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71.
The question of whether thyroxine (T4) and thyrotropin-releasing hormone (TRH) affect mitoses in pituitary thyrotrophs (Tt) and somatotrophs (St) of hypothyroid
rats was investigated. Fifteen day thyroidectomized (Tx) rats were used. Groups of Tx animals received T4 or TRH or both. Except 6 and 24 h TRH groups, the animals were sacrificed 12 h after injections. Unoperated euthyroid rats
served as controls. In Tx group adenohypophysial mitoses were significantly increased. T4 diminished mitoses in Tx rats. Mitotic counts were decreased in 6 and 24 h Tx groups, but increased in 12 h TRH group. TRH
plus T4 in Tx animals had a synergistic effect on adenohypophysial mitoses. In unoperated controls few mitoses were observed in Tt
and more mitoses in St. In Tx rats more mitoses were seen in Tt than in St. T4 alone failed to reduce mitoses in Tt but increased them in St. We concluded that T4 affects Tt and St replication. In normal rats mitoses occur mainly in St. In Tx rats mitotic activity increased in Tt. TRH
plus T4 have a synergistic motogenic effect on St. T4 but not TRH affects St replication. It appears that the presence, of T4 is necessary for St multiplication. 相似文献
72.
采用新近发展的cDNA代表性差异分析法筛选鼻咽癌中不表达的或表达降低的cDNA序列。结果显示:有9个与已知基因高度同源的cDNA序列。通过对这些已知基因的结构和功能分析,发现有与细胞骨架成分相关的基因:αactinin,ezrin和细胞角蛋白13;直接与瘤基因和抑瘤基因相互作用的基因:鲨烯合成酶和TRIP1基因;直接参与DNA合成以及调控基因转录和翻译的基因:TAFⅡ68和组蛋白H10;另外还有人类补体因子B及类转运RNA合成酶的基因。这些基因大多具有相当于抑瘤基因的功能。从而进一步说明鼻咽癌的发生是多基因相互作用的结果。 相似文献
73.
Allergic skin reactions to anticonvulsant medications in patients receiving cranial radiation therapy 总被引:1,自引:1,他引:0
PURPOSE: Erythema multiforme and Stevens-Johnson syndrome have been associated with anticonvulsant medications (AEDs) in patients with brain tumors receiving cranial irradiation. AEDs are also known to cause mild drug rashes. The incidence of these complications has not been well studied among patients with brain tumors. We reviewed the records of patients with brain tumors treated with cranial radiation and AEDs to assess the frequency of both severe and mild skin reactions. METHODS: Retrospective review of 289 radiotherapy records of consecutively treated patients from 1988 to 1993. RESULTS: Only one of 289 patients developed erythema multiforme. Milder rashes, however, occurred in 18% of exposures to AEDs including 22% of exposures to phenytoin, compared with the expected rate of 5-10%. Most of the mild drug rashes occurred before the initiation of radiotherapy, suggesting that radiation was not the cause of these reactions. CONCLUSIONS: Severe skin rashes are rare among patients with brain tumors receiving radiation therapy and AEDs. There is, however, an increased frequency of mild drug rashes among patients with brain tumors that does not appear related to radiation. 相似文献
74.
75.
A. Larena M. Vierbuchen S. Schröder A. Larena-Avellaneda I. Hadshiew R. Fischer 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1996,381(2):102-113
Zusammenfassung In einer immunhistochemischen Arbeit wurden 104 papilläre Schilddrüsenkarzinome auf das Vorkommen von Blutgruppenantigenen des AB0- und Lewis-Systems sowie verwandter, tumorassoziierter Antigene mit Typ-1- und Typ-2-Grundstruktur untersucht. Folgende Strukturen wurden im Gewebe nachgewiesen: CA-50 (sialinierter Typ-1-Vorläufer), CA-19-9 (Sialyl-Lea), Lea, Leb, A, B, H, Lex, Sialyl-Lex und Ley. Während gesundes, adultes Schilddrüsengewebe keine Blutgruppenantigene exprimierte, waren die papillären Karzinome durch die progressive Expression dieser Strukturen gekennzeichnet. Die meisten Tumoren reagierten mit dem C-50-Antikörper (84%), während deutlich weniger Gewebe das CA-19-9-Antigen aufwiesen (38%). Die Typ-2-Strukturen Lex (47%) und Ley (13%) wurden deutlich seltener gefunden als die korrespondierenden Typ-1-Antigene Lea (71%) und Leb (62%). Die Vorbehandlung mit Neuraminidase verstärkte die Lea- und Lex-Färbeergebnisse in 27 bzw. 44 Fällen. Von den A-, B-, und H-Antigenen wurden die A-Determinanten am häufigsten nachgewiesen (24%). In vergleichenden Untersuchungen von Serienschnitten der gleichen Tumoren wurde eine Koexpression mehrerer Typ-1-Antigene im denselben Tumorarealen festgestellt. Karzinome mit Expression von Typ-1- und Typ-2-Strukturen wiesen häufig eine komplementäre Antigenexpression in verschiedenen Bereichen der Gewebe auf. Einige Tumoren exprimierten Typ-1- und Typ-2-Strukturen auch in den gleichen Zellen, jedoch in verschiedenen Bereichen der jeweiligen Zellen.In 68 Fällen wurde eine Follow-up-Untersuchung durchgeführt. Die Beobachtungszeiträume lagen zwischen 12 und 217 Monaten. In 13 Fällen rezidivierte der Tumor, 7 dieser Patienten verstarben an dem Tumorleiden. Die meisten Rezidive traten bei Patienten auf, deren Tumoren die Grenzen des Organs überschritten hatten (pT4, n=19), während keines der pT1-Karzinome (n=20) zu einem Rezidiv geführt hatte. Während Lymphknotenmetastasen in 39 Fällen auftraten, wiesen 6 Patienten Fernmetastasen auf. Die klinischen Ergebnisse wurden mit den Färbeergebnissen korreliert. Es bestand kein Zusammenhang zwischen Antigenexpression und Tumordifferenzierung. Die pT4-Tumoren zeigten eine signifikant stärkere Expression der CA-50-, CA-19-9-, Lea und Sialyl-Lex-Strukturen. Karzinome mit Ley-Expression wiesen signifikant häufiger Metastasen auf. Ley, H-Typ-1 und H-Typ-2 traten häufiger in rezidivierenden Tumoren auf. Im Gegensatz dazu waren alle Patienten, deren Karzinom das A-Antigen exprimierte, fernmetastasen- und rezidivfrei (n=14). In der multiplen Regressionsanalyse wies der Faktor Fernmetastasierung die größte prognostische Relevanz auf, während im Vergleich dazu die Färbeergebnisse statistisch von untergeordneter Bedeutung waren.
Blood group antigen expression in papillary carcinoma of the thyroid — An immunohistochemical and clinical study on the occurrence of Lewis-, AB0, and derived antigens
Nine monoclonal antibodies, lectin from Ulex europaeus and neuraminidase enzyme were employed to demonstrate the occurrence of type 1 and type 2 blood group antigens in 104 cases of papillary carcinoma of the thyroid. The reagents applied, recognize the following blood group related antigens: CA-50 (sialylated type 1 precursor), CA-19-9 (sialylated Lea), Lea, Leb, A, B, H, Lex, sialylated Lex, and Ley.Immunohistochemical studies revealed that papillary carcinoma of the thyroid, in contrast to histologically normal thyroid tissue, is characterised by a progressive expression of blood group antigens. Most tumours (84%) reacted with C-50 antibody, whereas only a minority of the tissues demonstrated the CA-19-9 antigen (38%). Type 2 structures Lex (47%) and Ley (13%) were found less often than their corresponding type 1 isomers Lea (71%) and Leb (62%). Desialylation with neuraminidase increased the Lea and Lex staining intensity in 27 and 44 cases, respectively. of the A, B, H antigens the A determinants encountered most frequently (24%).Comparative examinations of sequential sections of the same tumour revealed coexpression of type 1 antigens in the same areas. In carcinomas showing type 1 and type 2 antigen reactivity, a complementary distribution of the structures in different tumour areas was often demonstrated. Some tumours presented combined type 1 and type 2 antigen expression in the same cells, however, in distinct areas within the cell.A follow-up examination was carried out in 68 of the 104 cases. The observation time ranged from 12 to 217 months. Thirteen patients suffered from recurrence, of which 7 died. While lymphatic metastases occurred in 39 tumours, distant metastases were detected in 6 patients. Most of the recurrences were found in patients with tumour classification pT4 (n=19), whereas none of the pT1 carcinomas (n=20) showed recurrence.The clinical results were compared to the blood group antigen expression results. There was no correlation between antigen expression and differentiation degree of the tumour. The pT4 tumours showed a significant higher expression of the CA-50, CA-19-9, Lea and Sialyl Lex structures. Carcinomas expressing the Ley antigen were associated with a significant higher level of metastasizing capacity. The Ley, H type 1 and H type 2 antigens occurred more frequently in recurrent tumours (n=14). In contrast, none of the patients whose carcinomas expressed the Aantigens (n=14) suffered from a recurrence or hematogenous metastasis.Multiple stepwise regression analysis was carried out to check the importance of each staining and clinical factor. In this analysis, distant metastasis was the most important parameter, whereas the staining results were of minor statistical importance.相似文献
76.
Gerald M. Rittenberg M.D. Stephen I. Schabel M.D. Ivan Vujic M.D. Hubert C. Meredith M.D. 《Skeletal radiology》1978,2(4):243-244
The angiographic analogue of the sunburst, (right angle) periosteal new bone formation in osteogenic sarcoma is described. The angiographic findings in this tumor and their relationship to the pathologic appearance are discussed. 相似文献
77.
D. Ladurner G. Seeber K. Schmid M. Tötsch E. Donnemiller 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1991,376(4):203-207
Zusammenfassung 308 Patienten mit papillärem Schilddrüsenkarzinom (82,6% des Gesamtkrankengutes, Operation 19522–1987), die postoperativ als tumorfrei eingestuft worden waren, wurden retrospektiv analysiert. Die Beobachtungszeit reicht von 1 Monat bis zu 29,4 Jahren (mediane Beobachtungszeit 4,58 Jahre). Bei 32 Patienten (10,4%) wurde ein Tumorrezidiv am Hals diagnostiziert (lokal und/oder regionär). 8 davon sind am Ende der Beobachtungszeit nicht tumorfrei, 6 sind am Tumor verstorben (tumorbedingte Todesrate 18,8%, relative Mortalität 66,7%, im Gesamtmaterial 2,9% bzw. 29,0%). Die kumulative Rezidivwahrscheinlichkeit beträgt 9,98% nach 5 und 16,98% nach 10 Jahren. Die statistische Analyse der Rezidivwahrscheinlichkeit erfolgte nur an Patienten, die mindestens 5 Jahre beobachtet wurden oder innerhalb dieses Zeitraumes verstarben. Als Einflußgrößen wurden neben Alter and Geschlecht, tumorstadium und histologische Kriterien des Tumors berücksichtigt. Als bestimmend für das Auftreten eines Rezidivs nach 5 Jahren Beobachtungszeit erweisen sich der Status der regiondren Lymphknoten, der Differenzierungsgrad des Tumors und das Geschlecht der Patienten. Zur Verbesserung der Rezidivrate wird eine abgestufte therapeutische Radikalität in Abhängigkeit von den Einflußgrößen empfohlen.
Cervical tumour recurrence after papillary thyroid carcinoma. A statistical analysis on the recurrence after potentially curative surgery
Summary 308 cases of papillary thyroid carcinoma (82.6% of our patients operated on between 1952 and 1987) who had undergone potentially curative surgery were analysed postoperatively. The follow-up ranges from 1 month to 29.4 years (median 4.58 years). In 32 cases (10.4%) a cervical tumour recurrence (local recurrence and/or cervical lymph nodes) was found. 8 of these are not free of tumour at the end of the follow-up, 6 had died of thyroid carcinoma (case fatality rate 18.8%, mortality rate 66.7%, in the entire material 2.9% and 29.0% respectively). The cumulative recurrence rate is 9.98% after 5 years and 16.98% after 10 years. A statistical analysis of the probability of recurrence was carried out only for patients who could be followed at least 5 years or those who died within 5 years. Age, sex, stage of tumour and histological criteria were taken into account as statistical variables. The state of cervical lymph nodes, the differentiation of the tumour and the patients' sex turned out to be determining factors for tumour recurrence after 5 years. In order to improve the recurrence rate a differentiated surgical radicality, depending on the above mentioned variables, is recommended.相似文献
78.
Frank C. Marchetta 《Journal of surgical oncology》1981,16(3):229-232
The surgical oncologist is sometimes confronted with a patient who was surgically treated for cancer of the thyroid gland and now has recurrent disease. In most instances, additional surgical treatment is indicated. The magnitude of surgery is primarily determined by the amount of tissue removed at the original operation. Surgery for recurrent disease may include completion of total thyroidectomy with dissection of lymphatic tissues in the thyroid compartment or/and neck dissection, preferably modified. Several clinical situations are outlined and discussed. 相似文献
79.
Monique VizelSchwartz 《Journal of surgical oncology》1981,17(1):57-61
The eighth case of osteoclastome-like giant cell carcinoma of the thyroid, and the first one to be treated with adriamycin in addition to surgery and radiation, is reported. This rare variant of anaplastic thryoid carcinoma appeared in a patient operated on for meningioma and treated for multiple myeloma with cranial radiation and chronic administration of cytoxan. 相似文献
80.
The case of a patient with reappearing stupor, accompanied by auditory hallucinations and persecutory ideas during the periods and not with alternating excitement, is reported. After 24 years of neuroleptics medication with little effect, the lithium carbonate regimen was started, which showed a remarkable prophylactic effect. The implications of lithium carbonate treatment for recurrent psychosis are discussed. 相似文献