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61.
A clinical, pathologic, and molecular virologic analysis of 30 cases of invasive squamous cell carcinoma of the vulva was undertaken to investigate the relationship of human papillomavirus (HPV) to this neoplasm. The presence of the virus was detected by the polymerase chain reaction and localized in the tumor and in the adjacent epithelium by in situ hybridization of paraffin sections of vulvectomy specimens. Specimens were examined for nucleic acid sequences of HPVs 6, 11, 16, and 18 were detected by in situ hybridization utilizing 35S-labeled antisense RNA probes and by polymerase chain reaction using HPV type-specific primers for a segment of the E6 gene followed by Southern hybridization of the amplified products. The cases were classified as typical squamous cell carcinoma, basaloid carcinoma, and warty carcinoma. Typical squamous cell carcinoma shows varying degrees of squamous maturation, whereas basaloid carcinoma is characterized by immature basal-type cells showing minimal or no squamous maturation. Warty carcinoma displays an exophytic condylomatous appearance. The squamous cells of this tumor are mature, and many show koilocytotic atypia characterized by a variable degree of nuclear atypia and cytoplasmic vacuolization. The adjacent epithelium was classified as squamous hyperplasia, lichen sclerosus, or vulvar intraepithelial neoplasia (VIN). VIN was subdivided into basaloid or warty VIN using similar criteria as for the invasive carcinomas. Overall, HPV 16 was detected in 11 cases and HPV 18 in two; none of the cases were positive for HPVs 6/11. HPV was detected in four (21%) of 19 squamous cell carcinomas, six (75%) of eight basaloid carcinomas, and three (100%) of three warty carcinomas. The adjacent epithelial lesions also showed a close correlation with the tumor type and presence of HPV. Fourteen (74%) squamous cell carcinomas had adjacent squamous hyperplasia; all of these squamous hyperplasias were negative for HPV. In contrast, seven (87%) of the basaloid carcinomas had adjacent basaloid-VIN and HPV 16 was detected within the VIN in three. Three warty carcinomas (100%) had adjacent warty VIN or basaloid VIN, and HPV was detected within VIN in two. The mean age of women with squamous cell carcinoma was 77 years, for women with basaloid carcinoma 54 years, and for those with warty carcinoma 47 years. The mean age of women with HPV-negative tumors was 77 years compared with 55 years for women with HPV-positive tumors (p less than 0.01). Thus, there appears to be a close correlation between the presence of HPV, specific subsets of invasive carcinoma and VIN, and age.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
62.
Cervical condylomas and intraepithelial neoplasia (CIN) were correlated with human papillomavirus (HPV) types and analyzed for the presence of abnormal mitotic figures. Colposcopically directed cervical biopsies were divided in half and processed for routine microscopy and Southern blot hybridization. Of 83 specimens from 71 patients, 70 (84%) contained HPV-DNA sequences. The HPV distribution was as follows: HPV 16 in 6/25 flat condylomas (FC), 2/8 CIN I, 8/18 CIN II, 12/14 CIN III; HPV 18 in 1/25 FC; HPV 31 in 3/25 FC, 3/18 CIN II, and 1/14 CIN III; HPV 6/11 in 12/18 exophytic condylomas (EC), 5/25 FC, 2/8 CIN I, and 3/18 CIN II. Uncharacterized HPVs were identified in 4/18 EC, 5/25 FC, 2/8 CIN I, and 1/18 CIN II. A similar heterogeneous distribution of HPV types was found in flat condylomas and CIN I. A more homogeneous distribution was noted in the exophytic condylomas and high grade CIN lesions, with HPV 6/11 found in the former and predominantly HPV 16 in the latter. Abnormal mitotic figures were predominantly seen in the high grade CIN lesions. Based on our findings, we would recommend that the term flat condyloma be abandoned and that low grade flat lesions of the cervix be graded according to CIN criteria.  相似文献   
63.
Restriction enzyme digestion and Southern blot hybridization were used to analyze deoxyribonucleic acid (DNA) extracted from exfoliated cervical cells for the presence of human papillomavirus sequences and these results were correlated with cytologic findings on Papanicolaou smears. Specimens (N = 204) were obtained from a nonselected population of women undergoing routine cytologic screening and human papillomavirus DNA sequences were detected in 33 (16%) women. Thirteen smears contained atypical squamous cells, ranging from very mild dysplasia to moderate dysplasia; all showed associated morphologic evidence of human papillomavirus infection characterized by koilocytosis, nuclear enlargement, wrinkling, and hyperchromasia, and human papillomavirus DNA was demonstrable in 12 (92%) smears. Of the remaining 191 samples with normal cytology, 21 (11%) also contained human papillomavirus DNA sequences. Reevaluation of the smears from these women resulted in a revision of the cytologic diagnosis to very mild dysplasia in four cases. These data suggest that human papillomavirus infection occurs more frequently than predicted by cytologic screening.  相似文献   
64.
This report presents preliminary observations on the immunocytochemical localization of human chorionic gonadotropin (hCG) and human placental lactogen (hPL) in placental site trophoblastic tumors, hydatidiform moles, and choriocarcinomas and compares the findings with those of a similar immunocytochemical analysis of the placenta at various stages of development. In addition to cytotrophoblast (CT) and syncytiotrophoblast (ST), a third form of trophoblast designated "intermediate trophoblast" (IT) is present during normal pregnancy and in trophoblastic disease. Intermediate trophoblastic cells are mononucleate, larger than CT, and contain more abundant eosinophilic cytoplasm, resulting in a partial resemblance to ST. Intermediate trophoblast has distinctive immunocytochemical features that distinguish it from CT and ST. The localization of hPL and hCG in both IT and ST varies with the age of the placenta, with the type of trophoblastic neoplasm, and from one specimen to another within each category of tumor. Syncytiotrophoblast may contain both hormones in large amounts, whereas IT contains hPL predominantly and hCG focally. Cytotrophoblast is devoid of hCG and hPL except in choriocarcinoma, which may show focal weak staining for hCG. Immunocytochemical identification of hCG and hPL has proved helpful in clarifying the histogenesis of trophoblastic neoplasms and may also be of value in establishing their diagnosis and in determining their prognosis.  相似文献   
65.
The majority of breast cancer research is conducted using established breast cancer cell lines as in vitro models. An alternative is to use cultures established from primary breast tumours. Here, we discuss the pros and cons of using both of these models in translational breast cancer research.  相似文献   
66.
Paracetamol is the commonest agent employed in self poisoning, however it is not clear whether adolescents possess insight into the serious complications associated with its misuse. Using a one page questionnaire, the availability, usage, and knowledge of toxicity of paracetamol among 1147 American and British adolescents was assessed. Although 90% of all students recognised that paracetamol could kill, the great majority of students overestimated the lethal dose. In addition, while knowledge regarding side effects of paracetamol was poor the drug was widely available to, and used by, the study population. It is proposed that gross overestimation of the number of tablets required to kill, poor understanding of paracetamol side effects, and wide availability of the drug contribute to its frequent use in adolescent suicidal behaviour. The inclusion of some over-the-counter medications in school drug education programs in addition to tighter control of the availability of paracetamol may help reduce the problem of adolescent self poisoning.  相似文献   
67.
The main purpose of this study was to compare rectal and axillary temperature measurements in African children. Altogether 573 sick children were seen in an outpatient setting in rural West Africa. Rectal and axillary temperatures were measured and the parent or guardian was asked if they thought that the child had a raised body temperature. Normal ranges were defined from an age matched population of 203 healthy children. A raised axillary temperature predicted a raised rectal temperature with a sensitivity of 98% and a specificity of 88%. The parents' impression that their child had a fever was a less sensitive (89%) and less specific (59%) indicator of raised rectal temperature. A raised axillary temperature is a good screening test for a raised rectal temperature in African children.  相似文献   
68.
Doppler and direct measurements of right ventricle to right atrial pressure drop were made during cardiac catheterisation on 28 occasions in 26 infants with congenital heart disease. Age was 10 days to 12 months (median 4.5 months), and weight was 3.1 to 9.0 kg (median 4.7 kg). We measured peak velocity of tricuspid regurgitation by continuous wave Doppler, and the pressure drop was calculated using the modified Bernoulli equation (delta p = 4v2). There was a high correlation (r = 0.95) between direct and Doppler measurements. Doppler values tended to underestimate the right ventricle to right atrial pressure drop, but this was not of clinical significance (mean 2 mm Hg). The 95% confidence interval for the Doppler velocity was -0.41 to +0.26 m/sec, and was consistent across the range of pressures studied. Variability between observers was tested, by two observers performing sequential paired examinations on 16 newborn babies with tricuspid regurgitation. The coefficient of repeatability was 6.3 mm Hg (95% confidence interval 4.7 to 9.5 mm Hg) or 0.26 m/sec (0.18 to 0.50 m/sec). This method of right ventricular pressure estimation, validated previously only in older children and adults, is a reproducible and accurate technique in infants with tricuspid regurgitation.  相似文献   
69.
O'Meara A, Tormey W, Fitz Gerald RJ, Fitzgibbon M, Kenny D. Interpretation of random urinary catecholamines and their metabolites in neuroblastoma. Acta Paediatr 1994;83:88–92. Stockholm. ISSN 0803–5253
This study reports experience in the estimation of urinary catecholamines (uCATs) and their metabolites in the diagnosis and follow-up of neuroblastoma. Random urine samples were assayed for dopamine, noradrenaline and adrenaline, together with their metabolites 4-hydroxy 3-methoxyman-delic acid (HMMA) and homovanillic acid (HVA), using HPLC with electrochemical detection. Twenty of 21 patients had elevation of one or more uCATs metabolites at diagnosis. Patients were monitored serially from diagnosis and, in those patients who had delayed resection of primary tumour (n=13), particular attention was paid to levels at the pre-surgical evaluation as an indicator of persistence of viable disease at the time of surgery; dopamine proved to be the most accurate indicator of persistent disease at this time. Five of these patients developed recurrent disease, 4 of whom had elevation of two or more uCATs metabolites at the time of relapse. Several conclusions can be drawn from this study: (a) results for HMMA, HVA and dopamine in random urine samples will detect all but the most biochemically immature or inert tumours; (b) dopamine may be the most reliable indicator of persistent disease and (c) noradrenaline and adrenaline measurements were of little benefit. As results are Expressed in relation to urinary creatinine, excretion of which may be affected by dietary protein and is therefore not constant, borderline results should be repeated.  相似文献   
70.
A 4 year old girl treated with a standard chemotherapy protocol for acute lymphoblastic leukaemia developed hepatic candidosis during the consolidation phase. This relapsed after a prolonged course of amphotericin B and flucytosine. An eight week course of liposomal amphotericin produced a marked clinical improvement which was sustained for one year. A subsequent relapse was associated with transformation to myelodysplastic leukaemia.  相似文献   
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