全文获取类型
收费全文 | 3578篇 |
免费 | 200篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 19篇 |
儿科学 | 142篇 |
妇产科学 | 84篇 |
基础医学 | 519篇 |
口腔科学 | 83篇 |
临床医学 | 250篇 |
内科学 | 772篇 |
皮肤病学 | 88篇 |
神经病学 | 146篇 |
特种医学 | 484篇 |
外科学 | 369篇 |
综合类 | 45篇 |
预防医学 | 312篇 |
眼科学 | 41篇 |
药学 | 264篇 |
1篇 | |
中国医学 | 9篇 |
肿瘤学 | 164篇 |
出版年
2021年 | 41篇 |
2019年 | 46篇 |
2018年 | 67篇 |
2017年 | 45篇 |
2016年 | 52篇 |
2015年 | 58篇 |
2014年 | 73篇 |
2013年 | 102篇 |
2012年 | 112篇 |
2011年 | 116篇 |
2010年 | 102篇 |
2009年 | 104篇 |
2008年 | 126篇 |
2007年 | 130篇 |
2006年 | 126篇 |
2005年 | 134篇 |
2004年 | 118篇 |
2003年 | 101篇 |
2002年 | 97篇 |
2001年 | 95篇 |
2000年 | 86篇 |
1999年 | 71篇 |
1998年 | 96篇 |
1997年 | 96篇 |
1996年 | 97篇 |
1995年 | 83篇 |
1994年 | 48篇 |
1993年 | 68篇 |
1992年 | 54篇 |
1991年 | 56篇 |
1990年 | 78篇 |
1989年 | 89篇 |
1988年 | 81篇 |
1987年 | 80篇 |
1986年 | 89篇 |
1985年 | 98篇 |
1984年 | 53篇 |
1983年 | 52篇 |
1982年 | 34篇 |
1981年 | 38篇 |
1980年 | 49篇 |
1979年 | 26篇 |
1978年 | 31篇 |
1977年 | 33篇 |
1976年 | 29篇 |
1975年 | 40篇 |
1974年 | 31篇 |
1972年 | 24篇 |
1968年 | 25篇 |
1967年 | 25篇 |
排序方式: 共有3792条查询结果,搜索用时 31 毫秒
61.
A model of corrective gene transfer in X-linked ichthyosis 总被引:5,自引:0,他引:5
Freiberg RA; Choate KA; Deng H; Alperin ES; Shapiro LJ; Khavari PA 《Human molecular genetics》1997,6(6):927-933
Single gene recessive genetic skin disorders offer attractive prototypes
for the development of therapeutic cutaneous gene delivery. We have
utilized X-linked ichthyosis (XLI), characterized by loss of function of
the steroid sulfatase arylsulfatase C (STS), to develop a model of
corrective gene delivery to human skin in vivo. A new retroviral expression
vector was produced and utilized to effect STS gene transfer to primary
keratinocytes from XLI patients. Transduction was associated with
restoration of full-length STS protein expression as well as steroid
sulfatase enzymatic activity in proportion to the number of proviral
integrations in XLI cells. Transduced and uncorrected XLI keratinocytes,
along with normal controls, were then grafted onto immunodeficient mice to
regenerate full thickness human epidermis. Unmodified XLI keratinocytes
regenerated a hyperkeratotic epidermis lacking STS expression with
defective skin barrier function, effectively recapitulating the human
disease in vivo. Transduced XLI keratinocytes from the same patients,
however, regenerated epidermis histologically indistinguishable from that
formed by keratinocytes from patients with normal skin. Transduced XLI
epidermis demonstrated STS expression in vivo by immunostaining as well as
a normalization of histologic appearance at 5 weeks post-grafting. In
addition, transduced XLI epidermis demonstrated a return of barrier
function parameters to normal. These findings demonstrate corrective gene
delivery in human XLI patient skin tissue at both molecular and functional
levels and provide a model of human cutaneous gene therapy.
相似文献
62.
63.
Jens A. Wagner Károly Varga G. Kunos 《Journal of molecular medicine (Berlin, Germany)》1998,76(12):824-836
Marijuana is a widely abused recreational drug well known for its psychoactive properties. Cannabinoids, the active ingredients
of marijuana, elicit their neurobehavioral effects by interacting with the CB1 cannabinoid receptor subtype, expressed primarily in the brain but also present in some peripheral tissues. A second receptor
subtype, the CB2 receptor, is expressed on cells of the immune system and is thought to be responsible for the immunosuppressant effects of
cannabinoids. Recently, endogenous lipidlike substances have been identified, including arachidonyl ethanolamide (anandamide)
and 2-arachidonyl glyceride, that bind to cannabinoid receptors and mimic many of the neurobehavioral effects of plant-derived
cannabinoids. Both plant-derived cannabinoids and the endogenous ligands have been shown to elicit hypotension and bradycardia
via activation of peripherally located CB1 receptors. Possible underlying mechanisms include presynaptic CB1 receptor mediated inhibition of norepinephrine release from peripheral sympathetic nerve terminals, and/or direct vasodilation
via activation of vascular cannabinoid receptors. The latter may also be the target of endocannabinoids of vascular endothelial
origin. Recent studies indicate that a peripheral endogenous cannabinoid system in circulating macrophages and platelets is
activated in hemorrhagic and septic shock and may contribute to the hypotension associated with these conditions via activation
of vascular cannabinoid receptors. The potential role of this mechanism in human shock conditions is under investigation.
Received: 20 May 1998 / Accepted: 24 August 1998 相似文献
64.
Mutational analysis of the SOX9 gene in campomelic dysplasia and autosomal sex reversal: lack of genotype/phenotype correlations 总被引:9,自引:1,他引:9
Meyer J; Sudbeck P; Held M; Wagner T; Schmitz ML; Bricarelli FD; Eggermont E; Friedrich U; Haas OA; Kobelt A; Leroy JG; Van Maldergem L; Michel E; Mitulla B; Pfeiffer RA; Schinzel A; Schmidt H; Scherer G 《Human molecular genetics》1997,6(1):91-98
It has previously been shown that, in the heterozygous state, mutations in
the SOX9 gene cause campomelic dysplasia (CD) and the often associated
autosomal XY sex reversal. In 12 CD patients, 10 novel mutations and one
recurrent mutation were characterized in one SOX9 allele each, and in one
case, no mutation was found. Four missense mutations are all located within
the high mobility group (HMG) domain. They either reduce or abolish the
DNA-binding ability of the mutant SOX9 proteins. Among the five nonsense
and three frameshift mutations identified, two leave the C-terminal
transactivation (TA) domain encompassing residues 402-509 of SOX9 partly or
almost completely intact. When tested in cell transfection experiments, the
recurrent nonsense mutation Y440X, found in two patients who survived for
four and more than 9 years, respectively, exhibits some residual
transactivation ability. In contrast, a frameshift mutation extending the
protein by 70 residues at codon 507, found in a patient who died shortly
after birth, showed no transactivation. This is apparently due to
instability of the mutant SOX9 protein as demonstrated by Western blotting.
Amino acid substitutions and nonsense mutations are found in patients with
and without XY sex reversal, indicating that sex reversal in CD is subject
to variable penetrance. Finally, none of 18 female patients with XY gonadal
dysgenesis (Swyer syndrome) showed an altered SOX9 banding pattern in SSCP
assays, providing evidence that SOX9 mutations do not usually result in XY
sex reversal without skeletal malformations.
相似文献
65.
Nouri-Aria KT Irani AM Jacobson MR O'brien F Varga EM Till SJ Durham SR Schwartz LB 《The Journal of allergy and clinical immunology》2001,108(2):205-211
BACKGROUND: Basophils represent an important source of inflammatory mediators and cytokines after IgE-dependent activation in human beings. OBJECTIVE: To assess the role of basophils in allergic asthma, we measured the number of basophils in the bronchial mucosa and their capacity to express IL-4 mRNA and protein during allergen-induced late asthmatic responses. METHODS: Fiberoptic bronchoscopic bronchial biopsies were obtained at 24 hours from sites of segmental bronchial allergen challenge and control sites in 19 patients with atopic asthma and 6 nonatopic healthy volunteers. Basophil numbers were assessed by immunohistochemistry through use of mAb 2D7. IL-4 mRNA--positive cells were detected through use of in situ hybridization and colocalized to basophils through use of sequential immunohistochemistry/in situ hybridization. IL-4 protein was detected and colocalized to basophils through use of dual immunohistochemistry. RESULTS: After allergen challenge, there was an increase in the median number of 2D7-positive basophils per square millimeter in the bronchial mucosa in patients with asthma (0.9 cells/mm(2) at baseline to 8.8 cells/mm(2) after challenge; P =.002), which also was significantly higher than what was seen in nonasthmatic controls (P =.01). Similarly, IL-4 mRNA--positive cells were increased at 24 hours in patients with asthma (1.4 to 14) in comparison with controls (0 to 0; P =.02). Colocalization studies revealed that 15% and 41% of the basophil population in patients with asthma after allergen-challenge expressed, respectively, IL-4 mRNA and protein. Conversely, 19% of IL-4 mRNA-positive cells and 72% of IL-4 protein--positive cells were accounted for by basophils. CONCLUSION: After allergen provocation in sensitive patients with atopic asthma, basophils are recruited to the bronchial mucosa and express IL-4 mRNA and protein, which might contribute to local IgE synthesis and/or tissue eosinophilia or other aspects of allergic inflammation during late responses and ongoing asthma. 相似文献
66.
Farkas H Gyeney L Nemesánszky E Káldi G Kukán F Masszi I Soós J Bély M Farkas E Füst G Varga L 《Immunological investigations》1999,28(1):43-53
A patient with two diseases, based presumably on different immunopathological mechanisms, hereditary angioedema (HAE) and Crohn's disease, was followed for 8 years. For more than three years of this observation period, detailed laboratory data were also available and could be analyzed. Both diseases had severe courses requiring chronic treatment with danazol and sulfasalazine, respectively. During exacerbation of Crohn's disease, the levels of C4 was found to be significantly lower than during the periods free of symptoms of both diseases. This drop was probably due to an impaired C1-inhibitor activity. HAE attacks and acute exacerbation of Crohn's disease never occurred simultaneously. This finding may be a mere chance but may also indicate that the different immunopathological processes underlying HAE and Crohn's disease influence each other. 相似文献
67.
E Sántha G Répásy M Varga 《Magyar traumatológia, orthopaedia és helyreállító sebészet》1990,33(4):291-295
A thought, returning again and again in hand surgery, is the immediate introduction of active motion therapy after the reconstructive operations of the flexor tendons. To the active motion an adequately strong tendon suture, to the definition of "adequately strong tendon suture" however the measurement of the pulling force, acting actually on the flexor tendons is necessary. Authors attempted to measure this pulling force during flexor tendon operations on cadaver's hand. On the basis of their measurements the maximal pulling force, that can be expected during postoperative active movement exercises with adequate circumspection, can be estimated as two kiloponds. 相似文献
68.
J A Simonka E Varga G Kiss E V?r?s 《Magyar traumatológia, orthopaedia és helyreállító sebészet》1990,33(4):283-290
Authors studied a frequent injury of the finger joints. The anatomy, the mechanism of the injuries, the diagnostic possibilities of the lamina fibrocartilaginea ("palmar plate") and of the palmar ligaments of the joints are described. In the diagnosis a special significance is attached to the stressed and tangential X-ray pictures. They take the part of the conservative treatment of the injury. In cases of dislocations, that cannot be reduced, of open "palmar plate" injuries and of major hyperextension and dislocations of the broken bone scale, operative treatment is thought necessary. In the treatment of the injuries of the "palmar plate" of the PIP joint they use the so called rein method, that keeps the palmar cartilaginous joint capsule, torn at the injury, on its original place, it enables however the active joint movements, the gymnastics and hinders this way the development of the joint contracture. 相似文献
69.
During the last 3 years 263 patients were admitted who underwent diagnostic lymph node biopsy. Complications were observed only in 4 cases. In these cases, following cervical lymph node excision from the supraclavicular region, sectioning the spinal accessory nerve and branches of brachial plexus resulted in the "shoulder syndrome" which is characterized by a weakened, deformed, and often painful shoulder. Attention is called to the possibility of nerve injury during diagnostic excision of cervical lymph nodes. Most often the spinal accessory nerve and branches of brachial plexus are transected with subsequent deformity and decreased range of motion of the shoulder, which could influence deeply the quality of patient's life. 相似文献
70.
I. Horkay M. Debreczeni L. Varga V. Mann J. Krajczár J. Csongor 《Archives of dermatological research》1981,271(2):143-147
Summary Prostaglandin F2 (PGF2) as a possible mediator was studied. Its plasma content was determined by radioimmunoassay. Changes in the DNA synthesis were followed by autoradiography. In active polymorphous light eruption (PLE) and porphyria cutanea tarda (PCT) a remarkable increase (over 300 pg/ml) in plasma content occurred, especially in cases involving large skin areas. Values returned to normal in remission. PGF2 administered i.d., significantly increased the DNA synthesis of the epidermal cells 48 h after injection similar to the effect of three minimal erythema dosis UV-irradiation. This was more pronounced in PLE patients than in controls. These findings suggest some role of PGF2 in producing the inflammatory and perhaps proliferative components of the skin symptoms in PLE. PGF2 — in parallel to literary data concerning PGE — seems to be a mediator of UV-induced changes in DNA synthesis of the epidermal cells.
Offprint requests to: Irene Horkay, MD (address see above) 相似文献