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51.
BACKGROUND: To determine differences in biological features among different adrenal tumors, we investigated the DNA ploidy, numerical chromosomal aberration and proliferative activity in human adrenal cortical neoplasms. METHODS: Our study included six adrenal cortical adenomas with Cushing syndrome, 12 adenomas with hyperaldosteronism, three non-functioning adenomas and three adrenal cortical carcinomas. Isolated nuclei from frozen samples were used for fluorescence in situ hybridization (FISH) analysis, and formalin-fixed, paraffin-embedded tissues from the same materials were analyzed using flow cytometry (FCM) for DNA ploidy. Sections from paraffin blocks were stained immunohistochemically with antibodies against Ki-67 and p53. For FISH analysis, we used an alpha-centromeric enumeration probe for chromosome 17. RESULTS: The mean Ki-67 labeling index (LI) of adrenal cortical carcinomas was markedly higher than that of adrenal cortical adenomas (209.4 vs 8.7). In functional adrenal cortical adenomas, the LI was significantly lower in adenomas with hyperaldosteronism than in those with Cushing syndrome (P = 0.004), although FCM results indicated that tetraploid patterns were more frequently observed in the former type. Tumor size was significantly smaller in adenomas with hyperaldosteronism than in those with Cushing syndrome (P = 0.004). Chromosome 17 showed disomy in all adrenal cortical adenomas, whereas chromosome 17 abnormalities were found in two of three adrenal cortical carcinomas. Only the latter two cases strongly expressed p53 protein. CONCLUSIONS: Our study characterized various biological features of benign and malignant adrenal cortical tumors. The use of a combination of markers might provide additional information to assist our understanding of the clinical behavior of an individual adrenal cortical tumor.  相似文献   
52.
A 35-year-old man was diagnosed as having lung cancer and diedsix years later. In spite of an initial histological diagnosisof squamous cell carcinoma from the biopsy material, the correctdiagnosis of atypical carcinoid was made by sputum cytology.The carcinoid cells had exfoliated into the sputum collectedimmediately after bronchofiberscopic examination although thebronchial tissues obtained at this time did not reveal any histologicalfindings suggestive of neo-plasia. The distinctive cytologicalfeatures in sputum of atypical carcinoid that differentiateit from small cell carcinoma are considered to be the relativelyabundant vesicular cytoplasm and the finely reticular or granularchromatin pattern observed in well-preserved tumor cells. Thepresent case also suggests that clinical data may be indispensableto the differential cytological diagnosis of such tumors.  相似文献   
53.
In order to elucidate the relationship between plasma dehydroepiandrosterone (DHA) and sulpiride-induced hyperprolactinemia (of 60 day duration) in normal men, five normal men (aged 27-46) were administered daily 300 mg of sulpiride orally for 60 days to induce hyperprolactinemia. Plasma levels of prolactin, DHA and cortisol were measured by radioimmunoassay before sulpiride treatment, at day 14 and day 60 after initiation of the treatment. Plasma levels of prolactin after the administration rose significantly (P less than 0.001) to 71.6-95.3 ng/ml in four out of the five subjects compared with those of the controls. In the same four subjects the mean DHA values in plasma were elevated significantly (P less than 0.05) to 877 +/- 160 ng/dl from the mean baseline values (669 +/- 91 ng/dl). The elevated values remained during sulpiride treatment. Plasma levels of cortisol did not change significantly during sulpiride administration in all subjects. Our results suggest that sulpiride-induced hyperprolactinemia sustained at least 14-60 days in normal men stimulates the adrenal cortex to secrete DHA.  相似文献   
54.
AIM: In the present study, an audio-visual sexual stimulation (AVSS) test was used to evaluate the effectiveness of sildenafil, and the AVSS test was coevaluated with the international index of erectile function (IIEF) questionnaire. METHODS: Forty-two patients with erectile dysfunction (ED) were examined (age range, 28-73 years; mean, 51.9 +/- 11.4 years). Each patient answered the IIEF questionnaire and underwent laboratory tests and the AVSS test before administration of sildenafil. The IIEF questionnaire and AVSS test (1 h after administration of 25 mg or 50 mg sildenafil) were re-evaluated in the outpatient clinic 4 weeks later. Questions 3 and 4 of the IIEF test were used to evaluate the effectiveness of sildenafil. Sildenafil was determined to be effective if each score totalled four or five after administration. RESULTS: The rate of effectiveness of sildenafil was 52.4%, and the mean score of the IIEF 5 improved from 7.2 to 15.4 following treatment with sildenafil. The maximum and mean rigidity of the penile tip improved after the sildenafil treatment (36.1%vs 57.7% and 14.2%vs 35.8%, respectively). The maximum and mean rigidity of the penile base rose (42.4%vs 57.7% and 17.9%vs 36.8, respectively). Similarly, following treatment with sildenafil, the penile tumescence increased from 6.6 cm to 7.6 cm at the penile tip and from 7.5 cm to 8.5 cm at the penile base. CONCLUSIONS: In some ED patients the results of the IIEF questionnaire are not always consistent with those of objective evaluation, including AVSS. In these patients, combined assessment using the IIEF and AVSS might be more useful to evaluate the precise effectiveness of sildenafil, rather than relying on the IIEF results alone.  相似文献   
55.
A giant cystic formation was found behind the prostate of a 69-year-old man who presented with urinary retention. Ultrasonography, computed tomography scans and magnetic resonance imaging revealed a large cystic intrapelvic mass and biopsy of the cyst wall diagnosed papillary cyst adenocarcinoma. Immunohistochemically, the tumor originated from the prostate.  相似文献   
56.
Neonatal erythema infectiosum   总被引:1,自引:0,他引:1  
A report is presented of a patient with neonatal erythema infectiosum who developed petechiae, transient thrombocytopenia and transient cardiac failure due to transplacental transmission of human parvovirus B19 (HPV B19) infection. It is suggested that the thrombocytopenia was caused by platelet-associated IgG produced by the patient, and that the cardiac failure may have been caused by direct entry of HPV B19 into the cardiac tissue.  相似文献   
57.
OBJECTIVE: The reported rate of erectile dysfunction after nerve-sparing prostatectomy varies according to physicians. Because exact preservation of the neurovascular bundle (NVB) solely depends on the judgment of the physician, he or she should try to correctly identify the NVB and also avoid neurophysiologic injury of the NVB during the procedure. The purpose of the present study is to assess the status of the NVB preservation by physician's judgment at the operation, the changes in intracavernous pressure related to intraoperative electrical stimulation and postoperative histopathological examination. PATIENTS AND METHODS: Thirty-eight patients who underwent nerve-sparing radical prostatectomy judged by intraoperative electrical stimulation of the NVB were included in this study. Bilateral, unilateral and non-nerve-sparing procedures were performed in 18, 17, and 3 cases, respectively. The NVB preservation evaluated by intraoperative physician's judgment was compared to that evaluated by postoperative histopathological examination. Furthermore, the NVB preservation evaluated by intraoperative electrical stimulation was compared to that by physician's judgment and postoperative histopathological examination. RESULTS: For 68 of 76 NVB (89.5%), intraoperative subjective judgment and histopathological assessment were identical. For 66 of 76 NVB (86.8%), electrical stimulation findings and the physician's judgments were identical, and for 70 of 76 NVB (92.1%), electrical stimulation findings and histopathological findings were identical. CONCLUSION: Even if physicians are convinced of a successful nerve-sparing procedure, there are some cases in which the NVB is not preserved accurately or neurophysiological damage is suffered. Therefore, intraoperative electrical stimulation of the NVB as well as the cavernosal nerve is very useful in evaluation of NVB preservation.  相似文献   
58.
AIM: Bisphosphonates are well established for the management of cancer-induced skeletal complications. Recent studies suggest that bisphosphonates promote apoptosis of cancer cells as well as osteoclasts in bone metastatic sites. To determine the direct effects of bisphosphonate on prostate cancer, we examined the effects of minodronate on prostatic cancer cell growth and the expression of apoptosis-related proteins and osteoclastogenic factors. METHODS: PC-3, DU145 and LNCaP cells were treated with amino-bisphosphonate minodronate. Then proliferation, apoptosis and expression of bcl-2, bax, poly (ADP)-ribose polymerase (PARP), caspase-3, receptor activator of nuclear factor-kappaB ligand (RANKL), osteoprotegerin (OPG), matrix metalloproteinases-2 (MMP-2), and parathyroid hormone related protein (PTHrP) were assessed. RESULTS: The proliferation of prostatic cancer cells was inhibited by minodronate. DNA fragmentation and TUNEL-positive nuclei were observed in minodronate-treated PC-3 cells. Minodronate decreased bcl-2 expression and induced bax expression, caspase-3 activity and degradation of PARP in DU145 and PC-3 cells. Minodronate decreased expression of RANKL, PTHrP and MMP-2 in PC-3 cells. CONCLUSIONS: Our results suggest that bisphosphonate not only promotes apoptosis directly but also decreases pro-osteoclastic gene expression in prostate cancer cells.  相似文献   
59.
60.
E1AF is associated with malignant aggressiveness via regulation of matrix metalloproteinases (MMPs), which play pivotal roles in invasion through the degradation of extracellular matrix of tissues surrounding tumors. However, the clinical significance of E1AF and MMPs in patients with prostate cancer is not fully understood. We reviewed 50 tissue samples from patients with T2‐3N0M0 prostate cancer who had undergone radical operation. Expression levels of E1AF, MMP‐1, ‐3, ‐7, ‐9 and ‐14 were determined semiquantitatively by immunohistochemistry. The mean ± SD percentage of E1AF‐stained cancer cells was 8.56 ± 5.22, and it was significantly higher (p < 0.001) than the E1AF‐immunostaining index of normal cells (1.17 ± 0.61). E1AF immunostaining index in pT3 (12.74 ± 4.80) was significantly higher (p < 0.001) than that in pT2 (5.78 ± 3.31). Although E1AF expression correlated with that of MMP‐7 and MMP‐9 (r = 0.47, p < 0.001 and r = 0.41, p = 0.004, respectively), multivariate analysis showed that E1AF correlated with only MMP‐7 expression (OR = 5.81, 95% CI = 1.27–26.59, p = 0.023). Our results demonstrated that increased expression of E1AF is involved in tumor aggression of prostate cancer. This finding may be influenced by regulation of MMP‐7. We speculate that E1AF is a possible target in treatment and prevention of tumor growth in prostate cancer.  相似文献   
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