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Most geologists believe that there are no Early and Middle Triassic strata in the W. Gandise stratigraphic subregion, but the present authors have found Early Triassic conodonts for the first time in the Shiquanhe area, including five conodonts genera (Form genera): Pachycladina, Neohindeodella, Cornudina, Hadrodontina and Hibbardella sp. etc. Then we affirm that Early Triassic deposits exist in the Gandise stratigraphic subregion, and establish the Tangnale Formation. The conclusion is new important complementary basal data for Triassic stratigraphy division of Gangdise, reconstructing palaogeography and studying Gangdise from Paleozoic to Mesozoic island-arc evolution and transition.

The Angjie Formation and Xiala Formation, present in the Shiquanhe area of Gar County in the western part of Gangdise, Tibet, belong to the Gangdise stratigraphic subregion. Conodonts have been found in the Angjie Formation, and they permit an age determination of Early to Middle Permian for that formation. The age of the Xiala Formation could be late Middle Permian. Whether the Late Permian marine deposits are present in this area still needs to be determined, but it is possible that the lower part of the Xiala Formation overlaps partly the upper part of the Angjie Formation. More importantly, the study has brought about a finding of typical peri-Gondwana cool water facies conodonts, namely, Vjalovognathus sp. nov. x. This is the first report and brief description of a conodont fauna from peri-Gondowana cool water facies in China. It indicates that the Gangdise stratigraphic subregion can be subdivided; the western part belongs to peri-Gondwana cool water facies, and the eastern part belongs to Tethys.

The value of combined application of both ECG-gated cine MRA and 3D-CEMRA in the detection of large intracranial aneurysms was evaluated and the findings were compared with those of conventional MRA and DSA. Twenty-four patients with 26 large intracranial aneurysms underwent MRI and DSA. All these aneurysms, diameter from 15 to 39 mm, were located at internal cerebral artery (n=12), vertebral artery (n=3), basilar artery (n=4), anterior cerebral artery (n=2), middle cerebral artery (n=2), anterior communicate artery (n=2) and posterior communicate artery (n=1). Thirteen cases of hematoma or cavernoma were studied as control group. All patients were examined on GE 1.5T MR system. ECG-gated cine MRA was performed with 2D multi-phase fast gradient-recalled echo sequence in a single section. All the images were analyzed with signal intensity VS time curve for differentiating intraaneurysmal blood flow from static tissue. The results were analyzed by statistic "t" test. 3D-CEMRA was performed with spoiled gradient-recalled echo and one dose of Gd-DTPA. All data was processed with multi-plannar reformat (MPR) and tomography for the demonstration of aneurysms in detail. All 26 aneurysms were demonstrated successfully by combined application of both cine MRA and 3D-CEMRA. Compared to DSA and conventional 3D-MOTSA, its sensitivity and specificity figures were both 100%. Cine MRA could differentiate the blood flow from the static tissue. The intensity VS time curves of intraaneurysmal blood flow offered fluctuating form and average signal change between systole and diastole period was about 89.8 +/- 37.4; However, under the control group, intraaneurysmal thrombus or cerebral hemorrhage or cavernomas had no significant signal change and the curves offered steady form with the average signal change being about 8.2 +/- 6.3. There was statistically significant difference between the intraaneurysmal blood flow and static tissue (P=0.025,0.05). 3D-CEMRA was very useful in demonstrating the aneurysmal size, intraaneurysmal thrombus formation, neck and the detailed relationship of the aneurysm to the surrounding structures. It was concluded that the combined application of both cine MRA and 3D-CEMRA might be a valuable clinical tool for the detection of large intracranial aneurysms.

Conodonts are most important for the study of the Frasnian/Famennian Late Devonian mass extinction and recovery. Conodont mass extinction occurred stepwise (poly-episodes) in the latest Frasnian (latelinguiformis Zone) and was of very short timespan and global scale. Five steps of the conodont mass extinction can be recognized, with the same as in other sections in the world. Conodont recovery occurred in the earliest Famennian marked by the first appearance ofPalmatolepis triangularis. The timespan of the conodont recovery interval can be estimated as much less than 0.5 m.y. An independent survival interval cannot be determined. All of the Early- and Middletriangularis Zone should be assigned to the recovery interval, in which conodonts recovered also in a stepwise pattern and on a global scale.Pal. praetriangularis, Pal. triangularis andIcriodus alternatus, I. praealternatus, I. deformatus asymmetricus are crisis progenitor taxa, which are important for conodont recovery in the pelagic and neritic facies respectively. Some species ofPolygnathus andIcriodus are ecological generalists.

Four new species of the conodont genus Hindeodus , Hindeodus eurypyge sp. nov., Hindeodus inflatus sp. nov., Hindeodus sp. nov. A and Hindeodus sp. nov. B, are described from the Permian–Triassic transition in South China. Our study confirms the first appearance of Hindeodus parvus at the GSSP level, base of bed 27c at Meishan. However, at Shangsi the first occurrence of H. parvus is about 4.5 m above the event boundary. Analysis of conodont biostratigraphy of the Meishan D section and the Shangsi section suggest significant differences between the two sections. These include the absence of H. changxingensis Wang from the Shangsi section and the approximately 4.5 m of the Shangsi section that contains H. priscus (Kozur), H. latidentatus (Kozur) and H. eurypyge n.sp. below the first occurrence of H. parvus . These differences may be accounted for most easily by suggesting that there is a minor depositional hiatus at the Permian–Triassic boundary GSSP level as based on the first appearance of the conodont Hindeodus parvus in Meishan section D. Taxonomic re-evaluation of Hindeodus Pa elements indicates that species of the genus can be broadly separated into two groups based on the morphology of the posterior portion of the element and on growth patterns. The stable Pa element morphology of Hindeodus , first developed in the Carboniferous, was replaced by a complex of rapid evolutionary change in the latest Permian and Early Triassic, with as many as 11 valid species of the genus in the Permian–Triassic boundary interval, which are probably descendants of only two species, H. typicalis and H. n.sp. B. We suggest that the dramatic change in conodont biofacies observed at the P–T boundary in South China from Neogondolella -dominated faunas to Hindeodus -dominated faunas was caused by the introduction of a high component of silt, beginning in bed 27 at Meishan and bed 28 at Shangsi, that tipped the environmental balance in favor of Hindeodus and Isarcicella over Neogondolella ( Clarkina ) species. We contend that Hindeodus species were adaptable to higher levels of turbidity than Neogondolella ( Clarkina ) species and hence at Meishan and Shangsi it was not a matter of a drastic increase in the abundance of Hindeodus , but an exclusion of Neogondolella .

The B cells translocation gene 1 (BTG1) is a member of the BTG/TOB family of anti-proliferative genes, which have recently emerged as important regulators of cell growth and differentiation among vertebrates. Here, for the first time we cloned the full-length cDNA sequence of Hyriopsis schlegelii (Hs-BTG1), an economically important freshwater shellfish and potential indicator of environmental heavy metal pollution, for the first time. Using rapid amplification of cDNA ends (RACE) together with splicing the EST sequence from a haemocyte cDNA library, we found that Hs-BTG1 contains a 525 bp open reading frame (ORF) encoding a 174 amino-acid polypeptide, a 306 bp 5' untranslated region (5' UTR), and a 571 bp 3' UTR with a Poly(A) tail as well as a transcription termination signal (AATAAA). Homologue searching against GenBank revealed that Hs-BTG1 was closest to Crassostrea gigas BTG1, sharing 50.57% of protein identities. Hs-BTG1 also shares some typical features of the BTG/TOB family, possessing two well-conserved A and B boxes. Clustering analysis of Hs-BTG1 and other known BTGs showed that Hs-BTG1 was also closely related to BTG1 of C. gigas from the invertebrate BTG1 clade. Function prediction via homology modeling showed that both Hs-BTG1 and C. gigas BTG1 share a similar three-dimensional structure with Homo sapiens BTG1. Tissue-specific expression analysis of the Hs-BTG1 via real-time PCR showed that the transcripts were constitutively expressed, with the highest levels in the hepatopancreas and gills, and the lowest in both haemocyte and muscle tissue. Expression levels of Hs-BTG1 in hepatopancreas (2.03-fold), mantle (2.07-fold), kidney (2.2-fold) and haemocyte (2.5-fold) were enhanced by cadmium (Cd2+) stress, suggesting that Hs-BTG1 may have played a significant role in H. schlegelii adaptation to adverse environmental conditions.