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The hypo-osmotic swelling test (HOST or HOS test) usually takes into consideration the total HOS response value with no emphasis either on the value of the response subtypes or the response evaluation time. This study investigated the time course of HOS responses and analysed their physiological relevance. Raw semen spermatozoa and Percoll washed spermatozoa were used in the experiment. The morphological changes in the sperm tail were monitored by incubating the spermatozoa in the hypo- osmotic solution for 16 different time periods. The HOS reactive spermatozoa and the type of HOS reaction (swelling subtypes) of the samples subjected to different duration of treatment were identified under a phase contrast microscope. Also the fate of individual spermatozoa in a hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed to a hypo-osmotic solution, the motility lasted usually less than 2 min and motility characteristics were uniquely different from that of the spermatozoa under iso-osmotic conditions. The HOS response development was permanent but the motility loss due to hypo-osmotic shock was reversible up to 1 min of incubation. There was an indication of ordered transition among the HOS swelling subtypes apparently initiating with subtype b destined to c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and increase, respectively, while subtype b showed abrupt initial increase and then gradual decrease. Transition from b to g could be direct or via one or more than one subtypes. Ultrastructure based analysis indicated that HOS response subtypes are the apparent reflection of the differences in the cytoskeletal assembly of the sperm tail and thus may be identifying different physiological variants in the sperm population. These results indicate that shorter incubation is essential to document the kinetics of various HOS responses but the conventional HOS test misses these important HOS features because of lengthy incubation. Since the time course of ordered transition of HOS responses will vary more than the total HOS response in semen of different aetiologies, the importance of HOS response subtypes and response evaluation time should be taken into consideration when applying HOS test.   相似文献   
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PURPOSE: To evaluate the effect of aspirin treatment upon fetal loss in mice with experimental antiphospholipid syndrome (APLS). MATERIALS AND METHODS: Experimental APLS was induced in pregnant mice by passive transfer of mouse monoclonal anticardiolipin antibody. The mice were treated with high (100μg/d) or low (10μg/d) does of aspirin, using vitaminC(100μg/d or 10μg/d)as a control. The mice were assessed for the presence of lupus anticoagulants (prolonged aPTT), thrombocytopenia, degree of fetal resorption rate and mean embryo and placental weights. RESULTS: The mice with APLS had a higher fetal resorption rate(45.7± 12.2% vs 2.5 ± 0.4%, P<0.001), reduced placenta mean weight(104 ± 8 mgvs 169 ±7mg, P<0.001), prolonged aPTT (94± 14sec vs 39±4sec, P<0.001), and reduced mean platelet count(597± 186 ± 103/mm3vs 847±51 ± 103/mm3,P<0.001). The groupof mice with APLS, who were treated with low-dose aspirin, had a lower resorption rate (11.1 ±9.3% vs 45.7±12.2%, P<0.001), a higher placenta mean weight (178 ± 8 mg vs 104 ± 8 mg, P<0.001), a higher mean embryo weight (1042 ± 134 mg vs 721±91 mg, P<0.001), and a lower aPTT (58±15 sec vs 94±14 sec, P, <0.001). Micewho were treated with high-dose aspirin also had a lower resorption rate, although not as much as in the low-dose aspirin group (34.2 ± 12.7% vs 45.7 ± 12.2%, P<0.001). CONCLUSION: Aspirin, especially in low dose, has a protective effect against obstetrical complications associated with experimental APLS.  相似文献   
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目的:肺癌分期与肿瘤直径的关系已被证实是一个预后指标,因此被纳入1986年肺癌分类的国际系统。近年来由于CT飞速发展,人们可以诊断出更小的肺癌,于是有人提倡对肺癌Ⅰ期进一步分期,即根据肿瘤直径小于还是大于30mm,将无确切远处淋巴结转移的病例(Ⅰ期病例)细分为Ⅰa和Ⅰb期。在诊断无症状(即潜伏)的肺癌时,CT普查的开展使人们考虑肿瘤大小的预后价值。在此我们对CT普查诊断的无症状潜伏型肺癌作了分期与大小关系的报道。  相似文献   
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The clinicopathological associations of 33 singleton infants who died with intraventricular haemorrhage (IVH) without hyaline membrane disease (HMD) ('IVH only') were compared with those of 39 infants who died with IVH+HMD over the same gestation range in order to determine what factors other than those related to HMD may contribute to the pathogenesis of IVH. The incidence of 'IVH only' was inversely related to gestational age in the Hammersmith birth population, whereas the incidence of IVH+HMD rose to a peak at 28-29 weeks' gestation. Infants with 'IVH only' lived longer on average than those with IVH+HMD despite a lower birthweight and shorter gestation. Infants who died in the first 12 hours from 'IVH only' had suffered severe birth asphyxia but in those who died later the main symptom was recurrent apnoea. Fewer infants with asphyxia but in those who died later the main symptom was.recurrent apnoea. Fewer infants with 'IVH only' were given alkali therapy or were connected to the ventilator as compared to those with IVH+HMD, but there were no differences in alkali therapy in those who lived for 12 hours or more. In the 'IVH only' group there was a high incidence of haemorrhage from other sites and of bacterial infections. It is suggested that, in the absence of HMD, extreme immaturity is the main factor determining the occurrence of IVH. Birth asphyxia, apnoeic attacks, haemorrhage, and infections may play subsidiary roles, possibly through development of metabolic acidosis.  相似文献   
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Almost all primary retroperitoneal liposarcomas can be classified as well-/dedifferentiated liposarcoma. Rarely, however, primary retroperitoneal liposarcoma is classified as myxoid/round cell liposarcoma, based on the presence of myxoid areas and vascular crow's feet pattern, which has resulted in a debate on the classification of liposarcoma in the retroperitoneum. Genetically, myxoid/round cell liposarcoma and well-/dedifferentiated liposarcoma are different diseases. Myxoid/round cell liposarcoma is characterized by a translocation causing FUS-CHOP or EWSR1-CHOP fusion, whereas well-/dedifferentiated liposarcoma is characterized by an amplification of the 12q13-15 region, including MDM2 and CDK4 genes. As myxoid/round cell liposarcoma is highly radio- and chemosensitive, differentiation between subtypes is important to optimize treatment. We studied whether primary retroperitoneal liposarcomas diagnosed as myxoid/round cell liposarcoma represent molecularly true myxoid/round cell liposarcoma or are histopathological mimics and represent well-/dedifferentiated liposarcoma. Primary retroperitoneal myxoid/round cell liposarcoma (n=16) were compared to primary extremity myxoid/round cell liposarcoma (n=20). Histopathological and immunohistochemical features were studied. Amplification status of the 12q13-15 region was studied using a multiplex ligation-dependent probe amplification analysis, and FUS-CHOP or EWS-CHOP translocations were studied using RT-PCR. In primary retroperitoneal myxoid/round cell liposarcoma, MDM2 and CDK4 staining was both positive in 12 of 15 cases. In primary extremity myxoid/round cell liposarcoma, MDM2 was negative in 18/20 and CDK4 was negative in all cases. Multiplex ligation-dependent probe amplification showed the amplification of 12q13-15 region in 16/16 primary retroperitoneal myxoid/round cell liposarcomas and in 1/20 primary extremity myxoid/round cell liposarcomas. Translocation was present in all (18/18) primary extremity myxoid/round cell liposarcomas, but absent in all primary retroperitoneal myxoid/round cell liposarcomas. On the basis of immunohistochemical and molecular characteristics, apparent primary retroperitoneal myxoid/round cell liposarcoma can be recognized as well-/dedifferentiated liposarcoma with morphological features mimicking myxoid/round cell liposarcoma. In these cases, treatment should probably be specifically designed as for well-/dedifferentiated liposarcoma. Moreover, finding of myxoid/round cell liposarcoma translocations in a retroperitoneal localization is highly suggestive of metastasis and should prompt search for a primary localization outside the retroperitoneum.  相似文献   
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The desire to place esthetically pleasing, conservative, functionally stable, posterior restorative materials has steadily increased over the past 20 years. The creation of successful dentin bonding adhesives and appropriate resin luting cements has paved the way for the development of a myriad of indirect resin-based restorative materials. These materials have been specifically designed to overcome the negative attributes of their porcelain counterparts, and to simplify fabrication, insertion, and post-delivery adjustments. Possibly like no other product before, these restorative materials have met with instant clinical acceptance by many practitioners, and concern exists that these materials have not been sufficiently studied to warrant such widespread acceptance. This article presents an overview of the history and development of resin-based, esthetic, indirect systems, and offers the clinician a review of the literature supporting their role in posterior restorative dentistry. Additionally, a scientifically based protocol for preparation, impressing, provisionalization, and subsequent cementation and adjustment of indirect laboratory-processed resin inlays and onlays is presented.
CLINICAL SIGNIFICANCE
This article reviews the history of indirect laboratory-processed resin restorations, reviews available literature supporting their use, and presents a scientifically based protocol for their placement and use as a viable alternative for conservative reconstruction of posterior teeth.  相似文献   
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