全文获取类型
收费全文 | 319篇 |
免费 | 20篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 32篇 |
基础医学 | 27篇 |
口腔科学 | 6篇 |
临床医学 | 38篇 |
内科学 | 50篇 |
皮肤病学 | 4篇 |
神经病学 | 4篇 |
特种医学 | 132篇 |
外科学 | 8篇 |
综合类 | 6篇 |
预防医学 | 10篇 |
药学 | 19篇 |
1篇 | |
肿瘤学 | 11篇 |
出版年
2021年 | 3篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2018年 | 4篇 |
2017年 | 3篇 |
2016年 | 1篇 |
2015年 | 2篇 |
2013年 | 5篇 |
2012年 | 3篇 |
2011年 | 1篇 |
2010年 | 3篇 |
2009年 | 8篇 |
2008年 | 4篇 |
2007年 | 10篇 |
2006年 | 9篇 |
2005年 | 2篇 |
2004年 | 3篇 |
2003年 | 1篇 |
2002年 | 1篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1999年 | 9篇 |
1998年 | 18篇 |
1997年 | 15篇 |
1996年 | 26篇 |
1995年 | 15篇 |
1994年 | 21篇 |
1993年 | 16篇 |
1992年 | 3篇 |
1991年 | 6篇 |
1990年 | 6篇 |
1989年 | 18篇 |
1988年 | 15篇 |
1987年 | 19篇 |
1986年 | 11篇 |
1985年 | 10篇 |
1984年 | 8篇 |
1983年 | 12篇 |
1982年 | 10篇 |
1981年 | 9篇 |
1980年 | 8篇 |
1979年 | 5篇 |
1978年 | 1篇 |
1977年 | 6篇 |
1976年 | 9篇 |
1975年 | 2篇 |
排序方式: 共有349条查询结果,搜索用时 15 毫秒
181.
DB Bethell TT Hien LT Phi NP Day H Vinh NM Duong NV Len LV Chuong NJ White 《Archives of disease in childhood》1996,74(1):44-46
The aim of the study was to document the effects of short courses of fluoroquinolones given during an outbreak of multidrug resistant typhoid fever in southern Viet Nam on the growth of children over a period of two years. In a prospective cohort study, 326 Vietnamese children aged between 1 and 14 years were followed up for two years after receiving either ciprofloxacin (70 mg/kg given over 7 d) (n = 173) or ofloxacin (45-50 mg/kg given over 3-5 d) (n = 153) for suspected typhoid fever. Growth velocity and weight for height were compared with an age matched control group of children from the same locality (n = 223) who had not contracted typhoid or received any fluoroquinolones. In the ofloxacin and ciprofloxacin treated patients there was no evidence of acute joint toxicity, nor of any joint symptoms attributable to either of the fluoroquinolones. There was no difference in expected weight for height measurements between the three groups of children over the two year period. During the first year, height velocity in ciprofloxacin treated children was greater than in either ofloxacin treated children or untreated controls. Height velocity in the latter two groups was not significantly different. After two years height velocity was similar in the three groups. The results support the use of short course fluoroquinolone treatment in childhood typhoid, especially when caused by strains resistant to other antibiotics. 相似文献
182.
Total plasma androgens (PA) were measured in 9 hypogonadal males aged between 13 and 21 1/2 years after a single oral dose of testosterone undecanoate (TU). With the exception of one patient, all showed a rise in PA with peak values between 7.7 and 38.0 nmol/l at 2 to 7 hours. A further patient aged 15.7 years who was given an 80-mg dose had a peak PA level of 71.2 nmol/l. In all patients PA returned to basal levels at 24 hours. In 4 patients plasma testosterone and dihydrotestosterone were measured, both rose after oral TU, and relatively high plasma dihydrotestosterone values were obtained. While these results indicate that TU is effective in young people, the very high peak androgen levels found in several of them after 40 mg TU suggest that this dose may be excessive in patients in whom growth is not complete. 相似文献
183.
Mucociliary tracheal transport rates were measured in 20 patients with cystic fibrosis, in whom these rates ranged from 0 to 12.8 mm/min. The patients were divided into 3 roughly equal groups on the basis of their transport rates. (1) Those in whom no abnormality in mucociliary transport was detected in the trachea; (2) those in whom normal transport rates were measured but in whom abnormalities such as cessation, or reversal of bolus movement were observed; (3) those in whom no normal transport rates were observed. In the first group the rates were similar to those observed in a population of healthy adults. These normal rates were observed in some patients who had a productive cough. The mean mucociliary tracheal transport rate increased with increasing maximum midexpiratory flow. Those patients with a low Shwachman score and poor arterial oxygen tension tended to fall into groups 2 and 3. In the ciliary dyskinesia assay in rabbit trachea the serum from the patients with the higher transport rates tended to initiate more rapid discharge of material from the epithelium and ciliary dyskinesia. 相似文献
184.
Intracerebral pneumatoceles following facial trauma: CT findings 总被引:1,自引:0,他引:1
Three patients with delayed frontal intracerebral pneumatoceles following facial injury are presented. In one patient an unusual appearance of bilateral and symmetrical frontal lobe pneumatoceles was demonstrated. While diagnosis is not difficult on routine radiographs, CT is valuable for determining effects on the brain and clearly delineating the fracture site; CT shows the location of the pneumatocele and may show an associated air-fluid level, mass effect or surrounding edema, or rim enhancement following administration of contrast material. The radiological appearances in conjunction with the clinical findings are highly characteristic and should not be mistaken for gas-forming cerebral abscesses. 相似文献
185.
186.
Satarug S; Haswell-Elkins MR; Sithithaworn P; Bartsch H; Ohshima H; Tsuda M; Mairiang P; Mairiang E; Yongvanit P; Esumi H; Elkins DB 《Carcinogenesis》1998,19(3):485-491
This study investigated the relationship between immune responses to
infection with the liver fluke, Opisthorchis viverrini, and the synthesis
of the carcinogen, N-nitrosodimethylamine (NDMA) in humans. It also
examined associations between synthesis of nitric oxide (NO) and
nitrosation of amines, in vivo. Antibody and T cell responses to fluke
antigens and post-alcohol urinary NDMA excretion were assessed among three
groups of 40-50 men with no, moderate and heavy liver fluke infection.
Markers of NO synthesis (nitrate, nitrite) and nitrosation (nitrosamino
acids) were also measured in biological fluids. Assessments were carried
out under controlled conditions which minimised intake of exogenous nitrate
and nitrite and were carried out at two time points, namely before and 4
months after elimination of the infection with praziquantel treatment. No
statistically significant variation was observed in the amount of NDMA
excreted between the 3 groups. However, during active infection, a strong
negative association was observed between in vitro lymphoproliferative
responses to some liver fluke antigens and NDMA excretion. After treatment
this association was reduced. Multivariate statistical models revealed a
highly significant relationship between NDMA levels and urinary nitrate,
stimulation indices for two T cell responses to two parasite antigens (MW
37 kDa and 110 kDa) and gall bladder dimensions. NDMA levels after
treatment were best described by the ratio between parasite-specific IgG2
and IgE, background levels of T cell proliferation, a urinary marker of
nitrosation (N-nitrosothioproline) and usual level of alcohol consumption.
These results suggest that individual background immunologic activity,
parasite-specific responses and/or parasite products and NO synthesis are
important determinants of endogenous generation of nitrosamines in O.
viverrini-infected humans.
相似文献
187.
H-cadherin is a newly characterized cadherin molecule whose expression is
decreased in a variety of human carcinoma cells, suggesting that it may
play a role in maintaining normal cellular phenotype. To investigate how
re-expression of H-cadherin could influence the malignant phenotype of
human breast carcinoma cells in vivo, we transfected both control and
H-cadherin expression vectors into human breast cancer cells (MDAMB435),
which do not express H-cadherin constitutively. We found that invasiveness
of these cells could be prevented by transfection with H-cadherin. We also
compared the ability of control- and H-cadherin-transfected cells to induce
subcutaneous tumors after injection into mammary fat pads of nude mice. Our
results show that H-cadherin transfection produced a marked inhibition of
tumor growth and modified the morphology of tumor cells: tumors from mice
injected with control cells were significantly larger and contained larger
cells having a higher degree of pleomorphism than those of tumors generated
from carcinoma cells expressing H-cadherin. Altogether, these results
indicate that H-cadherin expression antagonizes tumor growth in nude mice,
presumably by enhancing cell- cell association in a tissue environment.
These findings strongly suggest that H-cadherin could provide a possible
target for corrective gene therapy against breast cancer.
相似文献
188.
189.
JM Bhatavdekar DD Patel NH Karelia HH Vora N Ghosh NG Shah DB Balar SN Trivedi 《Breast cancer research and treatment》1994,30(3):293-297
Summary A retrospective study was performed on 69 breast cancer patients (stage II, N=18; advanced disease, N=51) in order to assess the prognostic value of circulating prolactin (PRL), CEA, CA 15-3, insulin-like growth factor-1 (IGF-1), and epidermal growth factor (EGF) by RIA/IRMA. These markers were compared with short-term prognosis (two years). Significant difference was observed only for PRL (<20.0 ng/ml vs. >20.0 ng/ml), which provide an independent predictor of short-term prognosis in advanced breast cancer. 相似文献
190.
DB Grant 《Archives of disease in childhood》1994,70(6):464-468
The growth of 361 children with congenital hypothyroidism diagnosed by screening was assessed by estimating mean values for height, weight, body mass index (BMI), and head circumference on each birthday up to the age of 4 years. In the group of children with severe congenital hypothyroidism (pretreatment plasma thyroxine < or = 30 nmol/l), the mean heights at 1 and 2 years were less than standards for healthy children, but this may be due to technical factors related to difficulties in measuring young infants and the method used to estimate height on each birthday. By the age of 3-4 years the values for mean height in the children with either severe or less severe congenital hypothyroidism were equal to or greater than those for healthy children. At all ages mean head circumference in boys and girls with severe congenital hypothyroidism was greater than standards for healthy children, but this only reached statistical significance in girls at 1 year. With the exception of the results for boys at 1 year, mean values for BMI were slightly greater in the children with severe congenital hypothyroidism. The mean BMI results for children with either severe or less severe congenital hypothyroidism were significantly greater than those for healthy French children at all ages, but they showed the same trends with increasing age. It is concluded that by the age of 3-4 years stature is essentially normal in children with early treated congenital hypothyroidism but that the increased head size reported before screening may still be evident in early infancy. 相似文献