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61.
In recent years, websites that stress the message of thinness as the ideal and only choice have surfaced on the internet. The possibility that pro-anorexia websites may reinforce restrictive eating and exercise behaviors is an area of concern. In addition, friends may be influencing one another to view these websites, further contributing to drive for thinness in women and drive for muscularity in men. Three hundred male and female undergraduate psychology students responded to questionnaires assessing: internalization of pro-anorexia website content, internalization of general media content, influence of friends to view pro-anorexia websites, peer influence, drive for muscularity, and drive for thinness. Results showed internalization of pro-anorexia website content was positively correlated with drive for thinness in women, and negatively correlated with drive for muscularity in men. Internalization of pro-anorexia website content was found to be related to both drive for thinness in women and drive for muscularity in men.  相似文献   
62.
There is as yet no consensus for considering pure acute sensory ataxic neuropathy (ASAN) as a variant of Guillain-Barré syndrome (GBS). Reactivity against gangliosides sharing disialosyl epitopes has been reported in these patients. The aim of this study was to determine the spectrum of reactivity against gangliosides in ASAN and to define the clinical pattern. From our database we identified patients with suspicion of ASAN. We defined ASAN as the presence of ataxia of peripheral origin with loss of proprioception, and areflexia, absence of ophthalmoplegia and no or minimal muscle weakness. Patients who met these criteria were retrospectively reviewed for their spectrum of reactivity against gangliosides and clinical features. We identified 12 patients fulfilling pre-defined criteria for ASAN. Reactivity against gangliosides containing disialosyl epitopes was present in seven patients. Concomitant reactivity against other gangliosides was present in 6/7 patients. All patients presented good prognosis and an antecedent illness was present in nine. Our results support the previously described clinico-immunological association between ASAN and disialosyl specificity, and widen the spectrum of reactivity against gangliosides. The acute presentation with a monophasic course, and good prognosis in all cases, together with transient immunoglobulin G antiganglioside antibodies and infectious antecedent in 7/12 patients support the inclusion of ASAN as a GBS variant.  相似文献   
63.
BACKGROUND: In nonimmediate cutaneous reactions to drugs, the skin is the organ most frequently involved, and T cells may play a relevant role. T cells related to skin immune responses express the cutaneous lymphocyte-associated antigen (CLA), the skin-homing receptor. METHODS: We studied the expression of the CLA in peripheral blood T cells from nine subjects with exanthematous reactions induced by beta-lactams (4), phenytoin (2), propyphenazone (1), spiramycin plus metronidazol (1), and captopril plus tiazide (1). The cutaneous symptoms appeared at least 6 h after drug intake. CLA expression was evaluated by flow cytometry at the time of the reaction (T1) and 1 month later (T2). HLA-DR activation marker expression was also evaluated at T1. In four patients, it was necessary to readminister the culprit drug to establish a causal relationship, and sequential estimation of the markers was performed. Two control groups were included: healthy controls and subjects exposed to the culprit drugs with good tolerance. Values were compared by nonparametric statistics. RESULTS: The expression of circulating CLA + T cells at T1 was increased compared to healthy controls (median = 20.4 vs 9.4) (P < 0.001), and the patients also expressed increased levels of HLA-DR (median = 3.8) (P < 0.005). Comparison between T1 and T2 (median = 11.2) also showed differences in levels of CLA+ T cells (P < 0.01). The patients re-exposed to the culprit drug showed an increase followed by a decrease of circulating CLA+ T cells (P < 0.05) and CLA+ HLA-DR+ (P < 0.05) paralleling the symptoms. CONCLUSIONS: These data support the immunologic nature of delayed skin reactions to drugs, and suggest that these CLA+ T cells parallel the disease evolution and may participate in the pathophysiologic mechanisms.  相似文献   
64.
The influence of two different carriers, poly-L-lysine (PLL) and human serum albumin (HSA) in the binding of specific IgE antibodies to the benzyl penicilloyl hapten (BPO) was determined in a solid-phase assay. Serum samples from patients with a history of immediate reaction to penicillin and which had shown the presence of IgE antibodies to BPO were used. Benzyl penicilloyl derivatized cellulose discs were prepared using PLL of different molecular weight and HSA as carriers. These were treated with different molar ratios of benzyl penicillin. These reagents were compared for uptake of BPO-specific IgE using a pool of sera in a radioallergosorbent test (RAST) type assay. Two PLL systems and two HSA systems were finally compared using 26 individual sera. RAST values were compared by Kruskal-Wallis and Wilcoxon tests. The relationships between the four different assays were evaluated by determining Pearson correlation coefficients and the concordance by determining intraclass correlation coefficients (ICC). Analysis of means by the Wilcoxon test revealed significant differences (P less than 0.01) only when the different carrier assays were compared. The correlation coefficients between all the assays were significant (P less than 0.0001), but the ICC was low when the different carrier assays were compared. These results indicate that the nature of the carriers studied (PLL and HSA) influences the capacity for binding IgE antibodies in the RAST procedure. The differences observed indicate that one conjugate cannot be substituted for the other in the determination of IgE antibodies to BPO and that BPO-PLL is preferable.  相似文献   
65.
Introduction The Government of Angola is engaged in ongoing efforts to increase access to contraceptives, in particular contraceptive implants (CIs). Discontinuation of CIs, however, has been identified as being a challenge to this work, hindering the improvement of contraceptive prevalence, and in turn, maternal and child health. The objective of this study was to understand motives for contraceptive implant discontinuation in Luanda and Huambo, Angola. Methods We conducted 45 in-depth interviews and six focus groups amongst former and current contraceptive implant clients and family planning nurses in eight clinics across the provinces of Huambo and Luanda. Data collectors transcribed and translated key information from Portuguese into English. We used a combined deductive/inductive approach to code and analyze data. Results Participants described adverse side effects, desire for pregnancy, partner dissatisfaction, quality of care, alternative or lack of information, and religion as motives for discontinuation. Adverse side effects, including prolonged bleeding, amenorrhea, and headaches were most commonly cited by both clients and providers. Discussion Motives for discontinuation reflect existing findings from other studies in similar settings, in particular the influence of adverse side effects and desire for pregnancy as motivating factors. We contextualize these findings in the Angolan setting to tease out the relationship between cultural norms of ideal family size and the perceived role of women in regards to fertility and child-bearing. We suggest that programs enter into dialog with communities to address these concerns, rather than working exclusively on improving service delivery and quality.  相似文献   
66.
67.
Uros people live in floating reed islands in Titikaka Lake in front of Puno town (Peru). They could have started Tiwanaku culture and shared genes and culture with Pacific Islanders; it is particularly relevant the giant hat covered men statues found in both Tiwanaku at Titikaka Lake shore and Easter Island (3700 km far from Chile in Pacific Ocean). These giants monoliths are very similar one another and unique in America and Pacific Islands. The following HLA alleles are shared in a specifically high frequency between Uros and Pacific Islanders : HLA-A*24:02, HLA-B*35:05, HLA-B*48:01, HLA-DRB1*04:03, HLA-DRB1*08:02 and HLA-DRB1*09:01. Uros also have 3 unique HLA haplotypes: A*24:02-B*15:04 ? DRB1*14:02-DQB1*03:01, A*68:01:02-B*35:05-DRB1*04:03-DQB1*03:02, A*24:02-B*48:01-DRB1*04:03-DQB1*03:02. Also Uros seem to be one of the most ancient population in Titikaka Lake that could have started Tiwanaku culture. Prehistoric contacts between Amerindians and Pacific Islanders are strongly suggested by genetic and cultural traits. It is not discarded that Uros could have come from Pacific Islands: Uros show melanic skin and are dolichocephalic; in contrast, surrounding Aymara people have a clear skin and are brachicephalic. The Kon-Tiki project led by Thor Heyerdahl showed that a simple sailing is possible between Peru and Polynesia Islands; also, the most ancient skull found in America is of black origin: Luzia, suggesting that first America peopling was also carried out by Black/coloured people.  相似文献   
68.
Hypersensitivity pneumonitis (HP) is a lung inflammatory disease caused by the inhalation of a variety of antigens. Previous studies support the role of the major histocompatibility complex (MHC) class II genes in the susceptibility to develop HP. However, the putative role of other MHC loci has not been elucidated. Transporters associated with antigen processing (TAP) genes are located within the MHC class II region and play an important role transporting peptides across the endoplasmic reticulum membrane for MHC class I molecules assembly. The distribution of single nucleotide polymorphisms (SNPs) in TAP1 genes was analyzed in 73 hypersensitivity pneumonitis (HP) patients and 58 normal subjects. We found a significant association of the allele Gly-637 (GGC) (p=0.00004, OR=27.30, CI=3.87-548.04) and the genotypes Asp-637/Gly-637 (p=0.01, OR=16.0, CI=2.19-631.21), Pro-661/Pro-661 (p=0.006, OR=11.30, CI=2.28-75.77) with HP. A significant decrease in the frequency of the allele Pro-661 (CCA) (p=0.008, OR=0.06, CI=0-0.45), the genotype Asp-637/Asp-637 (p=0.01, OR=0.17, 95% CI=0.05-0.58) and the haplotype [Val-333 (GTC), Val-458 (GTG), Gly-637 (GGC), Pro-661 (CCA)] was detected in HP patients compared with controls (p=0.002, OR=0.07, CI=0.0-0.57). These findings suggest that TAP1 gene polymorphisms are related to HP risk, and highlight the importance of the MHC in the development of this disease.  相似文献   
69.
The effect of alcohol consumption before puberty on the development of genital-grooming (GG) and on the onset of sexual behavior was assessed. Wistar male rats were continuously exposed in a one-bottle access situation to either 6% ethanol (alcohol group, AG), an isocaloric sweetened solution (vehicle group, VG) or were maintained in standard laboratory conditions (control group, CG). Each solution was the only available liquid in each group from weaning (22 days) to 40 days of age. GG behavior was recorded from 25 to 47 days of age and sexual behavior was recorded from 42 to 74 days of age. The age at the maximum peak of both frequency and duration of GG showed an advance in the AG (33-35 days of age) compared with the CG (45 days) and the VG (47 days). An advance in the onset of sexual behavior was observed in the AG: at 46 days of age, seven of the nine males of this group showed ejaculatory behavior. In contrast, in the CG and VG, ejaculation occurred in at least 50% of subjects after 58 days of age. Regardless of the advance in the onset of sexual behavior, the characteristics of the different parameters of the copulatory sequence were not impaired by alcohol. The apparent advance in the onset of puberty is discussed in terms of the opioid hypothalamic activity as a mechanism that affects the LH secretion.  相似文献   
70.
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