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51.
Alopecia areata (AA) is an autoimmune disease that results in spot baldness in humans. Adequate animal models for AA are currently lacking. The objective of this study was to elucidate the mechanism of autoimmune-like alopecia (ALA) in C57BL/6.CD80CD86-deficient (B6.CD80CD86−/−) mice. Incidence and severity of alopecia were analysed in 58 B6.CD80CD86−/− mice using histological examination, flow cytometry, multiplex enzyme-linked immunosorbent assay, quantitative RT-PCR and CD25 inhibition test. Both male and female B6.CD80CD86−/− mice showed almost 100% incidence of hair loss at 40 weeks of age. Moreover, CD4+FoxP3+Treg (Treg) cell population in B6.CD80CD86−/− mice was significantly lower than in B6 mice, which presumably underlined autoimmune reaction. Histologically, B6.CD80CD86−/− mice showed CD4+ and CD8+ T-cell infiltration around terminal follicle region and exhibited hair follicle destruction in the anagen or catagen stage. Negative correlation between the number of CD4+FoxP3+ Tregs and ALA was confirmed by the CD25 depletion test in B6 mice, as follicle destruction was similar to that observed in B6.CD80CD86−/− animals. CD80CD86 deficiency disrupted CD4+FoxP3+ Treg homoeostasis and prompted the development of ALA. We demonstrated that B6.CD80CD86−/− mice might have several advantages as an ALA model, because they exhibited high incidence of disease phenotype and epipathogenesis similar to that observed in human AA.  相似文献   
52.
Skin diseases presenting with keratotic papules, atrophy, cicatricial alopecia and/or “lichenoid” histopathologic changes have been described under at least 30 names. This family of diseases contains 2 subgroups, largely based on clinical features: keratosis pilaris atrophicans (KPA; including keratosis pilaris atrophicans faciei/ulerythema ophryogenes, atrophoderma vermiculatum, and keratosis follicularis spinulosa decalvans); and the lichen planopilaris (LPP) subgroup (including LPP, frontal fibrosing alopecia, Graham‐Little‐Piccardi‐Lassueur Syndrome and fibrosing alopecia in a pattern distribution). An interface dermatitis with lichenoid inflammation is characteristic of the LPP group of disorders, but the literature provides scant information about the histopathology of the KPA group. Our experience has been that the 2 subgroups show a unifying histologic similarity as well as considerable clinical overlap. Because these conditions overlap clinically and histologically, we propose that the term lichenoid folliculitis (LF) be used to refer to this group of diseases, thus simplifying cumbersome nomenclature and highlighting the possibility of shared pathogenesis and treatment options.  相似文献   
53.
Background TrichoScan Professional is a computerized program used for digital measurement of hair growth and hair loss. The aim of our study was to undertake an evaluation with TrichoScan Professional of female patients consulting at our hospitals for hair loss. The purpose of our study was to determine whether TrichoScan was able to identify differences in hair parameters that would correlate with the pattern of alopecia or according to the age of the patients evaluated. Material and methods One hundred‐eighty women that consulted consecutively for loss of hair were included. Patients were aged between 8 and 85 years (mean age 36 years). Data including age, the number of hairs, hair density per square centimetre, anagen and telogen percentage and percentage of terminal and miniaturized hair were analysed. Results Results observed with TrichoScan were as below: number of hairs (mean 154.9; range 34–316). Hair density per square centimetre (mean 239; range 52–486). Hair in anagen phase (mean 62.4%; range 9–93%). Hair in telogen phase (mean 37.4%; range 7–91%). Terminal hair (mean 95.2%; range 82–100%). Vellus hair (mean 4.7%; range 0–17%). Pearson′s correlation test was used to measure the strength of the association of age with the rest of parameters. The statistical analysis showed a significant correlation between age and both the number of hairs and the hair density per square centimetre. However, no significant correlation between age and rest of the parameters was observed. Conclusions TrichoScan Professional may help to quantify hair density and in our sample, this was the only parameter showing a significant decrease according to age in various types of alopecia affecting the females.  相似文献   
54.
Background Several patients, especially women, seek advice because of hair loss. They may be diagnosed clinically as having telogen effluvium (TE) or androgenetic alopecia (AGA), but histopathology may reveal that a proportion of them have in fact alopecia areata incognita (AAI). Objectives To detect dystrophic anagen hairs in such patients. Methods We studied 1932 patients with hair loss and no signs of classical alopecia areata. They were submitted to the modified wash test (which counts the total number of telogen hairs lost and the percentage of vellus hairs) and divided into patients having pure TE (403), patients with AGA + TE (1235) and patients with pure AGA (294). Dystrophic hairs were detected with a low magnification microscope. Results Dystrophic hairs were observed in 13 patients with TE (3.2%), in 54 with AGA + TE (4.4%) and in none with AGA. In addition, 7 patients with TE and 32 with AGA + TE developed small patches of alopecia areata in 6 to 9 weeks. No patches developed in patients with AGA. Conclusions The presence of dystrophic hairs and the development of patches of alopecia areata (and their absence in pure AGA) provide a first evidence of the possibility that within the heterogenous condition named TE some patients have in fact AAI.  相似文献   
55.
Androgenic‐anabolic steroids (AAS) have been associated with an increased incidence of tendon rupture. The aim of this study was to compare the biomechanical properties of the rat calcaneal tendon (CT), superficial flexor tendon (SFT), and deep flexor tendon (DFT), and to determine the effect of jump training in association with AAS. Animals were separated into four groups: sedentary, trained, AAS‐treated sedentary rats (AAS), and AAS‐treated and trained animals. Mechanical testing showed that the CT differed from the DFT and SFT, which showed similar mechanical properties. Jump caused the CT to exhibit an extended toe region, an increased resistance to tensional load, and a decreased elastic modulus, characteristics of an elastic tendon capable of storing energy. AAS caused the tendons to be less compliant, and the effects were reinforced by simultaneous training. The DFT was the most affected by training, AAS, and the interaction of both, likely because of its involvement in the toe‐off step of jumping, which we suggest is related to the rapid transmission of force as opposed to energy storage. In conclusion, tendons are differently adapted to exercise, but responded equally to AAS, showing reduced flexibility, which is suggested to increase the risk of tendon rupture in AAS consumers.  相似文献   
56.
祛脂防脱片治疗早期雄激素源性脱发疗效观察   总被引:1,自引:0,他引:1  
目的:观察祛脂防脱片治疗早期雄激素源性脱发(AGA)的临床疗效。方法:84例早期脱发患者,随机分为试验组和对照组。试验组48例服祛脂防脱片,对照组36例服除脂生发片,治疗1个月为1个疗程,疗程结束后统计分析。结果:两组有效率分别为60.42%、22.22%,试验组疗效优于对照组(P<0.01)。结论:祛脂防脱片治疗早期雄激素源性脱发(AGA)临床效果好。  相似文献   
57.
介绍中医辨证治疗雄激素源性脱发的临床经验。临床分为湿热熏蒸证、阴虚血瘀证,治疗上重视辨病与辨证相结合,内治与外治相结合。  相似文献   
58.
A child is described with rickets and alopecia who did not respond to high doses of vitamin D3 but who responded to a small dose of 1--hydroxyvitamin D3. Treatment was continued for 2 years and then stopped. She has not shown any signs of relapse 1 year after stopping treatment. Her alopecia, however, has remained unchanged. One year after stopping treatment, her serum 25-hydroxycholecalciferol and parathormone levels were within normal limits but serum 1,25-dihydroxycholecalciferol was elevated.Abbreviations 25 OH D3 25-hydroxycholecalciferol - 1,25 (OH)2 D3 1,25-dihydroxycholecalciferol - 1--OH D3 1--hydroxy vitamin D - VDDR II vitamin D dependent rickets type II  相似文献   
59.
Modulation of GABA(A) receptors induced by both anabolic androgenic steroids (AAS) and the benzodiazepine (BZ) site agonist, zolpidem, show equivalent dependence upon gamma subunit composition suggesting that both compounds may be acting at a shared allosteric site. Here we have characterized modulation induced by the AAS, 17alpha-methyltestosterone (17alpha-MeT), for responses elicited from alpha(1)beta(3)gamma(2L) GABA(A) receptors and compared it to modulation induced by the BZ site agonists, zolpidem and diazepam. For responses elicited by brief pulses of 20 microM GABA, both the AAS and the BZ site compounds significantly increased the peak current amplitudes and total charge transfer, although 17alpha-MeT was an appreciably weaker agonist than either diazepam or zolpidem at alpha(1)beta(3)gamma(2L) receptors. Neither class of modulator enhanced peak current amplitudes for responses elicited by mM concentrations of GABA. BZ site compounds altered time constants of deactivation, desensitization, and recovery from desensitization, however 17alpha-MeT had no overall effect on these parameters. Experiments in which 17alpha-MeT and BZ site ligands were applied concomitantly indicated that potentiation elicited by 17alpha-MeT and zolpidem were additive and that potentiation by 17alpha-MeT could be elicited in the presence of concentrations of flumazenil that blocked BZ potentiation. Finally, kinetic modeling suggests that while effects of 17alpha-MeT can be simulated by altering receptor affinity, the data for these alpha(1)beta(3)gamma(2L) receptors were best fitted by simulations in which 17alpha-MeT increases transitions into the singly liganded open state. Taken together, our results suggest that 17alpha-MeT does not act at the high-affinity BZ site, but may elicit some of its effects at the low affinity BZ site or at a novel site.  相似文献   
60.
BACKGROUND: The interrelationship between female alopecia and psychological disorders is complex, with a range of psychosocial consequences, but also antecedents. Psychosocial antecedents are to a large extent interpersonal and can be assumed to have a mediating effect on health care utilization and subjective health. OBJECTIVES: To analyse whether changes in health-related quality of life (QoL) are mediated by relational or attachment styles and whether these styles are associated with a particular, dysmorphophobic type of alopecia. METHODS: Seventy-four women with androgenetic and diffuse alopecia underwent psychological assessment at the first consultation at a university clinic and at 2 months' follow-up. Attachment styles were evaluated by an observer rating scale. As a primary endpoint a disease-specific QoL instrument was employed. RESULTS: Findings indicated an association between patients with nonvisible hair loss and the ambivalent attachment style. Global clinical impressions and attachment indicators, e.g. attachment security and coping strategies, showed significant contributions in predicting changes in the QoL scales 'self-esteem' and 'emotions'. CONCLUSIONS: These findings suggest that attachment security may be one of the underlying mechanisms mediating subjective health and that a specific attachment vulnerability can be identified in a subgroup of patients with female alopecia. Future studies will have to focus on the relevance of attachment patterns in the doctor-patient relationship and on psychotherapeutic interventions.  相似文献   
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