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71.
魔芋精粉的降血糖作用 总被引:6,自引:0,他引:6
目的:研究魔芋精粉的降糖作用。方法:以不同剂量魔芋精粉ig正常小鼠和四氧嘧啶糖尿病小鼠,连续10d后,葡萄糖氧化酶法测定正常小鼠的空腹血糖、糖耐量试验以及四氧嘧 啶糖尿病小鼠的血糖尿病小鼠的血糖,以放射免疫法测定血清胰岛素。结果:魔芋精粉有降低正常小鼠血糖作用,呈一定量效关系趋势;且具有改善小鼠糖耐量作用,能明显降低四氧嘧啶糖尿病小鼠血糖,但因清胰岛素水平无明显影响。结论:魔芋精粉可能是通过影响糖代 相似文献
72.
K Müller-Decker G Reinerth P Krieg R Zimmermann H Heise C Bayerl F Marks G Fürstenberger 《International journal of cancer. Journal international du cancer》1999,82(5):648-656
Expression of prostaglandin-H-synthase (PGHS) isozymes was analyzed in 50 biopsies of normal human skin and of pre-malignant and malignant skin lesions, by means of quantitative RT-PCR, immunoprecipitation and Western blotting, as well as immunohistochemistry. Normal skin constitutively expressed PGHS-1 in all cell layers of the epidermis, in endothelial cells of small blood vessels and in sweat-gland epithelium. PGHS-2 expression was very low and restricted to a few keratinocytes of the interfollicular and follicular epidermis. Steady-state concentrations of PGHS-1 and PGHS-2 mRNA were similar in normal skin and in basal-cell carcinomas, but PGHS-1 mRNA was reduced and PGHS-2 mRNA was elevated in actinic keratoses, squamous-cell carcinomas and keratoacanthomas. PGHS-1 protein was detected in all tumor biopsies, being occasionally increased in basal-cell carcinomas. High amounts of PGHS-2 protein were found in actinic keratoses, squamous-cell carcinomas and keratoacanthomas, but not in basal-cell carcinomas. Four malignant melanomas included in this study contained PGHS-1 but no PGHS-2 protein. Immunohistochemical analysis of the biopsies identified keratinocytes, in addition to cells of inflammatory infiltrates and of dendritic morphology, as the major PGHS-expressing cell types. PGHS-2-specific signals were spread throughout the epidermal part of actinic keratoses and squamous-cell carcinomas. These data suggest that constitutive up-regulation of PGHS-2 expression is a consistent pre-malignant event in squamous-cell cancer development in man, as it is in animal models of skin carcinogenesis. Thus, pre-cancerous lesions such as actinic keratoses present a likely target for chemoprevention of skin cancer by selective PGHS-2 inhibitors. 相似文献
73.
Efficacy of a replication-competent adenovirus (ONYX-015) following intratumoral injection: intratumoral spread and distribution effects 总被引:8,自引:0,他引:8
ONYX-015 is an E1B-deleted adenovirus that replicates in and causes lysis of p53-deficient cancer cells selectively. To study the efficiency of intratumoral (i.t.) spread by ONYX-015, we infected specific fractions of tumor cells (two p53-deficient tumor lines and one p53 functional line) in vitro before subcutaneous inoculation into nude mice. Infection of as few as 5% of p53- tumor cells prevented tumor development in all cases; infection of 1% of p53- tumor cells resulted in significant growth inhibition but did not prevent tumor formation. In contrast, infection with ONYX-015 had no significant effect on p53+ tumor formation. These data suggested that replication-dependent tumor cell lysis and spread was occurring, but that tumor destruction might be improved by increasing i.t. virus distribution. Two treatment parameters were then varied to determine whether virus distribution, and consequently efficacy, could be improved. Divided i.t. injections of virus were more efficacious than a single injection of the same total dose. Likewise, increasing the volume of the viral suspension for i.t. injection allowed better distribution within the tumor mass and increased efficacy. These results have implications for the treatment of cancer patients with viral agents. 相似文献
74.
The distinction between true and suspected poisoning in children has not been made clear in previous work on childhood poisoning. A study of suspected poisoning in children under 15 years of age in a defined population of North East Bristol from November 1970 to July 1973 carried out by the Health Education Council Medical Research Division included 53,000 child-years at risk. The number of suspected poisonings was 3-4/1000 population aged under 15 years per year, with a higher incidence in younger age groups. Detailed investigation of the circumstances of the accidents carried out by a multidisciplinary team showed that at least 65%, and possibly as many as 78% were poisoning scares and not true poisoning. The evidence used by the casualty doctor and by the parents to diagnose poisoning was explored, and in many cases was circumstantial. Children with fathers in nonmanual occupations were over-represented. This may reflect differences in patterns of utilization behaviour rather than true differences in incidence. 相似文献
75.
S. Arnolds B. Kuglin C. Kapitza T. Heise 《International journal of clinical practice》2010,64(10):1415-1424
This pedagogical review illustrates the differences between pharmacokinetic (PK) and pharmacodynamic (PD) measures, using insulin therapy as the primary example. The main conclusion is that PD parameters are of greater clinical significance for insulin therapy than PK parameters. The glucose‐clamp technique, the optimal method for determining insulin PD, is explained so that the reader can understand the important studies in the literature. Key glucose‐clamp studies that compare two basal insulin analogues – insulin glargine and insulin detemir – to Neutral Protamine Hagedorn insulin and to each other are then presented. The review further explains how PD parameters have been translated into useful clinical concepts and simple titration algorithms for everyday clinical practice. Finally, the necessity of overcoming patient and/or physician barriers to insulin therapy and providing continuing education and training is emphasised. 相似文献
76.
77.
Clifford S. Cho Merril T. Dayton Jon S. Thompson Walter A. Koltun Charles P. Heise Bruce A. Harms 《Journal of gastrointestinal surgery》2008,12(7):1221-1226
Background The association between primary sclerosing cholangitis (PSC) and ulcerative colitis (UC) often mandates their contemporaneous
management. Orthotopic liver transplantation (OLTX) has emerged as the only curative therapy for PSC, and total proctocolectomy
with ileal pouch-anal anastomosis (IPAA) is the definitive treatment for refractory UC. The published experience to date describing
IPAA after OLTX has been limited; we sought to examine outcomes associated with proctocolectomy-IPAA after OLTX.
Materials and Methods We reviewed our multi-institutional experience performing proctocolectomy-IPAA for UC after OLTX for PSC.
Results Twenty-two patients underwent proctocolectomy-IPAA for UC after OLTX for PSC at four academic medical centers between 1989
and 2006. No perioperative complications or allograft dysfunction were observed. During a median follow-up of 52 months, complications
have included transient dehydration (n = 6), chronic pouchitis (n = 2), recurrent PSC (n = 2), small bowel obstruction (n = 2), and pouch-anal anastomotic stricture (n = 1). Median 24-h stool frequency was 5, and fecal continence was reported as satisfactory by all patients.
Conclusions This multi-institutional experience suggests that proctocolectomy-IPAA can be performed safely after OLTX. Management strategies
should include optimization of small bowel length during pouch and ileostomy construction, vigorous postoperative hydration,
early ileostomy closure, and careful monitoring for pouchitis. 相似文献
78.
Using sequences of the ribosomal second internal transcribed spacer (ITS2), PCR primers were designed for the differentiation
of the gastrointestinal nematode genera Ostertagia, Cooperia, Nematodirus, Haemonchus and Trichostrongylus. Single eggs or larvae from faeces could be differentiated without previous DNA extraction. Quantification of the PCR result
proved to be difficult because the DNA content between eggs from fresh or 24-h-old faeces varied considerably.
Received: 12 February 1999 / Accepted: 2 May 1999 相似文献
79.
Dysphagia as the Sole Manifestation of Bilateral Strokes 总被引:2,自引:0,他引:2
Anthony Celifarco M.D. Gary Gerard M.D. David Faegenburg M.D. Robert Burakoff M.D. F.A.CP. 《The American journal of gastroenterology》1990,85(5):610-613
Dysphagia can be caused by a host of factors, most of which are structural or functional. However, despite extensive evaluations, a certain number of patients have unexplained dysphagia. We present an extremely unusual case whereby a patient with an acute left hemispheric cerebral vascular accident presents with dysphagia as his sole complaint and after extensive neurological, gastroenterological, and radiographic examinations is found to have cricopharyngeal dysfunction. The etiology of this defect was not at all clinically apparent and, ultimately, magnetic resonance imaging (MRI) was performed which revealed a chronic infarction of the right frontal lobe and a smaller acute infarction in the same location of the left. This case demonstrates that swallowing disorders may be the sole presentation of stroke and that, if extensive evaluations of such patients fail to yield an etiology, one must strongly consider MRI as a tool for diagnosis, even if a CT scan is negative. 相似文献
80.