全文获取类型
收费全文 | 3462篇 |
免费 | 181篇 |
国内免费 | 18篇 |
学科分类
医药卫生 | 3661篇 |
出版年
2024年 | 4篇 |
2023年 | 20篇 |
2022年 | 60篇 |
2021年 | 114篇 |
2020年 | 80篇 |
2019年 | 114篇 |
2018年 | 134篇 |
2017年 | 88篇 |
2016年 | 100篇 |
2015年 | 116篇 |
2014年 | 162篇 |
2013年 | 191篇 |
2012年 | 275篇 |
2011年 | 300篇 |
2010年 | 152篇 |
2009年 | 152篇 |
2008年 | 234篇 |
2007年 | 243篇 |
2006年 | 205篇 |
2005年 | 234篇 |
2004年 | 181篇 |
2003年 | 180篇 |
2002年 | 141篇 |
2001年 | 27篇 |
2000年 | 27篇 |
1999年 | 23篇 |
1998年 | 17篇 |
1997年 | 10篇 |
1996年 | 5篇 |
1995年 | 7篇 |
1994年 | 6篇 |
1993年 | 6篇 |
1992年 | 7篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1988年 | 6篇 |
1987年 | 2篇 |
1985年 | 2篇 |
1983年 | 2篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1979年 | 4篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1973年 | 1篇 |
1972年 | 4篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有3661条查询结果,搜索用时 0 毫秒
11.
12.
Marieke C. J. Dekker Adnan M. Sadiq Mubashir A. Jusabani Vivian J. Mdavire Frank Baas David H. Morton Ben C. J. Hamel 《American journal of medical genetics. Part A》2019,179(10):2034-2038
We report an African infant with Ellis‐van Creveld (EVC) syndrome. EVC syndrome is a chondral and ectodermal dysplasia with autosomal recessive transmission. The baby presented with polydactyly, short limbs and atrioventricular septal defect, but was withdrawn from clinical follow up for the first year of life. Initial hematological abnormalities could not be explained and normalized later. EVC syndrome was confirmed by genetic analysis that showed two pathogenic mutations in the EVC2 gene, c.653_654del, p.Val218Glyfs*12 in exon 5, and c.2710C>T, p.Gln904* in exon 16. The variant c.653_654del; p.Val218Glyfs*12 in exon 5 has not been described before. Our review of medical literature suggested this is the first molecularly confirmed case of EVC syndrome in sub‐Saharan Africa. 相似文献
13.
Relationship among pulmonary function, bronchial reactivity, and exhaled nitric oxide in a large group of asthmatic patients. 总被引:7,自引:0,他引:7
Stephen J Langley Sophie Goldthorpe Adnan Custovic Ashley Woodcock 《Annals of allergy, asthma & immunology》2003,91(4):398-404
BACKGROUND: Bronchial reactivity and exhaled nitric oxide (eNO) are not often used to monitor control and severity of asthma in clinical practice. OBJECTIVE: To evaluate the relationship among different physiologic measures (pulmonary function, nonspecific bronchial reactivity, and eNO) in asthmatic patients. METHODS: Cross-sectional, hospital-based study conducted in patients with varied asthma severity. RESULTS: A total of 392 patients participated in the study. There was no difference in eNO levels between patients taking inhaled corticosteroids (ICS group) and patients not receiving inhaled corticosteroids (NICS group). However, the percentage of predicted forced expiratory volume in 1 second (FEV1) and the provocative dose of methacholine causing a 20% decrease in FEV1 were significantly lower in the ICS group compared with the NICS group (mean, 83.2%; 95% confidence interval [CI], 80.4%-86.0%; vs mean, 94.1%; 95% CI, 91.1%-97.1%; P = .001; and geometric mean, 0.32 mg; 95% CI, 0.23-0.45 mg; vs geometric mean, 0.58 mg; 95% CI, 0.42-0.81 mg; P = .01; respectively). Patients with more severe bronchial hyperresponsiveness had a lower percentage of predicted FEV1 values (P < .001) and levels of eNO were significantly increased with increasing bronchial hyperresponsiveness (P < .001). There was no relationship between the percentage of predicted FEV1 and eNO. Atopic patients had significantly higher eNO levels than nonatopic patients (geometric mean, 11.21 ppb; 95% CI, 10.07-12.49 ppb; vs geometric mean, 7.76 ppb; 95% CI, 6.11-9.85 ppb; P = .006; respectively). CONCLUSIONS: eNO values are not related to the degree of airway obstruction but are related to airway reactivity and atopic status independent of inhaled corticosteroid use. Higher values of eNO are seen with increased airway reactivity. 相似文献
14.
Molecular epidemiology of macrolide-resistant Streptococcus pneumoniae isolates in Europe 总被引:3,自引:0,他引:3
Reinert RR Ringelstein A van der Linden M Cil MY Al-Lahham A Schmitz FJ 《Journal of clinical microbiology》2005,43(3):1294-1300
In many European countries, the level of pneumococcal resistance to macrolides has now passed the level of resistance to penicillin G. A total of 82 erythromycin A-resistant isolates of Streptococcus pneumoniae were collected by 11 laboratories in seven European countries. All of the isolates were tested for antimicrobial susceptibility, analyzed for clonal relatedness by multilocus sequence typing, and characterized for macrolide resistance genotypes. The prevalence of the macrolide resistance genotypes varied substantially between countries. In France (87.5% of all strains), Spain (77.3%), Switzerland (80%), and Poland (100%), strains were predominantly erm(B) positive, whereas higher levels of mef(A)-positive strains were reported from Greece (100%) and Germany (33.3%). Macrolide resistance was caused by the oligoclonal spread of some multilocus sequence types, but significant differences in clonal distribution were noted between France and Spain, countries from which high levels of macrolide resistance have been reported. Overall, sequence type 81 (Spain23F-1 clone) was by far the most widespread. The mainly erm(B)-positive serotype 14 clone (sequence type 143), first reported in Poland in the mid-1990s, is now widespread in France. 相似文献
15.
Neoplastic myoepithelium is considered to be the key cellular participant in morphogenetic processes responsible for the variable histologic appearances of many salivary gland tumors. Nevertheless, controversy still exists concerning its participation in some types of salivary gland neoplasms. This has been largely due to the difficulty in fully characterizing the wide spectrum of morphologic and immunophenotypic expressions of neoplastic myoepithelium compared with the normal counterpart. However, in recent years, our understanding regarding the phenotypic, immunophenotypic, ultrastructural, and biochemical properties of myoepithelium has advanced. Here we discuss the role of neoplastic myoepithelium in the scope of salivary gland neoplasia and present this information from a practical diagnostic standpoint. 相似文献
16.
17.
18.
David M. Vail Adnan A. Elfarra A. James Cooley David L. Panciera E. Gregory MacEwen Steve A. Soergel 《Cancer chemotherapy and pharmacology》1993,32(1):25-30
Dexniguldipine-HCl (DNIG) — a prospective clinical modulator of p170-glycoprotein (pgp170)-mediated multidrug resistance (MRD) — was evaluated in a drug-accumulation assay in MDR murine leukemia cell strain F4-6RADR expressing pgp170. The compound elevated low accumulation of either doxorubicin (DOX), daunorubicin (DNR), or mitoxantrone (MITO) in resistant F4-6RADR cells to the very levels observed in drug-sensitive F4-6 precursor cells. In parallel with the increase in DNR content (F4-6RADR, solvent: 303±27 pmol/mg protein; DNIG (3.3 mol/l): 1,067±174 pmol/mg protein; F4-6P, solvent: 948±110 pmol/mg protein;n=8–9, SEM), the amount of DNR tightly bound to the acid precipitate pellet obtained from F4-6RADR (i.e., protein, DNA, RNA) increased 3.9-times to the levels observed in sensitive F4-6 cells. The main pyridine metabolite of DNIG displayed similar activity. Concentration-response analysis revealed that DNIG and R,S-verapamil (VER) induced 100% reversal of the DNR accumulation shortage associated with the MDR phenotype but DNIG was 8 times more potent than VER (50% inhibitory concentration (IC50), 0.73 vs 5.4 mol/l). In keeping with the accumulation assay, DNIG was about 10 times more potent than VER in sensitizing F4-6RADR cells to the cytostatic and cytotoxic effects of DNR in proliferation assays. In conclusion, DNIG is a potent in vitro modulator, improving (a) the accumulation of anthracycline-like cytostatics, (B) drug access to cellular binding sites, and (c) the cytostatic action of DNR in F4-6RADR leukemia cells of the MDR phenotype.Abbreviations DOX
doxorubicin
- CSA
cyclosporin A
- DMSO
dimethylsulfoxide
- DNIG
dexniguldipine-HCl
- DNR
daunorubicin
- MDR
multidrug resistance
- MITO
mitoxantrone
- pgp170
permease glycoprotein 170
- VER
R.S.-verapamil
Dexniguldipine-HCl is the proposed INN for compound B859-35, the R-enantiomer of niguldipine. Segments of this work have been reported in the abstract form 相似文献
19.
Suzanne M. Jacques Faisal Qureshi Barbara J. Doss Adnan Munkarah 《Pediatric and developmental pathology》1998,1(5):380-387
Choriocarcinoma arising in the placenta, or intraplacental choriocarcinoma, has seldom been reported, particularly in the
absence of maternal metastases. Reluctance to diagnose choriocarcinoma in the presence of chorionic villi can delay diagnosis;
however, timely diagnosis of choriocarcinoma is prognostically important, both for the mother and infant. We report the clinicopathologic
findings in five mothers and infants in whom choriocarcinoma was identified in the placenta. None of the mothers had a history
of gestational trophoblastic disease in previous pregnancies. Three placentas were similar with a single small lesion grossly
suggesting a small infarct; microscopically these consisted of infarcted areas surrounded by choriocarcinoma. These three
mothers were unusual in that none had metastatic choriocarcinoma; two were treated with chemotherapy and remained disease-free;
the third was lost to follow-up shortly following delivery. The remaining two mothers had known pulmonary metastases at time
of delivery. One of these latter two placentas contained a large marginal lesion microscopically identified as choriocarcinoma.
The fifth placenta had rare microscopic foci of choriocarcinoma, and sheets of necrotic choriocarcinoma were identified in
“blood clot” submitted with the placenta. In four of the five cases the choriocarcinoma appeared to be arising from otherwise
normal chorionic villi, and in no case was there invasion of the villous stroma. All of the infants survived, and none had
evidence of choriocarcinoma. These cases support the concept that choriocarcinoma associated with otherwise normal pregnancy
arises in the placenta and may be more common than reported.
Received August 11, 1997; accepted December 8, 1997. 相似文献
20.
Budancamanak M Kanter M Demirel A Ocakci A Uysal H Karakaya C 《Archives of toxicology》2006,80(11):768-776
The goal of this investigation was to study the protective effects of thymoquinone (TQ) and methotrexate (MTX) on collagen-induced arthritis (CIA) in rats. On day 0 under ether anesthesia, the experimental groups were immunized with 0.5 mg native chick collagen II (CII) solubilized in 0.1 M acetic acid and emulsified in Freund's incomplete adjuvant. Control rats were gavaged with vehicle, whereas CII was administered intradermally. In addition, arthritis treated with TQ group received TQ (10 mg kg(-1) bw by gavage once a week for 3 weeks starting on day 0); and arthritis treated with MTX group received MTX (MTX was suspended in corn oil and administered by gavage at 1 mg kg (-1) bw once a week for 3 weeks starting on day 0). A significant decrease in the incidence and severity of arthritis by clinical and radiographic assessments was found in recipients of therapy, compared with that of controls. The MTX treatment significantly (P<0.01) decreased the elevated serum NO, urea and creatinine in arthritic rats. Likewise, TQ treatment was also able to reduce significantly (P<0.05) serum NO, urea and creatinine levels, but to lesser extent than MTX. The histopathologic abnormalities are consistent with the hydropic epithelial cell degenerations and moderate tubular dilatation in the some proximal and distal tubules. The severity of the degenerative changes in most of the shrunken glomerules and vascular congestion were also observed in arthritic animals. Preventive treatment of TQ and especially MTX significantly inhibited kidney dysfunction and this histopathologic alterations. These studies indicate that TQ can be used similar to MTX as a safe and effective therapy for CIA and may be useful in the treatment of rheumatoid arthritis. 相似文献