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1.
Seventy seven antral biopsies were collected from patients attending endoscopy clinic at King Khalid University Hospital, Riyadh, Saudi Arabia during a period of six months between December 1988 to May 1989. Of these 69 (89.6%) showed chronic gastritis as well as Helicobacter-like organisms (HLOs) in the biopsy specimens while 63 (81.8%) of biopsies grew Helicobacter pylori on culture. These findings indicate a good correlation between the histological diagnosis of chronic gastritis and isolation of H. pylori on culture.  相似文献   
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OBJECTIVE: The aim of the study was to review all the cases of ameloblastoma seen at the Oral and Maxillofacial Surgery Clinic of the Lagos University Teaching Hospital, Nigeria, between 1980 and 2003. METHODS AND MATERIALS: In this retrospective study, case files and biopsy reports of new cases of ameloblastoma covering a 24-year period were retrieved and analyzed for sex, age on presentation, histologic type, and site distribution. RESULTS: A total of 207 cases of ameloblastoma were seen in the given period. One hundred and ninety-eight (95.7%) were benign, and 9 (4.3%) were malignant. A male-to-female ratio of 1.1:1 was found. The average ages on presentation for ameloblastoma and ameloblastic carcinoma were 31.67 and 46.44 years, respectively. The lesion was found to be more common in the premolar-molar region of the mandible. The most common histologic type was follicular ameloblastoma (25.1%). Nine (4.3%) cases of ameloblastic carcinoma were also reported. CONCLUSIONS: Ameloblastoma with a predilection for the posterior mandibular region is relatively common in our environment. Sex and site distributions are similar to previous reports in the literature.  相似文献   
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Folayan  Morenike Oluwatoyin  Ibigbami  Olanrewaju  Brown  Brandon  El Tantawi  Maha  Uzochukwu  Benjamin  Ezechi  Oliver C.  Aly  Nourhan M.  Abeldaño  Giuliana Florencia  Ara  Eshrat  Ayanore  Martin Amogre  Ayoola  Oluwagbemiga O.  Osamika  Bamidele Emmanuel  Ellakany  Passent  Gaffar  Balgis  Idigbe  Ifeoma  Ishabiyi  Anthonia Omotola  Jafer  Mohammed  Khan  Abeedha Tu-Allah  Khalid  Zumama  Lawal  Folake Barakat  Lusher  Joanne  Nzimande  Ntombifuthi P.  Popoola  Bamidele Olubukola  Quadri  Mir Faeq Ali  Rashwan  Maher  Roque  Mark  Shamala  Anas  Al-Tammemi  Ala’a B.  Yousaf  Muhammad Abrar  Abeldaño Zuñiga  Roberto Ariel  Okeibunor  Joseph Chukwudi  Nguyen  Annie Lu 《AIDS and behavior》2022,26(3):739-751
AIDS and Behavior - The aim of the study was to assess if there were significant differences in the adoption of COVID-19 risk preventive behaviors and experience of food insecurity by people living...  相似文献   
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In the present study, expressions of 17B-hydroxysteroid dehydrogenase (17HSD) types 1, 2 and 3, 5α-reductase type 2 and human androgen receptor mRNAs were determined in 12 benign prostatic hyperplasia and 17 prostatic carcinoma specimens. 17HSD type 2 was found to be the principal isoenzyme expressed in the prostate. Significantly higher expressions of 17HSD type 2 and 5α-reductase type 2 were detected in benign prostatic hyperplasia compared with the carcinoma specimens. Expression of the androgen receptor in the 2 groups was not significantly different. 17HSD type 3 mRNA was not detected in any of the specimens investigated. Only low constitutive expression of the 2.3 kb mRNA of 17HSD type I was seen. Immunohistochemical analyses indicated that this did not lead to significant enzyme expression, only faint staining for the enzyme protein being detected, mainly in uroepithelial cells. No significant correlation was found between any of the mRNAs analyzed, but the data on 5α-reductase type 2 mRNA support the presence of an increased proportion of 5α-dihydrotesterone in the hyperplastic prostate. In cultured PC-3 prostatic cancer cells and in transiently transfected human embryonic kidney 293 cells, 17HSD type 2 was found exclusively to convert 5α-dihydrotestosterone and testosterone into the less potent 17-keto compounds 5α-androstanedione and 4-androstenedione, respectively. We suggest that the 17HSD type 2 isoenzyme plays a part in the metabolic pathway, resulting in the inactivation of testosterone and 5α-dihydrotestosterone locally in the prostate. The enzyme expressed in the prostate could, therefore, protect cells from excessive androgen action. © 1996 Wiley-Liss, Inc.  相似文献   
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OBJECTIVE: This study sought to determine the relative frequency of odontogenic tumors in a Nigerian population and to compare these data with previous reports. STUDY DESIGN: Records of patients seen at the Lagos University Teaching Hospital between January 1980 and December 2003, with histologic diagnosis of odontogenic tumors (based on World Health Organisation classification, 1992), were analyzed. RESULTS: Odontogenic tumors constituted 9.6% of all the biopsies of oral and jaw lesions seen within the period under study. Three hundred and eight (96.6%) were intraosseous, and 11 (3.4%) were peripheral (peripheral odontogenic fibroma=7; peripheral myxoma=3; peripheral ameloblastoma=1). The mean age of patients was 29.9+/-15.6 years (range, 4-85 years). Among these cases, 96.6% of the tumors were benign and 3.4% were malignant. Ameloblastoma with predilection for the mandible was the most frequent odontogenic tumor (63%), followed by adenomatoid odontogenic tumor (AOT) (7.5%), myxoma (6.5%), calcifying epithelial odontogenic cyst (5.3%), and odontogenic fibroma (5.3%). More cases of malignant odontogenic tumors were seen than cases of calcifying epithelial odontogenic tumor and odontomas. The mean ages of patients with AOT, ameloblastic fibroma, and odontoma were significantly lower than those with ameloblastoma ( P<.05). No significant difference was found between the mean ages of patients with benign odontogenic tumors and those with malignant odontogenic tumors ( P=.058). CONCLUSIONS: Odontogenic tumors, especially ameloblastoma, are not considered rare among Nigerians, whereas odontoma, regarded as the most frequent odontogenic tumor in North and South America, is rare.  相似文献   
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The objective of this study was to determine the incidence of gastroesophageal reflux (GER) as documented by extended esophageal pH monitoring in symptomatic premature infants and to identify its relationship with chronic lung disease (CLD). This was a retrospective study of 629 infants born < 32 weeks gestational age and admitted to the neonatal intensive care unit during the study period. Univariate analyses were done on the 137 infants undergoing the test for the association of the following risk factors with acid reflux: birth weight, gestational age, race, sex, length of stay, bronchopulmonary dysplasia (BPD; O2 requirement at 28 days), and severe CLD (O2 requirement at 36 weeks postmenstrual age). Eighty-seven of 137 infants were positive for GER. There was no association of GER with the risk factors studied, nor were there correlations with BPD or severe CLD. GER is common (63%) in premature infants < 32 weeks gestational age but clinical symptoms and CLD are poorly correlated with this diagnosis.  相似文献   
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