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101.
PURPOSE: We re-evaluated histopathological specimens of head and neck early-stage extranodal non-Hodgkin's lymphoma (NHL) using the revised European and American lymphoma (REAL) classification, and also investigated the relationship between the clinical characteristics and histopathological classification in an attempt to evaluate the usefulness of this new classification system in selecting treatment modalities. MATERIALS AND METHODS: Between 1979 and 1995, 117 patients with histologically confirmed stages I and II NHL of head-and-neck extranodal regions were treated. Of these patients, 110 specimens were available for re-evaluation. Sixty-four patients had Stage I, and 46 had Stage II diseases. All but 3 had received radiation therapy, and 59 patients were also treated with intensive combination chemotherapy. RESULTS: There were 32 extranodal marginal-zone B-cell lymphomas, 57 diffuse large B-cell lymphomas, 11 peripheral T/NK-cell lymphomas, and 10 others. The 5- and 10-year cause-specific survival rates for all patients were 72% and 62%, respectively. Patients with extranodal marginal-zone B-cell lymphoma or other low-grade B-cell lymphomas demonstrated higher survival rates than patients with other lymphomas. Patients with peripheral T/NK lymphomas showed the lowest survival rate. CONCLUSION: The REAL classification accurately indicated the prognosis of patients with NHL. These results suggest that appropriate treatment modalities can be selected using this classification.  相似文献   
102.
103.
Nitrobenezene (NB) produces germ cell degeneration, especially of spermatocytes in rats. To examine the possible involvement of apoptosis in this process, the extent and nature of nuclear DNA fragmentation after NB dosing were assessed using both terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) and DNA gel electrophoresis, in addition to conventional histological and electron microscopic procedures. Adult Sprague Dawley rats were treated with a single oral dose of NB (250 mg/kg) and euthanized subsequently at 6, 12, and 24 h and 2, 3, 5, and 7 days. The earliest morphological signs of germ cell degeneration in testes were found in pachytene spermatocytes 24 h after dosing. Electron micrographs of degenerating spermatocytes showed marked nuclear chromatin condensation at the nuclear periphery and crowding of cytoplasmic constituents, which are characteristic of apoptosis. Coincident with the appearance of such morphological changes, degenerating spermatocytes contained fragmented DNA as revealed by TUNEL. The presence of DNA laddering, a hallmark of apoptosis on gel electrophoresis, was first apparent and most prominent at 24 h, gradually becoming less detectable. No such changes were observed up to 12 h after dosing or in control animals. These results demonstrated unequivocal involvement of apoptosis in the induction of germ cell degeneration caused by NB. Received: 29 September 1997 / Accepted: 6 January 1998  相似文献   
104.
105.
Summary High single-dose alternate-day prednisolone therapy (ADT) was compared with daily-dose prednisolone therapy (DDT) for treatment of polymyositis. Thirty patients with polymositis were treated with ADT for an average of 33.9 months. The combined number of improvements was 21 out of 30, a response rate of 70%. Side-effects were very rare and mild. On the other hand, 9 of 17 patients treated with DDT for an average 18.5 months improved, a response rate of 53%. The incidence of side-effects was strikingly higher than with ADT. ADT is therefore strongly advocated for treatment of polymyositis to avoid infectious complications and lessen cushingoid side-effects.  相似文献   
106.
Adult T cell leukemia was classified into two distinct types, monomorphic and pleomorphic, according to their histological and cytological features. The former type is composed of uniform neoplastic cells with round or slightly indented nuclei without any marked deformation. The latter type, on the other hand, occupies a unique position in lymphocytic leukemias with the following characteristics: a) onset in adulthood, b) an acute and subacute course, c) well-differentiated T cell origin of the neoplastic cells, d) pleomor-phism of the neoplstic cells with markedly deformed nuclei, e) difkuse proliferation of the neoplastic cells without nodular pattern, f) histologically heterogeneous features of lymph nodes frequently admixing a cluster of normal lymphocytes, proliferation of macrophages and dendritic cells, and well-developed high endothelium venules, g) high incidence of skin lesions due to the infiltration of neoplastic cells, and h) exclusively limited localization of patients' birth places.  相似文献   
107.
Recent studies have examined cellular kinetics and genetic abnormalities in colorectal polyps with epithelial serrated proliferation (CP-ESP), including hyperplastic polyps, serrated adenomas, and tubulovillous adenomas. However, difficulty in histologically classifying these lesions and the lack of clear-cut diagnostic criteria have led to inconsistent findings. Some 60 cases of CP-ESP and 6 cases of CP-ESP with malignant transformation were studied. When nuclear size progressively decreased from the bottom and middle layers to the surface layer of the crypts, maturation gradient was considered positive. CP-ESP and CP-ESP adjacent to carcinoma were morphologically classified as being positive or negative for maturation gradient and inferior and lateral glandular branching. Cellular kinetics were evaluated using Ki-67 immunostaining, and polymerase chain reaction (PCR)-dependent preferential homoduplex formation assay was performed to detect the presence or absence of K-ras codon 12-point mutations. CP-ESPs were morphologically classified into five types. In CP-ESP of types 1 to 4, the proliferation zone was confined to the bottom layer of the crypts or extended from the bottom to middle layers. In contrast, the proliferation zone extended throughout the crypts in most type 5 lesions. K-ras codon 12 mutations were detected in only types 3 and 5 CP-ESP. The five histomorphologic types of CP-ESP have distinct patterns of cellular kinetics. Histomorphologically, type 3 CP-ESP is considered an atypical hyperplastic polyp, occasionally associated with an elongated proliferation zone or K-ras mutations. Preliminary evidence indicates some relation between K-ras mutations and structural atypia associated with lateral branching of the crypts.  相似文献   
108.
Donor dendritic cells (DC) migrate into the recipient spleen after hepatic transplantation. Immunological unresponsiveness to rat hepatic allografts can be induced by prior donor-specific blood transfusion (DST). We investigated homing receptor phenotype and splenic distribution of donor DC after allografting and DST. Immunostaining revealed OX62+ cells in the splenic red pulp of animals receiving pre-transplant DST but only in the white pulp of untreated animals. Most OX62 cells were positive for OX76. There were two subsets of DC in the spleen, CD45RChighOX62+ and CD45RClowOX62+ cells. RT-PCR revealed that CD45RClowOX62+ cells expressed interleukin (IL)-10, while CD45RChighOX62+ cells expressed IL-2 and low levels of IL-10 mRNA. CD45RChighOX62+ cells strongly expressed CCR5 and CCR7, compared with weak expression in CD45RClowOX62+ cells. The Epstein-Barr virus-induced molecule 1 (EBI-1) ligand chemokine (ELC/MIP3beta) was expressed mainly within the splenic white pulp. Mucosal vascular addressin-cell adhesion molecule-1 (MAdCAM-1) was expressed in the marginal zone and white pulp, but expression of splenic MAdCAM-1 was down-regulated in DST-treated animals. L-selectin (CD62L), the ligand for MAdCAM-1, was strongly expressed on CD45RChighOX62+ cells but not on CD45RClowOX62+ cells. In conclusion, differential splenic migration of CCR5lowCCR7lowCD62Llow CD45RClow DC expressing Th2-type cytokines is associated with immunological unresponsiveness to rat hepatic allografts.  相似文献   
109.
The attainment of maximal peak bone mass early on in life is one of the most important strategies for the prevention of osteoporosis in women. The aim of this study was to clarify the correlation between gains in body size in all growth phases in childhood and adult bone mass in women. The subjects were 86 female first-year university students, aged 18–21 years. We measured the subjects bone mineral content (BMC) and bone mineral density (BMD) at the lumbar spine and the left hip, including the femoral neck, with dual energy X-ray absorptiometry. Each subject was measured for current height and weight. Height and weight at birth, and at 1.5, and 3 years were obtained from each maternity record book, and those between 6 and 18 years were obtained from their school health records. Other information, including physical activity and calcium intake, was obtained through an interview. Bivariate analysis showed that weight gains during the periods from birth to 1.5 years and from 9 to 12 years significantly correlated with both BMC and BMD values at any site. The stepwise method of multiple regression analysis showed that a weight gain during the period from birth to 1.5 years was significantly associated with BMC at the lumbar spine (P = 0.0001) and at the femoral neck (P = 0.0290) and with BMD at the lumbar spine (P = 0.0387). Birth weight was significantly associated with BMC at the lumbar spine (P = 0.0474) and the total hip (P = 0.0352), and weight gain during the period from 9 to 12 years was significantly associated with BMC at the femoral neck (P = 0.0376). In conclusion, birth weight and weight gain in infancy are important determinants of bone mass in young women. Additionally, a girls prepubertal growth spurt is likely to be a key phase for the acquisition of bone mass in relation to body weight. Our findings suggest that osteoporosis prevention programs may need to start very early in the life cycle.  相似文献   
110.
Objective To assess whetherLegionella pneumophila serogroup 1 and serogroup 6,Escherichia coli, andStaphylococcus aureus can survive in Japan Sea Proper Water (JSPW). Methods The inhibitory effects of JSPW, surface seawater (SSW), phosphate buffer solution with 3.5% NaCl of pH 7.0 (3.5% NaCIPBS), and the 102- and 104-fold dilute solutions with purified water or phosphate buffer solution of pH 7.0, and purified water were investigated. Survival cells were counted immediately after the water and the bacteria were mixed, and at 1,3,5, and 7 days after incubation at 37°C. If the number of surviving cells was decreased more than 2 log units compared with the starting value, we judged the medium to have had an inhibitory effect on the growth of the bacteria. Results The survival cells of the bacteria in JSPW had decreased more than 2 log units compared with the starting value at 1 day after incubation. After 1 day of incubation, the cells ofLegionella pneumophila serogroup 6 andStaphylococcus aureus were found to have decreased more than 2 log units in purified water (PW) used as a control. Furthermore,Legionella pneumophila serogroup 1 in the 102-fold dilute solution of JSPW was only 1.04 log units lower than the starting value at 7 days after incubation. In the 102- and 104-fold dilute solutions of JSPW,Escherichia coli survived for 7 days after incubation. These results were almost similar to the results in SSW and 3.5% NaCIPBS. Conclusions The present findings demonstrate thatLegionella pneumophila serogroup 1 andEscherichia coli cannot survive in undiluted JSPW for over a day at 37°C, suggesting the inhibitory effects may be due to the sodium chloride contained in JSPW.  相似文献   
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