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931.

Purpose

Heat-shock proteins (HSPs) or antibodies against them may contribute to glaucomatous optic neuropathy. We investigated the associations of HSP70-1 polymorphisms with open-angle glaucoma (OAG) in a Japanese population.

Methods

In 241 normal Japanese controls and 501 Japanese OAG patients, including 211 with primary open-angle glaucoma (POAG) and 290 with normal-tension glaucoma (NTG), two single-nucleotide polymorphisms, A?110C and G+190C, of HSP70-1 were identified by using an Invader assay and polymerase chain reaction-restriction fragment length polymorphism, respectively. Genotype distributions were compared between controls and OAG patients. Age at diagnosis, untreated maximum intraocular pressure, and visual field defects at diagnosis were examined for associations with the polymorphisms.

Results

Distribution of the A?110C genotype (AA versus AC+CC) differed significantly between controls and OAG patients (P = 0.007), POAG patients (P = 0.007), or NTG patients (P = 0.032). The genotype distribution of the G+190C polymorphism did not differ significantly between the controls and any patient group. No significant differences in the clinical characteristics of the patients were detected between genotype-defined groups by logistic regression analysis.

Conclusion

The A?110C polymorphism of HSP70-1 may be associated with OAG pathogenesis in Japanese patients.?Jpn J Ophthalmol 2007;51:417–423 © Japanese Ophthalmological Society 2007
  相似文献   
932.
PURPOSE: To investigate the mechanism of cell death in laser-induced choroidal neovascularization (CNV) after photodynamic therapy (PDT). METHODS: PDT was performed in Brown-Norway rats using laser light at a wavelength of 689 nm, irradiance of 600 mW/cm(2), and fluence of 25 J/cm(2) after intravenous injection of verteporfin at the doses of 3, 6, and 12 mg/m(2). Apoptotic cells in CNV were detected by TUNEL assay at 1, 3, 6, 15, 24, and 48 hours after PDT. Caspase activation at 1, 3, 6, 15, and 24 hours after PDT was determined by immunohistochemistry (IHC) with a cleaved caspase-3 or -9 antibody. Akt activity was determined by Western blot and IHC with a phosphorylated-Akt (pAkt) antibody. To investigate the roles of Akt in PDT-induced apoptosis, insulin-like growth factor (IGF)-1, an Akt activator, with or without wortmannin, an inhibitor of PI3K-Akt pathway, was injected into the vitreous before PDT. RESULTS: The number of TUNEL-positive cells in CNV increased at 3 hours after PDT and peaked at 6 hours, showing a dose dependence of verteporfin. Caspase activation was detected in TUNEL-positive cells. Dephosphorylation of Akt in CNV occurred within 1 hour. IGF-1 significantly activated Akt and suppressed the number of TUNEL-positive cells in CNV, and the effects of IGF-1 were diminished by wortmannin. CONCLUSIONS: PDT induced caspase-dependent apoptosis in CNV. These results suggest that PDT leads to dephosphorylation of Akt and subsequent activation of the caspase-dependent pathway. Understanding the intracellular signaling mechanisms of apoptosis in PDT may lead to more selective and effective treatment of CNV secondary to age-related macular degeneration.  相似文献   
933.
934.
The risk of hepatocellular carcinoma (HCC) increases with the severity of hepatic inflammation. Interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha are proinflammatory cytokines with multiple biological effects and may play essential roles in inflammation-linked tumor development. We conducted a case-control study including 209 incident HCC cases and two control groups (275 hospital controls and 381 patients with chronic liver disease [CLD] without HCC) to investigate whether IL-1B and TNF-A gene polymorphisms influence HCC susceptibility with any interaction with alcohol and tobacco. By comparing HCC cases with CLD patients, we found that IL-1B -31T/C polymorphism was associated with HCC risk among never drinkers and current smokers; adjusted odds ratios (and 95% confidence intervals) for C/T and T/T genotypes compared with C/C genotype were 1.70 (0.76-3.77) and 2.46 (1.05-5.76) (P trend=0.03), respectively, among never drinkers, and 1.53 (0.60-3.99) and 2.54 (0.81-7.95) (P trend=0.11), respectively, among current smokers. Similarly, HCC risk associated with heavy alcohol intake and current smoking differed by this polymorphism among CLD patients. IL-1B -31T/C polymorphism may modify HCC risk in relation to alcohol intake or smoking.  相似文献   
935.
936.
Hokoei-to (pugongying-tang) is one of the Kampo formulae clinically used for gynecological disturbances such as lack of lactation and mammary swelling. We investigated the effect of hokoei-to on the nervous and immune systems in ovariectomized mice as a climacteric disorder model. Hokoei-to suppressed the decrease of monoamines in the ventral hippocampus and dorsal hippocampus of ovariectomized mice. It was shown that the hokoei-to could improve the metabolic turnover of dopamine. The mitogenic activity of lymphocytes in the spleen was reduced after ovariectomy; a suppression of this reduced activity was observed in the group given hokoei-to.  相似文献   
937.

Background

Evidence suggests that Ser326Cys, a genetic polymorphism of human 8-oxoguanine glycosylase 1 (hOGG1), is associated with insulin resistance and type 2 diabetes; however, the underlying mechanism is unclear. Recently, an animal study showed a significant association between the hOGG1 genotype and obesity, although evidence for such an association in humans is limited. The purpose of this study was to examine the association between the hOGG1 genotype and body mass index (BMI) and fasting blood glucose (FBG) levels.

Methods

Cross-sectional analysis was conducted using the baseline survey data from a Japan Multi-Institutional Collaborative Cohort Study, which included 1793 participants aged 40–69 years. The hOGG1 polymorphism was detected using a multiplex polymerase chain reaction-based invader assay. Multiple linear regression, analysis of covariance, and logistic regression were used to control for confounding variables.

Results

The Cys allele was significantly associated with increased BMI, FBG level, and total cholesterol (TC) level, even after adjustment for gender, age, energy intake, alcohol, smoking, physical activity, and family history of diabetes. An association with BMI was still observed after further adjustment for FBG and TC, but not for the study area (Amami or the mainland). The Cys/Cys genotype was significantly more prevalent in the participants with higher BMI (>27.5 kg/m2). However, the impact of genotype decreased and significance disappeared after adjusting for the study area.

Conclusions

The present results suggest that the study area being inside Japan confounds the association between hOGG1 genotype and obesity.Key words: human 8-oxoguanine glycosylase 1 (hOGG1), obesity, body mass index (BMI), fasting blood glucose (FBG), polymorphism, study area  相似文献   
938.
During the coronavirus disease 2019 (COVID-19) pandemic, autopsies have provided valuable insights into the pathogenesis of COVID-19. The precise effect of this pandemic on autopsy procedures in Japan, especially in instances unrelated to COVID-19, has not yet been established. Therefore, we conducted a questionnaire survey from December 2020 to January 2021 regarding the status of pathological autopsy practices in Japan during the first year of the COVID-19 pandemic. The questionnaire was sent to 678 medical facilities with pathologists, of which 227 responded. In cases where a confirmed diagnosis of COVID-19 was not made at the time of autopsy, many facilities counted them as suspected COVID-19 cases if pneumonia was suspected clinically. At around half of the sites, autopsies were prohibited for suspected COVID-19 cases. In addition, the number of autopsies of non-COVID-19 cases during the pandemic period was also investigated, and a significant decrease was observed compared with the incidence in the pre-pandemic period. The COVID-19 pandemic has affected not only the autopsies of COVID-19 cases but also the entire practice of pathological autopsies. It is necessary to establish a system that supports the implementation of pathological autopsy practices during the pandemic of an emerging infectious disease.  相似文献   
939.

Background:

Pancreatitis is the most common and serious complication to occur after endoscopic retrograde cholangiopancreatography (ERCP). It is often associated with additional diagnostic modalities and/or treatment of obstructive jaundice. The aim of this study was to determine the risk of post-ERCP pancreatitis associated with pancreaticobiliary examination and endoscopic biliary drainage (EBD).

Methods:

A total of 740 consecutive ERCP procedures performed in 477 patients were analysed for the occurrence of pancreatitis. These included 470 EBD procedures and 167 procedures to further evaluate the pancreaticobiliary tract using brush cytology and/or biopsy, intraductal ultrasound and/or peroral cholangioscopy or peroral pancreatoscopy. The occurrence of post-ERCP pancreatitis was analysed retrospectively.

Results:

The overall incidence of post-ERCP pancreatitis was 3.9% (29 of 740 procedures). The risk factors for post-ERCP pancreatitis were: being female (6.5%; odds ratio [OR] 2.5, P= 0.02); first EBD procedure without endoscopic sphincterotomy (ES) (6.9%; OR 3.0, P= 0.003), and performing additional diagnostic procedures on the pancreatobiliary duct (9.6%; OR 4.6, P < 0.0001). Pancreatitis after subsequent draining procedures was rare (0.4%; OR for first-time drainage 16.6, P= 0.0003). Furthermore, pancreatitis was not recognized in 59 patients who underwent ES. Seven patients with post-EBD pancreatitis were treated with additional ES.

Conclusions:

Invasive diagnostic examinations of the pancreaticobiliary duct and first-time perampullary biliary drainage without ES were high-risk factors for post-ERCP pancreatitis. Endoscopic sphincterotomy may be of use to prevent post-EBD pancreatitis.  相似文献   
940.
Tetrahydrobiopterin (BH4) is an essential co-factor for nitric oxide (NO) synthase (NOS) and regulates the production of NO, or endothelium-derived relaxation factor. Although NOS is highly expressed in the placenta and NO plays a critical role in the regulation of feto-placental circulation, the mechanism maintaining the level of BH4 is not known. To investigate the de novo synthesis of BH4 in the human placenta, the activity of guanosine triphosphate cyclohydrolase I (GTPCH), 6-pyruvoyltetrahydropterin synthase (PTPS), and sepiapterin reductase (SR) in the chorionic tissue during the first, second and third trimester of pregnancy was analyzed. GTPCH activity was the lowest of the three enzymes and became negligible after the second trimester. There was no significant change in PTPS activity throughout pregnancy. Although SR activity decreased significantly after the second trimester, the levels remained abundant throughout pregnancy. These results showed that GTPCH is a rate-limiting enzyme and the total activity of the de novo synthesis of BH4 is negligible in the mature placenta after the second trimester when fetal growth is accelerated. The present study suggests that the level of BH4 in the placenta depends principally on the system other than de novo synthesis. The salvage pathway is considered the most potent system, which is formed by the transfer of the substrates from the fetus and their enzymatic conversion to BH4 in the placenta.  相似文献   
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