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11.
本文对100例慢性粒细胞白血病(CML)患者进行组织病理学研究,应用Hannover国际分类法进行分类,观察到骨髓组织病理学中巨核细胞增多者临床症状较重,中位生存时间较短,认为该分类法对临床及预后判断有指导意义,比既往应用的Bartl及Frisch分类法优越。  相似文献   
12.
This study evaluated the effects of [D-Leu1]Microcystin-LR variants, by the exposure of Hypophthalmichthys molitrix to Microcystis aeruginosa NPLJ4. Fish was placed in aquariums and exposed to 105 cells mL−1. For 15 days, 05 individuals were removed every 05 days, and tissue samples of liver, skeletal muscle and intestinal tract were collected for histopathologic analyses. Following exposure, those surviving were placed in clean water for 15 days to evaluate their recovery. A control without toxins was maintained in the same conditions and exhibited normal histology and no tissue damage. In exposed fish, samples were characterized by serious damages that similarly affected the different organs, such as dissociation of cells, necrosis and haemorrhage. Samples showed signs of recovery but severe damages were still observed. The results should be valuable to analyze the potency of microcystin toxicity and to help in the diagnosis of fish deaths.  相似文献   
13.
我院应用He-Ne激光治疗551例声带小结,取得较好疗效。为研究作用机理,我们进行了免疫功能测定、测温试验、He-Ne激光照射前后的间接喉镜检查、显微结构研究、抑菌试验和过氧化脂质测定。结果提示He-Ne激光照射治疗声带小结的机理为照射后喉部温度升高、血管扩张、血循环加快,从而增强局部营养,促进喉部粘膜生长、消除组织水肿,加速炎性渗出物和毒素的排泄。而He-Ne激光本身没有杀菌和抑菌作用。  相似文献   
14.
Summary The laminar distributions of senile plaques and amyloid -protein (AP) within the striate cortex of patients with Alzheimer's disease (AD) were studied with enhanced Bielschowsky (roughly equivalent to the Campbell technique) and immunohistochemical methods. The laminar distribution of acetylcholinesterase (AChE) fibres within the striate cortex of both AD patients and control patients was studied with an enzyme histochemical method. Quantification of Bielschowsky-stained plaque numbers along intersect lines drawn parallel to laminar boundaries revealed a significant aggregation of plaques at the interface of layers IVc and V. Lines drawn through layer VI intersected significantly fewer plaques than lines through other laminae. Immunoperoxidase staining for AP revealed a similar distribution fo senile plaques, and additional, prominent, diffuse deposits of AP within layers I and IVc. AChE fibres were markedly depleted in the striate cortex of AD cases. In control cases, AChE fibres were, like AP immunoreactivity, concentrated within layers I and IVc. The results indicate that enhanced silver methods may not reveal the complete distribution of AP. The codistribution of AP-immunoreactive diffuse amyloid deposits and AChE fibres to the same cortical laminae is consistent with the possibility that these deposits may be formed from degenerating cholinergic elements. The formation of a line of senile plaques at the interface of two cortical laminae within the striate cortex, in an anatomically analogous situation to a similar line of plaques within the dentate gyrus, suggests that formation of well-defined plaques may be accelerated by the interaction of specific neuronal systems.Supported by a Fellowship from the British Columbia Health Care Research Foundation to TGB. This work is part of the PhD. dissertation of Dr. Beach (University of British Columbia, 1991)  相似文献   
15.
Critical shortages of trained histopathologists limit the capacity of cancer and other clinical services. A survey of histopathology training in 18 European countries conducted by the European Union of Medical Specialists Section of Pathology/European Board of Pathology revealed a considerable shortage of both trained and trainee histopathologists in several of the responding countries. Demographic data indicate a high preponderance of trained histopathologists over 55 years of age and a notable proportion of part-time personnel. Although the training capacity in some countries has been increased, the immediate future of histopathology and the clinical services dependent on the specialty is worrisome. The histopathology workload is growing, and, in some countries, recruitment of trainees is insufficient for future needs. To avert the serious consequences for dependent clinical specialties and their patients, there should be a concerted European action to promote and expand histopathology training.  相似文献   
16.
The inflammatory reactions following subcutaneous application of adjuvants revealed characteristic pathological patterns. The injection of complete Freund's adjuvant (CFA) resulted in the formation of large lipid deposits encircled by an inflammatory reaction and concentrically arranged collagen bundles. Bacterial lipopolysaccharide (LPS) caused granulomatous aggregations of mononuclear cells with thrombotic vessel occlusions. Inoculation of the lipopeptide adjuvants induced accumulation of mononuclear cells with only minimal fibrotic changes which were resolved after day 28. Lipopeptide conjugates based on the head group tripalmitoyl-S-glyceryl-cysteinyl-serin (P3CS) can thus be used as effective immunogens and adjuvants without long-term tissue damage.  相似文献   
17.
Summary This study characterized acute peritonitis and chronic abscess formation resulting from experimental mixed anaerobic infection withBacteroides melaninogenicus andFusobacterium necrophorum. At intervals after infection liver and spleen samples were obtained, fixed, and processed for histological examination. An acute to chronic infection progressed in mice infected with this mixture of anaerobic bacteria, whereas, no infection resulted when either organism was injected alone. Acute inflammatory cell infiltrates were noted in tissue samples at 12 h postinfection. Small, discrete areas of liver cell necrosis with neutrophilic infiltrates were observed as early as 24 h. By 48 h after infection the liver parenchyma was infiltrated with both acute and chronic inflammatory cells, with moderate to severe hepatocyte degeneration recognized at 72 h. Large intrahepatic abscesses were present in the subphrenic (upper lobe) area 2 to 6 weeks after experimental infection.  相似文献   
18.
The mode of occurrence of the D variant of encephalomyocarditis (EMC-D) virus-induced acute sialodacryoadenitis was investigated using three strains of mice differing in their sensitivity to EMC-D virus-induced diabetes (C57BL/6: resistant; BALB/c: moderately sensitive; DBA/2: highly sensitive). Mice were intranasally inoculated with high (10(5) PFU/mouse) or low dose (10(2) PFU/mouse) of EMC-D virus. Although there were individual differences, the blood virus titer generally reached the peak earlier in the high-dose group than in the low-dose group. Signals of viral RNA and histopathological changes were seen in parotid glands and intraorbital and extraorbital lachrymal glands. In these glands, signals of viral RNA and histopathological changes were detected only in acinar cells and initial lesions were characterized by pyknosis of acinar cells. Coagulative necrosis with interstitial inflammatory cell infiltration developed later in parotid glands of BALB/c mice of the high-dose group and in intraorbital and extraorbital lachrymal glands of all groups except for C57BL/6 mice of the low-dose group. Such changes were not observed in epithelial cells of the ductal system. The present results indicate that EMC-D virus shows clear tissue and cell tropism within the salivary and lachrymal glands, probably due to the distribution of receptors for EMC virus.  相似文献   
19.
Lipoblastoma is a relatively rare tumor that occurs in infancy and early childhood and arises from embryonic white fat. Although a benign tumor, lipoblastomas tend to recur and may resemble myxoid liposarcoma. The authors report 26 cases over a 15-year period at Texas Children's Hospital. There was a slight female predilection (14F:12M). The most common symptom was a painless mass with or without increasing size. The trunk, extremities, head and neck, retroperitoneum, inguinal canal, peritoneal cavity, and lung were the tumor sites. Most tumors were circumscribed lipoblastomas and the minority were diffuse infiltrative lipoblastomatosis. Reexcision for residual or recurrent tumor was necessary more frequently in patients with lipoblastomatosis. Histopathologic examination and ultrastructural examination revealed cellular neoplasms composed of immature adipocytes with relatively well-defined septa, frequent lipoblasts, a fine vascular network, and often a myxoid appearance resembling myxoid liposarcoma. Cytogenetics was performed in 4 cases with chromosome 8q abnormality being most common. The major concern with lipoblastoma in children is to completely excise the tumor to avoid leaving residual tumor and to prevent recurrences. Confusion with myxoid liposarcoma, well-differentiated liposarcoma, and typical lipomas may occur. Although asymptomatic, lipoblastomas may cause dysfunction of other organ systems due to mass effect. Complete surgical excision with at least 2 years of follow-up is the preferred therapy.  相似文献   
20.
Reproductive tract abnormalities especially in the uterus and ovaries of cows often results in infertility. The object of this study was to determine the relationship between the cytology of uterine and cervical mucosa and endometrial histopathology in normal and endometritic cows. In this study, the genital tracts of 131 slaughtered cows were collected. According to macroscopic appearances and histopathological evaluation, reproductive tracts were divided into normal and abnormal. Cytological samples were obtained from the discharges of cervical mucosa and uterine fluid that were collected by wet cotton swab and gentle aspiration. Differential cellular counts were carried on Giemsa stained smears of the mucosa. Comparison of cell densities of normal cows with endometritic cows showed significant differences (P<0.05) in the macrophage presence both by swab (0.00±0.00) and aspiration (0.16±0.55) methods. Comparison of cell densities in different grades of endometritis showed a significant difference (P<0.05) in the neutrophil percentage in cervical mucosa between the swabbing and aspiration methods. In this study, there were no significant differences in cell densities between the two collection methods in cows affected with either acute or chronic endometritis. However, there was significant difference in the neutrophil density in aspirated cervical mucosa compared to the swab collection in cows affected with subacute endometritis. Cytological methods can be useful for the diagnosis of clinical and subclinical endometritis of cows.  相似文献   
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