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71.
Background: The female liver is more sensitive to the toxic effect of chronic alcohol intake than the male liver. The aim of the study was to compare the influence of gender and sex hormonal status on apoptosis and cell proliferation following chronic ethanol intake.
Methods: Male and female rats were pair fed for 8 weeks a liquid diet containing 36% of their total daily calories as ethanol (ETOH group) or sucrose (control group). Liver samples were analyzed for apoptosis and hepatocyte proliferation by immunohistochemistry. The hepatic production of factors able to influence cell death and proliferation, such as tumor necrosis factor alpha (TNFα) and interleukin 6 (IL-6) were determined.
Results: In both male and female rats, ethanol intake promoted apoptosis in the liver. This effect of ethanol was more evident in female than male rat livers. Hepatic TNFα levels, which promote apoptosis, are significantly more elevated in female than in male livers. Hepatic IL-6 production, which promotes hepatocyte proliferation, was induced by ethanol only in males, but not female animals.
Conclusion: This observed difference in cytokine responses may contribute to the enhanced sensitivity of female liver to EtOH-induced injury.  相似文献   
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73.
IntroductionGender dysphoria (GD) is a condition in which the individual's gender identity does not correspond to their biological sex, causing significant distress. Biological males who identify as females are referred to as transgender females or as showing male-to-female GD (MtF GD) and biological females who identify as males are referred to as transgender males or as showing female-to-male GD (FtM GD). In our center, there is a multidisciplinary consultation to approach and follow patients with GD.AimWe aimed to analyze the characteristics of the individuals who attend this consultation.MethodsRetrospective study of individuals attending the Sexual Medicine Group Consultation. Age, comorbidities, symptom onset, and hormonal and surgical treatment were analyzed.ResultsIn total, 114 patients were diagnosed with GD: 68.4% FtM GD and 31.6% MtF GD. Median age was 30.2 ± 12 years. Among the patients, 63.2% reported symptom onset in childhood: 14.9% between 10 and 18 years, and 4.4% later than 18 years. Median age at treatment initiation was 23.1 ± 7.1 years. Several individuals had concomitant medical conditions, notably smoking (n = 37; 32.5%) and depression (n = 26; 22.3%). The majority of (92.3% FtM GD and 88.9% MtF GD) were under hormone treatment, and about one-third had undergone some sex reassignment surgery.DiscussionWe found higher prevalence of FtM than MtF, in contrast with most other studies. The reasons for this are not clear. A high percentage of our patients were self-medicated. Other characteristics were similar to those previously reported.ConclusionMedical requests by individuals with GD are increasing worldwide. To our knowledge, this is the first study to portray a case series in a consultation center dedicated to the diagnosis, treatment and follow-up of individuals with GD in Portugal.  相似文献   
74.
Neurons and glia arise from neural progenitor cells that express nestin. Although substantial changes in neuronal development were observed during the postnatal period, data concerning dynamics of nestin expression in the superior cervical ganglia (SCG) of rat during that period are lacking. It is known that gonadectomy and steroid hormones influence the development of neurons in the SCG during the postnatal period, but there are no data on how they influence the persistence of nestin expression in the SCG cells.The dynamics of nestin expression in the SCG in rats of three age groups, as well as the influence of gender and gonadectomy, was investigated.Three groups of male rats were sacrificed at 2, 3 and 6 months of age. Additional groups of male and female Sprague-Dawley rats were gonadectomized at the age of 2 months. After 30 days, they were sacrificed and SCGs were harvested and processed immunohistochemically. Immunoreactivity for nestin in the SCG was observed in satellite glia, based on their expression of s100. The proportion of neurons that were encircled with nestin-immunoreactive satellite cells (nestin encircled neurons, NEN) decreased between second and third month of age (p < 0.05). The proportion of NEN was greater in the NPY+ than in the NPY− subpopulation. The proportion of NEN in the SCG of female rats was significantly higher (p < 0.05) than that of both, the male rats and ovariectomised groups. The percentage of these neurons was significantly higher (p < 0.05) in orchidectomised, in comparison to male rats.Results show the existence of nestin-immunoreactive satellite cells in the SCG of adult rats. A substantial decrease of nestin expression in SCG cells of rats, after the onset of sexual maturation, was observed. This decrease showed significant sex-dependence and was dramatically influenced by gonadal activity.  相似文献   
75.
Radiology report errors occur for many reasons including the use of pre-filled report templates, wrong-word substitution, nonsensical phrases, and missing words. Reports may also contain clinical errors that are not specific to the speech recognition including wrong laterality and gender-specific discrepancies. Our goal was to create a custom algorithm to detect potential gender and laterality mismatch errors and to notify the interpreting radiologists for rapid correction. A JavaScript algorithm was devised to flag gender and laterality mismatch errors by searching the text of the report for keywords and comparing them to parameters within the study’s HL7 metadata (i.e., procedure type, patient sex). The error detection algorithm was retrospectively applied to 82,353 reports 4 months prior to its development and then prospectively to 309,304 reports 15 months after implementation. Flagged reports were reviewed individually by two radiologists for a true gender or laterality error and to determine if the errors were ultimately corrected. There was significant improvement in the number of flagged reports (pre, 198/82,353 [0.24 %]; post, 628/309,304 [0.20 %]; P = 0.04) and reports containing confirmed gender or laterality errors (pre, 116/82,353 [0.014 %]; post, 285/309,304 [0.09 %]; P < 0.0001) after implementing our error notification system. The number of flagged reports containing an error that were ultimately corrected improved dramatically after implementing the notification system (pre, 17/116 [15 %]; post, 239/285 [84 %]; P < 0.0001). We developed a successful automated tool for detecting and notifying radiologists of potential gender and laterality errors, allowing for rapid report correction and reducing the overall rate of report errors.  相似文献   
76.
AIM: This study was designed to examine the hypothesis that gender differences in I/R injury are associated with endothelial cell nitric oxide synthase (eNOS)-derived nitric oxide (NO). METHODS: Wistar rats were randomized into seven experimental groups (12 animals per group). Except for the sham operated groups, all rats were subjected to total liver ischemia for 40 min followed by reperfusion. All experimental groups received different treatments 45 min before the laparotomy. For each group, half of the animals (six) were used to investigate the survival; blood samples and liver tissues were obtained in the remaining six animals after 3 h of reperfusion to assess serum NO, alanine aminotransferase (ALT) and TNF-α levels, liver tissue malondialdehyde (MDA) content, and severity of hepatic I/R injury. RESULTS: Basal serum NO levels in female sham operated (FS) group were nearly 1.5-fold of male sham operated (MS) group (66.7±11.0 μmol/L vs45.3μ10.1 μmol/L, P<0.01). Although serum NO levels decreased significantly after hepatic I/R (P<0.01, vs sham operated groups), they were still significantly higher in female rat (F) group than in male rat (M) group (47.8±8.6 μmol/L vs 23.8±4.7 μmol/L, P<0.01). Serum ALT and TNF-α levels, and liver tissue MDA content were significantly lower in F group than in M group (370.5±46.4 U/L, 0.99±0.11 μg/L and 0.57±0.10 μmol/g vs668.7±78.7 U/L, 1.71±0.18μg/L and 0.86±0.11 μmol/g, respectively, P<0.01). I/R induced significant injury to the liver both in M and F groups (P<0.01 vs sham operated groups). But the degree of hepatocyte injury was significantly milder in F group than in M group (P<0.05 and P<0.01). The median survival time was six days in F group and one day in M group. The overall survival rate was significantly higher in F group than in M group (P<0.05). When compared with male rats pretreated with saline (M group), pretreatment of male rats with 17-β-estradiol (E2) (M+E2 group) significantly increased serum NO levels and significantly decreased serum ALT and TNF-α levels, and liver tissue MDA content after I/R (P<0.01). The degree of hepatocyte injury was significantly decreased and the overall survival rate was significantly improved in M+E2 group than in M group (P<0.01 and P<0.05). The NOS inhibitor Nw-nitro-L-arginine methyl ester (L-NAME) treatment could completely abolish the protective effects of estrogen in both male and female rats. CONCLUSION: The protective effects afforded to female rats subjected to hepatic I/R are associated with eNOS-derived NO.  相似文献   
77.
We investigated whether the universal provision of long-term care (LTC) under Japan's public system has equalized its use across households with different socio-economic characteristics, with a special focus on the gender and marital status of primary caregivers, and income. We used repeated cross-sectional data from national household surveys (2001, 2004, 2007, and 2010) and conducted multiple logistic regression analyses to obtain odds ratios of caregiver and household characteristics for service use, adjusting for recipients’ characteristics. The results showed that the patterns of service use have been consistently determined by caregivers’ gender and marital status over the period despite demographic changes among caregivers. The gap in service use first narrowed, then widened again across income levels after the global economic recession. The results indicate that the traditional gender-bound norms and capacity constraints on households’ informal care provision remained influential on decisions over service use, even after the universal provision of formal care. To improve equality of service utilization, the universal LTC system needs to meet diversifying needs of caregivers/recipients and their households, by overcoming barriers related to gender norms and economic disparity.  相似文献   
78.
Adolescent substance use is a developmentally contingent social practice that is constituted within the routine social-environment of adolescents' lives. Few studies have examined peer networks, perceived activity space risk (risk of substance use at routine locations), and substance use. We examined the moderating influence of peer network characteristics on the relationship between perceived activity space risk and substance use among a sample of 250 urban adolescents. Significant interactions were found between peer networks and perceived activity space risk on tobacco and marijuana use, such that protective peer networks reduced the effect of activity place risk on substance use. A significant 3-way interaction was found on marijuana use indicating that gender moderated peer network's effect on activity space risk. Conditional effect analysis found that boys' peer networks moderated the effect of perceived activity space risk on marijuana use, whereas for girls, the effect of perceived activity space risk on marijuana use was not moderated by their peer networks. These findings could advance theoretical models to inform social–environmental research among adolescents.  相似文献   
79.
We investigated the influence of gender, comorbidity, drinking history, and age on the clinical manifestations of DSM-III alcohol abuse and/or dependence in men and women. The sample was drawn from the National Institute of Mental Health Epidemiologic Catchment Area study, a large-scale, multicenter survey to investigate psychiatric disorders in the community. The results showed that gender and comorbidity had independent effects on problem drinking after drinking history and age had been taken into account. Gender contributed to the age of onset of problem drinking and the rate of its development. Comorbidity, drinking history, and age contributed independently to its severity. The effects of these variables in this community sample paralleled those reported in treatment samples.  相似文献   
80.
Malaria is one of the most serious public health problems in the world. For the last few decades, numerous studies have focused on the potential links between environmental transformations (such as the expansion of irrigation) and malaria occurrence. Most of these studies have been based on relatively simple models outlining the interactions of the host-vector-parasite triad. In this paper, we investigate the links between the intensification of irrigated rice cultivation and malaria. In an attempt to complement biomedical and entomological approaches we propose a model that recognises the influence of human-vector contacts on transmission processes, but stresses the importance of taking into consideration socio-economic and cultural factors in the management of disease episodes, and how these can be affected by transformations of natural resource management strategies. Using a case study in Northern C?te d'Ivoire, we investigated the complex mechanisms by which agriculture-generated changes in ecosystems and socio-economic organisation influence disease risks and produce new scenarios in the management of disease. Our results show that the socio-economic transformation and gender repositioning induced, or facilitated, by the intensification of lowland irrigated rice cultivation influence the health care system for malaria in the study area. They lead to a reduction of the capacity of women to manage malaria episodes among children and influence their vulnerability to the disease. We argue that these elements contribute to higher malaria prevalence in villages involved in double cropping of rice annually.  相似文献   
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