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41.
BACKGROUND: The analysis of epidemic influenza virus has been focused on antigenic and genomic characterization of the hemagglutinin (HA) glycoprotein in order to detect new variants for the recommendation of the vaccine strains in each season. Since October 1998, WHO organized a second meeting to evaluate the vaccine formula for the southern hemisphere. OBJECTIVES: (a) Present the antigenic and genomic characterization of influenza strains obtained from the Argentina surveillance network, (b) compare between strains collected in Argentina and other countries with the vaccine formula strains used in each season. STUDY DESIGN: Influenza strains were collected during a 5-year period (1995-1999). Initially, laboratory diagnosis was done by immunofluorescence (IF) assay on clinical samples, followed by viral isolation in Madin-Darby canine kidney (MDCK) cells. The isolates were characterized antigenically by hemagglutination-inhibition (HI) assay with post-infection ferret antisera. The genomic characterization consisted on RT-PCR followed by sequencing of the HA1 portion of the HA gene. The comparison between reference and circulating strains was analyzed by the construction of phylogenetic trees. RESULTS: The H3N2 circulating strains matched the corresponding vaccine component only in 1999, the first year when a vaccine recommended specifically for the southern hemisphere was used. Besides, H1N1 circulating strains matched the corresponding vaccine component only in 1998. Regarding to influenza B, only in 1995, the circulating strains showed no match to the B vaccine component. CONCLUSIONS: The results showed the usefulness of an intensified influenza laboratory surveillance to access the correct vaccine and the importance of having the necessary tools to characterize the circulating strains.  相似文献   
42.
We have analysed B chromosome frequency for three consecutive years, B transmission rate at population and individual levels, clutch size, egg fertility and embryo–adult viability in a natural population of the grasshopper Eyprepocnemis plorans containing two different B chromosome variants, i.e. B2 and B24, the second being derived from the first and having replaced it in nearby populations. From 2002 to 2003 the relative frequency of both variants changed, although the differences did not reach significance. A mother–offspring analysis showed no significant effect of any of the two B variants on clutch size, egg fertility or embryo–adult viability, but B24 was more efficiently transmitted than B2 through males from the 2002 season, which explains the observed frequency change. Controlled crosses, at individual level, showed significant drive through some females for B24 but not for B2, suggesting that this difference in transmission rate might also be important for the substitution process. The analysis of relative fitness for B2 and B24 carriers for all fitness components, as a whole, showed a significantly better performance of B24-carrying individuals, suggesting that the cumulative effect of these slight differences might contribute to the replacement of B2 by B24. Electronic Supplementary Material Supplementary material is available for this article at .  相似文献   
43.
Objective Temporomandibular joint dysfunction (TMD) may affect a patient’s quality of life, and one of the etiologies can be anterior disc displacement with reduction (ADDwR) and anterior disc displacement without reduction (ADDWoR). Interleukin 1 Receptor 1 (IL-1R1) is a membrane receptor that plays an important role on initiating immune and inflammatory response by binding the agonists ligands of IL-1 alpha and IL-1 beta. Therefore, the aim of this study was to evaluate, through immunohistochemical analysis, the association of IL-1R1 with TMD.

Methods Thirty-nine human disc samples were collected and composed three different groups: ADDwR (n = 19), ADDwoR (n = 12), and control group (n = 8). The samples were immunostained with IL-1R1 antibody and evaluated on both quantity and intensity of staining.

Results There was a statistically significant difference (p < 0.05) between the control and test groups for both quantity and intensity of staining.

Conclusion IL1-R1 was associated with ADDwR and ADDwoR in TMD discs of humans.  相似文献   

44.
A wide variety of malignant renal and urinary bladder diseases can be detected on 18F-FDG PET/CT. Although the PET/CT findings are often nonspecific, the aim of this atlas was to demonstrate that the spectrum of renal and urinary bladder malignancy that can be evaluated with PET/CT is much broader than current medical literature would suggest. PET/CT readers and oncologists should be aware of the variety of urological tumor types that can be detected on PET/CT and some of the patterns of 18F-FDG uptake that can be observed in these cases.  相似文献   
45.
The study of eye behavior is of paramount importance in the differential diagnosis of disorders of consciousness (DoC). In spite of this, assessment of eye movement patterns in patients with vegetative state (VS) or minimally conscious state (MCS) only relies on clinical evaluation. In this study we aimed to provide a quantitative assessment of visual tracking behavior in response to moving stimuli in DoC patients. Nine VS patients and nine MCS patients were recruited in a Neurorehabilitation Unit for patients with chronic DoC; 11 matched healthy subjects were tested as the control group. All participants underwent a quantitative evaluation of eye-tracking pattern by means of a computerized infrared eye-tracker system; stimuli were represented by a red circle or a small color picture slowly moving on a PC monitor. The proportion of on- or off-target fixations differed significantly between MCS and VS. Most importantly, the distribution of fixations on or off the target in all VS patients was at or below the chance level, whereas in the MCS group seven out of nine patients showed a proportion of on-target fixations significantly higher than the chance level. Fixation length did not differ among the three groups significantly. The present quantitative assessment of visual behaviour in a tracking task demonstrated that MCS and VS patients differ in the proportion of on-target fixations. These results could have important clinical implications since the quantitative analysis of visual behavior might provide additional elements in the differential diagnosis of DoC.  相似文献   
46.
Abstract:  This study presents nationally representative trends (1998–2004) and patterns in skin cancer risk behaviors, including sunburns, sun protection, and indoor tanning behaviors, and attitudes regarding ultraviolet radiation exposure among parents of U.S. adolescents. Data were from the American Cancer Society Sun Surveys I and II, telephone-based random digit dialed cross-sectional surveys of U.S. adolescents and their parents conducted in the summers of 1998 and 2004. Between 1998 and 2004, use of sunscreen, wide-brimmed hats and composite use of three to five behaviors increased significantly; concurrently, indoor tanning use increased significantly and sunburn prevalence changed a little. In 2004, 47% reported summer sunburns and more than half of those received painful sunburns. Parents continued to report low compliance with recommended behaviors; sunscreen use was most frequently reported, but many followed inappropriate application practices. About 13% practiced indoor tanning in the past year. Parents reported high levels of positive attitudes toward sun protection benefit, but at the same time, significant proportions reported positive tan appeal and outdoor sun exposure attitudes. The low rates and mixed progress in safe ultraviolet radiation exposure behaviors demand more attention for primary skin cancer prevention among parents of adolescents that focuses on changing beliefs about tanning appeal and promotes comprehensive ultraviolet radiation exposure protection.  相似文献   
47.
Objective.?The aim of the study was to investigate the impact of the climacterium (before and after menopause) on platelet activation.

Background.?Platelet activation has been associated to the risk of cardiovascular disease. There is much speculation about the relationship between platelet function and sex steroids, due to peculiarities of platelet action between the genders, including concerns about the influence of low estradiol status in menopausal women.

Methods.?By means of a cross-sectional study design, 37 female patients divided into two groups were compared. Group A consisted of ten women, mean age 43.9 years, in the premenopausal period, with normal estrogen levels; and Group B comprised 27 patients, mean age 53.0 years, who had all reached menopause. Platelet activation markers, namely P-selectin and glycoprotein IIb–IIIa complex (GPIIb–IIIa), were evaluated by flow cytometry with monoclonal antibodies. A binding index was calculated for both parameters (percentage of positive platelets?×?mean fluorescence of positive platelets). Also, thromboxane A2 was quantified by means of its main plasma metabolite, thromboxane B2, by enzyme immunoassay.

Results.?P-selectin and GPIIb–IIIa expression results revealed lower platelet activation status after menopause, as there was a decrease in both the percentage of P-selectin?+? platelets and of GPIIb–IIIa mean fluorescence of positive platelets, lowering both binding indices. P-selectin binding index differed significantly between Group A (12.3?±?3, n?=?10) and Group B (6.2?±?2.9, n?=?27; mean?±?standard deviation (SD), p?<?0.001). GPIIb–IIIa binding index also differed significantly between both groups (Group A: 18.8?±?2.3, n?=?10 vs. Group B: 16.2?±?3.1, n?=?27; mean?±?SD, p?<?0.0018). Plasma concentration of thromboxane B2 was 1.07?±?0.5?pg/well before menopause (Group A, n?=?10) and 1.9?±?4.1?pg/well after menopause (Group B, n?=?27), not significantly different (mean?±?SD, baseline?×?therapy, p?=?0.85).

Conclusions.?After the menopause, climacteric women – whose estradiol status is low – have a decreased activation platelet status compared with premenopausal women. Nevertheless, further studies on a larger sample are necessary for conclusive data regarding cardiovascular disease.  相似文献   
48.
PURPOSE: To retrospectively correlate high-risk proliferative breast lesions (radial scar, atypical lobular hyperplasia, lobular carcinoma in situ and papillary lesions) diagnosed on core biopsy with the definitive histopathological diagnosis obtained after surgical excision or with the follow-up, in order to assess the role of core biopsy in such lesions. To discuss the management of the patient after a core biopsy diagnosis of high-risk proliferative breast lesion. MATERIAL AND METHODS: We evaluated 74 out of 1776 core biopsies consecutively performed on 67 patients. The histopathologic findings were as follows: 11 radial scars (RS), 3 atypical lobular hyperplasias (ALH), 3 lobular carcinomas in situ (LCIS), 57 benign papillary lesions. All patients underwent bilateral mammography, whole-breast ultrasound with a linear-array broadband transducer, and core biopsy with a 14 Gauge needle and a mean number of samples of 5 (range 4-7). Sixty-two of 67 patients, for a total of 69/74 lesions, underwent surgical biopsy despite benign histopathologic findings, mostly because of highly suspicious imaging for malignancy (BIRADS 4-5), whereas 5 patients refused surgery and have been followed up for a least 18 months and are still being followed up (2 with RS, 1 with ADH and 2 with papillary lesions). RESULTS: Among the core biopsied lesions with a diagnosis of RS (n = 11) pathology revealed one ductal carcinoma in situ (DCIS) (this case was characterized by granular microcalcifications on mammography and by a mass with irregular margins on ultrasound). Also in the group of ADH (n = 3) pathology revealed one DCIS (lesion not visible on mammography but depicted as a suspicious mass on US). In the group of LCIS (n = 3) pathologists found an invasive lobular carcinoma (ILC). Among the benign papillary lesions (n = 57) histopathologic analysis of the surgical specimen revealed 7 malignant lesions (4 papillary carcinomas and 3 DCIS), whose mammographic and ultrasound findings were indistinguishable from benign lesions. Altogether there were 10 false negative results (underestimation) out of 74 core biopsies with a diagnosis of high-risk proliferative breast lesions. CONCLUSION: The high rate of histological underestimation after core biopsy (10/74) (13.5%) demands a very careful management of patents with a core biopsy diagnosis of high-risk proliferative breast lesions, especially in the case of RS, lobular neoplasia and papillary lesions. However, the high imaging suspicion for malignancy prompts surgery. It is possible to assume that, when there is a low imaging suspicion for malignancy, when enough tissue has been sampled for pathology and no atypia is found within the lesions, surgery is not mandatory but a very careful follow-up is recommended. We must underline that there is no agreement regarding the quantity of tissue to sample. Vacuum-assisted biopsy may lead to better results, although there is as yet no proof that it can actually replace surgery in this group of lesions, since it seems only to reduce but not abolish the histological underestimation.  相似文献   
49.
Abstract

Personal characteristics, developmental influences, and therapy practices of nine peer-nominated expert psychotherapists practicing in the diverse country of Singapore were identified using qualitative methods. Sixteen themes were organized within four categories: (a) personal characteristics (empathic, nonjudgmental, respectful); (b) developmental influences (experience, self-awareness, humility, self-doubt); (c) approach to practice (balance between support and challenge, flexible therapeutic stance, empowerment/strength-based approach, primacy of the therapeutic alliance, comfortable addressing spirituality, embraces working within a multicultural context); and (d) ongoing professional growth (professional development practices, benefits of teaching/training others, challenges to professional development in Singapore). Cross-cultural comparisons between this study and Jennings and Skovholt's (1999) study of Minnesota expert psychotherapists found considerable overlap of themes. Implications for research and practice of psychotherapy are offered.  相似文献   
50.
J Oral Pathol Med (2011) 40 : 587–592 Lubricin is a chondroprotective, mucinous glycoprotein which contribute to joint lubrication, especially to boundary lubrication and maintains joint integrity. The present investigation aimed to study the immunolocalization of lubricin in TMJ discs from patients affected by anterior disc displacement with reduction (ADDwR) ADDwoR. Eighteen TMJ displaced disc affected by ADDwoR were processed immunohistochemically, with a polyclonal anti‐lubricin antibody, used at 1:50 working dilution. The percentage of lubricin immunopositive cells (extent score = ES) and the extent of lubricin staining of the disc extracellular matrix (ECM), were evaluated. Each sample was scored for histopathological changes. Percentage of immunostained surface disc cells was the same (ES = 4) in both control and ADDwOR cells, being this data not statistically significant (P < 0.05). In pathological specimens the percentages of lubricin‐stained cells was very high with an ES of 4 respect to control specimen, and this difference was statistically significant different (P > 0.05). The extracellular matrix (ECM) of discs at the disc surfaces of both pathological and normal specimens was very heavily stained (++++). Both the ES and ECM staining were not statistically correlated to the TMJ degeneration score according to the Spearman’s rank correlation coefficient. According to our findings, a longstanding TMJ disc injury, affects lubricin expression in the TMJ disc tissue and not its surfaces, moreover, lubricin immunostaining is not correlated to TMJ disc histopathological changes.  相似文献   
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