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91.
92.
INTRODUCTION: Acute parvovirus B19 infection induces a transient inhibition of erythroid cell formation, which may induce an erythroblastopenia crisis in patients suffering from chronic hemolytic anemia. EXEGESIS: We report here an exceptional observation of acute erythroblastopenia crisis with good outcome, occurring at the same time in a mother and her son, both suffering from hereditary spherocytosis. Diagnosis of parvovirus infection is based on detection of serum parvovirus B19-specific immunoglobulin M antibodies in the mother and her son and by the positivity of parvovirus B19 DNA detected by PCR in serum in the mother. Outcome was good, with the end of the erythroblastopenia crisis obtained 7 to 10 days later, but requiring blood transfusion in the mother. CONCLUSION: Our observation is a reminder that the contagiosity of parvovirus B19 is high in household contacts and that protection of family members should rapidly be considered in hereditary spherocytosis.  相似文献   
93.
Weaver  DA; Hei  TK; Hukku  B; McRaven  JA; Willey  JC 《Carcinogenesis》1997,18(6):1251-1257
To establish a cell culture model for lung carcinogenesis, independent populations of the human papillomavirus 18-immortalized human bronchial epithelial cell line BEP2D were treated with high linear energy transfer radon-simulated alpha-particles, expanded and xenotransplanted into Nu/Nu mice. Six independent cell lines were established from tumors that developed from three separate radiation treatments as follows: treatment (Tx) 1 (30 cGy--two doses), H2BT, Tx 2 (30 cGy-- single dose), R30T1L, R30T2 and R30T3L, Tx 3 (30 cGy--single dose), H1ATN and H1ATBA1. Cytogenetic analysis revealed common changes in all tumor lines: loss of the Y chromosome (ch), one of three copies of ch8, one of three copies of ch14, and one of two copies of ch4p16-pter and ch11p15-pter. Analysis of polymerase chain reaction-amplified short tandem repeats of informative loci confirmed the loss of chY in all lines and loss of heterozygosity (LOH) at eight loci spanning the length of ch8 in all lines from Tx's 1 and 2. Our data support previous studies indicating the presence of tumor suppressor genes on ch8. LOH also was confirmed on ch14 at locus D14S306 in all cell lines from Tx 2 and in one of two lines from Tx 3. This region, 14q12-q13, may contain changes in one of the five known somatostatin receptor genes (SSTR1). No LOH was detected at any of the informative loci tested for on ch4 or ch11.   相似文献   
94.
Childhood tuberculosis is perceived by many as a disease of the past. Experience in a children's hospital serving a deprived population suggested that tuberculosis and other mycobacterial infections were not declining in clinical practice. Fifty three tuberculous and 11 atypical mycobacterial infections were identified between 1978 and 1992. There was no decline in tuberculosis and nine of the 11 atypical infections occurred in the last five years. Altogether 40% of cases of tuberculosis were in non-Asian children; 32% had arrived in the UK or visited family overseas in the previous year; and 38% had a history of tuberculosis contact, usually a close adult relative. Nationally, the previous decline in tuberculosis in all ages has reversed. In the local health districts in London's east end, childhood tuberculosis has also stopped declining and seems to be increasing. It is regrettable that BCG vaccination has been abolished by some districts in the UK, against current recommendations. Childhood tuberculosis is still common in the practice described here, including among children who do not fall into conventionally recognised high risk groups. Inner city dwellers and junior doctors are both highly mobile populations, adding to the risk that paediatricians, particularly those in training, may encounter tuberculosis with little or no previous experience of the condition.  相似文献   
95.
Zusammenfassung An einem Geschwisterpaar wird der Symptomenkomplex der schweren Cystein-Cystin-Stoffwechselstörung beschrieben. Es sind die ersten Fälle dieser Art, bei welchen die Diagnose intravital gestellt worden ist (bei dem älteren Kind durchE. Freudenberg). Während das eine Kind ein typisches Krankheitsbild mit Nephritis, rachitischen Knochenveränderungen, Anorexie und Zwergwuchs darbietet, zeigt das andere bei einem ähnlichen Nierenschaden und ebenfalls rachitischen Knochenveränderungen völlig normale Gewichts- und Größenentwicklung. Beim erstgenannten Kinde tritt die Rachitis in ihrer atrophischen Form in Erscheinung, beim anderen in der floriden.Es werden die kausalen Zusammenhänge der einzelnen Symptome der renalen Rachitis und des renalen Zwergwuchses besprochen. Aus den eigenen Beobachtungen wird als Beitrag zu dieser noch nicht völlig geklärten Frage gefolgert, daß die wachstumshemmende Kraft des Cystins, wie sie aus den Tierversuchen vonDornuf ersichtlich ist, beim Menschen offenbar nur zusammen mit einem anlagemäßig schwachen Wachstumstriebe ihre Wirkung entfalten kann.Für die Therapie wird neben einer gelockerten Nierendiät die UV-Bestrahlung und D-Vitaminbehandlung trotz entgegenlautender Angaben anderer Autoren empfohlen. Mit der Verabreichung von Hefe bei basenreicher Kost ist ein Versuch gemacht worden.Mit 10 Textabbildungen.  相似文献   
96.
97.
Multisection, dual-echo magnetic resonance (MR) transaxial images of blood vessels contain both anatomic and qualitative information about flow. Even so, the images are produced as a series of two-dimensional tomographic sections from which full visualization of connected structures is difficult. A computer algorithm was developed that automatically detects flowing blood based on pixel intensity and calculated T2 and provides reconstructed views of vessels while analyzing and displaying flow characteristics. Images of abdominal vessels, aortic aneurysms, and the heart were encoded by flow and color to demonstrate depth. In addition, these data were reconstructed to derive a more accurate assessment of patency. With this technique, transaxial images can be used to analyze flow patterns, determine patent areas, and visualize all levels of vessels in a single image.  相似文献   
98.
Background Parathyroid carcinoma (PC) mimics benign primary hyperparathyroidism (PHP), but the diagnosis of PC is seldom available at the time of the first operation. Because PC is plagued by recurrences usually beyond cure, one may wonder whether some of these could be prevented by more extensive resections initially, i.e., if the diagnosis of PC were available at that time.Methods Over a 25-year period, 311 consecutive patients with PHP underwent operation in our department: 302 had benign disease (adenomas or hyperplasias), and 9 had PC. Several clinical parameters, serum calcium and parathyroid hormone (PTH) levels, and the weight of the parathyroid tumor removed were compared in both groups. Receiver operating characteristic curves and logistical regression analyses were used to distinguish PC from benign PHP.Results Eight of 9 patients with PC had symptoms, versus 238 (79%) of 302 with benign PHP (not significant). In the PC subgroup, serum calcium and PTH levels and the tumor weights of the parathyroid glands removed were significantly higher than in the benign PHP cohort, even if these three parameters were regularly flawed by low positive predictive values (14%, 20%, and 15%, respectively).Conclusions Serum calcium, PTH levels, and tumor weights were significantly greater in the PC subgroup, even if not invariably in a discriminatory way. However, when PTH is <4 times the upper limit of normal and tumor weight is <1.9 g, the probability of PC is nil.  相似文献   
99.
100.
BACKGROUND: We aimed to test children with developmental dyslexia for possible alterations of their spatial and visuoperceptual ability. METHODS: A total of 31 children with developmental dyslexia were included in the study. All children underwent a complete ophthalmological and orthoptic examination. Neuropsychological testing was performed using the Visual Object and Space Perception Battery (VOSP) and the subtest "Gestalt Closure" of the Kaufman Assessment Battery for children. Even though the VOSP is validated and standardized for adults, no normal values for children exist thus far. Therefore, a sex- and age-matched control group was tested. In addition, the parents of the dyslectic children completed the Child Behavior Checklist for Ages 4-18 (CBCL/4-18). RESULTS: All children presented normal ophthalmological and orthoptic findings. Performance in the VOSP subtests "progressive silhouettes test'" and "number location" was significantly reduced in dyslectic children when compared to controls ( p<0.0003 and p<0.046, respectively). There was also a tendency towards lower values in the subtest "position discrimination" ( p=0.07). In the other subtests no significant difference between dyslectic children and controls was observed. The results of the subtest "Gestalt Closure" of the K-ABC and the CBCL/4-18 were within normal ranges. CONCLUSION: The study demonstrates that developmental dyslexia is not based on ocular deficits, but indicates possible disturbances of visual-spatial cognition and visual-spatial perception in dyslectic children.  相似文献   
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