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71.
72.
Hepatic angiomyolipoma (AML) is very rare and only about 80 cases have been reported. The tumor is fundamentally heterogeneously composed of the three tissue components of blood vessels, smooth muscle cells (SMC), and fat cells. Two cases of hepatic AML are reported here, both of which are histologically composed predominantly of a fat cell element and resembled true lipoma (lipomatous AML). However, careful examination of both tumors revealed the presence of a small amount of epithelioid SMC, especially around blood vessels. Immunohistochemical study using monoclonal antibody for melanoma (HMB-45) clearly revealed a small amount of HMB-45-positive SMC around the blood vessels and scattered in the diffuse fat cell growth in both tumors. Since no liver tissue components or primary liver tumors are reactive with HMB-45 except AML cells, the presence of HMB-45-positive cells within the tumor clearly established the diagnosis of hepatic AML. Any fatty tumor or focal fatty lesion of the liver that superficially resemble true lipomas should be tested for the presence of HMB-45-positive SMC in the tumor to differentiate it from AML. 相似文献
73.
The molecular basis of cryptorchidism 总被引:14,自引:0,他引:14
74.
Increased aneuploidy in spermatozoa from testicular tumour patients after chemotherapy with cisplatin, etoposide and bleomycin 总被引:7,自引:0,他引:7
De Mas P Daudin M Vincent MC Bourrouillou G Calvas P Mieusset R Bujan L 《Human reproduction (Oxford, England)》2001,16(6):1204-1208
Testicular cancer is the most common neoplasia occurring in the young male population. The PEB (cisplatin, etoposide and bleomycin) adjuvant chemotherapy usually proposed after orchidectomy in non seminomatous tumours, and in metastatic seminomas, has improved the long-term survival of these patients. Following an azoospermic period, sperm cell recovery is generally observed after treatment delivery, but little is known about the genetic consequences on these new spermatozoa. To estimate the chromosomal consequences of this chemotherapy on sperm cells during the period of recovery of spermatogenesis, sperm cell aneuploidy was studied in testicular cancer patients, at 6-18 months after PEB adjuvant chemotherapy delivery, using fluorescence in-situ hybridization (FISH) of chromosomes 7, 16, 18, X and Y with specific DNA probes. A significant increase in the frequency of diploidy and disomy for chromosomes 16, 18 and XY was observed in treated patients compared with a healthy control group. Spermatozoa aneuploidy occurring during the spermatogenesis recovery period might be a possible side effect of the PEB regimen. Thus, practitioners should be advised to provide counselling about the need for an appropriate duration of contraception. Moreover, genetic counselling should be offered in cases of pregnancy occurring soon after the end of chemotherapy. 相似文献
75.
Diffuse sclerosing variant of papillary thyroid carcinoma: A clinicopathologic and immunophenotypic analysis of 22 cases 总被引:3,自引:0,他引:3
Background: The diffuse sclerosing variant of papillary thyroid carcinoma (DSV-PTC) is an uncommon tumor making up about 2% of all papillary
thyroid carcinomas. Previous studies have not comprehensively evaluated these tumors in a large series of patients.
Design: Twenty-two cases of DSV-PTC diagnosed between 1970 and 2000 were identified in the files of the AFIP. Histologic and immunohistochemical
features were evaluated and patient follow-up was obtained.
Results: The tumors affected 14 females and 8 males, aged 6 to 49 yr (mean, 18 yr), with males presenting at a mean older age than
females (24 vs 14 yr). Symptoms included an enlarging mass in the thyroid, present for a mean of 9.5 mo. While a dominant
tumor was identified in a single lobe, bilateral disease was common (n=16). The dominant mass ranged in size from 1.7 to 5.8 cm in diameter (mean, 3.8 cm). Histologically, all cases demonstrated
a papillary carcinoma (conventional, solid, or follicular pattern) diffusely involving the gland. Extrathyroidal extension,
lymphocytic thyroiditis, squamous metaplasia, increased fibrosis/sclerosis, and psammoma bodies were present to a variable
degree. Both the papillary carcinoma and squamous metaplasia cells were strongly immunoreactive with CK19, thyroglobulin,
and TTF-1. An increased number of S-100 protein immunoreactive dendritic cells were recognized. p53 was increased (>15%) in
the tumor cells in 12 patients, while Ki-67 was increased in the tumor cells in two patients. Perithyroidal and cervical lymph
node metastasis occurred in 18 (82%) patients. All metastases demonstrated histologic features similar to the primary. Complete
resection (thyroidectomy in 18 patients) with lymph node dissection, yielded a 95% 5-yr survival without evidence of disease.
One patient died of disease after a malignant transformation of the squamous metaplasia into squamous cell carcinoma.
Conclusions: The recognition of DSV-PTC can be made with the following features: classic to solid foci of PTC, lymphocytic thyroiditis,
squamous metaplasia, increased fibrosis, and innumerable psammoma bodies. DSV-PTC is more biologically aggressive than conventional
PTC, but the patients’ survival is not significantly different. This diagnosis should lead the clinician to aggressively manage
these patients (thyroidectomy and lymph node dissection) in an effort to achieve an excellent long-term clinical outcome. 相似文献
76.
We report two cases of infertility treatment in couples where males suffered from Kartagener's syndrome (KS) and a total absence of motile sperm in the ejaculate. A total of three ICSI cycles was carried out. In all cycles, viable ejaculated or testicular spermatozoa were selected using the hypo-osmotic swelling (HOS) test. Case 1: In the first ICSI cycle total fertilization failure occurred after using ejaculated spermatozoa. In the following cycle testicular spermatozoa were used for ICSI, resulting in 75% fertilized oocytes and a pregnancy. Case 2: In the same ICSI cycle 50% of the oocytes were injected with ejaculated and 50% with testicular spermatozoa. The fertilization rates were 44 and 56% respectively and high quality embryos were achieved in both groups. One single embryo derived from testicular sperm was transferred with a resulting singleton pregnancy. In conclusion, testicular sperm for ICSI seem to have reliable fertilization capacity in men with KS, while ejaculated sperm, even if tested viable, seem more unpredictable. HOS test for selection of viable sperm for ICSI is recommended when ejaculated as well as testicular sperm are used for ICSI. 相似文献
77.
The aim of this study was to investigate the possible correlation between the 1H MRS mobile lipid signal, necrosis and lipid droplets in C6 rat glioma. First, the occurrence of necrosis and lipid droplets was determined during tumor development, by a histological analysis performed on 34 rats. Neither necrosis nor lipid droplets were observed before 18 days post-implantation. At later stages of development, both necrosis and lipid droplets were apparent, the lipid droplets being mainly located within the necrotic areas. Using a second group of eight rats, a temporal correlation was evidenced between mobile lipid signal detected by in vivo single-voxel one- (136 ms echo time) and two-dimensional J-resolved 1H MR spectroscopy, and the presence of necrosis and lipid droplets on the histological sections obtained from the brains of the same rats. Finally, spatial distribution of the mobile lipid signal was analyzed by chemical-shift imaging performed on a third group of eight animals, at the end of the tumor growth. The spectroscopic image corresponding to the resonance of mobile lipids had its maximum intensity in the center of the tumor where necrotic regions were observed on the histological sections. These necrotic areas contained large amounts of lipid droplets. All these results suggest that mobile lipids detected in vivo by 1H MRS (136 ms echo time) in C6 rat brain glioma arise mainly from lipid droplets located in necrosis. 相似文献
78.
Summary Preparations of 75–80% pure Leydig cells are prepared by Percoll gradient centrifugation of crude testicular interstitial cell suspensions. Using the methods described herein, the purified Leydig cells retain their functional characteristics for at least 72 hours in primary culture. 相似文献
79.
Retrospective multicentre study on mechanical and enzymatic preparation of fresh and cryopreserved testicular biopsies 总被引:1,自引:0,他引:1
Baukloh V;German Society for Human Reproductive Biology 《Human reproduction (Oxford, England)》2002,17(7):1788-1794
BACKGROUND: Isolation of sperm suitable for ICSI from fresh or frozen-thawed testicular sperm extraction (TESE) can be facilitated by mechanical or enzymatic processing of the samples. METHODS: A retrospective multicentre study was initiated to compare these two approaches. Eleven German centres provided data on their TESE cycles performed during the period 1996/1997. Quality of retrieved sperm, fertilization rates of injected oocytes, embryo quality, resulting pregnancy rates and evolution of pregnancies were evaluated. RESULTS: The percentage of cycles with at least some motile sperm available for injection was higher after mechanical preparation. Independent of the preparation method, fertilization rates were higher for motile compared with immotile sperm or elongated spermatids in all groups and in general higher for cryopreserved versus fresh samples. Embryo quality was significantly better after injection of motile sperm for all treatments and in particular after enzymatic versus mechanical processing of biopsies. Pregnancy rates were identical for embryos derived from sperm prepared mechanically or enzymatically from fresh or cryopreserved testicular samples. The abortion rate (32/172, 18.6%) and the rate of multiple implantations (32/140, 22.9%) were not different from results reported in the literature for ICSI using ejaculated sperm. CONCLUSION: In this retrospective multicentre study, no unequivocal advantage of one over the other preparation method could be identified in 839 ICSI cycles using testicular sperm from 549 patients. 相似文献
80.