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21.
In this study, we demonstrate that Porphyromonas gingivalis fimbriae use molecules of β2 integrin (CD11/CD18) on mouse peritoneal macrophages as cellular receptors and also show that the β chain (CD18) may play a functional role in signalling for the fimbria-induced expression of interleukin-1β (IL-1β) and tumor necrosis factor alpha (TNF-α) genes in the cells. Using a binding assay with 125I-labeled fimbriae, we observed that fimbrial binding to the macrophages was inhibited by treatment with CD11a, CD11b, CD11c, or CD18 antibody but not by that with CD29 antibody. Western blot assays showed that the fimbriae bound to molecules of β2 integrin (CD11/CD18) on the macrophages. Furthermore, Northern blot analyses showed that the fimbria-induced expression of IL-1β and TNF-α genes in the cells was inhibited strongly by CD18 antibody treatment and slightly by CD11a, CD11b, or CD11c antibody treatment. Interestingly, intracellular adhesion molecule 1 (ICAM-1), a ligand of CD11/CD18, inhibited fimbrial binding to the cells in a dose-dependent manner. In addition, ICAM-1 clearly inhibited the fimbria-induced expression of IL-1β and TNF-α genes in the cells. However, such inhibitory action was not observed with laminin treatment. These results suggest the importance of β2 integrin (CD11/CD18) as a cellular receptor of P. gingivalis fimbriae in the initiation stage of the pathogenic mechanism of the organism in periodontal disease.  相似文献   
22.
The prebiotic effect of high β-glucan barley (HGB) flour on the innate immune system of high-fat model mice was investigated. C57BL/6J male mice were fed a high-fat diet supplemented with HGB flour for 90 days. Secretory immunoglobulin A (sIgA) in the cecum and serum were analyzed by enzyme-linked immunosorbent assays (ELISA). Real-time PCR was used to determine mRNA expression levels of pro- and anti-inflammatory cytokines such as interleukin (IL)-10 and IL-6 in the ileum as well as the composition of the microbiota in the cecum. Concentrations of short-chain fatty acids (SCFAs) and organic acids were analyzed by GC/MS. Concentrations of sIgA in the cecum and serum were increased in the HGB group compared to the control. Gene expression levels of IL-10 and polymeric immunoglobulin receptor (pIgR) significantly increased in the HGB group. HGB intake increased the bacterial count of microbiota, such as Bifidobacterium and Lactobacillus. Concentrations of propionate and lactate in the cecum were increased in the HGB group, and a positive correlation was found between these organic acids and the IL-10 expression level. Our findings showed that HGB flour enhanced immune function such as IgA secretion and IL-10 expression, even when the immune system was deteriorated by a high-fat diet. Moreover, we found that HGB flour modulated the gut microbiota, which increased the concentration of SCFAs, thereby stimulating the immune system.  相似文献   
23.
Among the pathological sequelae of facial paralysis is a paralytic eye. Apart from the psychological and aesthetic deficits, facial paralysis if left untreated can lead to dryness, ulceration and eventual blindness. Although numerous restorative microsurgical approaches have been introduced to address the sequelae of this problem, complete restoration of function to denervated facial muscles remains elusive.Utilizing the rat model of facial paralysis the present research has as an objective to examine a dual treatment approach. Specifically, this study combined the current microsurgical treatment of the cross-facial nerve graft with local administration of insulin-like growth factor I (IGF-I).The efficacy of this combined approach (cross-facial nerve graft + IGF-I) was assessed in the following ways: (a) behavior measurement of the blink response and (b) histomorphometry light and electron microscopy of the entire nerve graft. These data will help provide insight into the restoration of facial muscle function after trauma and assist in the future development of more potent treatment strategies.7he local adnünistration of IGF-I (50 micro g/ml) to the cross-facial nerve graft was found to restore the blink response faster and to strengthen the degree of eye closure. Light microscopy examination revealed that IGF-I significantly enhanced axonal regeneration within a nerve graft (a 22% increase in the mean number of axons), and increased the mean nerve fiber diameter and myelin thickness. Electron microscopy assessment of the nerve grafts demonstrated that the IGF-I treated grafts possessed a greater density of microtubules, which were evenly distributed within the axoplasm.  相似文献   
24.
OBJECTIVE: In this study, the clinical usefulness of transition zone (TZ) volume (TZV) measured by transrectal ultrasonography (TRUS) was investigated as a new parameter for the preoperative prediction of the treatment efficacy of transurethral resection of the prostate (TURP). METHODS: Fifty-six men with symptomatic benign prostatic hyperplasia (BPH; age 68.6 +/- 9.7 years) underwent TURP and were evaluated based on ordinary BPH parameters such as the international prostatic symptom score (I-PSS), quality of life (QOL) score, peak urine flow and entire prostate volume (PV), as well as the new TZV parameters and calculation of the TZ index. Relative risks were adjusted simultaneously for potentially confounding variables by multiple logistic regression analysis after adjustment for age, QOL, I-PSS, Qmax and residual urine. RESULTS: The adjusted relative risk for TURP at a TZ index of 0.1 increased to 4.5 (95% confidence interval 2.3-8.78). In general, poor responses were observed in patients with less symptomatic scores or lower values prior to operation, but there was a weak correlation between treatment outcome and preoperative scores or values of ordinary parameters. The volume parameters of BPH and PV did not predict treatment efficacy preoperatively, but TZV and the TZ index correlated with the treatment efficacy of TURP. CONCLUSION: TZV and the TZ index seem to be useful new parameters in preoperative decision-making with regard to TURP.  相似文献   
25.
The interaction between [Arg8]-vasopressin and a vasopressin receptor antagonist, [d(CH2)5(1), O-Me-Tyr2, Arg8]-vasopressin, was examined in Hiroshima rats and normotensive control rats under pentobarbital anesthesia. [Arg8]-vasopressin dose-dependently increased the arterial pressure in both the Hiroshima and control rats, the pressor effect being greater in the Hiroshima rats. After the administration of a vasopressin antagonist (0.01 mg/kg), which by itself decreased arterial pressure only in the Hiroshima rats, the dose-response curve for [Arg8]-vasopressin was much more greatly shifted to the right in the control rats. These results indicate that with or without a vasopressin antagonist, the exogenous [Arg8]-vasopressin induced more powerful pressor actions in the Hiroshima rats compared to the control rats.  相似文献   
26.
Few studies have examined the association of alcohol consumption and cigarette smoking with colorectal cancer in Asian populations whose genetic susceptibility to these factors are different from Western populations. We investigated this association and the joint effect of these factors, and estimated the population-attributable fraction to clarify the public health impact on a Japanese population, based on a prospective study. We analyzed the 10-year (cohort I) and 7-year (cohort II) follow-up data of the Japan Public Health Center-based prospective study on cancer and cardiovascular disease, derived from 90,004 (42,540 male and 47,464 female) middle-aged and elderly Japanese. We identified 716 (457 in men and 259 in women) newly diagnosed cases of colorectal cancer. Both alcohol consumption and smoking were clearly associated with colorectal cancer in men, after adjusting for age, family history of colorectal cancer, body mass index, and physical exercise. Regular heavy drinking of 150 g/week or more of ethanol showed a statistically significant increased risk compared with nondrinkers: relative risks (RRs) were 1.4 [95% confidence interval (CI), 1.1-1.9] for 150-299 g/week and 2.1 (95% CI, 1.6-2.7) for 300 g/week or more. On the contrary, regular ethanol consumption was not associated with colorectal cancer (RR, 0.7; 95% CI, 0.4-1.1) in women. In terms of smoking, the RRs were 1.4 (95% CI, 1.1-1.8) for current smokers and 1.3 (95% CI, 0.98-1.7) for ex-smokers compared with never-smokers in men. The risk of smoking in women was similar to that in men, although not statistically significant. The colorectal cancer risk with 300 g/week or more of ethanol in current smokers was estimated at 3.0 (95% CI, 1.8-5.1) compared with nondrinkers among nonsmokers in men. Colorectal cancer attributable to alcohol consumption or smoking was estimated to be 46%. In conclusion, approximately half of the colorectal cancer cases may be preventable by tobacco and alcohol controls in middle-aged and elderly Japanese men.  相似文献   
27.
We examined the placentas of 12 patients in whom congenital cytomegalovirus CMV infection was suspected from serological and or pathological evaluation. Seven patients died including four intrauterine deaths and five survived. On histological examination, the characteristic inclusion bodies were detected in only three placentas, and villitis with plasma cell infiltration was seen in eight placentas. Immunohistochemistry using a specific antibody against CMV improved the sensitivity of CMV detection 10 cases were positive . With the polymerase chain reaction PCR following the extraction of DNA from formaldehyde-fixed placenta samples, CMV DNA was detected in seven cases. All 12 subjects were diagnosed with CMV infection by additional Southern blot analysis after the PCR. CMV DNA was also detected by an in situ hybridization method in all cases. With current molecular biological techniques the placenta can be reliably used for the diagnosis of congenital CMV infection.  相似文献   
28.
PURPOSE: We investigated on a problem of long-term follow up in patients with renal cell carcinoma. PATIENTS AND METHODS: A total of 287 patients with renal cell carcinoma treated in Nara Medical University and affiliated facilities from January 1980 to December 1990 were examined. And we investigated the trend of explanation to patients including 287 patients from 1991 to 1995. RESULTS: Up to December 1995, there are 76 patients (26.5%) unable to be followed and 211 patients able to be followed. The former group patients were less declared cancer rather than the latter group patients. Of 76, 22 patients (28.9%) might misunderstand completely recovering from the cancer disease. For the recent 5 years, those patients who were declared cancer increased, and those patients who were explained benign disease decreased. CONCLUSION: These results suggested that declaration of cancer is important for patients with renal cell carcinoma to be followed for a long-term.  相似文献   
29.
In our ongoing series of anatomical studies to determine the three‐dimensional architecture of the human velar muscles, we have previously reported on the palatopharyngeus. The present study deals with the musculus uvulae (MU), in which the positional relationships of its origin to the posterior nasal spine and the palatine aponeurosis, as well as the interrelation between its anatomical status and functions, have yet to be clarified. Macroscopic and microscopic examinations were performed on 25 and 2 cadavers, respectively. In the former, bilateral MUs and their adjacent structures were exposed mainly from the nasal aspect. In the latter, the soft palates embedded in paraffin were cut into frontal and sagittal sections and alternately processed with HE and Azan stains. The left and right MUs adjacent to each other were found to run longitudinally along the midline beneath the nasal aspect of velum. It was overlaid by glandular tissue that increased in amount as it coursed distally. After originating from the oral surface of palatine aponeurosis, it ran backward to cross above the sling formed by the levator veli palatini muscles of both sides and reached the tip of uvula with its muscle fibers intermingled with glandular tissue. Past studies have proposed three functions of MU to enhance the efficiency of velopharyngeal closure: space occupier, stiffness modifier, and velar extensor. All of the above‐described anatomical characteristics of MU could be explained as being adapted for these functions. This implies that MU is actively responsible for maintaining the velopharyngeal closure efficiency. Clin. Anat. 27:1009–1015, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
30.
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