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991.
The sweat test was performed by the method of Gibson and Cooke on 36 children with second and third degree malnutrition, aged from 2 months to 4 years. The results were compared with those from 32 healthy, well nourished controls in the same age range. Determinations were made of sodium and chloride concentrations, chloride/sodium ratio, and the sum of the concentrations of the two electrolytes in each sample. The malnourished children were found to have higher sodium and chloride concentrations than the well nourished ones. None of the normal or malnourished children had a sweat chloride value greater than 60 mmol/l; chloride values within a suspicious range (between 40 and 60 mmol/l) were found in two malnourished children. Two well nourished controls and six malnourished children showed suspicious sweat sodium concentrations; in one child with third degree malnutrition the sodium content was greater than 60 mmol/l. In all results in the suspicious range, or greater than 60 mmol/l, the chloride/sodium ratio was less than 1, and the sum of the two electrolytes was below 140 mmol/l. Based on these results, we conclude that malnourished children have raised sweat sodium and chloride concentrations when compared with well nourished children. The electrolyte values for most of them are not in a suspicious range or consistent with a diagnosis of cystic fibrosis. Unlike that found in cystic fibrosis, the sodium/chloride ratio in our subjects was less than 1 and the sum of both electrolytes never exceeded 140 mmol/l.  相似文献   
992.
993.
Arterial oxygen tension was measured from radial artery samples in 276 infants referred for cardiological investigation. Values obtained during air breathing in infants with congenital heart disease showed considerable overlap between 'cyanotic' and 'acyanotic' groups, and are of limited diagnostic use. By contrast, values obtained while breathing oxygen in concentrations of over 80%, measured in 182 infants, allowed clear differentiation between these groups. All infants with acyanotic, but only 2 of 109 with cyanotic lesions, achieved an arterial oxygen tension of more than 150 mmHg. In the cyanotic group the response to oxygen breathing was significantly greater in common mixing situations and in the hypoplastic left heart syndrome than with either pulmonary outflow tract obstruction or transposition of the great arteries. Infants with transposition had a significantly lower mean arterial oxygen tension in air than infants with other forms of cyanotic congenital heart disease. Of 23 infants whose final diagnosis was primary lung disease but in whom cyanotic congenital heart disease had been suspected, 7 achieved arterial oxygen tensions of more than 150 mmHg during oxygen breathing, and on this basis cardiac catheterization was not performed. We therefore conclude that measurement of the arterial oxygen tension while breathing high concentrations of oxygen should be routinely performed in the initial assessment of sick infants with suspected congenital heart disease.  相似文献   
994.
Pretreatment diagnosis of lymphatic involvement and evaluation of its extent are important in patients with carcinoma of the uterine cervix. From April 1973 to December 1974 all Stage I and II patients with histologically confirmed carcinoma of the cervix at Walter Reed Army Medical Center who were good operative risks underwent pretreatment lymphangiography. A total of 60 patients was studied. Clinical Stage I patients with negative nodes underwent Wertheim-Taussig hysterectomy. Stage II patients with negative lymphangiograms received radiation therapy. All patients with positive lymphangiograms underwent exploratory laparotomy providing histologic correlation and received appropriate postoperative radiotherapy.Histologic correlation with negative lymphangiograms was found in 94.1% of cases. All nodal metastases 1 cm or greater were identified radiologically, thus permitting a more rational selection of patients for surgical staging and enabling the precise direction of therapy.The results of this study suggest a definite role for lymphangiography as an adjunct in diagnosis and planning therapy in patients with carcinoma of the uterine cervix. It would appear especially useful in the selection of those patients who might benefit from removal of bulky metastases and extended field irradiation.  相似文献   
995.
The objective of the present experiments was to establish an acceptable standard for the cervical mucus penetration test (CMPT) by determining the minimal progressive motile spermatozoa concentration (PMSC) that will yield the highest score for proven fertile donor sperm specimens. For this purpose, fresh and frozen-thawed samples were used. Semen was obtained from 29 fertile donors and different PMSC (8, 10, and 14 x 10(6)/mL) were prepared for each sample. The same mucus specimen was used for testing each sperm sample in the three different dilutions. No difference in the scoring of the CMPT between the fresh vs. frozen-thawed groups was found. When PMSC of 14 x 10(6)/mL was used, almost all specimens scored the highest rank. The present study revealed that only semen samples with a minimal PMSC of 14 x 10(6)/mL cells can be used in the CMPT. The information that the freeze-thaw process does not affect the CMPT results supports the concept of cryopreservation of pooled fertile donor specimens in aliquots with adequate concentration of progressive motile spermatozoa for later use as a CMPT control.  相似文献   
996.
The sagittal split ramus osteotomy is the most commonly used procedure to reposition the mandible surgically. Because it is more technically difficult and associated with a higher incidence of complications compared with other mandibular osteotomies, thorough knowledge of the anatomy of the mandibular ramus is a prerequisite. Anatomic measurements related to the mandibular foramen were obtained from 57 formalin-preserved non-Asian hemimandibles. As shown in previous reports, great variability was noted in the position of the mandibular foramen. However, these studies utilized Asian mandibles with a clear discrepancy in key anatomic measurements in comparison with the authors' data. This brings into question the validity of these earlier studies when applying their data to non-Asian groups. The "fade-out" point of the internal oblique ridge was found not to be a reliable anatomic reference for placement of the horizontal osteotomy along the medial ramus. Thus, familiarity with the described relationships of the mandibular foramen will assist in performing properly a sagittal split of the ramus and will reduce the chance for an unfavorable split.  相似文献   
997.
998.
Histamine is involved in different physiological and pathological responses, such as immune response, gastric acid secretion or neurotransmission, as either angiogenesis or cancer. Histidine decarboxylase (HDC) catalyzes the formation of histamine from histidine. HDC has been suggested as a new marker for neuroendocrine differentiation, inflammatory pathologies and several leukemia and highly malignant forms of cancer, such as melanoma and small cell lung carcinoma. In the present work, we describe the use of Syber Green-based quantitative real-time RT-PCR to determine the expression of histidine decarboxylase in human cells and tissue. As an internal control, glyceraldehyde 3-phosphate dehydrogenase was also amplified. The linear dynamic range of the assay covered 4 orders of magnitude for HDC amplification. The detection limit was 0.1 ng of total RNA extracted from HMC-1 cells. This method is simple, rapid, sensitive, and quantitative, and allows for the specific identification of cells and tissue expressing HDC, stressing its potential diagnostic usefulness in malignancies in which HDC is described as a new marker.  相似文献   
999.
PURPOSE: To summarize the study design of the Multi-Ethnic Pediatric Eye Disease Study (MEPEDS). METHODS: The objectives of the MEPEDS are to: (1) estimate age- and ethnicity-specific prevalence of strabismus, amblyopia, and refractive error; (2) evaluate the association of selected risk factors with these ocular disorders; and (3) evaluate the association of ocular conditions on limitations in health-related functional status in a population-based sample of 12,000 children aged 6-72 months from four ethnic groups--African-American, Asian-American, Hispanics/Latinos and non-Hispanic White. Each eligible child undergoes an eye examination, which includes an interview with his/her parent. The interview includes an assessment of demographic, behavioral, biological, and ocular risk factors and health-related functional status. The examination includes fixation preference testing, visual acuity, stereoacuity, axial length measurement, cycloplegic refraction, keratometry, eye alignment, and anterior and posterior segment examination.  相似文献   
1000.
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