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Elderly onset rheumatoid arthritis (RA) is difficult to diagnose definitively when the patients note their first symptoms of arthritis above the age of 75 years old. In this report, we reviewed the clinical features of elderly onset RA and its diagnosis. The subjects included 4 females, aged 78, 83, 84 and 93 years, respectively. The onsets were abrupt in 2 cases and more slowly arriving in the other 2. Shoulder joints and wrist joints were involved in all cases. Knee joints, finger joints and foot joints were involved in 3 cases and the elbow was involved in one case. Anti-RA treatment quickly attenuated the acute and severe arthritis and brought down the high CRP level associated with vivid inflammatory activity of RA. The RAPA value was very high in all but one of the cases. Severe destructive findings in radiography was undetectable in the major joints (e.g. shoulder, hip and knee joints). Radiographic findings in wrist and finger joints were also very difficult to differentiate from arthrosis and osteoporosis. On the other hand, RA involvement in the cervical spine was certain in the radiographs; 1 case had anterior atlantoaxial subluxation and 2 cases had subaxial intervertebral erosion. Pathological radiographic findings in the cervical spine are useful for the diagnosis of elderly onset RA.  相似文献   
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The majority of skull base tumors have been considered inoperable not because of the difficulty of surgical removal, but for lack of reliable methods to reconstruct the skull base following extensive removal of those tumors. In this report a trial fo reconstruction using a transplanted omentum is described. A free sheet of vascularized omentum was taken via laparotomy and transplanted into the skull base in four patients who had undergone extensive resection of skull base tumors. The transplanted omentum served satisfactorily as a barrier to prevent CSF leakage and subsequent infection and was considered to be a reliable material to reconstruct large defects in the skull base. The advantage of the omentum is its applicability in covering defects of all sizes and shapes. The omentum also contains various factors to promote tissue adhesion, such as angiogenic factors and fibroblastic growth factors. Furthermore, it can be expected to prevent secondary infections of the transplanted area, and as being a defense organ in the abdominal cavity. Practical methods to harvest and transplant the free vascularized omentum are described, and four cases of patients who have undergone these procedures are reported.  相似文献   
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This study examines the pulmonary hemodynamics during reimplantation and rejection following unilateral lung transplantation in dogs. Nineteen mongrel dogs were divided into three groups according to the method of treatment used: group 1 (n = 6) underwent modified autotransplantation of the left lung; group 2 (n = 6), allotransplantation without immunosuppression; and group 3 (n = 7), allotransplantation with immunosuppression. The pulmonary arterial blood flow and ventilation scores, assessed by chest X-rays, were measured for 2 weeks postoperatively. Pulmonary blood flow to the transplanted lung decreased slightly in group 1, whereas in group 2, it decreased sharply from the 3rd postoperative day (POD) and was almost completely absent by the 14th POD. In group 3, it decreased by 28% on the 1st POD but recovered gradually to 37% by the 14th POD. Ventilation scores were the same among the three groups on the 1st POD but in group 2, they decreased rapidly from the 3rd POD. This change correlated well with that of the pulmonary arterial (PA) flow, although the ventilation score changed after the PA flow did. In conclusion, rejection was reflected earlier and more distinctly by the changes in PA flow than by chest X-rays.  相似文献   
6.
Morphological alterations in the lungs of rats deficient in either or both of vitamin E and essential fatty acids were investigated after exposure to hyperoxia for 48h. In rats deficient in both vitamin E and essential fatty acids, there was damage to type-2 alveolar cells observed as swollen mitochondria and bleb formation in the cytoplasm. None of these changes was found in rats deficient in only one of these substances. Hyperoxia in rats deficient in both substance also caused destruction of the capillary endothelial cells and edema in the interstitium. The lungs of rats deficient in only one of the substances showed some edema in the capillary endothelial cells, but not destruction, and less interstitial edema. These findings suggest that simultaneous deficiency in vitamin E and essential fatty acids facilitates lung damage in rats exposed to hyperoxia.(Murakami R, Obara H, Momota T et al.: The effect of hyperoxia on the lungs of rats deficient in essential fatty acids. J Anesth 3: 149–154, 1989)  相似文献   
7.
In order to detect human papillomavirus (HPV) DNA in invasive cervical cancers, three different polymerase chain reactions to amplify different subgenomic fragments of HPV DNA were carried out on DNA extracted from 93 formalin-fixed and paraffin-embedded tumor tissues. This study detected HPV DNA in 54 cases (58.1%), which broke down to HPV 16 in 39 (41.9%) cases, HPV 18 in six (6.4%), HPV 52 in three, HPV 33 in one and unclassified HPV type in the remainder. Histopathologically, squamous cell carcinomas frequently contained HPV 16, whereas, HPV 18 was present in adenocarcinoma, adenosquamous cell carcinoma and small cell carcinoma of the cervix. Clinicopathological study revealed that HPV 16 and 18 DNA found were more frequently than other HPV subtypes in premenopausal patients. Moreover, HPV 18 DNA-positive cancers had a relatively high recurrence rate. These results indicate that cervical cancers might be clinically influenced by the difference in subtypes of the infecting HPV.  相似文献   
8.
A rare duct-islet cell tumor of the pancreas was studied using immunohistochemical, cytofluorometric and histochemical methods. Histology and immunohistochemistry revealed that the tumor contained two distinct cell types; islet cell-like neuroendocrine cells and exocrine duct cell components, suggesting an endodermal origin for both types. The cells showed marked pleomorphism an vascular and perineural invasion at the tumor periphery. Cytofluorometric study of the tumor cell DNA revealed an increased mean nuclear DNA content, without any aneuploidy. Histochemically, the tumor cells contained an increased number of argyrophilic nucleolar organizer regions (AgNORs) in their nuclei. The malignant potential of this duct-islet cell tumor was suggested.  相似文献   
9.
Although calcitonin is well known to be a potent inhibitor of bone resorption, it remains unknown how it regulates osteoclastic H(+) transport. In this study, we examined the effects of calcitonin on H(+) extrusion in cultured rat resorbing osteoclasts using an intracellular pH (pHi) indicator, BCECF [2'7'-bis-(2-carboxyethyl)- 5-carboxyfluorescein]. Resorbing osteoclasts were identified by their formation of resorbing pits on calcium phosphate-coated quartz coverslips. Both basal pHi and H(+) extrusion activity were significantly higher compared to non-resorbing osteoclasts. Two types of H(+)-extruding systems were identified by pharmacological and immunocytochemical means: a bafilomycin-A(1)-sensitive and an amiloride-sensitive system [H(+) extrusion mediated by a vacuolar type proton pump (V-ATPase) and by a Na(+)/H(+) exchanger (NHE), respectively]. Calcitonin inhibited both H(+) extrusion activities in a dose-dependent manner and this action was mimicked by protein kinase A (PKA) activators, but not by protein kinase C (PKC) activators. Pretreatment with PKA inhibitors completely suppressed calcitonin-induced inhibition, whereas neither PKC inhibitors nor calcium chelators suppressed it. These results indicate that calcitonin inhibits H(+) extrusion generated by V-ATPase and NHE via PKA activation. These inhibitory mechanisms of H(+) transport by calcitonin are important for the regulation of bone resorption.  相似文献   
10.
The conformational energies of poly(α-methylene-γ-butyrolactone) are calculated and compared with those of poly(methyl methacrylate). In spite of the structural resemblance of these two polymers, the patterns of the energy contour maps are clearly distinguishable from each other; the energy barriers between rotational isomeric states are appreciably higher in the former than in the latter polymer. The calculation indicates large non-bonded interactions between the protons in one lactone ring and those in the adjacent lactone rings. The broad NMR spectrum of poly(α-methylene-γ-butyrolactone) apparently reflects its rigid conformational structure. 1H and 13C NMR chemical shifts are calculated by theoretical shielding calculations based on conformational analysis. Much lower magnetic field resonances of the O? CH2 and α-CH2 carbons in poly(α-methylene-γ-butyrolactone) as compared with those of the O? CH3 and α-CH3 carbons in poly(methyl methacrylate) are well reproduced by the calculation. The shift to lower magnetic field is mainly attributed to paramagnetic shielding derived from the interaction between O? CH2 carbon and α-CH2 carbon. Tacticity- and conformation-dependent 1H and 13C NMR chemical shifts of poly(α-methylene-γ-butyrolactone) are well interpreted on the basis of the conformational analysis.  相似文献   
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