时 31 毫秒
61.
Tanya Ali Haj-Hassan Matthew J Thompson Richard T Mayon-White Nelly Ninis Anthony Harnden Lindsay FP Smith Rafael Perera David C Mant 《The British journal of general practice》2011,61(584):e97-e104
Background
Symptoms are part of the initial evaluation of children with acute illness, and are often used to help identify those who may have serious infections. Meningococcal disease is a rapidly progressive infection that needs to be recognised early among children presenting to primary care.Aim
To determine the diagnostic value of presenting symptoms in primary care for meningococcal disease.Design of study
Data on a series of presenting symptoms were collected using a parental symptoms checklist at point of care for children presenting to a GP with acute infection. Symptom frequencies were compared with existing data on the pre-hospital features of 345 children with meningococcal disease.Setting
UK primary care.Method
The study recruited a total of 1212 children aged under 16 years presenting to their GP with an acute illness, of whom 924 had an acute self-limiting infection, including 407 who were reported by parents to be febrile. Symptom frequencies were compared with those reported by parents of 345 children with meningococcal disease. Main outcome measures were diagnostic characteristics of individual symptoms for meningococcal disease.Results
Five symptoms have clinically useful positive likelihood ratios (LR+) for meningococcal disease: confusion (LR+ = 24.2, 95% confidence interval [CI] = 11.5 to 51.3), leg pain (LR+ = 7.6, 95% CI = 4.9 to 11.9), photophobia (LR+ = 6.5, 95% CI = 3.8 to 11.0), rash (LR+ = 5.5, 95% CI = 4.3 to 7.1), and neck pain/stiffness (LR+ = 5.3, 95% CI = 3.5 to 8.3). Cold hands and feet had limited diagnostic value (LR+ = 2.3, 95% CI = 1.9 to 3.0), while headache (LR+ = 1.0, 95% CI = 0.8 to 1.3), and pale colour (LR+ = 0.3, 95% CI = 0.2 to 0.5) did not discriminate meningococcal disease in children.Conclusion
This study confirms the diagnostic value of classic ‘red flag’ symptoms of neck stiffness, rash, and photophobia, but also suggests that the presence of confusion or leg pain in a child with an unexplained acute febrile illness should also usually prompt a face-to-face assessment to exclude meningococcal disease. Telephone triage systems and primary care clinicians should consider these as ‘red flags’ for serious infection. 相似文献62.
Purpose: The purpose of the present study was to determine whether contact lens wear disturbed the levels of tear proteins and to further determine whether this was a transient or continuous disruption. Methods: Lactoferrin, lysozyme and albumin were quanti-tated from tears of neophyte patients and were compared with the levels of these proteins in contact lens wearers after one and six nights and 6 months of extended wear The quantitation of these tear proteins was performed by sandwich ELISA and turbidimetric assay. Results: Results showed that there were no statistically significant changes in the concentration of any of the proteins investigated. Conclusions: Extended wear of hydrogel lenses does not appear to alter the concentration of the major tear film proteins, indicating that the tear film is constantly replenished to maintain protein levels, which are depleted due to protein adsorption to the lens surface. 相似文献
63.
Polycyclic aromatic hydrocarbon-DNA adducts in human placenta and modulation by CYP1A1 induction and genotype 总被引:6,自引:1,他引:5
Whyatt RM; Bell DA; Jedrychowski W; Santella RM; Garte SJ; Cosma G; Manchester DK; Young TL; Cooper TB; Ottman R; Perera FP 《Carcinogenesis》1998,19(8):1389-1392
This study investigated the relationship in human placenta between
polycyclic aromatic hydrocabon (PAH)-DNA adduct levels and two biomarkers
of cytochrome P4501A1 (CYP1A1): gene induction evidenced by CYP1A1 mRNA,
and a genetic polymorphism, the CYP1A1 MspI RFLP. CYP1A1 codes for an
inducible enzyme system that catalyzes the bioactivation of PAHs. Prior
research found a high correlation in human lung tissue between CYP1A1
activity and DNA damage from PAHs. The CYP1A1 Mspi RFLP has been linked in
some studies to risk of lung cancer. The relationships in human placenta
between DNA damage, CYP1A1 activity and genotype have not been well
characterized and may be relevant to risks from transplacental PAH
exposure. The study cohort consisted of 70 newborns from Krakow, Poland, a
city with elevated air pollution, and 90 newborns from nearby Limanowa, an
area with lower air pollution but greater indoor coal use. Contrary to
results seen previously in lung tissue, CYP1A1 mRNA was not significantly
correlated with PAH-DNA adduct levels in the placenta. Smoking
(self-reported maternal and infant plasma cotinine) was significantly
associated with CYP1A1 mRNA levels (P < 0.01), but not with PAH-DNA
adduct levels. Placental PAH- DNA adduct levels were significantly higher
in infants with the CYP1A1 MspI restriction site compared with infants
without the restriction site (P < 0.01), implicating a genetic factor in
inter-individual variation in DNA damage in human placenta. Further studies
are needed to determine the relevance of this finding to risk of
transplacental carcinogenesis.
相似文献
64.
65.
The benefits of hormone replacement therapy (HRT) in non-diabetic postmenopausal women are now well established. HRT improves climacteric symptoms and has beneficial effects on the cardiovascular system and the skeleton. In addition, recent studies suggest a reduced risk of Alzheimer's disease and colorectal cancer. Despite these beneficial effects, concerns continue regarding the increased risk of malignancy, thromboembolism and the possible deterioration in blood pressure. There are no long-term studies in women with diabetes who also receive HRT, so we cannot be certain of the benefits and risks in this population. We can postulate, however, and draw some conclusions from current data, which suggest that the risk/benefit ratio is similar to that for the non-diabetic population. Based on present information, postmenopausal diabetic women should be actively considered for HRT provided the physician is aware of the possible problems and the patient is sufficiently counselled to make an informed decision. 相似文献
66.
67.
68.
Hamartomas of the lung often present as asymptomatic, noncharacteristic masses that can seldom be differentiated from other lung masses such as primary cancer or metastases by conventional radiography. Transthoracic needle-aspiration biopsy (TNAB) has become a popular and reliable method for the diagnosis of a lung lesion, and it offers a valuable alternative to diagnostic thoracotomy. In our study, TNAB established the diagnosis of pulmonary hamartoma in 12 of 14 (86%) patients. In eight patients, one procedure (using one to three punctures) was sufficient to establish the diagnosis, and, in four patients, two procedures (using one to two punctures) were necessary. In two patients, the lesion was missed on second and/or third biopsy procedures, and the correct diagnosis was obtained at surgery. Cytologic examination of the material was diagnostic in five of the 14 patients. Tissue specimens were sent in 13/14 patients, and findings of histologic examination established the correct diagnosis in 11 of these patients. One of the 12 patients in whom hamartoma was correctly diagnosed by TNAB underwent resection of his lesion, and histologic examination confirmed the diagnosis. In the remaining 11 patients, the lesions have been stable on follow-up chest examinations. 相似文献
69.
70.
Aromatic DNA adducts in foundry workers in relation to exposure, life style and CYP1A1 and glutathione transferase M1 genotype 总被引:3,自引:2,他引:3
Hemminki K; Dickey C; Karlsson S; Bell D; Hsu Y; Tsai WY; Mooney LA; Savela K; Perera FP 《Carcinogenesis》1997,18(2):345-350
Levels of aromatic DNA adducts in foundry workers and controls were
followed at four annual samplings. During this time exposure to polycyclic
aromatic hydrocarbons (PAH) decreased and the level of DNA adducts
decreased accordingly. In the total group exposure was related to the level
of adducts. Adduct levels correlated with urinary 1- hydroxypyrene
(LOGU1OH), air benzo[a]pyrene, weekly working hours and daily cigarette
consumption. In a multivariate model 1-hydroxypyrene had a consistent
effect. Neither glutathione transferase M1 (GSTM1) nor cytochrome P450 1A1
(CYP1A1) genotypes had clear effects. Yet the individuals lacking GSTM1 had
a stronger effect of LOGU1OH and some effect by other sources of PAH, such
as charcoal broiled food, although all these variables were not significant
in the multivariate model. The rare individuals with a CYP1A1 polymorphism
MspI containing an amino acid change at isoleucine had an increased level
of adducts. The results showed that the postlabelling method used was able
to detect an increase in aromatic DNA adducts in leukocytes when exposure
to benzo[a]pyrene in air was approximately 5 ng/m3. At such low levels
smoking and charcoal broiled food may be important contributors to adducts.
相似文献