全文获取类型
收费全文 | 1441篇 |
免费 | 74篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 81篇 |
妇产科学 | 31篇 |
基础医学 | 128篇 |
口腔科学 | 29篇 |
临床医学 | 110篇 |
内科学 | 307篇 |
皮肤病学 | 24篇 |
神经病学 | 74篇 |
特种医学 | 264篇 |
外科学 | 69篇 |
综合类 | 26篇 |
预防医学 | 51篇 |
眼科学 | 7篇 |
药学 | 99篇 |
中国医学 | 1篇 |
肿瘤学 | 213篇 |
出版年
2022年 | 6篇 |
2020年 | 6篇 |
2018年 | 17篇 |
2017年 | 14篇 |
2016年 | 10篇 |
2015年 | 17篇 |
2014年 | 22篇 |
2013年 | 25篇 |
2012年 | 42篇 |
2011年 | 29篇 |
2010年 | 44篇 |
2009年 | 49篇 |
2008年 | 45篇 |
2007年 | 44篇 |
2006年 | 42篇 |
2005年 | 46篇 |
2004年 | 25篇 |
2003年 | 30篇 |
2002年 | 22篇 |
2001年 | 22篇 |
2000年 | 21篇 |
1999年 | 19篇 |
1998年 | 55篇 |
1997年 | 69篇 |
1996年 | 54篇 |
1995年 | 47篇 |
1994年 | 56篇 |
1993年 | 57篇 |
1992年 | 22篇 |
1991年 | 22篇 |
1990年 | 29篇 |
1989年 | 51篇 |
1988年 | 57篇 |
1987年 | 46篇 |
1986年 | 47篇 |
1985年 | 38篇 |
1984年 | 21篇 |
1983年 | 29篇 |
1982年 | 24篇 |
1981年 | 25篇 |
1980年 | 25篇 |
1979年 | 14篇 |
1978年 | 12篇 |
1977年 | 16篇 |
1976年 | 13篇 |
1975年 | 22篇 |
1973年 | 8篇 |
1972年 | 7篇 |
1970年 | 11篇 |
1969年 | 10篇 |
排序方式: 共有1518条查询结果,搜索用时 15 毫秒
11.
Follicular fluid renin concentration and IVF outcome 总被引:1,自引:0,他引:1
C M Cornwallis S L Skinner P L Nayudu A Lopata R L Thatcher S P Yeung J A Whitworth 《Human reproduction (Oxford, England)》1990,5(4):413-417
Total renin protein concentration (TRC) was measured in stored follicular fluid (FF) samples from 42 women. Samples were selected according to their origin from follicles either without recovered ova ('empty', n = 38) or fertilized but with failed implantation ('failed', n = 36) or successful deliveries ('deliveries', n = 71). Ratios of number of embryos transferred to number of infants delivered were 2:1, 3:1 or 4:2 but 1:1 was not available. Non-parametric testing was applied to FF-TRC, volume and outcome. TRC was significantly higher in the delivery than the failed (P = 0.001) or empty (P = 0.002) categories. Assuming that the range of renin in failed follicles can identify the sub-population of unsuccessful follicles in the delivery category, then elevated FF-TRC was clearly associated with successful outcome. For individual women, the odds of infant delivery increased 17-fold as a function of average FF-TRC between 10,000 and 25,000 microIU/ml. For failed and delivery but not empty follicles, higher renin levels occurred in the smaller follicles, consistent with a burst of renin synthesis associated with the presence of an oocyte. The results suggest that FF-TRC relates to ovum viability with ovarian hyperstimulation and may have predictive use in IVF programmes. 相似文献
12.
13.
T. Cerny J. M. Margison N. Thatcher P. M. Wilkinson 《Cancer chemotherapy and pharmacology》1986,18(3):261-264
Summary The pharmacokinetics of ifosfamide (I) were determined in ten patients with bronchogenic carcinoma. In seven patients, doses of 1 and 2 g (I) were given both as a bolus orally and later intravenously and were well tolerated. A further three patients received 5 g (I) as a single oral dose but in two this produced reversible CNS toxicity and severe vomiting. The area under the curve (AUC, g.h.l-1) for the 1-g dose was the same following oral and i. v. treatment and this was also true for the 2-g doses. There was a proportionate increase in the AUC for the 5-g oral dose, indicating 100% bioavailability at all three dose levels. We conclude that doses up to 2 g by mouth represent a well-tolerated alternative route of administration.T. Cerny is the recipient of an EORTC Research Fellowship 相似文献
14.
Osteosarcomatosis 总被引:10,自引:0,他引:10
Hopper KD; Moser RP Jr; Haseman DB; Sweet DE; Madewell JE; Kransdorf MJ 《Radiology》1990,175(1):233-239
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized. 相似文献
15.
Marrow regeneration after mechanical depletion 总被引:1,自引:0,他引:1
The origin of marrow regeneration after mechanical depletion was reinvestigated in mouse chimeras. The results were compatible with the local origin of stem cells from remnants of incompletely removed marrow, but not with their origin from a common precursor of both bone and hemopoietic cell lines. In transplanted femurs depleted by a modified technique of in vivo evacuation of marrow, hemopoietic regeneration failed to occur. The presence of hemopoietic stem cells in the Haversian canals was thus excluded. The demonstration of ample hemopoiesis with minimal bone formation in nondepleted controls in which bone marrow initially became necrotic provided new evidence that osteogenesis was not a prerequisite of hemopoietic regeneration. 相似文献
16.
JE McMICHAEL 《Journal of paediatrics and child health》1997,33(1):1-3
An understanding of the neurodevelopmental outcome of long-term survivors of neonatal intensive care is essential for the informed management of preterm or high risk infants. This annotation looks at the current status of neonatal follow-up services in Australasia and highlights problems in the collection and interpretation of data. It suggests that we should work towards achieving a consensus on standard definitions and test regimes and on national data collection. 相似文献
17.
L Patel PE Clayton ME Jenney JE Ferguson TJ David 《Archives of disease in childhood》1997,76(6):505-508
Cross sectional studies have reported impaired growth in children with atopic dermatitis. If this growth impairment is irreversible, it would be expected to adversely influence final height attainment. The standing heights and other anthropometric parameters were assessed in 35 adults with onset of atopic dermatitis before 5 years of age and a control group of 35 adults with adult onset contact dermatitis or psoriasis. There was no significant difference in the standing height SD score, mid-parental height SD score, sitting height SD score, subischial leg length SD score, nor body mass index between the atopic dermatitis and control groups. The standing height SD score was not significantly different among: (a) patients with atopic dermatitis affecting less than 50% of their body surface area and those with greater than 50% affected; (b) patients using the four different potency topical corticosteroids; and (c) patients with atopic dermatitis without asthma and those with coexisting asthma. It is concluded that short stature is not a feature of our group of adult patients with onset of atopic dermatitis before 5 years of age, continuing into adulthood, and severe enough to require specialist care. This suggests that if growth impairment occurs in childhood, it is likely to be temporary and reversible. 相似文献
18.
Dietary polyamines promote the growth of azoxymethane-induced aberrant crypt foci in rat colon 总被引:1,自引:1,他引:1
We have examined whether dietary polyamines influence the formation and
initial growth of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in
rat colon. Effects of a combination of dietary polyamines at three dose
levels (putrescine: 50, 280, 740 nmol/g; spermidine: 10, 261, 763 nmol/g;
spermine: 1, 31, 91 nmol/g) in the polyamine-poor AIN-76A diet were studied
in animals in two different experimental situations: animals treated with
AOM alone and animals treated with AOM + difluoromethylornithine (DFMO), a
specific inhibitor of endogenous polyamine synthesis. In both experimental
situations, dietary polyamines enhanced the growth of ACF, expressed as the
number of large ACF (foci with three or more aberrant crypts, ACF > or =
3), whereas the formation of ACF, expressed as the number of ACF, was
apparently not altered. In animals treated with AOM alone, maximal growth
enhancing effect on ACF was nearly obtained with the median level of
dietary polyamine. In rats fed a low polyamine diet, basic AIN-76A, DFMO
reduced the growth of AOM-induced ACF by 83%. This inhibitory effect of
DFMO was counteracted by dietary polyamines in a dose- dependent manner,
and it was abolished at the highest level of polyamines. In conclusion, it
was demonstrated that dietary polyamines are able to enhance the growth of
AOM-induced ACF. Further, dietary polyamines reversed the DFMO-caused
inhibition of ACF growth, probably by compensating for the DFMO-reduced
endogenous polyamine synthesis.
相似文献
19.
Hansen LA; Malarkey DE; Wilkinson JE; Rosenberg M; Woychik RE; Tennant RW 《Carcinogenesis》1998,19(10):1837-1845
We previously reported that papillomas can arise from the follicular
epithelium of v-Ha-ras transgenic TGxAC mice. Since the viable-yellow
mutation (A(vy)) of the mouse agouti gene which regulates coat color
pigmentation by acting within the micro-environment of the hair follicle
has been shown to function as a tumor promoter in the liver, we
hypothesized that it may also play a role in TGxAC skin tumorigenesis.
Endogenous agouti protein product was detected in the outer root sheath of
anagen hair follicles following plucking of the hair shaft, but not in the
interfollicular epithelium, in TGxAC mice on an FVB/N genetic background.
It was also detected in papillomas from these mice produced by
12-O-tetradecanoylphorbol-13-acetate (TPA) treatment or plucking.
Expression of the A(vy) allele in the v-Ha-ras transgenic TGxAC mouse line
results in an approximately 2-fold increase in papilloma development
compared with controls which did not carry the A(vy) allele following
twice-weekly treatment with 1.25, 2.5 or 5.0 microg TPA. In addition,
TPA-treated, papilloma-bearing F1 mice which carried the A(vy) allele, but
not F1 mice which did not carry the A(vy) allele, exhibited a syndrome of
humoral hypercalcemia mediated by parathyroid hormone-related protein
(PTHrP) that led to weight loss, hypercalcemia and hypophosphatemia. Thus,
we conclude that the A(vy) allele can influence the development of skin
tumors and PTHrP-mediated humoral hypercalcemia in v-Ha-ras transgenic
TGxAC mice.
相似文献
20.
Nicholas Thatcher Wendi Qian Peter I Clark Penelope Hopwood Robert J Sambrook Robert Owens Richard J Stephens David J Girling 《Journal of clinical oncology》2005,23(33):8371-8379
PURPOSE: Ifosfamide, carboplatin, etoposide, and vincristine, alone and in combination, are highly active against small-cell lung cancer (SCLC). This trial was designed to investigate whether survival could be improved by a regimen of all four drugs (ICE-V) compared with standard chemotherapy in patients with SCLC and good performance status, and to assess the patients' quality of life (QL). PATIENTS AND METHODS: Patients were randomly assigned to receive six cycles of either ICE-V at 4-week intervals without dose reduction or standard chemotherapy administered according to local practice. The recommended standard control regimens were cyclophosphamide, doxorubicin, and etoposide; and cisplatin and etoposide. RESULTS: A total of 402 patients were randomly assigned, and 350 (87%) patients have died. Overall survival was longer in the ICE-V group (hazard ratio, 0.74; 95% CI, 0.60 to 0.91; P = .0049), median survival was 15.6 months in the ICE-V group and 11.6 months in the control group, and 2-year survival rates were 20% and 11%, respectively. There was no evidence that the relative survival benefit for ICE-V was less in extensive-stage than in limited-stage patients. An increased rate of septicemia was reported in the ICE-V group (15% v 7% in the control group), but this did not result in an increase in reported treatment-related deaths (four patients [2%] in both groups). The findings on QL were broadly similar in both groups, with some benefit in favor of ICE-V. CONCLUSION: Compared with standard chemotherapy, the ICE-V regimen improves overall survival without QL penalties, despite an increased but manageable level of toxicity. 相似文献