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61.
SETTING: This report investigates the unusual transmission of Mycobacterium tuberculosis from a 12-week-old infant with nosocomially acquired tuberculosis (TB). Compliance with recommendations on the post-exposure management of young children is described. DESIGN: Contacts of an infant case of TB were identified and recommended to undergo baseline and post-exposure tuberculin skin tests (TST) as per Canadian TB standards. TST conversion was measured at least 8 weeks post exposure. Children aged <6 years were recommended to initiate preventive treatment with isoniazid (INH) until their post-exposure TST. Information on TST results and adherence to therapy were analysed from existing medical records. RESULTS: Overall, 17 TST conversions were documented among 732 contacts: both parents, two health care workers (HCWs) who provided close care, and several patients, visitors and one staff member without obvious close contact. Of 65 eligible children, 46% completed post-exposure therapy as recommended. The most common reasons for treatment failure were concern about side effects, perception of low risk and lack of physician support. CONCLUSION: This investigation suggests that all children, including infants, with cough and numerous bacilli or extensive pulmonary disease should be considered infectious. Health care provider education is necessary to resolve the observed low compliance with current post-exposure management guidelines.  相似文献   
62.
We prepared a novel recombinant tumor necrosis factor-alpha (TNF) mutant (mutant 471), in which 7 N-terminal amino-acids were deleted and Pro8Ser9Asp10 was replaced by ArgLysArg, and compared its biological activity with that of wild-type recombinant TNF. Mutant 471 had a 7-fold higher anti-tumor activity against murine L-M cells in vitro, and a higher binding activity to TNF receptors on L-M cells, than wild-type TNF. Furthermore, mutant 471 showed a higher anti-tumor effect on murine Meth A-HM tumors transplanted into BALB/c mice, with complete regression of the tumors being observed in the animals. The possible cachectin activity of mutant 471 was almost the same as that of wild-type TNF. The acute lethal toxicity of mutant 471 in beta-D-galactosamine-sensitized C3H/HeJ mice was 18 times lower than that of wild-type TNF. These results suggest that mutant 471 might be a more promising anti-cancer agent than wild-type TNF.  相似文献   
63.
OBJECTIVE: To test the following hypotheses in hemifacial microsomia (HFM): (1) the volumes of the masseter, lateral and medial pterygoid, and temporal muscles are reduced on the affected versus unaffected side; (2) significant differences exist between the degrees of right-left disproportion in these four masticatory muscles; (3) circumferential shapes of the masticatory muscles are more irregular on the affected versus unaffected side; and (4) the degree of masticatory muscle right-left disproportion can be judged by the degree of ear, mandibular, or dental anomalies. SUBJECTS AND METHODS: Ten preadolescent patients with HFM were studied using facial photographs, dental casts, cephalometric and panoramic radiographs, and helical computed tomography scanning and three-dimensional reconstruction technique. Volumes of masseter, lateral and medial pterygoid, and temporal muscles on both sides were measured. Muscle volume disproportion was expressed as the affected/unaffected ratio. Muscle circumferential irregularity was expressed as the ratio between the total circumferential length and corresponding cross-sectional area. RESULTS: Masticatory muscle volumes were significantly smaller on the affected versus unaffected side. No significant differences were observed between the degrees of disproportion of the four masticatory muscles examined. Circumferential shapes of masticatory muscles were significantly more irregular on the affected versus unaffected side. There were no significant relationships of the degree of ear, mandibular, or dental anomalies in relation to masticatory muscle disproportion. CONCLUSIONS: In HFM the masseter, lateral and medial pterygoid, and temporal muscles all have a significantly smaller volume on the affected versus unaffected side, and specific muscles were not severely affected in the present subjects. Furthermore, all four muscles showed a significantly more irregular shape on the affected versus unaffected side. Finally, the severity of masticatory muscle disproportion can probably not be judged by the degree of ear, mandibular, and dental anomalies in preadolescent patients with HFM.  相似文献   
64.
OBJECTIVE: In this report, the orthodontic treatment combined with rigid external distraction osteogenesis in a 5.5-year-old girl with midfacial hypoplasia and oligodontia is described. PATIENT: The child presented with a reduced maxilla, protruding lower lip, skeletal Class III jaw relationship with a low mandibular plane angle, a short and flattened nose, anterior crossbite, and aplasia of 16 permanent teeth. The patient was treated with rigid external maxillary distraction osteogenesis, maxillary protraction headgear, and Class III elastics. Following treatment, the maxilla was displaced in a forward direction with new bone formation at the tuberosities and the mandible rotated backward in relation to the anterior cranial base. The anterior crossbite was corrected, and the skeletal jaw relationship changed from a Class III to a Class I skeletal pattern. The soft tissue facial profile showed that the nasal projection had been increased, the nasolabial angle increased, and the lower lip protrusion was reduced. Postoperative treatment results were acceptable. CONCLUSION: This report documents that early maxillary advancement with rigid external osteogenesis offers a promising treatment alternative for a very young patient with maxillary hypoplasia and oligodontia.  相似文献   
65.
Craniofacial morphology in a patient with Simpson-Golabi-Behmel syndrome.   总被引:1,自引:0,他引:1  
OBJECTIVE: We present the case of a 6-year-old boy with a coarse face, cleft palate, and malocclusion with anterior open bite who had been diagnosed with Simpson-Golabi-Behmel syndrome. Morphology of the craniofacial structures was examined on the basis of conventional radiographs, three-dimensional (3D) computed tomography (CT) and magnetic resonance (MR) scanning. PATIENT: This patient had 13 ribs on the right side, slight scoliosis, supernumerary nipples, a coarse face, hypertelorism, a short broad upturned nose, a wide mouth, a straight facial profile with incompetence of the lips, midline groove of tongue, and cleft palate. The patient also had severe anterior open bite, a distal step-type molar relationship, five congenitally missing teeth, and a supernumerary tooth. Lateral cephalometric analysis revealed a large anterior cranial base, a large maxilla and mandible, a large inferior face height, and skeletal Class I jaw relationship with a high mandibular plane angle and large gonial angle. The 3D CT image showed a large cranium, a long face height, and prominent skull sutures. The MR image showed a large tongue, midline groove of the tongue, and a small space between tongue and palate.  相似文献   
66.
We report the clinicopathological findings of astroblastoma found in an 8‐year‐old girl who was subsequently treated for 11 years. The primary superficially circumscribed tumor was located in the frontoparietal lobe, while the recurrent and the second recurrent tumor were restricted to the same region 11 years later. The tumors obtained on these three occasions showed fundamentally the same histological, immunohistochemical and fine structural features. They exhibited astrocytic as well as ependymal tanycytic features with apparent epithelial cell lineage. The tumor cells showed typical features of astroblastoma comprising prominent perivascular pseudorosettes with remarkable vascular sclerosis. The immunohistochemical study revealed intensive positivity of GFAP, vimentin, epithelial membrane antigen (EMA), cytokeratin, connexin 26 and 32, desmocollin 1 and neuronal cadherin. The fine structure revealed divergent types of junctional complexes, some of which were connected with tonofilament bundles. Numerous microvilli protruded and basal lamina abutted on the tumor cell surface. We report these unique histological features, and stress that astroblastoma should be categorized as a specific type of neuroepithelial tumor.  相似文献   
67.
Similarly to the results reported in pregnancy and during oral contraceptive use, estrogen replacement therapy (ERT) had a lowering effect on serum immunoglobulins (IgG, IgA, IgM) of 20 postmenopausal women with a mean age of 52.2 years, in parallel with an increase in the blood values of estradiol (E2). The clinical implications of this phenomenon warrant the study on a bigger series and during a longer period of time. It is recommended to use with precaution the ERT in women with known defects in the immunologic system. A study on the effect of the new transdermal therapeutic system (Estraderm, TTS, Ciba) on the immunoglobulins is in course.  相似文献   
68.
A phyllodes tumor of the breast can grow into an extremely large oncoides occasionally and be a cause of poor prognosis without adequate treatment in some cases. A case of giant phyllodes tumor which is thought to be one of the largest and heaviest among reported cases in Japan was treated in our clinic. The process of enlargement of the tumor and the treatment of this patient are reported.  相似文献   
69.
Aim: We aimed to identify the candidates for antiviral therapy, among patients who are hepatitis C virus (HCV) carriers with normal serum aminotransferase (ALT), focused on the inhibition of hepatocellular carcinoma (HCC). Methods: Four hundred and sixty-four HCV carriers with normal serum ALT and 129 HCV carriers with persistently normal ALT (PNALT) and platelet (PLT) counts >/=150 000/muL who received liver biopsies were enrolled. HCV carriers with normal serum ALT were divided into four groups according to their ALT levels (/=150 000/muL or <150 000/muL). Results: In 129 HCV carriers with PNALT, the rate of progression of fibrosis stage was 0.05/year and no HCC was detected during the follow up for 10 years. Approximately 20% of patients with ALT /=150 000/muLwere at stage F2-3; however, approximately 50% of patients with ALT /=31 U/L when we focus on the inhibition of the development of HCC.  相似文献   
70.
We successfully implanted coronary stents into refractory reoccluded lesions after failed coronary angioplasty in three patients with acute myocardial infarction (AMI). Lesion location was the proximal left anterior descending coronary artery in two patients and the dominant right coronary artery in one patient. The reference diameters of the lesions were 3.64, 3.33, and 3.50 mm, respectively. A stent with a luminal diameter of 3.0 mm was implanted in all patients. Poststenting dilation of the stent was performed at high pressure (18 atm), and urokinase was administered immediately thereafter. Heparin was administered for 24 h with maintenance of activated coagulation time within 180–200 s. Warfarin was then administered to keep the international normalized ratio within 2.5–3.5. Luminal diameters immediately after stenting were 3.14, 2.89, and 3.26 mm, and those at 1 month after stenting were 3.09, 2.81, and 3.12 mm, respectively, indicating good patency. Our experience in these cases suggests that coronary stenting can be applied after unsuccessful coronary angioplasty in selected patients with AMI. The present report includes informative reference data on diameter, postdilation, adjunctive thrombolytic agent administration, and adequate anticoagulation therapy in coronary stenting in this acute application.  相似文献   
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